From 74f35d82cfd29f8a2ecaff2982207e63eea4afc5 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Tue, 1 Dec 2020 18:07:00 +0100
Subject: [PATCH 01/21] Introduce Eclipse MicroProfile Config API to the
 project. #7000

---
 pom.xml | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/pom.xml b/pom.xml
index bdd60965137..02d457cd99f 100644
--- a/pom.xml
+++ b/pom.xml
@@ -280,6 +280,11 @@
             <version>29.0-jre</version>
             <type>jar</type>
         </dependency>
+        <dependency>
+            <groupId>org.eclipse.microprofile.config</groupId>
+            <artifactId>microprofile-config-api</artifactId>
+            <scope>provided</scope>
+        </dependency>
         <dependency>
             <groupId>jakarta.platform</groupId>
             <artifactId>jakarta.jakartaee-api</artifactId>

From 13447f9cd3e27b78834b41520449424c57f3b6f4 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Fri, 4 Dec 2020 13:30:59 +0100
Subject: [PATCH 02/21] Add MicroBean MicroProfile Config API implementation as
 a test dependency to enable unit and integration testing without deployments.
 #7000

---
 pom.xml | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/pom.xml b/pom.xml
index 02d457cd99f..652a435639f 100644
--- a/pom.xml
+++ b/pom.xml
@@ -35,6 +35,7 @@
         <junit.jupiter.version>5.7.0</junit.jupiter.version>
         <junit.vintage.version>${junit.jupiter.version}</junit.vintage.version>
         <testcontainers.version>1.13.0</testcontainers.version>
+        <microbean-mpconfig.version>0.4.1</microbean-mpconfig.version>
         <mockito.version>2.28.2</mockito.version>
         <flyway.version>5.2.4</flyway.version>
         <jhove.version>1.20.1</jhove.version>
@@ -654,7 +655,12 @@
             <version>${mockito.version}</version>
             <scope>test</scope>
         </dependency>
-        
+        <dependency>
+            <groupId>org.microbean</groupId>
+            <artifactId>microbean-microprofile-config</artifactId>
+            <version>${microbean-mpconfig.version}</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
     <build>
         <!--        <testResources>

From a74cc52331cee3a7fa58497dfa0f99b6ec33d6d3 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Fri, 4 Dec 2020 13:31:26 +0100
Subject: [PATCH 03/21] Update Testcontainers to 1.15.0.

---
 pom.xml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pom.xml b/pom.xml
index 652a435639f..4d59037d999 100644
--- a/pom.xml
+++ b/pom.xml
@@ -34,7 +34,7 @@
         <junit.version>4.13.1</junit.version>
         <junit.jupiter.version>5.7.0</junit.jupiter.version>
         <junit.vintage.version>${junit.jupiter.version}</junit.vintage.version>
-        <testcontainers.version>1.13.0</testcontainers.version>
+        <testcontainers.version>1.15.0</testcontainers.version>
         <microbean-mpconfig.version>0.4.1</microbean-mpconfig.version>
         <mockito.version>2.28.2</mockito.version>
         <flyway.version>5.2.4</flyway.version>

From a535ce84583dbbe461e2a20a5b1437fdc1506457 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Mon, 7 Dec 2020 22:14:28 +0100
Subject: [PATCH 04/21] Introducing an MPCONFIG alias config source. #7457

---
 .../settings/source/AliasConfigSource.java    | 78 +++++++++++++++++++
 .../spi/AliasConfigSourceProvider.java        | 14 ++++
 .../META-INF/aliases-config.properties        |  4 +
 ...croprofile.config.spi.ConfigSourceProvider |  1 +
 4 files changed, 97 insertions(+)
 create mode 100644 src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
 create mode 100644 src/main/java/edu/harvard/iq/dataverse/settings/spi/AliasConfigSourceProvider.java
 create mode 100644 src/main/resources/META-INF/aliases-config.properties
 create mode 100644 src/main/resources/META-INF/services/org.eclipse.microprofile.config.spi.ConfigSourceProvider

diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
new file mode 100644
index 00000000000..32896460933
--- /dev/null
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
@@ -0,0 +1,78 @@
+package edu.harvard.iq.dataverse.settings.source;
+
+import org.eclipse.microprofile.config.ConfigProvider;
+import org.eclipse.microprofile.config.spi.ConfigSource;
+
+import java.io.IOException;
+import java.net.URL;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Properties;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.logging.Logger;
+
+public final class AliasConfigSource implements ConfigSource {
+    
+    private static final Logger logger = Logger.getLogger(AliasConfigSource.class.getName());
+    
+    private final ConcurrentHashMap<String, String> aliases = new ConcurrentHashMap<>();
+    private final String ALIASES_PROP_FILE = "aliases-config.properties";
+    
+    public AliasConfigSource() {
+        try {
+            // get resource from classpath
+            ClassLoader classLoader = this.getClass().getClassLoader();
+            URL aliasesResource = classLoader.getResource(ALIASES_PROP_FILE);
+            
+            // load properties from file resource (parsing included)
+            Properties aliasProps = new Properties();
+            aliasProps.load(aliasesResource.openStream());
+    
+            // store in our aliases map
+            aliasProps.forEach((key, value) -> aliases.put(key.toString(), value.toString()));
+        } catch (IOException e) {
+            logger.info("Could not read from "+ALIASES_PROP_FILE+". Skipping MPCONFIG alias setup.");
+        }
+    }
+    
+    @Override
+    public Map<String, String> getProperties() {
+        // No, just no. We're not going to drop a list of stuff. We're only
+        // dealiasing on getValue();
+        return new HashMap<>();
+    }
+    
+    @Override
+    public Set<String> getPropertyNames() {
+        // It does not make sense to retrieve the aliased names...
+        return new HashSet<>();
+    }
+    
+    @Override
+    public int getOrdinal() {
+        // Any other config source can override us.
+        // As soon as someone is starting to use the new property name, this alias becomes pointless.
+        return Integer.MIN_VALUE;
+    }
+    
+    @Override
+    public String getValue(String key) {
+        String value = null;
+        if (this.aliases.contains(key)) {
+            String oldKey = this.aliases.get(key);
+            value = ConfigProvider.getConfig().getOptionalValue(oldKey, String.class).orElse(null);
+            
+            if (value != null) {
+                logger.warning("Detected deprecated config option '"+oldKey+"' in use. Please update your config to use '"+key+"'.");
+            }
+        }
+        return value;
+    }
+    
+    @Override
+    public String getName() {
+        return null;
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/spi/AliasConfigSourceProvider.java b/src/main/java/edu/harvard/iq/dataverse/settings/spi/AliasConfigSourceProvider.java
new file mode 100644
index 00000000000..05d88d2c892
--- /dev/null
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/spi/AliasConfigSourceProvider.java
@@ -0,0 +1,14 @@
+package edu.harvard.iq.dataverse.settings.spi;
+
+import edu.harvard.iq.dataverse.settings.source.AliasConfigSource;
+import org.eclipse.microprofile.config.spi.ConfigSource;
+import org.eclipse.microprofile.config.spi.ConfigSourceProvider;
+
+import java.util.Arrays;
+
+public class AliasConfigSourceProvider implements ConfigSourceProvider {
+    @Override
+    public Iterable<ConfigSource> getConfigSources(ClassLoader forClassLoader) {
+        return Arrays.asList(new AliasConfigSource());
+    }
+}
\ No newline at end of file
diff --git a/src/main/resources/META-INF/aliases-config.properties b/src/main/resources/META-INF/aliases-config.properties
new file mode 100644
index 00000000000..4efaf02b083
--- /dev/null
+++ b/src/main/resources/META-INF/aliases-config.properties
@@ -0,0 +1,4 @@
+# NOTE
+# This file is a placeholder for future aliases of deprecated config settings.
+# Format:
+# dataverse.new.config.option=dataverse.old.deprecated.option
\ No newline at end of file
diff --git a/src/main/resources/META-INF/services/org.eclipse.microprofile.config.spi.ConfigSourceProvider b/src/main/resources/META-INF/services/org.eclipse.microprofile.config.spi.ConfigSourceProvider
new file mode 100644
index 00000000000..796f03d7ce3
--- /dev/null
+++ b/src/main/resources/META-INF/services/org.eclipse.microprofile.config.spi.ConfigSourceProvider
@@ -0,0 +1 @@
+edu.harvard.iq.dataverse.settings.spi.AliasConfigSourceProvider

