DRILL-8291: Allow Case Sensitive Filters in HTTP Plugin

contrib/storage-http/README.md

@@ -306,6 +306,9 @@ on 400 series errors, `false` will return an empty result set (with implicit fie
 Default is `true`, but when set to false, Drill will trust all SSL certificates.  Useful for debugging or on internal corporate networks using self-signed certificates or 
 private certificate authorities.
 
+#### caseSensitiveFilters
+Some APIs are case sensitive with the fields which are pushed down.  If the endpoint that you are working with is in fact case sensitive, simply set this to `true`.  Defaults to `false`.
+
 ## Usage
 
 This plugin is different from other plugins in that it the table component of the `FROM` clause
@@ -577,9 +580,9 @@ ORDER BY issue_count DESC
    you may encounter errors or empty responses if you are counting on the endpoint for
    redirection.
 
-2. At this time, the plugin does not support any authentication other than basic authentication.
+~~2. At this time, the plugin does not support any authentication other than basic authentication.~~
 
-3. This plugin does not implement join filter pushdowns (only constant plushdowns are
+3. This plugin does not implement join filter pushdowns (only constant pushdowns are
    supported). Join pushdown has the potential to improve performance if you use the HTTP service
    joined to another table.
 

contrib/storage-http/src/main/java/org/apache/drill/exec/store/http/HttpApiConfig.java

@@ -104,6 +104,9 @@ public class HttpApiConfig {
   @JsonProperty
   private final boolean errorOn400;
 
+  @JsonProperty
+  private final boolean caseSensitiveFilters;
+
   // Enables the user to configure JSON options at the connection level rather than globally.
   @JsonProperty
   private final HttpJsonOptions jsonOptions;
@@ -157,6 +160,10 @@ public String inputType() {
     return this.inputType;
   }
 
+  public boolean caseSensitiveFilters() {
+    return this.caseSensitiveFilters;
+  }
+
   public int xmlDataLevel() {
     return this.xmlDataLevel;
   }
@@ -199,6 +206,7 @@ public boolean equals(Object o) {
       && errorOn400 == that.errorOn400
       && verifySSLCert == that.verifySSLCert
       && directCredentials == that.directCredentials
+      && caseSensitiveFilters == that.caseSensitiveFilters
       && Objects.equals(url, that.url)
       && Objects.equals(method, that.method)
       && Objects.equals(postBody, that.postBody)
@@ -218,7 +226,7 @@ public boolean equals(Object o) {
   public int hashCode() {
     return Objects.hash(url, requireTail, method, postBody, headers, params, dataPath,
       authType, inputType, xmlDataLevel, limitQueryParam, errorOn400, jsonOptions, verifySSLCert,
-      credentialsProvider, paginator, directCredentials, postParameterLocation);
+      credentialsProvider, paginator, directCredentials, postParameterLocation, caseSensitiveFilters);
   }
 
   @Override
@@ -232,6 +240,7 @@ public String toString() {
       .field("headers", headers)
       .field("params", params)
       .field("dataPath", dataPath)
+      .field("caseSensitiveFilters", caseSensitiveFilters)
       .field("authType", authType)
       .field("inputType", inputType)
       .field("xmlDataLevel", xmlDataLevel)
@@ -328,6 +337,7 @@ private HttpApiConfig(HttpApiConfig.HttpApiConfigBuilder builder) {
 
     this.xmlDataLevel = Math.max(1, builder.xmlDataLevel);
     this.errorOn400 = builder.errorOn400;
+    this.caseSensitiveFilters = builder.caseSensitiveFilters;
     this.credentialsProvider = CredentialProviderUtils.getCredentialsProvider(builder.userName, builder.password, builder.credentialsProvider);
     this.directCredentials = builder.credentialsProvider == null;
 
@@ -422,7 +432,7 @@ public static class HttpApiConfigBuilder {
     private String authType;
 
     private int xmlDataLevel;
-
+    private boolean caseSensitiveFilters;
     private String limitQueryParam;
 
     private boolean errorOn400;
@@ -489,6 +499,11 @@ public HttpApiConfigBuilder url(String url) {
       return this;
     }
 
+    public HttpApiConfigBuilder caseSensitiveFilters(boolean caseSensitiveFilters) {
+      this.caseSensitiveFilters = caseSensitiveFilters;
+      return this;
+    }
+
     public HttpApiConfigBuilder method(String method) {
       this.method = method;
       return this;

contrib/storage-http/src/main/java/org/apache/drill/exec/store/http/HttpPushDownListener.java

@@ -35,6 +35,7 @@
 import org.apache.drill.exec.store.http.util.SimpleHttp;
 
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -175,7 +176,13 @@ private boolean acceptType(MinorType type) {
      */
     @Override
     public Pair<GroupScan, List<RexNode>> transform(AndNode andNode) {
-      Map<String, String> filters = CaseInsensitiveMap.newHashMap();
+      Map<String, String> filters;
+      if (groupScan.getHttpConfig().caseSensitiveFilters()) {
+        filters = new HashMap<>();
+      } else {
+        filters = CaseInsensitiveMap.newHashMap();
+      }
+
       double selectivity = 1;
       for (ExprNode expr : andNode.children) {
         ColRelOpConstNode relOp = (ColRelOpConstNode) expr;

contrib/storage-http/src/main/java/org/apache/drill/exec/store/http/util/SimpleHttp.java

@@ -35,7 +35,6 @@
 import org.apache.drill.common.exceptions.EmptyErrorContext;
 import org.apache.drill.common.logical.OAuthConfig;
 import org.apache.drill.common.logical.StoragePluginConfig.AuthMode;
-import org.apache.drill.common.map.CaseInsensitiveMap;
 import org.apache.drill.common.exceptions.CustomErrorContext;
 import org.apache.drill.common.exceptions.UserException;
 import org.apache.drill.exec.ExecConstants;
@@ -712,7 +711,6 @@ public static String mapURLParameters(HttpUrl url, Map<String, String> filters)
         .message("API Query with URL Parameters must be populated.")
         .build(logger);
     }
-    CaseInsensitiveMap<String>caseInsensitiveFilterMap = (CaseInsensitiveMap<String>)filters;
 
     List<String> params = SimpleHttp.getURLParameters(url);
     String tempUrl = SimpleHttp.decodedURL(url);
@@ -726,7 +724,7 @@ public static String mapURLParameters(HttpUrl url, Map<String, String> filters)
       //     of providing helpful errors in strange cases, it is there.
 
 
-      String value = caseInsensitiveFilterMap.get(param);
+      String value = filters.get(param);
 
       // Check and see if there is a default for this parameter. If not throw an error.
       if (StringUtils.isEmpty(value)) {