SONAR-6652 ws system/db_migration_status status of database migration

7 files changed, 497 insertions, 137 deletions

diff --git a/server/sonar-server/src/main/java/org/sonar/server/platform/platformlevel/PlatformLevel4.java b/server/sonar-server/src/main/java/org/sonar/server/platform/platformlevel/PlatformLevel4.java
index 26c3a75f8a9..92cdbaaa37d 100644
--- a/server/sonar-server/src/main/java/org/sonar/server/platform/platformlevel/PlatformLevel4.java
+++ b/server/sonar-server/src/main/java/org/sonar/server/platform/platformlevel/PlatformLevel4.java
@@ -185,6 +185,7 @@ import org.sonar.server.platform.monitoring.JvmPropertiesMonitor;
 import org.sonar.server.platform.monitoring.PluginsMonitor;
 import org.sonar.server.platform.monitoring.SonarQubeMonitor;
 import org.sonar.server.platform.monitoring.SystemMonitor;
+import org.sonar.server.platform.ws.DbMigrationStatusAction;
 import org.sonar.server.platform.ws.InfoAction;
 import org.sonar.server.platform.ws.L10nWs;
 import org.sonar.server.platform.ws.MigrateDbAction;
@@ -694,7 +695,6 @@ public class PlatformLevel4 extends PlatformLevel {
       RestartAction.class,
       InfoAction.class,
       UpgradesAction.class,
-      MigrateDbAction.class,
       StatusAction.class,
       SystemWs.class,
       SystemMonitor.class,
@@ -703,6 +703,8 @@ public class PlatformLevel4 extends PlatformLevel {
       PluginsMonitor.class,
       JvmPropertiesMonitor.class,
       DatabaseMonitor.class,
+      MigrateDbAction.class,
+      DbMigrationStatusAction.class,
 
       // Plugins WS
       PluginWSCommons.class,
diff --git a/server/sonar-server/src/main/java/org/sonar/server/platform/platformlevel/PlatformLevelSafeMode.java b/server/sonar-server/src/main/java/org/sonar/server/platform/platformlevel/PlatformLevelSafeMode.java
index c1445a403b6..190436d17f5 100644
--- a/server/sonar-server/src/main/java/org/sonar/server/platform/platformlevel/PlatformLevelSafeMode.java
+++ b/server/sonar-server/src/main/java/org/sonar/server/platform/platformlevel/PlatformLevelSafeMode.java
@@ -19,6 +19,7 @@
  */
 package org.sonar.server.platform.platformlevel;
 
+import org.sonar.server.platform.ws.DbMigrationStatusAction;
 import org.sonar.server.platform.ws.MigrateDbAction;
 import org.sonar.server.platform.ws.StatusAction;
 import org.sonar.server.platform.ws.SystemWs;
@@ -36,6 +37,7 @@ public class PlatformLevelSafeMode extends PlatformLevel {
       // Server WS
       StatusAction.class,
       MigrateDbAction.class,
+      DbMigrationStatusAction.class,
       SystemWs.class,
 
