For #206. Adding prune method to Volumes

src/main/java/com/amihaiemil/docker/RtVolumes.java

@@ -25,9 +25,11 @@
  */
 package com.amihaiemil.docker;
 
-import org.apache.http.client.HttpClient;
-
+import java.io.IOException;
 import java.net.URI;
+import org.apache.http.HttpStatus;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpPost;
 
 /**
  * Runtime {@link Volumes}.
@@ -63,6 +65,21 @@ abstract class RtVolumes implements Volumes {
         this.docker = dkr;
     }
 
+    @Override
+    public void prune() throws IOException, UnexpectedResponseException {
+        final HttpPost prune = new HttpPost(
+            this.baseUri.toString().concat("/prune")
+        );
+        try {
+            this.client.execute(
+                prune,
+                new MatchStatus(prune.getURI(), HttpStatus.SC_OK)
+            );
+        } finally {
+            prune.releaseConnection();
+        }
+    }
+
     @Override
     public Docker docker() {
         return this.docker;

src/main/java/com/amihaiemil/docker/Volumes.java

@@ -25,16 +25,25 @@
  */
 package com.amihaiemil.docker;
 
+import java.io.IOException;
+
 /**
  * Volumes API.
  * @author Mihai Andronache (amihaiemil@gmail.com)
  * @author Boris Kuzmic (boris.kuzmic@gmail.com)
  * @version $Id$
  * @since 0.0.1
- * @todo #180:30min Continue implementing prune volumes operation.
  */
 public interface Volumes extends Iterable<Volume> {
 
+    /**
+     * Deletes unused volumes.
+     * @throws IOException If an I/O error occurs.
+     * @throws UnexpectedResponseException If the API responds with an
+     *  unexpected status.
+     */
+    void prune() throws IOException, UnexpectedResponseException;
+
     /**
      * Return the Docker engine where these Images came from.
      * @return Docker.

src/test/java/com/amihaiemil/docker/RtVolumesTestCase.java

@@ -0,0 +1,89 @@
+package com.amihaiemil.docker;
+
+import com.amihaiemil.docker.mock.AssertRequest;
+import com.amihaiemil.docker.mock.Condition;
+import com.amihaiemil.docker.mock.Response;
+import java.net.URI;
+import javax.json.Json;
+import org.apache.http.HttpStatus;
+import org.hamcrest.MatcherAssert;
+import org.hamcrest.core.IsEqual;
+import org.junit.Test;
+import org.mockito.Mockito;
+
+
+/**
+ * Unit tests for {@link RtVolumes}.
+ * @author Boris Kuzmic (boris.kuzmic@gmail.com)
+ * @since 0.0.7
+ * @checkstyle MethodName (500 lines)
+ */
+public final class RtVolumesTestCase {
+
+    /**
+     * Mock docker.
+     */
+    private static final Docker DOCKER = Mockito.mock(Docker.class);
+
+    /**
+     * RtVolumes.prune() sends correct request and exist successfully on
+     * response code 200.
+     * @throws Exception If an error occurs.
+     */
+    @Test
+    public void prunesOk() throws Exception {
+        new ListedVolumes(
+            new AssertRequest(
+                new Response(HttpStatus.SC_OK),
+                new Condition(
+                    "prune() must send a POST request",
+                    req -> "POST".equals(req.getRequestLine().getMethod())
+                ),
+                new Condition(
+                    "prune() resource URL must be '/volumes/prune'",
+                    req -> req.getRequestLine()
+                        .getUri().endsWith("/volumes/prune")
+                )
+            ),
+            URI.create("http://localhost/volumes"),
+            DOCKER
+        ).prune();
+    }
+
+    /**
+     * RtVolumes.prune() must throw UnexpectedResponseException if service
+     * responds with 500.
+     * @throws Exception The UnexpectedResponseException.
+     */
+    @Test(expected = UnexpectedResponseException.class)
+    public void pruneThrowsErrorOnResponse500() throws Exception {
+        new ListedVolumes(
+            new AssertRequest(
+                new Response(HttpStatus.SC_INTERNAL_SERVER_ERROR)
+            ),
+            URI.create("http://localhost/volumes"),
+            DOCKER
+        ).prune();
+    }
+
+    /**
+     * RtVolumes can return its Docker parent.
+     */
+    @Test
+    public void returnsDocker() {
+        MatcherAssert.assertThat(
+            new ListedVolumes(
+                new AssertRequest(
+                    new Response(
+                        HttpStatus.SC_OK,
+                        Json.createArrayBuilder().build().toString()
+                    )
+                ),
+                URI.create("http://localhost"),
+                DOCKER
+            ).docker(),
+            new IsEqual<>(DOCKER)
+        );
+    }
+
+}