Add count parameter to rules history endpoint.

docs/content/design/coordinator.md

@@ -189,6 +189,10 @@ Returns all rules for a specified datasource and includes default datasource.
 
  Returns audit history of rules for all datasources. default value of interval can be specified by setting `druid.audit.manager.auditHistoryMillis` (1 week if not configured) in coordinator runtime.properties
 
+* `/druid/coordinator/v1/rules/history?count=<n>`
+
+ Returns last <n> entries of audit history of rules for all datasources.
+
 * `/druid/coordinator/v1/rules/{dataSourceName}/history?interval=<interval>`
 
  Returns audit history of rules for a specified datasource. default value of interval can be specified by setting `druid.audit.manager.auditHistoryMillis` (1 week if not configured) in coordinator runtime.properties

server/src/main/java/io/druid/server/http/RulesResource.java

@@ -20,6 +20,7 @@ package io.druid.server.http;
 import com.google.common.collect.ImmutableMap;
 import com.google.inject.Inject;
 
+import io.druid.audit.AuditEntry;
 import io.druid.audit.AuditInfo;
 import io.druid.audit.AuditManager;
 import io.druid.metadata.MetadataRuleManager;
@@ -40,7 +41,6 @@ import javax.ws.rs.QueryParam;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.Response;
-import javax.ws.rs.core.Response.Status;
 
 import java.util.List;
 
@@ -116,37 +116,52 @@ public class RulesResource
       @QueryParam("count") final Integer count
   )
   {
-    Interval theInterval = interval == null ? null : new Interval(interval);
-    if (theInterval == null && count != null) {
     try {
-        return Response.ok(auditManager.fetchAuditHistory(dataSourceName, "rules", count))
+      return Response.ok(getRuleHistory(dataSourceName, interval, count))
                      .build();
-      }
-      catch (IllegalArgumentException e) {
+    } catch (IllegalArgumentException e) {
       return Response.status(Response.Status.BAD_REQUEST)
                      .entity(ImmutableMap.<String, Object>of("error", e.getMessage()))
                      .build();
     }
   }
-    return Response.ok(auditManager.fetchAuditHistory(dataSourceName, "rules", theInterval))
-                   .build();
-  }
 
   @GET
   @Path("/history")
   @Produces(MediaType.APPLICATION_JSON)
   public Response getDatasourceRuleHistory(
-      @QueryParam("interval") final String interval
+      @QueryParam("interval") final String interval,
+      @QueryParam("count") final Integer count
   )
   {
     try {
-      Interval theInterval = interval == null ? null : new Interval(interval);
-      return Response.ok(auditManager.fetchAuditHistory("rules", theInterval))
+      return Response.ok(getRuleHistory(null, interval, count))
+                     .build();
+    } catch (IllegalArgumentException e) {
+      return Response.status(Response.Status.BAD_REQUEST)
+                     .entity(ImmutableMap.<String, Object>of("error", e.getMessage()))
                      .build();
-    }
-    catch (IllegalArgumentException e) {
-      return Response.serverError().entity(ImmutableMap.<String, Object>of("error", e.getMessage())).build();
     }
   }
 
+  private List<AuditEntry> getRuleHistory(
+      final String dataSourceName,
+      final String interval,
+      final Integer count
+  ) throws IllegalArgumentException
+  {
+      if (interval == null && count != null) {
+        if (dataSourceName != null) {
+          return auditManager.fetchAuditHistory(dataSourceName, "rules", count);
+        }
+        return auditManager.fetchAuditHistory("rules", count);
+      }
+
+      Interval theInterval = interval == null ? null : new Interval(interval);
+      if (dataSourceName != null) {
+        return auditManager.fetchAuditHistory(dataSourceName, "rules", theInterval);
+      }
+      return auditManager.fetchAuditHistory("rules", theInterval);
+  }
+
 }