From 7a2433eb32559203be94ac872b43b7ee1cef5081 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Mon, 7 Dec 2020 23:06:44 +0100
Subject: [PATCH 05/21] Add missing name to AliasConfigSource. #7457

---
 .../harvard/iq/dataverse/settings/source/AliasConfigSource.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
index 32896460933..bc401195a9f 100644
--- a/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
@@ -73,6 +73,6 @@ public String getValue(String key) {
     
     @Override
     public String getName() {
-        return null;
+        return "Alias";
     }
 }
\ No newline at end of file

From f7407e359c5fd64d32ef7a64bcc575783667a8e9 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Mon, 7 Dec 2020 23:09:05 +0100
Subject: [PATCH 06/21] Adding a config source to retrieve Dataverse DB
 settings from MicroProfile Config API

---
 .../source/DbSettingConfigSource.java         | 85 +++++++++++++++++++
 .../spi/DbSettingConfigSourceProvider.java    | 14 +++
 ...croprofile.config.spi.ConfigSourceProvider |  1 +
 3 files changed, 100 insertions(+)
 create mode 100644 src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
 create mode 100644 src/main/java/edu/harvard/iq/dataverse/settings/spi/DbSettingConfigSourceProvider.java

diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
new file mode 100644
index 00000000000..1820d246859
--- /dev/null
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
@@ -0,0 +1,85 @@
+package edu.harvard.iq.dataverse.settings.source;
+
+import org.eclipse.microprofile.config.spi.ConfigSource;
+
+import javax.naming.InitialContext;
+import javax.naming.NamingException;
+import javax.sql.DataSource;
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.time.Duration;
+import java.time.Instant;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+public class DbSettingConfigSource implements ConfigSource {
+    
+    static final String PREFIX = "dataverse.settings.fromdb";
+    static final ConcurrentHashMap<String, String> propertiesCache = new ConcurrentHashMap<>();
+    static Instant lastUpdate;
+    
+    DataSource dataSource;
+    
+    public DbSettingConfigSource() {
+        try {
+            dataSource = (DataSource) new InitialContext().lookup("java:app/jdbc/dataverse");
+            updateProperties();
+        } catch (final NamingException e) {
+            throw new IllegalStateException(e);
+        }
+    }
+    
+    public void updateProperties() {
+        // Do brutal JDBC retrieval over the wire, to be available right from the start of app deployment.
+        // Injecting the EntityManager or the SettingsServiceBean is hard, as MPCONFIG sources are POJOs.
+        // We would need to be a Startup-Singleton, but this means no values for early retrieval...
+        try {
+            final Connection connection = dataSource.getConnection();
+            final PreparedStatement query = connection.prepareStatement("SELECT name, content FROM Setting WHERE lang IS NULL");
+            final ResultSet props = query.executeQuery();
+        
+            while (props.next()) {
+                propertiesCache.put(PREFIX+"."+props.getString(0), props.getString(1));
+            }
+            lastUpdate = Instant.now();
+        
+            props.close();
+            query.close();
+            connection.close();
+        } catch (final SQLException e) {
+            e.printStackTrace();
+        }
+    }
+    
+    @Override
+    public Map<String, String> getProperties() {
+        // if the cache is at least XX number of seconds old, update before serving data.
+        if (lastUpdate == null || Instant.now().minus(Duration.ofSeconds(60)).isBefore(lastUpdate)) {
+            updateProperties();
+        }
+        return propertiesCache;
+    }
+    
+    @Override
+    public Set<String> getPropertyNames() {
+        return getProperties().keySet();
+    }
+    
+    @Override
+    public int getOrdinal() {
+        return 0;
+    }
+    
+    @Override
+    public String getValue(String key) {
+        return getProperties().getOrDefault(key, null);
+    }
+    
+    @Override
+    public String getName() {
+        return "DataverseDB";
+    }
+}
diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/spi/DbSettingConfigSourceProvider.java b/src/main/java/edu/harvard/iq/dataverse/settings/spi/DbSettingConfigSourceProvider.java
new file mode 100644
index 00000000000..856a2c64a01
--- /dev/null
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/spi/DbSettingConfigSourceProvider.java
@@ -0,0 +1,14 @@
+package edu.harvard.iq.dataverse.settings.spi;
+
+import edu.harvard.iq.dataverse.settings.source.DbSettingConfigSource;
+import org.eclipse.microprofile.config.spi.ConfigSource;
+import org.eclipse.microprofile.config.spi.ConfigSourceProvider;
+
+import java.util.Arrays;
+
+public class DbSettingConfigSourceProvider implements ConfigSourceProvider {
+    @Override
+    public Iterable<ConfigSource> getConfigSources(ClassLoader forClassLoader) {
+        return Arrays.asList(new DbSettingConfigSource());
+    }
+}
\ No newline at end of file
diff --git a/src/main/resources/META-INF/services/org.eclipse.microprofile.config.spi.ConfigSourceProvider b/src/main/resources/META-INF/services/org.eclipse.microprofile.config.spi.ConfigSourceProvider
index 796f03d7ce3..f2e23ca1b4e 100644
--- a/src/main/resources/META-INF/services/org.eclipse.microprofile.config.spi.ConfigSourceProvider
+++ b/src/main/resources/META-INF/services/org.eclipse.microprofile.config.spi.ConfigSourceProvider
@@ -1 +1,2 @@
 edu.harvard.iq.dataverse.settings.spi.AliasConfigSourceProvider
+edu.harvard.iq.dataverse.settings.spi.DbSettingConfigSourceProvider