       // Listing WS
diff --git a/server/sonar-server/src/main/java/org/sonar/server/platform/ws/DbMigrationJsonWriter.java b/server/sonar-server/src/main/java/org/sonar/server/platform/ws/DbMigrationJsonWriter.java
new file mode 100644
index 00000000000..567d06800f5
--- /dev/null
+++ b/server/sonar-server/src/main/java/org/sonar/server/platform/ws/DbMigrationJsonWriter.java
@@ -0,0 +1,132 @@
+/*
+ * SonarQube, open source software quality management tool.
+ * Copyright (C) 2008-2014 SonarSource
+ * mailto:contact AT sonarsource DOT com
+ *
+ * SonarQube is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * SonarQube is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+package org.sonar.server.platform.ws;
+
+import org.sonar.api.utils.text.JsonWriter;
+import org.sonar.db.version.DatabaseMigration;
+
+import static org.sonar.db.version.DatabaseMigration.Status.NONE;
+import static org.sonar.db.version.DatabaseMigration.Status.RUNNING;
+
+public class DbMigrationJsonWriter {
+  static final String FIELD_STATE = "state";
+  static final String FIELD_MESSAGE = "message";
+  static final String FIELD_STARTED_AT = "startedAt";
+
+  static final String STATUS_NO_MIGRATION = "NO_MIGRATION";
+  static final String STATUS_NOT_SUPPORTED = "NOT_SUPPORTED";
+  static final String STATUS_MIGRATION_RUNNING = "MIGRATION_RUNNING";
+  static final String STATUS_MIGRATION_FAILED = "MIGRATION_FAILED";
+  static final String STATUS_MIGRATION_SUCCEEDED = "MIGRATION_SUCCEEDED";
+
+  static final String UNSUPPORTED_DATABASE_MIGRATION_STATUS = "Unsupported DatabaseMigration status";
+  static final String MESSAGE_NO_MIGRATION_ON_EMBEDDED_DATABASE = "Upgrade is not supported on embedded database.";
+  static final String MESSAGE_MIGRATION_NEEDED = "Database migration is required. DB migration can be started using WS /api/system/migrate_db.";
+  static final String MESSAGE_STATUS_NONE = "Database is up-to-date, no migration needed.";
+  static final String MESSAGE_STATUS_RUNNING = "Database migration is running.";
+  static final String MESSAGE_STATUS_SUCCEEDED = "Migration succeeded.";
+  static final String MESSAGE_STATUS_FAILED = "Migration failed: %s.<br/> Please check logs.";
+
+  private DbMigrationJsonWriter() {
+    // static methods only
+  }
+
+  static void write(JsonWriter json, DatabaseMigration databaseMigration) {
+    json.beginObject()
+      .prop(FIELD_STATE, statusToJson(databaseMigration.status()))
+      .prop(FIELD_MESSAGE, buildMessage(databaseMigration))
+      .propDateTime(FIELD_STARTED_AT, databaseMigration.startedAt())
+      .endObject();
+  }
+
+  static void writeNotSupportedResponse(JsonWriter json) {
+    json.beginObject()
+      .prop(FIELD_STATE, STATUS_NOT_SUPPORTED)
+      .prop(FIELD_MESSAGE, MESSAGE_NO_MIGRATION_ON_EMBEDDED_DATABASE)
+      .endObject();
+  }
+
+  static void writeJustStartedResponse(JsonWriter json, DatabaseMigration databaseMigration) {
+    json.beginObject()
+      .prop(FIELD_STATE, statusToJson(RUNNING))
+      .prop(FIELD_MESSAGE, MESSAGE_STATUS_RUNNING)
+      .propDateTime(FIELD_STARTED_AT, databaseMigration.startedAt())
+      .endObject();
+  }
+
+  static void writeMigrationNeededResponse(JsonWriter json) {
+    json.beginObject()
+      .prop(FIELD_STATE, statusToJson(NONE))
+      .prop(FIELD_MESSAGE, MESSAGE_MIGRATION_NEEDED)
+      .endObject();
+  }
+
+  private static String statusToJson(DatabaseMigration.Status status) {
+    switch (status) {
+      case NONE:
+        return STATUS_NO_MIGRATION;
+      case RUNNING:
+        return STATUS_MIGRATION_RUNNING;
+      case FAILED:
+        return STATUS_MIGRATION_FAILED;
+      case SUCCEEDED:
+        return STATUS_MIGRATION_SUCCEEDED;
+      default:
+        throw new IllegalArgumentException(
+          "Unsupported DatabaseMigration.Status " + status + " can not be converted to JSON value");
+    }
+  }
+
+  private static String buildMessage(DatabaseMigration databaseMigration) {
+    switch (databaseMigration.status()) {
+      case NONE:
+        return MESSAGE_STATUS_NONE;
+      case RUNNING:
+        return MESSAGE_STATUS_RUNNING;
+      case SUCCEEDED:
+        return MESSAGE_STATUS_SUCCEEDED;
+      case FAILED:
+        return String.format(MESSAGE_STATUS_FAILED, failureMessage(databaseMigration));
+      default:
+        return UNSUPPORTED_DATABASE_MIGRATION_STATUS;
+    }
+  }
+
+  private static String failureMessage(DatabaseMigration databaseMigration) {
+    Throwable failureError = databaseMigration.failureError();
+    if (failureError == null) {
