/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.kafka.connect.runtime.rest.resources;
import com.fasterxml.jackson.core.type.TypeReference;
import org.apache.kafka.connect.runtime.ConnectorConfig;
import org.apache.kafka.connect.runtime.Herder;
import org.apache.kafka.connect.runtime.distributed.RebalanceNeededException;
import org.apache.kafka.connect.runtime.distributed.RequestTargetException;
import org.apache.kafka.connect.runtime.rest.RestServer;
import org.apache.kafka.connect.runtime.rest.entities.ConnectorInfo;
import org.apache.kafka.connect.runtime.rest.entities.ConnectorStateInfo;
import org.apache.kafka.connect.runtime.rest.entities.CreateConnectorRequest;
import org.apache.kafka.connect.runtime.rest.entities.TaskInfo;
import org.apache.kafka.connect.runtime.rest.errors.ConnectRestException;
import org.apache.kafka.connect.util.ConnectorTaskId;
import org.apache.kafka.connect.util.FutureCallback;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.servlet.ServletContext;
import javax.ws.rs.BadRequestException;
import javax.ws.rs.Consumes;
import javax.ws.rs.DELETE;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.PUT;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.QueryParam;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.UriBuilder;
import java.net.URI;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
@Path("/connectors")
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public class ConnectorsResource {
private static final Logger log = LoggerFactory.getLogger(ConnectorsResource.class);
// TODO: This should not be so long. However, due to potentially long rebalances that may have to wait a full
// session timeout to complete, during which we cannot serve some requests. Ideally we could reduce this, but
// we need to consider all possible scenarios this could fail. It might be ok to fail with a timeout in rare cases,
// but currently a worker simply leaving the group can take this long as well.
private static final long REQUEST_TIMEOUT_MS = 90 * 1000;
private final Herder herder;
@javax.ws.rs.core.Context
private ServletContext context;
public ConnectorsResource(Herder herder) {
this.herder = herder;
}
@GET
@Path("/")
public Collection<String> listConnectors(final @QueryParam("forward") Boolean forward) throws Throwable {
FutureCallback<Collection<String>> cb = new FutureCallback<>();
herder.connectors(cb);
return completeOrForwardRequest(cb, "/connectors", "GET", null, new TypeReference<Collection<String>>() {
}, forward);
}
@POST
@Path("/")
public Response createConnector(final @QueryParam("forward") Boolean forward,
final CreateConnectorRequest createRequest) throws Throwable {
String name = createRequest.name();
if (name.contains("/")) {
throw new BadRequestException("connector name should not contain '/'");
}
Map<String, String> configs = createRequest.config();
if (!configs.containsKey(ConnectorConfig.NAME_CONFIG))
configs.put(ConnectorConfig.NAME_CONFIG, name);
FutureCallback<Herder.Created<ConnectorInfo>> cb = new FutureCallback<>();
herder.putConnectorConfig(name, configs, false, cb);
Herder.Created<ConnectorInfo> info = completeOrForwardRequest(cb, "/connectors", "POST", createRequest,
new TypeReference<ConnectorInfo>() { }, new CreatedConnectorInfoTranslator(), forward);
return Response.created(URI.create("/connectors/" + name)).entity(info.result()).build();
}
@GET
@Path("/{connector}")
public ConnectorInfo getConnector(final @PathParam("connector") String connector,
final @QueryParam("forward") Boolean forward) throws Throwable {
FutureCallback<ConnectorInfo> cb = new FutureCallback<>();
herder.connectorInfo(connector, cb);
return completeOrForwardRequest(cb, "/connectors/" + connector, "GET", null, forward);
}
@GET
@Path("/{connector}/config")
public Map<String, String> getConnectorConfig(final @PathParam("connector") String connector,
final @QueryParam("forward") Boolean forward) throws Throwable {
FutureCallback<Map<String, String>> cb = new FutureCallback<>();
herder.connectorConfig(connector, cb);
return completeOrForwardRequest(cb, "/connectors/" + connector + "/config", "GET", null, forward);
}
@GET
@Path("/{connector}/status")