From 620e9abb8d52741786217ec84fd0a8a9cf9bcd51 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Mon, 7 Dec 2020 23:35:08 +0100
Subject: [PATCH 07/21] Refactor AliasConfigSource to be more testable and
 rename aliases file to microprofile-aliases.properties. #7457

---
 .../settings/source/AliasConfigSource.java    | 33 +++++++++++++------
 ...erties => microprofile-aliases.properties} |  0
 2 files changed, 23 insertions(+), 10 deletions(-)
 rename src/main/resources/META-INF/{aliases-config.properties => microprofile-aliases.properties} (100%)

diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
index bc401195a9f..5fae130a3a1 100644
--- a/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
@@ -18,25 +18,38 @@ public final class AliasConfigSource implements ConfigSource {
     private static final Logger logger = Logger.getLogger(AliasConfigSource.class.getName());
     
     private final ConcurrentHashMap<String, String> aliases = new ConcurrentHashMap<>();
-    private final String ALIASES_PROP_FILE = "aliases-config.properties";
+    private final String ALIASES_PROP_FILE = "META-INF/microprofile-aliases.properties";
     
     public AliasConfigSource() {
         try {
-            // get resource from classpath
-            ClassLoader classLoader = this.getClass().getClassLoader();
-            URL aliasesResource = classLoader.getResource(ALIASES_PROP_FILE);
-            
-            // load properties from file resource (parsing included)
-            Properties aliasProps = new Properties();
-            aliasProps.load(aliasesResource.openStream());
-    
+            // read properties from class path file
+            Properties aliasProps = readAliases(ALIASES_PROP_FILE);
             // store in our aliases map
-            aliasProps.forEach((key, value) -> aliases.put(key.toString(), value.toString()));
+            importAliases(aliasProps);
         } catch (IOException e) {
             logger.info("Could not read from "+ALIASES_PROP_FILE+". Skipping MPCONFIG alias setup.");
         }
     }
     
+    Properties readAliases(String filePath) throws IOException {
+        // get resource from classpath
+        ClassLoader classLoader = this.getClass().getClassLoader();
+        URL aliasesResource = classLoader.getResource(filePath);
+    
+        // load properties from file resource (parsing included)
+        Properties aliasProps = new Properties();
+        try {
+            aliasProps.load(aliasesResource.openStream());
+        } catch (NullPointerException e) {
+            throw new IOException(e.getMessage());
+        }
+        return aliasProps;
+    }
+    
+    void importAliases(Properties aliasProps) {
+        aliasProps.forEach((key, value) -> aliases.put(key.toString(), value.toString()));
+    }
+    
     @Override
     public Map<String, String> getProperties() {
         // No, just no. We're not going to drop a list of stuff. We're only
diff --git a/src/main/resources/META-INF/aliases-config.properties b/src/main/resources/META-INF/microprofile-aliases.properties
similarity index 100%
rename from src/main/resources/META-INF/aliases-config.properties
rename to src/main/resources/META-INF/microprofile-aliases.properties

From ebf83e22ab8681ece09d45b9a957abb4a7aeaf12 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Mon, 7 Dec 2020 23:55:41 +0100
Subject: [PATCH 08/21] Fix error in AliasConfigSource, not looking at keys but
 values of the map. #7457

---
 .../harvard/iq/dataverse/settings/source/AliasConfigSource.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
index 5fae130a3a1..cca33fb581a 100644
--- a/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
@@ -73,7 +73,7 @@ public int getOrdinal() {
     @Override
     public String getValue(String key) {
         String value = null;
-        if (this.aliases.contains(key)) {
+        if (this.aliases.containsKey(key)) {
             String oldKey = this.aliases.get(key);
             value = ConfigProvider.getConfig().getOptionalValue(oldKey, String.class).orElse(null);
             

From e1cb339b8650629ca93381d8e50479af6ecaa488 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Mon, 7 Dec 2020 23:56:05 +0100
Subject: [PATCH 09/21] Add tests for AliasConfigSource. #7457

---
 .../source/AliasConfigSourceTest.java         | 41 +++++++++++++++++++
 .../test-microprofile-aliases.properties      |  1 +
 2 files changed, 42 insertions(+)
 create mode 100644 src/test/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSourceTest.java
 create mode 100644 src/test/resources/test-microprofile-aliases.properties

diff --git a/src/test/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSourceTest.java b/src/test/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSourceTest.java
new file mode 100644
index 00000000000..36c4d99f743
--- /dev/null
+++ b/src/test/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSourceTest.java
@@ -0,0 +1,41 @@
+package edu.harvard.iq.dataverse.settings.source;
+
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+import java.util.Properties;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class AliasConfigSourceTest {
+    
+    AliasConfigSource source = new AliasConfigSource();
+    
+    @Test
+    void getValue() {
+        // given
+        System.setProperty("dataverse.hello.foobar", "test");
+        Properties aliases = new Properties();
+        aliases.setProperty("dataverse.goodbye.foobar", "dataverse.hello.foobar");
+        
+        // when
+        source.importAliases(aliases);
+        
+        // then
+        assertEquals("test", source.getValue("dataverse.goodbye.foobar"));
+    }
+    
+    @Test
+    void readImportTestAliasesFromFile() throws IOException {
+        // given
+        System.setProperty("dataverse.old.example", "test");
+        String filePath = "test-microprofile-aliases.properties";
+        
+        // when
+        Properties aliases = source.readAliases(filePath);
+        source.importAliases(aliases);
+        
+        // then
+        assertEquals("test", source.getValue("dataverse.new.example"));
+    }
+}
\ No newline at end of file
diff --git a/src/test/resources/test-microprofile-aliases.properties b/src/test/resources/test-microprofile-aliases.properties
new file mode 100644
index 00000000000..4ee67025920
--- /dev/null
+++ b/src/test/resources/test-microprofile-aliases.properties
@@ -0,0 +1 @@
+dataverse.new.example=dataverse.old.example
\ No newline at end of file

From fdb043d82e77e4c5a8c65d1ab448f4ba83a1cc3f Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Tue, 8 Dec 2020 01:23:35 +0100
Subject: [PATCH 10/21] Add integration testing for DbSettingConfigSource to
 ensure data retrieval works. Fixing a typo, too. #7457

---
 pom.xml                                       |  9 ++++
 .../source/DbSettingConfigSource.java         | 10 ++++-
 .../source/DbSettingConfigSourceIT.java       | 42 +++++++++++++++++++
 .../sql/dbsetting-config-source-testdata.sql  | 11 +++++
 4 files changed, 70 insertions(+), 2 deletions(-)
 create mode 100644 src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceIT.java
 create mode 100644 src/test/resources/sql/dbsetting-config-source-testdata.sql

diff --git a/pom.xml b/pom.xml
index db96ae29f4c..6da5755517b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -643,6 +643,11 @@
             <artifactId>junit-jupiter</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>postgresql</artifactId>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-core</artifactId>
@@ -855,6 +860,7 @@
             <id>tc</id>
             <properties>
                 <skipUnitTests>true</skipUnitTests>
+                <postgresql.server.version>9.6</postgresql.server.version>
             </properties>
             <build>
                 <plugins>
@@ -864,6 +870,9 @@
                         <version>2.22.2</version>
                         <configuration>
                             <groups>testcontainers</groups>
+                            <systemPropertyVariables>
+                                <postgresql.server.version>${postgresql.server.version}</postgresql.server.version>
+                            </systemPropertyVariables>
                         </configuration>
                         <executions>
                             <execution>
diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
index 1820d246859..5038e5c7714 100644
--- a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
@@ -32,6 +32,12 @@ public DbSettingConfigSource() {
         }
     }
     