+      return "No failure error";
+    }
+    return failureError.getMessage();
+  }
+
+  static String statusDescription() {
+    return
+    "State values are:" +
+      "<ul>" +
+      "<li>NO_MIGRATION: DB is up to date with current version of SonarQube.</li>" +
+      "<li>NOT_SUPPORTED: Migration is not supported on embedded databases.</li>" +
+      "<li>MIGRATION_RUNNING: DB migration is under go.</li>" +
+      "<li>MIGRATION_SUCCEEDED: DB migration has run and has been successful.</li>" +
+      "<li>MIGRATION_FAILED: DB migration has run and failed. SonarQube must be restarted in order to retry a " +
+      "DB migration (optionally after DB has been restored from backup).</li>";
+  }
+}
diff --git a/server/sonar-server/src/main/java/org/sonar/server/platform/ws/DbMigrationStatusAction.java b/server/sonar-server/src/main/java/org/sonar/server/platform/ws/DbMigrationStatusAction.java
new file mode 100644
index 00000000000..0710c1ed472
--- /dev/null
+++ b/server/sonar-server/src/main/java/org/sonar/server/platform/ws/DbMigrationStatusAction.java
@@ -0,0 +1,92 @@
+/*
+ * SonarQube, open source software quality management tool.
+ * Copyright (C) 2008-2014 SonarSource
+ * mailto:contact AT sonarsource DOT com
+ *
+ * SonarQube is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * SonarQube is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+package org.sonar.server.platform.ws;
+
+import com.google.common.io.Resources;
+import org.sonar.api.server.ws.Request;
+import org.sonar.api.server.ws.Response;
+import org.sonar.api.server.ws.WebService;
+import org.sonar.api.utils.text.JsonWriter;
+import org.sonar.db.Database;
+import org.sonar.db.version.DatabaseMigration;
+import org.sonar.db.version.DatabaseVersion;
+
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.UNSUPPORTED_DATABASE_MIGRATION_STATUS;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.statusDescription;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.write;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.writeMigrationNeededResponse;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.writeNotSupportedResponse;
+
+/**
+ * Implementation of the {@code db_migration_status} action for the System WebService.
+ */
+public class DbMigrationStatusAction implements SystemWsAction {
+
+  private final DatabaseVersion databaseVersion;
+  private final DatabaseMigration databaseMigration;
+  private final Database database;
+
+  public DbMigrationStatusAction(DatabaseVersion databaseVersion, Database database, DatabaseMigration databaseMigration) {
+    this.databaseVersion = databaseVersion;
+    this.database = database;
+    this.databaseMigration = databaseMigration;
+  }
+
+  @Override
+  public void define(WebService.NewController controller) {
+    controller.createAction("db_migration_status")
+      .setDescription("Display the database migration status of SonarQube." +
+        "<br/>" +
+        statusDescription())
+      .setSince("5.2")
+      .setHandler(this)
+      .setResponseExample(Resources.getResource(this.getClass(), "example-migrate_db.json"));
+  }
+
+  @Override
+  public void handle(Request request, Response response) throws Exception {
+    Integer currentVersion = databaseVersion.getVersion();
+
+    JsonWriter json = response.newJsonWriter();
+    try {
+      if (currentVersion >= DatabaseVersion.LAST_VERSION) {
+        write(json, databaseMigration);
+      } else if (!database.getDialect().supportsMigration()) {
+        writeNotSupportedResponse(json);
+      } else {
+        switch (databaseMigration.status()) {
+          case RUNNING:
+          case FAILED:
+          case SUCCEEDED:
+            write(json, databaseMigration);
+            break;
+          case NONE:
+            writeMigrationNeededResponse(json);
+            break;
+          default:
+            throw new IllegalArgumentException(UNSUPPORTED_DATABASE_MIGRATION_STATUS);
+        }
+      }
+    } finally {
+      json.close();
+    }
+  }
+}
diff --git a/server/sonar-server/src/main/java/org/sonar/server/platform/ws/MigrateDbAction.java b/server/sonar-server/src/main/java/org/sonar/server/platform/ws/MigrateDbAction.java
index 206d12a972a..80e82906290 100644
--- a/server/sonar-server/src/main/java/org/sonar/server/platform/ws/MigrateDbAction.java
+++ b/server/sonar-server/src/main/java/org/sonar/server/platform/ws/MigrateDbAction.java
@@ -28,29 +28,17 @@ import org.sonar.db.Database;
 import org.sonar.db.version.DatabaseMigration;
 import org.sonar.db.version.DatabaseVersion;
 