public ConnectorStateInfo getConnectorStatus(final @PathParam("connector") String connector) throws Throwable {
return herder.connectorStatus(connector);
}
@PUT
@Path("/{connector}/config")
public Response putConnectorConfig(final @PathParam("connector") String connector,
final @QueryParam("forward") Boolean forward,
final Map<String, String> connectorConfig) throws Throwable {
FutureCallback<Herder.Created<ConnectorInfo>> cb = new FutureCallback<>();
String includedName = connectorConfig.get(ConnectorConfig.NAME_CONFIG);
if (includedName != null) {
if (!includedName.equals(connector))
throw new BadRequestException("Connector name configuration (" + includedName + ") doesn't match connector name in the URL (" + connector + ")");
} else {
connectorConfig.put(ConnectorConfig.NAME_CONFIG, connector);
}
herder.putConnectorConfig(connector, connectorConfig, true, cb);
Herder.Created<ConnectorInfo> createdInfo = completeOrForwardRequest(cb, "/connectors/" + connector + "/config",
"PUT", connectorConfig, new TypeReference<ConnectorInfo>() { }, new CreatedConnectorInfoTranslator(), forward);
Response.ResponseBuilder response;
if (createdInfo.created())
response = Response.created(URI.create("/connectors/" + connector));
else
response = Response.ok();
return response.entity(createdInfo.result()).build();
}
@POST
@Path("/{connector}/restart")
public void restartConnector(final @PathParam("connector") String connector,
final @QueryParam("forward") Boolean forward) throws Throwable {
FutureCallback<Void> cb = new FutureCallback<>();
herder.restartConnector(connector, cb);
completeOrForwardRequest(cb, "/connectors/" + connector + "/restart", "POST", null, forward);
}
@PUT
@Path("/{connector}/pause")
public Response pauseConnector(@PathParam("connector") String connector) {
herder.pauseConnector(connector);
return Response.accepted().build();
}
@PUT
@Path("/{connector}/resume")
public Response resumeConnector(@PathParam("connector") String connector) {
herder.resumeConnector(connector);
return Response.accepted().build();
}
@GET
@Path("/{connector}/tasks")
public List<TaskInfo> getTaskConfigs(final @PathParam("connector") String connector,
final @QueryParam("forward") Boolean forward) throws Throwable {
FutureCallback<List<TaskInfo>> cb = new FutureCallback<>();
herder.taskConfigs(connector, cb);
return completeOrForwardRequest(cb, "/connectors/" + connector + "/tasks", "GET", null, new TypeReference<List<TaskInfo>>() {
}, forward);
}
@POST
@Path("/{connector}/tasks")
public void putTaskConfigs(final @PathParam("connector") String connector,
final @QueryParam("forward") Boolean forward,
final List<Map<String, String>> taskConfigs) throws Throwable {
FutureCallback<Void> cb = new FutureCallback<>();
herder.putTaskConfigs(connector, taskConfigs, cb);
completeOrForwardRequest(cb, "/connectors/" + connector + "/tasks", "POST", taskConfigs, forward);
}
@GET
@Path("/{connector}/tasks/{task}/status")
public ConnectorStateInfo.TaskState getTaskStatus(final @PathParam("connector") String connector,
final @PathParam("task") Integer task) throws Throwable {
return herder.taskStatus(new ConnectorTaskId(connector, task));
}
@POST
@Path("/{connector}/tasks/{task}/restart")
public void restartTask(final @PathParam("connector") String connector,
final @PathParam("task") Integer task,
final @QueryParam("forward") Boolean forward) throws Throwable {
FutureCallback<Void> cb = new FutureCallback<>();
ConnectorTaskId taskId = new ConnectorTaskId(connector, task);
herder.restartTask(taskId, cb);
completeOrForwardRequest(cb, "/connectors/" + connector + "/tasks/" + task + "/restart", "POST", null, forward);
}
@DELETE
@Path("/{connector}")
public void destroyConnector(final @PathParam("connector") String connector,
final @QueryParam("forward") Boolean forward) throws Throwable {
FutureCallback<Herder.Created<ConnectorInfo>> cb = new FutureCallback<>();
herder.deleteConnectorConfig(connector, cb);
completeOrForwardRequest(cb, "/connectors/" + connector, "DELETE", null, forward);
}
// Wait for a FutureCallback to complete. If it succeeds, return the parsed response. If it fails, try to forward the
// request to the leader.