+    // Test usage (no JNDI context)
+    public DbSettingConfigSource(DataSource ds) {
+        dataSource = ds;
+        updateProperties();
+    }
+    
     public void updateProperties() {
         // Do brutal JDBC retrieval over the wire, to be available right from the start of app deployment.
         // Injecting the EntityManager or the SettingsServiceBean is hard, as MPCONFIG sources are POJOs.
@@ -42,7 +48,7 @@ public void updateProperties() {
             final ResultSet props = query.executeQuery();
         
             while (props.next()) {
-                propertiesCache.put(PREFIX+"."+props.getString(0), props.getString(1));
+                propertiesCache.put(PREFIX+"."+props.getString(1), props.getString(2));
             }
             lastUpdate = Instant.now();
         
@@ -70,7 +76,7 @@ public Set<String> getPropertyNames() {
     
     @Override
     public int getOrdinal() {
-        return 0;
+        return 50;
     }
     
     @Override
diff --git a/src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceIT.java b/src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceIT.java
new file mode 100644
index 00000000000..274e3cc65e0
--- /dev/null
+++ b/src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceIT.java
@@ -0,0 +1,42 @@
+package edu.harvard.iq.dataverse.settings.source;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Tag;
+import org.junit.jupiter.api.Test;
+import org.postgresql.ds.PGSimpleDataSource;
+import org.testcontainers.containers.JdbcDatabaseContainer;
+import org.testcontainers.containers.PostgreSQLContainer;
+import org.testcontainers.junit.jupiter.Container;
+import org.testcontainers.junit.jupiter.Testcontainers;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@Tag("testcontainers")
+@Testcontainers
+class DbSettingConfigSourceIT {
+
+    @Container
+    static JdbcDatabaseContainer dbContainer = new PostgreSQLContainer("postgres:"+System.getProperty("postgresql.server.version", "9.6"))
+                                                        .withInitScript("sql/dbsetting-config-source-testdata.sql")
+                                                        .withDatabaseName("dataverse");
+    
+    static DbSettingConfigSource dbSource;
+    
+    @BeforeAll
+    static void setUp() {
+        // create the datasource
+        PGSimpleDataSource ds = new PGSimpleDataSource();
+        ds.setURL(dbContainer.getJdbcUrl());
+        ds.setUser(dbContainer.getUsername());
+        ds.setPassword(dbContainer.getPassword());
+        
+        // create the config source
+        dbSource = new DbSettingConfigSource(ds);
+    }
+    
+    @Test
+    void testDataRetrieval() {
+        assertEquals("foobar@example.org", dbSource.getValue("dataverse.settings.fromdb.SystemEmail"));
+    }
+
+}
\ No newline at end of file
diff --git a/src/test/resources/sql/dbsetting-config-source-testdata.sql b/src/test/resources/sql/dbsetting-config-source-testdata.sql
new file mode 100644
index 00000000000..c55162d8707
--- /dev/null
+++ b/src/test/resources/sql/dbsetting-config-source-testdata.sql
@@ -0,0 +1,11 @@
+CREATE TABLE Setting (
+    id            char(5) CONSTRAINT firstkey PRIMARY KEY,
+    name          varchar(40) NOT NULL,
+    content       varchar(40) NOT NULL,
+    lang          varchar(40) DEFAULT NULL
+);
+
+INSERT INTO Setting (id, name, content)
+    VALUES
+        (1, 'SystemEmail', 'foobar@example.org')
+    ON CONFLICT DO NOTHING;
\ No newline at end of file

From b1ea8463e7bd2a499c59d58cee8c6130148cf4a1 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Tue, 8 Dec 2020 01:40:42 +0100
Subject: [PATCH 11/21] Change pom.xml to include the MicroProfile Config API
 SPI definitions. #7457

---
 pom.xml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/pom.xml b/pom.xml
index 6da5755517b..120c2d0ceff 100644
--- a/pom.xml
+++ b/pom.xml
@@ -702,6 +702,7 @@
                     <include>**/firstNames/*.*</include>
                     <include>**/*.xsl</include>
                     <include>**/*.properties</include>
+                    <include>**/services/*</include>
                 </includes>
             </resource>
         </resources>

From 429ea21f911313b22bbd5c13f14b1a4023aebb61 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Tue, 8 Dec 2020 01:55:40 +0100
Subject: [PATCH 12/21] Add some docs about introducing MPCONFIG to the dev
 guide.

---
 .../source/developers/configuration.rst              | 12 ++++++++++++
 doc/sphinx-guides/source/developers/index.rst        |  1 +
 doc/sphinx-guides/source/developers/intro.rst        |  2 ++
 3 files changed, 15 insertions(+)
 create mode 100644 doc/sphinx-guides/source/developers/configuration.rst

diff --git a/doc/sphinx-guides/source/developers/configuration.rst b/doc/sphinx-guides/source/developers/configuration.rst
new file mode 100644
index 00000000000..58920189d48
--- /dev/null
+++ b/doc/sphinx-guides/source/developers/configuration.rst
@@ -0,0 +1,12 @@
+Consuming Configuration
+=======================
+
+By using `MicroProfile Config <https://github.com/eclipse/microprofile-config>`_, we start to move away from
+direct ``System.getProperty()`` calls, replacing it with either injected or programmatic config retrieval.
+
+The API of MPCONFIG allows for great flexibility, type-safety, defaults etc. For system administrators
+and developers it get's much easier to provide their configuration.
+
+This technology is introduced on a step-by-step basis. There will not be a big shot, crashing upgrades for everyone.
+Instead, we will provide backward compatibility by deprecating renamed or moved config options, while still
+supporting the old way of setting them.
\ No newline at end of file
diff --git a/doc/sphinx-guides/source/developers/index.rst b/doc/sphinx-guides/source/developers/index.rst
index 9c524571a39..184d8aff85a 100755
--- a/doc/sphinx-guides/source/developers/index.rst
+++ b/doc/sphinx-guides/source/developers/index.rst
@@ -22,6 +22,7 @@ Developer Guide
    dependencies
    debugging
    coding-style
+   configuration
    deployment
    containers
    making-releases
diff --git a/doc/sphinx-guides/source/developers/intro.rst b/doc/sphinx-guides/source/developers/intro.rst
index 2ce9c52bd37..e7ed6a12a37 100755
--- a/doc/sphinx-guides/source/developers/intro.rst
+++ b/doc/sphinx-guides/source/developers/intro.rst
@@ -28,6 +28,8 @@ Dataverse is a `Jakarta EE <https://en.wikipedia.org/wiki/Jakarta_EE>`_ applicat
 
 We make use of a variety of Jakarta EE technologies such as JPA, JAX-RS, JMS, and JSF. The front end is built using PrimeFaces and Bootstrap.
 