-import static org.sonar.db.version.DatabaseMigration.Status.RUNNING;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.UNSUPPORTED_DATABASE_MIGRATION_STATUS;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.statusDescription;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.write;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.writeJustStartedResponse;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.writeNotSupportedResponse;
 
 /**
  * Implementation of the {@code migrate_db} action for the System WebService.
  */
 public class MigrateDbAction implements SystemWsAction {
 
-  private static final String UNSUPPORTED_DATABASE_MIGRATION_STATUS = "Unsupported DatabaseMigration status";
-  private static final String MESSAGE_STATUS_NONE = "Database is up-to-date, no migration needed.";
-  private static final String MESSAGE_STATUS_RUNNING = "Database migration is running.";
-  private static final String MESSAGE_STATUS_SUCCEEDED = "Migration succeeded.";
-  private static final String MESSAGE_STATUS_FAILED = "Migration failed: %s.<br/> Please check logs.";
-
-  private static final String STATUS_NO_MIGRATION = "NO_MIGRATION";
-  private static final String STATUS_NOT_SUPPORTED = "NOT_SUPPORTED";
-  private static final String STATUS_MIGRATION_RUNNING = "MIGRATION_RUNNING";
-  private static final String STATUS_MIGRATION_FAILED = "MIGRATION_FAILED";
-  private static final String STATUS_MIGRATION_SUCCEEDED = "MIGRATION_SUCCEEDED";
-
-  private static final String PROPERTY_STATE = "state";
-  private static final String PROPERTY_MESSAGE = "message";
-  private static final String PROPERTY_STARTED_AT = "startedAt";
-
   private final DatabaseVersion databaseVersion;
   private final DatabaseMigration databaseMigration;
   private final Database database;
@@ -69,15 +57,7 @@ public class MigrateDbAction implements SystemWsAction {
         "Sending a POST request to this URL starts the DB migration. " +
         "It is strongly advised to <strong>make a database backup</strong> before invoking this WS." +
         "<br/>" +
-        "State values are:" +
-        "<ul>" +
-        "<li>NO_MIGRATION: DB is up to date with current version of SonarQube.</li>" +
-        "<li>NOT_SUPPORTED: Migration is not supported on embedded databases.</li>" +
-        "<li>MIGRATION_RUNNING: DB migration is under go.</li>" +
-        "<li>MIGRATION_SUCCEEDED: DB migration has run and has been successful.</li>" +
-        "<li>MIGRATION_FAILED: DB migration has run and failed. SonarQube must be restarted in order to retry a " +
-        "DB migration (optionally after DB has been restored from backup).</li>" +
-        "</ul>")
+        statusDescription())
       .setSince("5.2")
       .setPost(true)
       .setHandler(this)
@@ -91,93 +71,29 @@ public class MigrateDbAction implements SystemWsAction {
       throw new IllegalStateException("Version can not be retrieved from Database. Database is either blank or corrupted");
     }
 
