| /* |
| * 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 |
| * <p> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p> |
| * 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.hadoop.ozone.recon.api; |
| |
| import org.apache.hadoop.ozone.recon.MetricsServiceProviderFactory; |
| import org.apache.hadoop.ozone.recon.spi.MetricsServiceProvider; |
| import org.apache.hadoop.ozone.recon.spi.impl.PrometheusServiceProviderImpl; |
| |
| import javax.inject.Inject; |
| import javax.servlet.http.HttpServletResponse; |
| import javax.ws.rs.DefaultValue; |
| import javax.ws.rs.GET; |
| import javax.ws.rs.Path; |
| import javax.ws.rs.PathParam; |
| import javax.ws.rs.Produces; |
| import javax.ws.rs.core.Context; |
| import javax.ws.rs.core.MediaType; |
| import javax.ws.rs.core.Response; |
| import javax.ws.rs.core.UriInfo; |
| |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import java.net.HttpURLConnection; |
| import java.nio.ByteBuffer; |
| import java.nio.channels.Channels; |
| import java.nio.channels.ReadableByteChannel; |
| import java.nio.channels.WritableByteChannel; |
| |
| import static org.apache.hadoop.ozone.recon.spi.impl.PrometheusServiceProviderImpl.PROMETHEUS_INSTANT_QUERY_API; |
| |
| |
| /** |
| * Endpoint to fetch metrics data from Prometheus HTTP endpoint. |
| */ |
| @Path("/metrics") |
| public class MetricsProxyEndpoint { |
| |
| private MetricsServiceProvider metricsServiceProvider; |
| |
| @Inject |
| public MetricsProxyEndpoint( |
| MetricsServiceProviderFactory metricsServiceProviderFactory) { |
| this.metricsServiceProvider = |
| metricsServiceProviderFactory.getMetricsServiceProvider(); |
| } |
| |
| /** |
| * Return a response from the configured metrics endpoint. |
| */ |
| @GET |
| @Produces(MediaType.APPLICATION_JSON) |
| @Path("/{api}") |
| public void getMetricsResponse( |
| @DefaultValue (PROMETHEUS_INSTANT_QUERY_API) @PathParam("api") String api, |
| @Context UriInfo uriInfo, |
| @Context HttpServletResponse httpServletResponse |
| ) throws Exception { |
| if (metricsServiceProvider != null) { |
| HttpURLConnection connection = metricsServiceProvider.getMetricsResponse( |
| api, uriInfo.getRequestUri().getQuery()); |
| InputStream inputStream; |
| if (Response.Status.fromStatusCode(connection.getResponseCode()) |
| .getFamily() == Response.Status.Family.SUCCESSFUL) { |
| inputStream = connection.getInputStream(); |
| } else { |
| // Throw a bad gateway error if HttpResponseCode is not 2xx |
| httpServletResponse.setStatus(HttpServletResponse.SC_BAD_GATEWAY); |
| inputStream = connection.getErrorStream(); |
| } |
| try ( |
| OutputStream outputStream = |
| httpServletResponse.getOutputStream(); |
| ReadableByteChannel inputChannel = |
| Channels.newChannel(inputStream); |
| WritableByteChannel outputChannel = |
| Channels.newChannel(outputStream) |
| ) { |
| final ByteBuffer buffer = ByteBuffer.allocateDirect(16 * 1024); |
| |
| while(inputChannel.read(buffer) != -1) { |
| buffer.flip(); |
| outputChannel.write(buffer); |
| buffer.compact(); |
| } |
| |
| buffer.flip(); |
| |
| while(buffer.hasRemaining()) { |
| outputChannel.write(buffer); |
| } |
| } finally { |
| inputStream.close(); |
| } |
| } else { |
| // Throw a Bad Gateway Error |
| httpServletResponse.sendError(HttpServletResponse.SC_BAD_GATEWAY, |
| "Metrics endpoint is not configured. Configure " + |
| PrometheusServiceProviderImpl.getEndpointConfigKey() + " and " + |
| "try again later."); |
| } |
| } |
| } |