+In addition, we start to adopt parts of Eclipse MicroProfile, namely `MicroProfile Config <https://github.com/eclipse/microprofile-config>`_.
+
 Roadmap
 -------
 

From 5f73b45a6822083265e4226f8589000c03076a1c Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Tue, 8 Dec 2020 19:42:06 +0100
Subject: [PATCH 13/21] Extend dev docs about MPCONFIG. #7457

---
 .../source/developers/configuration.rst       | 77 +++++++++++++++++--
 1 file changed, 72 insertions(+), 5 deletions(-)

diff --git a/doc/sphinx-guides/source/developers/configuration.rst b/doc/sphinx-guides/source/developers/configuration.rst
index 58920189d48..dcc7e8d54ea 100644
--- a/doc/sphinx-guides/source/developers/configuration.rst
+++ b/doc/sphinx-guides/source/developers/configuration.rst
@@ -1,12 +1,79 @@
 Consuming Configuration
 =======================
 
-By using `MicroProfile Config <https://github.com/eclipse/microprofile-config>`_, we start to move away from
-direct ``System.getProperty()`` calls, replacing it with either injected or programmatic config retrieval.
+Dataverse uses different types of configuration:
 
-The API of MPCONFIG allows for great flexibility, type-safety, defaults etc. For system administrators
-and developers it get's much easier to provide their configuration.
+1. JVM system properties
+2. Simple database value settings
+3. Complex database stored data structures
+
+1 and 2 are usually simple text strings, boolean switches or digits. All of those can be found in :doc:`/installation/config`.
+
+Anything for 3 is configured via the API using either TSV or JSON structures. Examples are metadata blocks,
+authentication providers, harvesters and others.
+
+Simple Configuration Options
+----------------------------
+
+Developers have accessed the simple properties via
+
+1. ``System.getProperty(...)`` for JVM system property settings
+2. ``SettingsServiceBean.get(...)`` for database settings and
+3. ``SystemConfig.xxx()`` for specially treated settings, maybe mixed from 1 and 2 and other sources.
+
+As of Dataverse 5.3, we start to streamline our efforts into using a more consistent approach, also bringing joy and
+happiness to all the system administrators out there. This will be done by adopting the use of
+`MicroProfile Config <https://github.com/eclipse/microprofile-config>`_ over time.
+
+So far we streamlined configuration of these Dataverse parts:
+
+- ✅ Database Connection
+
+Complex Configuration Options
+-----------------------------
+
+We should enable variable substitution in JSON configuration. Example: using substitution to retrieve values from
+MicroProfile Config and insert into the authentication provider would allow much easier provisioning of secrets
+into the providers.
+
+Why should I care about MicroProfile Config API?
+------------------------------------------------
+
+Developers benefit from:
+
+- A streamlined API to retrieve configuration, backward-compatible renaming strategies and easier testbed configurations.
+- Config API is also pushing for validation of configuration, as it's typesafe and converters for non-standard types
+  can be added within our codebase.
+- Defaults in code or bundled in ``META-INF/microprofile-config.properties`` allow for optional values without much hassle.
+
+System administrators benefit from:
+
+- Lots of database settings have been introduced in the past, but should be more easily configurable and not rely on a
+  database connection.
+- Running Dataverse in containers gets much easier when configuration can be provisioned in a
+  streamlined fashion, mitigating the need for scripting glue and distinguishing between setting types.
+- Classic installations have a profit, too: we can enable using a single config file, e.g. living in
+  ``/etc/dataverse/config.properties``.
+- Features for monitoring resources and others are easier to use with this streamlined configuration, as we can
+  avoid people having to deal with ``asadmin`` commands and change a setting comfortably instead.
+
+Adopting MicroProfile Config API
+---------------------------------
 
 This technology is introduced on a step-by-step basis. There will not be a big shot, crashing upgrades for everyone.
 Instead, we will provide backward compatibility by deprecating renamed or moved config options, while still
-supporting the old way of setting them.
\ No newline at end of file
+supporting the old way of setting them.
+
+- Introducing a new setting or moving and old one should result in a key ``dataverse.<scope/task/module/...>.<setting>``.
+  That way we enable sys admins to recognize the meaning of an option and avoid name conflicts.
+  Starting with ``dataverse`` makes it perfectly clear that this is a setting meant for this application, which is
+  important when using environment variables, system properties or other MPCONFIG sources.
+- Replace ``System.getProperty()`` calls with either injected configs or retrieve programmatically if more complex
+  handling is necessary.
+- When moving a database setting (``:ExampleSetting``), configure an alias
+  ``dataverse.my.example.setting=dataverse.settings.fromdb.ExampleSetting`` in
+  ``src/main/resources/META-INF/microprofile-aliases.properties``. This will enable backward compatibility.
+- When moving an old key to a new (especially when doing so with a former JVM system property setting), you should
+  add an alias to ``src/main/resources/META-INF/microprofile-aliases.properties`` to enable backward compatibility.
+  The format is always like ``dataverse.<scope/....>.newname...=old.property.name``.
+

From 2ffa4c120852b42752ebe47e6978355584123ac5 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Tue, 8 Dec 2020 20:59:09 +0100
Subject: [PATCH 14/21] Fix DbSettingConfigSource not to throw an exception if
 the DataSource JNDI could not be found or injected. Will result empty
 properties for this source. #7457

---
 .../settings/source/DbSettingConfigSource.java      | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
index 5038e5c7714..08af0f88142 100644
--- a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
@@ -14,12 +14,14 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.logging.Logger;
 
 public class DbSettingConfigSource implements ConfigSource {
     
-    static final String PREFIX = "dataverse.settings.fromdb";
-    static final ConcurrentHashMap<String, String> propertiesCache = new ConcurrentHashMap<>();
-    static Instant lastUpdate;
+    private static final Logger logger = Logger.getLogger(DbSettingConfigSource.class.getName());
+    private static final String PREFIX = "dataverse.settings.fromdb";
+    private static final ConcurrentHashMap<String, String> propertiesCache = new ConcurrentHashMap<>();
+    private static Instant lastUpdate;
     
     DataSource dataSource;
     
@@ -28,7 +30,7 @@ public DbSettingConfigSource() {
             dataSource = (DataSource) new InitialContext().lookup("java:app/jdbc/dataverse");
             updateProperties();
         } catch (final NamingException e) {
-            throw new IllegalStateException(e);
+            logger.warning("Could not setup MPCONFIG dataverse setting config source as no DB connection could be found.");
         }
     }
     
@@ -39,6 +41,9 @@ public DbSettingConfigSource(DataSource ds) {
     }
     
     public void updateProperties() {
+        // When the DataSource is unavailable (no db connection / ...), do not update to avoid NPEs
+        if (dataSource == null)
+            return;
         // Do brutal JDBC retrieval over the wire, to be available right from the start of app deployment.
         // Injecting the EntityManager or the SettingsServiceBean is hard, as MPCONFIG sources are POJOs.
         // We would need to be a Startup-Singleton, but this means no values for early retrieval...