-    if (currentVersion >= DatabaseVersion.LAST_VERSION) {
-      writeResponse(response, databaseMigration);
-    } else if (!database.getDialect().supportsMigration()) {
-      writeNotSupportedResponse(response);
-    } else {
-      switch (databaseMigration.status()) {
-        case RUNNING:
-        case FAILED:
-        case SUCCEEDED:
-          writeResponse(response, databaseMigration);
-          break;
-        case NONE:
-          databaseMigration.startIt();
-          writeNoneResponse(response, databaseMigration);
-          break;
-        default:
-          throw new IllegalArgumentException(UNSUPPORTED_DATABASE_MIGRATION_STATUS);
+    JsonWriter json = response.newJsonWriter();
+    try {
+      if (currentVersion >= DatabaseVersion.LAST_VERSION) {
+        write(json, databaseMigration);
+      } else if (!database.getDialect().supportsMigration()) {
+        writeNotSupportedResponse(json);
+      } else {
+        switch (databaseMigration.status()) {
+          case RUNNING:
+          case FAILED:
+          case SUCCEEDED:
+            write(json, databaseMigration);
+            break;
+          case NONE:
+            databaseMigration.startIt();
+            writeJustStartedResponse(json, databaseMigration);
+            break;
+          default:
+            throw new IllegalArgumentException(UNSUPPORTED_DATABASE_MIGRATION_STATUS);
+        }
       }
+    } finally {
+      json.close();
     }
   }
-
-  private static void writeNotSupportedResponse(Response response) {
-    JsonWriter jsonWriter = response.newJsonWriter();
-    jsonWriter.beginObject()
-      .prop(PROPERTY_STATE, STATUS_NOT_SUPPORTED)
-      .prop(PROPERTY_MESSAGE, "Upgrade is not supported on embedded database.")
-      .endObject();
-    jsonWriter.close();
-  }
-
-  private void writeNoneResponse(Response response, DatabaseMigration databaseMigration) {
-    JsonWriter jsonWriter = response.newJsonWriter();
-    jsonWriter.beginObject()
-      .prop(PROPERTY_STATE, statusToJson(RUNNING))
-      .prop(PROPERTY_MESSAGE, MESSAGE_STATUS_RUNNING)
-      .propDateTime(PROPERTY_STARTED_AT, databaseMigration.startedAt())
-      .endObject();
-    jsonWriter.close();
-  }
-
-  private void writeResponse(Response response, DatabaseMigration databaseMigration) {
-    JsonWriter jsonWriter = response.newJsonWriter();
-    jsonWriter.beginObject()
-      .prop(PROPERTY_STATE, statusToJson(databaseMigration.status()))
-      .prop(PROPERTY_MESSAGE, buildMessage(databaseMigration))
-      .propDateTime(PROPERTY_STARTED_AT, databaseMigration.startedAt())
-      .endObject();
-    jsonWriter.close();
-  }
-
-  private String statusToJson(DatabaseMigration.Status status) {
-    switch (status) {
-      case NONE:
-        return STATUS_NO_MIGRATION;
-      case RUNNING:
-        return STATUS_MIGRATION_RUNNING;
-      case FAILED:
-        return STATUS_MIGRATION_FAILED;
-      case SUCCEEDED:
-        return STATUS_MIGRATION_SUCCEEDED;
-      default:
-        throw new IllegalArgumentException(
-          "Unsupported DatabaseMigration.Status " + status + " can not be converted to JSON value");
-    }
-  }
-
-  private static String buildMessage(DatabaseMigration databaseMigration) {
-    switch (databaseMigration.status()) {
-      case NONE:
-        return MESSAGE_STATUS_NONE;
-      case RUNNING:
-        return MESSAGE_STATUS_RUNNING;
-      case SUCCEEDED:
-        return MESSAGE_STATUS_SUCCEEDED;
-      case FAILED:
-        return String.format(MESSAGE_STATUS_FAILED, failureMessage(databaseMigration));
-      default:
-        return UNSUPPORTED_DATABASE_MIGRATION_STATUS;
-    }
-  }
-
-  private static String failureMessage(DatabaseMigration databaseMigration) {
-    Throwable failureError = databaseMigration.failureError();
-    if (failureError == null) {
-      return "No failure error";
-    }
-    return failureError.getMessage();
-  }
-
 }
diff --git a/server/sonar-server/src/test/java/org/sonar/server/platform/ws/DbMigrationStatusActionTest.java b/server/sonar-server/src/test/java/org/sonar/server/platform/ws/DbMigrationStatusActionTest.java
new file mode 100644
index 00000000000..81153c39368
--- /dev/null
+++ b/server/sonar-server/src/test/java/org/sonar/server/platform/ws/DbMigrationStatusActionTest.java
@@ -0,0 +1,214 @@
+/*
+ * SonarQube, open source software quality management tool.
+ * Copyright (C) 2008-2014 SonarSource
+ * mailto:contact AT sonarsource DOT com
+ *
+ * SonarQube is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * SonarQube is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+package org.sonar.server.platform.ws;
+
+import com.google.common.collect.ImmutableList;
+import java.util.Arrays;
+import java.util.Date;
+import javax.annotation.Nullable;
+import org.junit.Before;
+import org.junit.Test;
+import org.sonar.api.server.ws.Request;
+import org.sonar.api.utils.DateUtils;
+import org.sonar.db.Database;
+import org.sonar.db.dialect.Dialect;
+import org.sonar.db.version.DatabaseMigration;
+import org.sonar.db.version.DatabaseMigration.Status;
+import org.sonar.db.version.DatabaseVersion;
+import org.sonar.server.ws.WsTester;
+
+import static com.google.common.base.Predicates.in;
+import static com.google.common.base.Predicates.not;
+import static com.google.common.collect.Iterables.filter;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+import static org.sonar.db.version.DatabaseMigration.Status.FAILED;
+import static org.sonar.db.version.DatabaseMigration.Status.NONE;
+import static org.sonar.db.version.DatabaseMigration.Status.RUNNING;
+import static org.sonar.db.version.DatabaseMigration.Status.SUCCEEDED;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.MESSAGE_MIGRATION_NEEDED;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.MESSAGE_NO_MIGRATION_ON_EMBEDDED_DATABASE;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.MESSAGE_STATUS_NONE;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.MESSAGE_STATUS_RUNNING;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.MESSAGE_STATUS_SUCCEEDED;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.STATUS_MIGRATION_FAILED;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.STATUS_MIGRATION_RUNNING;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.STATUS_MIGRATION_SUCCEEDED;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.STATUS_NOT_SUPPORTED;
+import static org.sonar.server.platform.ws.DbMigrationJsonWriter.STATUS_NO_MIGRATION;
+import static org.sonar.test.JsonAssert.assertJson;
+
+public class DbMigrationStatusActionTest {
+
+  private static final Date SOME_DATE = new Date();
+  private static final String SOME_THROWABLE_MSG = "blablabla pop !";
+  private static final String DEFAULT_ERROR_MSG = "No failure error";
+  private static final int CURRENT_VERSION = DatabaseVersion.LAST_VERSION;
+  private static final int OLD_VERSION = CURRENT_VERSION - 1;