server/src/test/java/io/druid/server/http/RulesResourceTest.java

@@ -152,4 +152,107 @@ public class RulesResourceTest
 
     EasyMock.verify(auditManager);
   }
+
+  @Test
+  public void testGetAllDatasourcesRuleHistoryWithCount()
+  {
+    AuditEntry entry1 = new AuditEntry(
+        "testKey",
+        "testType",
+        new AuditInfo(
+            "testAuthor",
+            "testComment",
+            "127.0.0.1"
+        ),
+        "testPayload",
+        new DateTime("2013-01-02T00:00:00Z")
+    );
+    AuditEntry entry2 = new AuditEntry(
+        "testKey",
+        "testType",
+        new AuditInfo(
+            "testAuthor",
+            "testComment",
+            "127.0.0.1"
+        ),
+        "testPayload",
+        new DateTime("2013-01-01T00:00:00Z")
+    );
+    EasyMock.expect(auditManager.fetchAuditHistory(EasyMock.eq("rules"), EasyMock.eq(2)))
+            .andReturn(ImmutableList.of(entry1, entry2))
+            .once();
+    EasyMock.replay(auditManager);
+
+    RulesResource rulesResource = new RulesResource(databaseRuleManager, auditManager);
+
+    Response response = rulesResource.getDatasourceRuleHistory(null, 2);
+    List<AuditEntry> rulesHistory = (List) response.getEntity();
+    Assert.assertEquals(2, rulesHistory.size());
+    Assert.assertEquals(entry1, rulesHistory.get(0));
+    Assert.assertEquals(entry2, rulesHistory.get(1));
+
+    EasyMock.verify(auditManager);
+  }
+
+  @Test
+  public void testGetAllDatasourcesRuleHistoryWithInterval()
+  {
+    String interval = "P2D/2013-01-02T00:00:00Z";
+    Interval theInterval = new Interval(interval);
+    AuditEntry entry1 = new AuditEntry(
+        "testKey",
+        "testType",
+        new AuditInfo(
+            "testAuthor",
+            "testComment",
+            "127.0.0.1"
+        ),
+        "testPayload",
+        new DateTime("2013-01-02T00:00:00Z")
+    );
+    AuditEntry entry2 = new AuditEntry(
+        "testKey",
+        "testType",
+        new AuditInfo(
+            "testAuthor",
+            "testComment",
+            "127.0.0.1"
+        ),
+        "testPayload",
+        new DateTime("2013-01-01T00:00:00Z")
+    );
+    EasyMock.expect(auditManager.fetchAuditHistory(EasyMock.eq("rules"), EasyMock.eq(theInterval)))
+            .andReturn(ImmutableList.of(entry1, entry2))
+            .once();
+    EasyMock.replay(auditManager);
+
+    RulesResource rulesResource = new RulesResource(databaseRuleManager, auditManager);
+
+    Response response = rulesResource.getDatasourceRuleHistory(interval, null);
+    List<AuditEntry> rulesHistory = (List) response.getEntity();
+    Assert.assertEquals(2, rulesHistory.size());
+    Assert.assertEquals(entry1, rulesHistory.get(0));
+    Assert.assertEquals(entry2, rulesHistory.get(1));
+
+    EasyMock.verify(auditManager);
+  }
+
+  @Test
+  public void testGetAllDatasourcesRuleHistoryWithWrongCount()
+  {
+    EasyMock.expect(auditManager.fetchAuditHistory(EasyMock.eq("rules"), EasyMock.eq(-1)))
+        .andThrow(new IllegalArgumentException("Limit must be greater than zero!"))
+        .once();
+    EasyMock.replay(auditManager);
+
+    RulesResource rulesResource = new RulesResource(databaseRuleManager, auditManager);
+
+    Response response = rulesResource.getDatasourceRuleHistory(null, -1);
+    Map<String, Object> rulesHistory = (Map) response.getEntity();
+    Assert.assertEquals(400, response.getStatus());
+    Assert.assertTrue(rulesHistory.containsKey("error"));
+    Assert.assertEquals("Limit must be greater than zero!", rulesHistory.get("error"));
+
+    EasyMock.verify(auditManager);
+  }
 }