From a44b0a413438c606098c06aada910aa3813b25ed Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Tue, 8 Dec 2020 23:18:10 +0100
Subject: [PATCH 15/21] Refactor DbSettingConfigSource to rely on the
 SettingsServiceBean, injected by a singleton on startup.

---
 .../source/developers/configuration.rst       |  1 +
 .../source/DbSettingConfigHelper.java         | 20 ++++++
 .../source/DbSettingConfigSource.java         | 67 ++++++-------------
 .../source/DbSettingConfigSourceIT.java       | 42 ------------
 .../source/DbSettingConfigSourceTest.java     | 48 +++++++++++++
 5 files changed, 88 insertions(+), 90 deletions(-)
 create mode 100644 src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigHelper.java
 delete mode 100644 src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceIT.java
 create mode 100644 src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceTest.java

diff --git a/doc/sphinx-guides/source/developers/configuration.rst b/doc/sphinx-guides/source/developers/configuration.rst
index dcc7e8d54ea..b4d1d21bfd5 100644
--- a/doc/sphinx-guides/source/developers/configuration.rst
+++ b/doc/sphinx-guides/source/developers/configuration.rst
@@ -20,6 +20,7 @@ Developers have accessed the simple properties via
 1. ``System.getProperty(...)`` for JVM system property settings
 2. ``SettingsServiceBean.get(...)`` for database settings and
 3. ``SystemConfig.xxx()`` for specially treated settings, maybe mixed from 1 and 2 and other sources.
+4. ``SettingsWrapper``, reading from 2 and 3 for use in frontend pages based on JSF
 
 As of Dataverse 5.3, we start to streamline our efforts into using a more consistent approach, also bringing joy and
 happiness to all the system administrators out there. This will be done by adopting the use of
diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigHelper.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigHelper.java
new file mode 100644
index 00000000000..156ea1809ca
--- /dev/null
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigHelper.java
@@ -0,0 +1,20 @@
+package edu.harvard.iq.dataverse.settings.source;
+
+import edu.harvard.iq.dataverse.settings.SettingsServiceBean;
+
+import javax.annotation.PostConstruct;
+import javax.ejb.EJB;
+import javax.ejb.Singleton;
+import javax.ejb.Startup;
+
+@Singleton
+@Startup
+public class DbSettingConfigHelper {
+    @EJB
+    SettingsServiceBean settingsSvc;
+    
+    @PostConstruct
+    public void injectService() {
+        DbSettingConfigSource.injectSettingsService(settingsSvc);
+    }
+}
diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
index 08af0f88142..7471ad5a00f 100644
--- a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
@@ -1,68 +1,39 @@
 package edu.harvard.iq.dataverse.settings.source;
 
+import edu.harvard.iq.dataverse.settings.Setting;
+import edu.harvard.iq.dataverse.settings.SettingsServiceBean;
 import org.eclipse.microprofile.config.spi.ConfigSource;
 
-import javax.naming.InitialContext;
-import javax.naming.NamingException;
-import javax.sql.DataSource;
-import java.sql.Connection;
-import java.sql.PreparedStatement;
-import java.sql.ResultSet;
-import java.sql.SQLException;
 import java.time.Duration;
 import java.time.Instant;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
-import java.util.logging.Logger;
 
 public class DbSettingConfigSource implements ConfigSource {
     
-    private static final Logger logger = Logger.getLogger(DbSettingConfigSource.class.getName());
-    private static final String PREFIX = "dataverse.settings.fromdb";
-    private static final ConcurrentHashMap<String, String> propertiesCache = new ConcurrentHashMap<>();
+    private static final ConcurrentHashMap<String, String> properties = new ConcurrentHashMap<>();
     private static Instant lastUpdate;
+    private static SettingsServiceBean settingsSvc;
+    static final String PREFIX = "dataverse.settings.fromdb";
     
-    DataSource dataSource;
-    
-    public DbSettingConfigSource() {
-        try {
-            dataSource = (DataSource) new InitialContext().lookup("java:app/jdbc/dataverse");
-            updateProperties();
-        } catch (final NamingException e) {
-            logger.warning("Could not setup MPCONFIG dataverse setting config source as no DB connection could be found.");
-        }
+    /**
+     * Let the SettingsServiceBean be injected by DbSettingConfigHelper with PostConstruct
+     * @param injected
+     */
+    public static void injectSettingsService(SettingsServiceBean injected) {
+       settingsSvc = injected;
+       updateProperties();
     }
     
-    // Test usage (no JNDI context)
-    public DbSettingConfigSource(DataSource ds) {
-        dataSource = ds;
-        updateProperties();
-    }
-    
-    public void updateProperties() {
-        // When the DataSource is unavailable (no db connection / ...), do not update to avoid NPEs
-        if (dataSource == null)
+    public static void updateProperties() {
+        // skip if the service has not been injected yet
+        if (settingsSvc == null)
             return;
-        // Do brutal JDBC retrieval over the wire, to be available right from the start of app deployment.
-        // Injecting the EntityManager or the SettingsServiceBean is hard, as MPCONFIG sources are POJOs.
-        // We would need to be a Startup-Singleton, but this means no values for early retrieval...
-        try {
-            final Connection connection = dataSource.getConnection();
-            final PreparedStatement query = connection.prepareStatement("SELECT name, content FROM Setting WHERE lang IS NULL");
-            final ResultSet props = query.executeQuery();
-        
-            while (props.next()) {
-                propertiesCache.put(PREFIX+"."+props.getString(1), props.getString(2));
-            }
-            lastUpdate = Instant.now();
         
-            props.close();
-            query.close();
-            connection.close();
-        } catch (final SQLException e) {
-            e.printStackTrace();
-        }
+        Set<Setting> dbSettings = settingsSvc.listAll();
+        dbSettings.forEach(s -> properties.put(PREFIX+"."+s.getName()+ (s.getLang() == null ? "" : "."+s.getLang()), s.getContent()));
+        lastUpdate = Instant.now();
     }
     
     @Override
@@ -71,7 +42,7 @@ public Map<String, String> getProperties() {
         if (lastUpdate == null || Instant.now().minus(Duration.ofSeconds(60)).isBefore(lastUpdate)) {
             updateProperties();
         }
-        return propertiesCache;
+        return properties;
     }
     