+  private static final int NEWER_VERSION = CURRENT_VERSION + 1;
+
+  DatabaseVersion databaseVersion = mock(DatabaseVersion.class);
+  Database database = mock(Database.class);
+  Dialect dialect = mock(Dialect.class);
+  DatabaseMigration databaseMigration = mock(DatabaseMigration.class);
+  DbMigrationStatusAction underTest = new DbMigrationStatusAction(databaseVersion, database, databaseMigration);
+
+  Request request = mock(Request.class);
+  WsTester.TestResponse response = new WsTester.TestResponse();
+
+  @Before
+  public void wireMocksTogether() {
+    when(database.getDialect()).thenReturn(dialect);
+  }
+
+  @Test
+  public void verify_example() throws Exception {
+    when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
+    when(dialect.supportsMigration()).thenReturn(true);
+    when(databaseMigration.status()).thenReturn(RUNNING);
+    when(databaseMigration.startedAt()).thenReturn(DateUtils.parseDateTime("2015-02-23T18:54:23+0100"));
+    underTest.handle(request, response);
+
+    assertJson(response.outputAsString()).isSimilarTo(getClass().getResource("example-migrate_db.json"));
+  }
+
+  @Test
+  public void msg_is_operational_and_state_from_databasemigration_when_databaseversion_is_equal_to_currentversion() throws Exception {
+    when(databaseVersion.getVersion()).thenReturn(CURRENT_VERSION);
+    when(databaseMigration.status()).thenReturn(NONE);
+
+    underTest.handle(request, response);
+
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_NO_MIGRATION, MESSAGE_STATUS_NONE));
+  }
+
+  // this test will raise a IllegalArgumentException when an unsupported value is added to the Status enum
+  @Test
+  public void defensive_test_all_values_of_Status_must_be_supported() throws Exception {
+    for (Status status : filter(Arrays.asList(Status.values()), not(in(ImmutableList.of(NONE, RUNNING, FAILED, SUCCEEDED))))) {
+      when(databaseVersion.getVersion()).thenReturn(CURRENT_VERSION);
+      when(databaseMigration.status()).thenReturn(status);
+
+      underTest.handle(request, response);
+    }
+  }
+
+  @Test
+  public void state_from_databasemigration_when_databaseversion_greater_than_currentversion() throws Exception {
+    when(databaseVersion.getVersion()).thenReturn(NEWER_VERSION);
+    when(databaseMigration.status()).thenReturn(NONE);
+
+    underTest.handle(request, response);
+
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_NO_MIGRATION, MESSAGE_STATUS_NONE));
+  }
+
+  @Test
+  public void state_is_NONE_with_specific_msg_when_version_is_less_than_current_version_and_dialect_does_not_support_migration() throws Exception {
+    when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
+    when(dialect.supportsMigration()).thenReturn(false);
+
+    underTest.handle(request, response);
+
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_NOT_SUPPORTED, MESSAGE_NO_MIGRATION_ON_EMBEDDED_DATABASE));
+  }
+
+  @Test
+  public void state_from_databasemigration_when_dbmigration_status_is_RUNNING() throws Exception {
+    when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
+    when(dialect.supportsMigration()).thenReturn(true);
+    when(databaseMigration.status()).thenReturn(RUNNING);
+    when(databaseMigration.startedAt()).thenReturn(SOME_DATE);
+
+    underTest.handle(request, response);
+
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_MIGRATION_RUNNING, MESSAGE_STATUS_RUNNING, SOME_DATE));
+  }
+
+  @Test
+  public void state_from_databasemigration_and_msg_includes_error_when_dbmigration_status_is_FAILED() throws Exception {
+    when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
+    when(dialect.supportsMigration()).thenReturn(true);
+    when(databaseMigration.status()).thenReturn(FAILED);
+    when(databaseMigration.startedAt()).thenReturn(SOME_DATE);
+    when(databaseMigration.failureError()).thenReturn(new UnsupportedOperationException(SOME_THROWABLE_MSG));
+
+    underTest.handle(request, response);
+
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_MIGRATION_FAILED, failedMsg(SOME_THROWABLE_MSG), SOME_DATE));
+  }
+
+  @Test
+  public void state_from_databasemigration_and_msg_has_default_msg_when_dbmigration_status_is_FAILED() throws Exception {
+    when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
+    when(dialect.supportsMigration()).thenReturn(true);
+    when(databaseMigration.status()).thenReturn(FAILED);
+    when(databaseMigration.startedAt()).thenReturn(SOME_DATE);
+    when(databaseMigration.failureError()).thenReturn(null); // no failure throwable caught
+
+    underTest.handle(request, response);
+
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_MIGRATION_FAILED, failedMsg(DEFAULT_ERROR_MSG), SOME_DATE));
+  }
+
+  @Test
+  public void state_from_databasemigration_and_msg_has_default_msg_when_dbmigration_status_is_SUCCEEDED() throws Exception {
+    when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
+    when(dialect.supportsMigration()).thenReturn(true);
+    when(databaseMigration.status()).thenReturn(SUCCEEDED);
+    when(databaseMigration.startedAt()).thenReturn(SOME_DATE);
+
+    underTest.handle(request, response);
+
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_MIGRATION_SUCCEEDED, MESSAGE_STATUS_SUCCEEDED, SOME_DATE));
+  }
+
+  @Test
+  public void start_migration_and_return_state_from_databasemigration_when_dbmigration_status_is_NONE() throws Exception {
+    when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
+    when(dialect.supportsMigration()).thenReturn(true);
+    when(databaseMigration.status()).thenReturn(NONE);
+    when(databaseMigration.startedAt()).thenReturn(SOME_DATE);
+
+    underTest.handle(request, response);
+
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_NO_MIGRATION, MESSAGE_MIGRATION_NEEDED));
+  }
+
+  private static String failedMsg(@Nullable String t) {
+    return "Migration failed: " + t + ".<br/> Please check logs.";
+  }
+
+  private static String expectedResponse(String status, String msg) {
+    return "{" +
+      "\"state\":\"" + status + "\"," +
+      "\"message\":\"" + msg + "\"" +
+      "}";
+  }
+
+  private static String expectedResponse(String status, String msg, Date date) {
+    return "{" +
+      "\"state\":\"" + status + "\"," +
+      "\"message\":\"" + msg + "\"," +
+      "\"startedAt\":\"" + DateUtils.formatDateTime(date) + "\"" +
+      "}";
+  }
+}
diff --git a/server/sonar-server/src/test/java/org/sonar/server/platform/ws/MigrateDbActionTest.java b/server/sonar-server/src/test/java/org/sonar/server/platform/ws/MigrateDbActionTest.java
index ecf87a714b9..3f022cb4428 100644
--- a/server/sonar-server/src/test/java/org/sonar/server/platform/ws/MigrateDbActionTest.java
+++ b/server/sonar-server/src/test/java/org/sonar/server/platform/ws/MigrateDbActionTest.java
@@ -48,21 +48,23 @@ import static org.sonar.test.JsonAssert.assertJson;
 
