HDDS-8214. Recon - OM DB Insights - Key Level Info

hadoop-ozone/recon/src/main/java/org/apache/hadoop/ozone/recon/api/ContainerEndpoint.java

@@ -421,7 +421,7 @@ public Response getUnhealthyContainers(
    * }
    * @param limit limits the number of deleted containers
    * @param prevKey previous container Id to skip
-   * @return Response of delete containers.
+   * @return Response of deleted containers.
    */
   @GET
   @Path("/deleted")
@@ -566,4 +566,76 @@ public Response getContainerMisMatchInsights() {
     }
     return Response.ok(containerDiscrepancyInfoList).build();
   }
+
+  /** This API retrieves set of deleted containers in SCM which are present
+   * in OM to find out list of keys mapped to such DELETED state containers.
+   *
+   * limit - limits the number of such SCM DELETED containers present in OM.
+   * prevKey - Skip containers till it seeks correctly to the previous
+   * containerId.
+   * Sample API Response:
+   * [
+   *   {
+   *     "containerId": 2,
+   *     "numberOfKeys": 2,
+   *     "pipelines": []
+   *   }
+   * ]
+   */
+  @GET
+  @Path("/mismatch/deleted")
+  public Response getOmContainersDeletedInSCM(
+      @DefaultValue(DEFAULT_FETCH_COUNT) @QueryParam(RECON_QUERY_LIMIT)
+      int limit,
+      @DefaultValue(PREV_CONTAINER_ID_DEFAULT_VALUE)
+      @QueryParam(RECON_QUERY_PREVKEY) long prevKey) {
+    if (prevKey < 0) {
+      // Send back an empty response
+      return Response.status(Response.Status.NOT_ACCEPTABLE).build();
+    }
+    List<ContainerDiscrepancyInfo> containerDiscrepancyInfoList =
+        new ArrayList<>();
+    try {
+      Map<Long, ContainerMetadata> omContainers =
+          reconContainerMetadataManager.getContainers(limit, prevKey);
+
+      List<Long> deletedStateSCMContainerIds =
+          containerManager.getContainers().stream()
+              .filter(containerInfo -> (containerInfo.getState() ==
+                  HddsProtos.LifeCycleState.DELETED))
+              .map(containerInfo -> containerInfo.getContainerID()).collect(
+                  Collectors.toList());
+
+      List<Map.Entry<Long, ContainerMetadata>>
+          omContainersDeletedInSCM =
+          omContainers.entrySet().stream().filter(containerMetadataEntry ->
+                  (deletedStateSCMContainerIds.contains(
+                      containerMetadataEntry.getKey())))
+              .collect(
+                  Collectors.toList());
+
+      omContainersDeletedInSCM.forEach(
+          containerMetadataEntry -> {
+            ContainerDiscrepancyInfo containerDiscrepancyInfo =
+                new ContainerDiscrepancyInfo();
+            containerDiscrepancyInfo.setContainerID(
+                containerMetadataEntry.getKey());
+            containerDiscrepancyInfo.setNumberOfKeys(
+                containerMetadataEntry.getValue().getNumberOfKeys());
+            containerDiscrepancyInfo.setPipelines(
+                containerMetadataEntry.getValue()
+                    .getPipelines());
+            containerDiscrepancyInfoList.add(containerDiscrepancyInfo);
+          });
+    } catch (IOException ex) {
+      throw new WebApplicationException(ex,
+          Response.Status.INTERNAL_SERVER_ERROR);
+    } catch (IllegalArgumentException e) {
+      throw new WebApplicationException(e, Response.Status.BAD_REQUEST);
+    } catch (Exception ex) {
+      throw new WebApplicationException(ex,
+          Response.Status.INTERNAL_SERVER_ERROR);
+    }
+    return Response.ok(containerDiscrepancyInfoList).build();
+  }
 }