     @Override
diff --git a/src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceIT.java b/src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceIT.java
deleted file mode 100644
index 274e3cc65e0..00000000000
--- a/src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceIT.java
+++ /dev/null
@@ -1,42 +0,0 @@
-package edu.harvard.iq.dataverse.settings.source;
-
-import org.junit.jupiter.api.BeforeAll;
-import org.junit.jupiter.api.Tag;
-import org.junit.jupiter.api.Test;
-import org.postgresql.ds.PGSimpleDataSource;
-import org.testcontainers.containers.JdbcDatabaseContainer;
-import org.testcontainers.containers.PostgreSQLContainer;
-import org.testcontainers.junit.jupiter.Container;
-import org.testcontainers.junit.jupiter.Testcontainers;
-
-import static org.junit.jupiter.api.Assertions.*;
-
-@Tag("testcontainers")
-@Testcontainers
-class DbSettingConfigSourceIT {
-
-    @Container
-    static JdbcDatabaseContainer dbContainer = new PostgreSQLContainer("postgres:"+System.getProperty("postgresql.server.version", "9.6"))
-                                                        .withInitScript("sql/dbsetting-config-source-testdata.sql")
-                                                        .withDatabaseName("dataverse");
-    
-    static DbSettingConfigSource dbSource;
-    
-    @BeforeAll
-    static void setUp() {
-        // create the datasource
-        PGSimpleDataSource ds = new PGSimpleDataSource();
-        ds.setURL(dbContainer.getJdbcUrl());
-        ds.setUser(dbContainer.getUsername());
-        ds.setPassword(dbContainer.getPassword());
-        
-        // create the config source
-        dbSource = new DbSettingConfigSource(ds);
-    }
-    
-    @Test
-    void testDataRetrieval() {
-        assertEquals("foobar@example.org", dbSource.getValue("dataverse.settings.fromdb.SystemEmail"));
-    }
-
-}
\ No newline at end of file
diff --git a/src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceTest.java b/src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceTest.java
new file mode 100644
index 00000000000..c886ef0ba69
--- /dev/null
+++ b/src/test/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSourceTest.java
@@ -0,0 +1,48 @@
+package edu.harvard.iq.dataverse.settings.source;
+
+import edu.harvard.iq.dataverse.settings.Setting;
+import edu.harvard.iq.dataverse.settings.SettingsServiceBean;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.MethodOrderer.OrderAnnotation;
+import org.junit.jupiter.api.Order;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestMethodOrder;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.Mockito;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Set;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@ExtendWith(MockitoExtension.class)
+@TestMethodOrder(OrderAnnotation.class)
+class DbSettingConfigSourceTest {
+
+    DbSettingConfigSource dbSource = new DbSettingConfigSource();
+    @Mock
+    SettingsServiceBean settingsSvc;
+    
+    @Test
+    @Order(1)
+    void testEmptyIfNoSettingsService() {
+        assertEquals(null, dbSource.getValue("foobar"));
+        assertDoesNotThrow(DbSettingConfigSource::updateProperties);
+    }
+    
+    @Test
+    @Order(2)
+    void testDataRetrieval() {
+        Set<Setting> settings = new HashSet<>(Arrays.asList(new Setting("FooBar", "hello"), new Setting("FooBarI18N", "de", "hallo")));
+        Mockito.when(settingsSvc.listAll()).thenReturn(settings);
+    
+        DbSettingConfigSource.injectSettingsService(settingsSvc);
+        
+        assertEquals("hello", dbSource.getValue("dataverse.settings.fromdb.FooBar"));
+        assertEquals("hallo", dbSource.getValue("dataverse.settings.fromdb.FooBarI18N.de"));
+    }
+
+}
\ No newline at end of file

From ecc277c999b861a2953b4c456626b5788e8021bf Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Tue, 8 Dec 2020 23:34:04 +0100
Subject: [PATCH 16/21] Log warning message for DbSettingConfigSource if the
 settings service has not been injected yet, but values are requested already.

---
 .../iq/dataverse/settings/source/DbSettingConfigSource.java | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
index 7471ad5a00f..2993ec5254c 100644
--- a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
@@ -9,9 +9,11 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.logging.Logger;
 
 public class DbSettingConfigSource implements ConfigSource {
     
+    private static final Logger logger = Logger.getLogger(DbSettingConfigSource.class.getCanonicalName());
     private static final ConcurrentHashMap<String, String> properties = new ConcurrentHashMap<>();
     private static Instant lastUpdate;
     private static SettingsServiceBean settingsSvc;
@@ -57,6 +59,10 @@ public int getOrdinal() {
     
     @Override
     public String getValue(String key) {
+        // log usages for which this has been designed, but not yet ready to serve...
+        if (settingsSvc == null && key.startsWith(PREFIX)) {
+            logger.severe("MPCONFIG DbSettingConfigSource not ready yet, but requested for '"+key+"'.");
+        }
         return getProperties().getOrDefault(key, null);
     }
     

From e6f38ee3abd6a4bf43664fce03cb51356100c6f5 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Wed, 9 Dec 2020 00:08:17 +0100
Subject: [PATCH 17/21] More dev documentation of MPCONFIG usage and sources.
 #7457

---
 .../source/developers/configuration.rst       | 31 ++++++++++++++-----
 .../settings/source/AliasConfigSource.java    |  7 +++++
 .../source/DbSettingConfigSource.java         |  9 ++++++
 3 files changed, 40 insertions(+), 7 deletions(-)

diff --git a/doc/sphinx-guides/source/developers/configuration.rst b/doc/sphinx-guides/source/developers/configuration.rst
index b4d1d21bfd5..b9bb3dc3fe7 100644
--- a/doc/sphinx-guides/source/developers/configuration.rst
+++ b/doc/sphinx-guides/source/developers/configuration.rst
@@ -70,11 +70,28 @@ supporting the old way of setting them.
   Starting with ``dataverse`` makes it perfectly clear that this is a setting meant for this application, which is
   important when using environment variables, system properties or other MPCONFIG sources.
 - Replace ``System.getProperty()`` calls with either injected configs or retrieve programmatically if more complex
-  handling is necessary.
-- When moving a database setting (``:ExampleSetting``), configure an alias
-  ``dataverse.my.example.setting=dataverse.settings.fromdb.ExampleSetting`` in
-  ``src/main/resources/META-INF/microprofile-aliases.properties``. This will enable backward compatibility.
-- When moving an old key to a new (especially when doing so with a former JVM system property setting), you should
-  add an alias to ``src/main/resources/META-INF/microprofile-aliases.properties`` to enable backward compatibility.
-  The format is always like ``dataverse.<scope/....>.newname...=old.property.name``.
+  handling is necessary. If you rename the property, you should provide an alias. See below.
+- Database settings need to be refactored in multiple steps. First you need to change the code retrieving it to use
+  MicroProfile Config API instead (just like above). Then you should provide an alias to retain backward compatibility.
+  See below.
 