 public class MigrateDbActionTest {
 
-  private static final String UPTODATE_MSG = "Database is up-to-date, no migration needed.";
-  private static final String MIG_NOT_SUPPORTED_MSG = "Upgrade is not supported on embedded database.";
-  private static final String RUNNING_MSG = "Database migration is running.";
   private static final Date SOME_DATE = new Date();
   private static final String SOME_THROWABLE_MSG = "blablabla pop !";
   private static final String DEFAULT_ERROR_MSG = "No failure error";
-  private static final String MIG_SUCCESS_MSG = "Migration succeeded.";
   private static final int CURRENT_VERSION = DatabaseVersion.LAST_VERSION;
   private static final int OLD_VERSION = CURRENT_VERSION - 1;
   private static final int NEWER_VERSION = CURRENT_VERSION + 1;
-  private static final String STATUS_NONE = "NO_MIGRATION";
-  private static final String STATUS_NOT_SUPPORTED = "NOT_SUPPORTED";
-  private static final String STATUS_RUNNING = "MIGRATION_RUNNING";
-  private static final String STATUS_SUCCEEDED = "MIGRATION_SUCCEEDED";
-  private static final String STATUS_FAILED = "MIGRATION_FAILED";
+
+  static final String STATUS_NO_MIGRATION = "NO_MIGRATION";
+  static final String STATUS_NOT_SUPPORTED = "NOT_SUPPORTED";
+  static final String STATUS_MIGRATION_RUNNING = "MIGRATION_RUNNING";
+  static final String STATUS_MIGRATION_FAILED = "MIGRATION_FAILED";
+  static final String STATUS_MIGRATION_SUCCEEDED = "MIGRATION_SUCCEEDED";
+
+  static final String MESSAGE_NO_MIGRATION_ON_EMBEDDED_DATABASE = "Upgrade is not supported on embedded database.";
+  static final String MESSAGE_STATUS_NONE = "Database is up-to-date, no migration needed.";
+  static final String MESSAGE_STATUS_RUNNING = "Database migration is running.";
+  static final String MESSAGE_STATUS_SUCCEEDED = "Migration succeeded.";
 
   DatabaseVersion databaseVersion = mock(DatabaseVersion.class);
   Database database = mock(Database.class);
@@ -97,13 +99,13 @@ public class MigrateDbActionTest {
   }
 
   @Test
-  public void msg_is_operational_and_state_from_databasemigration_when_databaseversion_is_equal_to_currentversion() throws Exception {
+  public void msg_is_operational_and_state_from_database_migration_when_database_version_is_equal_to_current_version() throws Exception {
     when(databaseVersion.getVersion()).thenReturn(CURRENT_VERSION);
     when(databaseMigration.status()).thenReturn(NONE);
 
     underTest.handle(request, response);
 
-    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_NONE, UPTODATE_MSG));
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_NO_MIGRATION, MESSAGE_STATUS_NONE));
   }
 
   // this test will raise a IllegalArgumentException when an unsupported value is added to the Status enum
@@ -118,13 +120,13 @@ public class MigrateDbActionTest {
   }
 