private <T, U> T completeOrForwardRequest(FutureCallback<T> cb,
String path,
String method,
Object body,
TypeReference<U> resultType,
Translator<T, U> translator,
Boolean forward) throws Throwable {
try {
return cb.get(REQUEST_TIMEOUT_MS, TimeUnit.MILLISECONDS);
} catch (ExecutionException e) {
Throwable cause = e.getCause();
if (cause instanceof RequestTargetException) {
if (forward == null || forward) {
// the only time we allow recursive forwarding is when no forward flag has
// been set, which should only be seen by the first worker to handle a user request.
// this gives two total hops to resolve the request before giving up.
boolean recursiveForward = forward == null;
RequestTargetException targetException = (RequestTargetException) cause;
String forwardUrl = UriBuilder.fromUri(targetException.forwardUrl())
.path(path)
.queryParam("forward", recursiveForward)
.build()
.toString();
log.debug("Forwarding request {} {} {}", forwardUrl, method, body);
return translator.translate(RestServer.httpRequest(forwardUrl, method, body, resultType));
} else {
// we should find the right target for the query within two hops, so if
// we don't, it probably means that a rebalance has taken place.
throw new ConnectRestException(Response.Status.CONFLICT.getStatusCode(),
"Cannot complete request because of a conflicting operation (e.g. worker rebalance)");
}
} else if (cause instanceof RebalanceNeededException) {
throw new ConnectRestException(Response.Status.CONFLICT.getStatusCode(),
"Cannot complete request momentarily due to stale configuration (typically caused by a concurrent config change)");
}
throw cause;
} catch (TimeoutException e) {
// This timeout is for the operation itself. None of the timeout error codes are relevant, so internal server
// error is the best option
throw new ConnectRestException(Response.Status.INTERNAL_SERVER_ERROR.getStatusCode(), "Request timed out");
} catch (InterruptedException e) {
throw new ConnectRestException(Response.Status.INTERNAL_SERVER_ERROR.getStatusCode(), "Request interrupted");
}
}
private <T> T completeOrForwardRequest(FutureCallback<T> cb, String path, String method, Object body,
TypeReference<T> resultType, Boolean forward) throws Throwable {
return completeOrForwardRequest(cb, path, method, body, resultType, new IdentityTranslator<T>(), forward);
}
private <T> T completeOrForwardRequest(FutureCallback<T> cb, String path, String method,
Object body, Boolean forward) throws Throwable {
return completeOrForwardRequest(cb, path, method, body, null, new IdentityTranslator<T>(), forward);
}
private interface Translator<T, U> {
T translate(RestServer.HttpResponse<U> response);
}
private static class IdentityTranslator<T> implements Translator<T, T> {
@Override
public T translate(RestServer.HttpResponse<T> response) {
return response.body();
}
}
private static class CreatedConnectorInfoTranslator implements Translator<Herder.Created<ConnectorInfo>, ConnectorInfo> {
@Override
public Herder.Created<ConnectorInfo> translate(RestServer.HttpResponse<ConnectorInfo> response) {
boolean created = response.status() == 201;
return new Herder.Created<>(created, response.body());
}
}
}