+Moving or Replacing a JVM Setting
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+When moving an old key to a new (especially when doing so with a former JVM system property setting), you should
+add an alias to ``src/main/resources/META-INF/microprofile-aliases.properties`` to enable backward compatibility.
+The format is always like ``dataverse.<scope/....>.newname...=old.property.name``.
+
+Details can be found in ``edu.harvard.iq.dataverse.settings.source.AliasConfigSource``
+
+Aliasing Database Setting
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+When moving a database setting (``:ExampleSetting``), configure an alias
+ ``dataverse.my.example.setting=dataverse.settings.fromdb.ExampleSetting`` in
+``src/main/resources/META-INF/microprofile-aliases.properties``. This will enable backward compatibility.
+
+A database setting with an i18n attribute using *lang* will have available language codes appended to the name.
+Example: ``dataverse.settings.fromdb.ExampleI18nSetting.en``, ``dataverse.settings.fromdb.ExampleI18nSetting.de``
+
+More details in ``edu.harvard.iq.dataverse.settings.source.DbSettingConfigSource``
\ No newline at end of file
diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
index cca33fb581a..fbdbd982085 100644
--- a/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/AliasConfigSource.java
@@ -13,6 +13,13 @@
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.logging.Logger;
 
+/**
+ * Enable using an old name for a new config name.
+ * Usages will be logged and this source will ALWAYS stand back if the new name is used anywhere.
+ *
+ * By using a DbSettingConfigSource value (dataverse.settings.fromdb.XXX) as old name, we can
+ * alias a new name to an old db setting, enabling backward compatibility.
+ */
 public final class AliasConfigSource implements ConfigSource {
     
     private static final Logger logger = Logger.getLogger(AliasConfigSource.class.getName());
diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
index 2993ec5254c..597fdb314d2 100644
--- a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigSource.java
@@ -11,6 +11,12 @@
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.logging.Logger;
 
+/**
+ * A caching wrapper around SettingServiceBean to provide database settings to MicroProfile Config API.
+ * Please be aware that this class relies on dependency injection during the application startup.
+ * Values will not be available before and a severe message will be logged to allow monitoring (potential race conditions)
+ * The settings will be cached for at least one minute, avoiding unnecessary database calls.
+ */
 public class DbSettingConfigSource implements ConfigSource {
     
     private static final Logger logger = Logger.getLogger(DbSettingConfigSource.class.getCanonicalName());
@@ -28,6 +34,9 @@ public static void injectSettingsService(SettingsServiceBean injected) {
        updateProperties();
     }
     
+    /**
+     * Retrieve settings from the database via service and update cache.
+     */
     public static void updateProperties() {
         // skip if the service has not been injected yet
         if (settingsSvc == null)

From ffe775ef82a36fcc7c83375583214914c690b415 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Wed, 9 Dec 2020 00:13:43 +0100
Subject: [PATCH 18/21] Add release notes for #7457

---
 doc/release-notes/7457-introduce-mpconfig.md | 10 ++++++++++
 1 file changed, 10 insertions(+)
 create mode 100644 doc/release-notes/7457-introduce-mpconfig.md

diff --git a/doc/release-notes/7457-introduce-mpconfig.md b/doc/release-notes/7457-introduce-mpconfig.md
new file mode 100644
index 00000000000..2f90590fca5
--- /dev/null
+++ b/doc/release-notes/7457-introduce-mpconfig.md
@@ -0,0 +1,10 @@
+## Introducing MicroProfile Config API
+
+With this Dataverse release, we start to make use of the MicroProfile Config API. (As you might have noticed
+for the database connection settings.)
+
+This will benefit both devs and sysadmins, but the codebase will have to be refactored to make use of it.
+As this will take time, we will always provide a backward compatible way of using it.
+
+For more details, please see the development guide about "Consuming Configuration", which also
+explains the benefits in more detail.
\ No newline at end of file

From 00b95335e0fd312bc4649c116a06ca6470391e8e Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Wed, 9 Dec 2020 00:18:33 +0100
Subject: [PATCH 19/21] Add javadoc about what is DbSettingConfigHelper. #7457

---
 .../dataverse/settings/source/DbSettingConfigHelper.java   | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigHelper.java b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigHelper.java
index 156ea1809ca..7b9783dee06 100644
--- a/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigHelper.java
+++ b/src/main/java/edu/harvard/iq/dataverse/settings/source/DbSettingConfigHelper.java
@@ -7,6 +7,13 @@
 import javax.ejb.Singleton;
 import javax.ejb.Startup;
 
+/**
+ * This is a small helper bean for the MPCONFIG DbSettingConfigSource.
+ * As it is a singleton and built at application start (=deployment), it will inject the (stateless)
+ * settings service into the MPCONFIG POJO once it's ready.
+ *
+ * MPCONFIG requires it's sources to be POJOs. No direct dependency injection possible.
+ */
 @Singleton
 @Startup
 public class DbSettingConfigHelper {

From f4a88a12d0e995994e3e7fd589baadf861040cc5 Mon Sep 17 00:00:00 2001
From: Oliver Bertuch <o.bertuch@fz-juelich.de>
Date: Wed, 9 Dec 2020 18:48:25 +0100
Subject: [PATCH 20/21] Make Sphinx happy by removing a redundant space in dev
 docs about configuration.

---
 doc/sphinx-guides/source/developers/configuration.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/sphinx-guides/source/developers/configuration.rst b/doc/sphinx-guides/source/developers/configuration.rst
index b9bb3dc3fe7..c07a555ad1b 100644
--- a/doc/sphinx-guides/source/developers/configuration.rst
+++ b/doc/sphinx-guides/source/developers/configuration.rst
@@ -88,7 +88,7 @@ Aliasing Database Setting
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 
 When moving a database setting (``:ExampleSetting``), configure an alias
- ``dataverse.my.example.setting=dataverse.settings.fromdb.ExampleSetting`` in
+``dataverse.my.example.setting=dataverse.settings.fromdb.ExampleSetting`` in
 ``src/main/resources/META-INF/microprofile-aliases.properties``. This will enable backward compatibility.
 
 A database setting with an i18n attribute using *lang* will have available language codes appended to the name.

From f1350509d37f9fcb4c7993f45cc61dc28151806f Mon Sep 17 00:00:00 2001
From: Philip Durbin <philip_durbin@harvard.edu>
Date: Wed, 9 Dec 2020 13:29:45 -0500
Subject: [PATCH 21/21] add toc #7457

---
 doc/sphinx-guides/source/developers/configuration.rst | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/doc/sphinx-guides/source/developers/configuration.rst b/doc/sphinx-guides/source/developers/configuration.rst
index c07a555ad1b..d058a1e1705 100644
--- a/doc/sphinx-guides/source/developers/configuration.rst
+++ b/doc/sphinx-guides/source/developers/configuration.rst
@@ -1,6 +1,9 @@
 Consuming Configuration
 =======================
 
+.. contents:: |toctitle|
+	:local:
+
 Dataverse uses different types of configuration:
 
 1. JVM system properties
@@ -94,4 +97,4 @@ When moving a database setting (``:ExampleSetting``), configure an alias
 A database setting with an i18n attribute using *lang* will have available language codes appended to the name.
 Example: ``dataverse.settings.fromdb.ExampleI18nSetting.en``, ``dataverse.settings.fromdb.ExampleI18nSetting.de``
 
-More details in ``edu.harvard.iq.dataverse.settings.source.DbSettingConfigSource``
\ No newline at end of file
+More details in ``edu.harvard.iq.dataverse.settings.source.DbSettingConfigSource``