   @Test
-  public void state_from_databasemigration_when_databaseversion_greater_than_currentversion() throws Exception {
+  public void state_from_database_migration_when_databaseversion_greater_than_currentversion() throws Exception {
     when(databaseVersion.getVersion()).thenReturn(NEWER_VERSION);
     when(databaseMigration.status()).thenReturn(NONE);
 
     underTest.handle(request, response);
 
-    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_NONE, UPTODATE_MSG));
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_NO_MIGRATION, MESSAGE_STATUS_NONE));
   }
 
   @Test
@@ -134,11 +136,11 @@ public class MigrateDbActionTest {
 
     underTest.handle(request, response);
 
-    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_NOT_SUPPORTED, MIG_NOT_SUPPORTED_MSG));
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_NOT_SUPPORTED, MESSAGE_NO_MIGRATION_ON_EMBEDDED_DATABASE));
   }
 
   @Test
-  public void state_from_databasemigration_when_dbmigration_status_is_RUNNING() throws Exception {
+  public void state_from_database_migration_when_dbmigration_status_is_RUNNING() throws Exception {
     when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
     when(dialect.supportsMigration()).thenReturn(true);
     when(databaseMigration.status()).thenReturn(RUNNING);
@@ -146,11 +148,11 @@ public class MigrateDbActionTest {
 
     underTest.handle(request, response);
 
-    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_RUNNING, RUNNING_MSG, SOME_DATE));
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_MIGRATION_RUNNING, MESSAGE_STATUS_RUNNING, SOME_DATE));
   }
 
   @Test
-  public void state_from_databasemigration_and_msg_includes_error_when_dbmigration_status_is_FAILED() throws Exception {
+  public void state_from_database_migration_and_msg_includes_error_when_dbmigration_status_is_FAILED() throws Exception {
     when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
     when(dialect.supportsMigration()).thenReturn(true);
     when(databaseMigration.status()).thenReturn(FAILED);
@@ -159,11 +161,11 @@ public class MigrateDbActionTest {
 
     underTest.handle(request, response);
 
-    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_FAILED, failedMsg(SOME_THROWABLE_MSG), SOME_DATE));
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_MIGRATION_FAILED, failedMsg(SOME_THROWABLE_MSG), SOME_DATE));
   }
 
   @Test
-  public void state_from_databasemigration_and_msg_has_default_msg_when_dbmigration_status_is_FAILED() throws Exception {
+  public void state_from_database_migration_and_msg_has_default_msg_when_dbmigration_status_is_FAILED() throws Exception {
     when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
     when(dialect.supportsMigration()).thenReturn(true);
     when(databaseMigration.status()).thenReturn(FAILED);
@@ -172,11 +174,11 @@ public class MigrateDbActionTest {
 
     underTest.handle(request, response);
 
-    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_FAILED, failedMsg(DEFAULT_ERROR_MSG), SOME_DATE));
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_MIGRATION_FAILED, failedMsg(DEFAULT_ERROR_MSG), SOME_DATE));
   }
 
   @Test
-  public void state_from_databasemigration_and_msg_has_default_msg_when_dbmigration_status_is_SUCCEEDED() throws Exception {
+  public void state_from_database_migration_and_msg_has_default_msg_when_dbmigration_status_is_SUCCEEDED() throws Exception {
     when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
     when(dialect.supportsMigration()).thenReturn(true);
     when(databaseMigration.status()).thenReturn(SUCCEEDED);
@@ -184,11 +186,11 @@ public class MigrateDbActionTest {
 
     underTest.handle(request, response);
 
-    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_SUCCEEDED, MIG_SUCCESS_MSG, SOME_DATE));
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_MIGRATION_SUCCEEDED, MESSAGE_STATUS_SUCCEEDED, SOME_DATE));
   }
 
   @Test
-  public void start_migration_and_return_state_from_databasemigration_when_dbmigration_status_is_NONE() throws Exception {
+  public void start_migration_and_return_state_from_database_migration_when_dbmigration_status_is_NONE() throws Exception {
     when(databaseVersion.getVersion()).thenReturn(OLD_VERSION);
     when(dialect.supportsMigration()).thenReturn(true);
     when(databaseMigration.status()).thenReturn(NONE);
@@ -197,7 +199,7 @@ public class MigrateDbActionTest {
     underTest.handle(request, response);
 
     verify(databaseMigration).startIt();
-    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_RUNNING, RUNNING_MSG, SOME_DATE));
+    assertJson(response.outputAsString()).isSimilarTo(expectedResponse(STATUS_MIGRATION_RUNNING, MESSAGE_STATUS_RUNNING, SOME_DATE));
   }
 
   private static String failedMsg(@Nullable String t) {