me.j360.trace.server.ZipkinQueryApiV1.java Source code

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Here is the source code for me.j360.trace.server.ZipkinQueryApiV1.java

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/**
 * Copyright 2015-2016 The OpenZipkin Authors
 *
 * Licensed 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 me.j360.trace.server;

import me.j360.trace.core.Codec;
import me.j360.trace.core.Span;
import me.j360.trace.core.storage.QueryRequest;
import me.j360.trace.core.storage.StorageComponent;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.CacheControl;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.context.request.WebRequest;

import java.util.List;
import java.util.concurrent.TimeUnit;

import static me.j360.trace.core.internal.Util.lowerHexToUnsignedLong;
import static org.springframework.http.MediaType.APPLICATION_JSON_VALUE;

/**
 * Implements the json api used by the Zipkin UI
 *
 * See com.twitter.zipkin.query.ZipkinQueryController
 */
@RestController
@RequestMapping("/api/v1")
@CrossOrigin("${zipkin.query.allowed-origins:*}")
public class ZipkinQueryApiV1 {

    @Autowired
    @Value("${zipkin.query.lookback:86400000}")
    int defaultLookback = 86400000; // 7 days in millis

    /** The Cache-Control max-age (seconds) for /api/v1/services and /api/v1/spans */
    @Value("${zipkin.query.names-max-age:300}")
    int namesMaxAge = 300; // 5 minutes
    volatile int serviceCount; // used as a threshold to start returning cache-control headers

    private final StorageComponent storage;

    @Autowired
    public ZipkinQueryApiV1(StorageComponent storage) {
        this.storage = storage; // don't cache spanStore here as it can cause the app to crash!
    }

    @RequestMapping(value = "/dependencies", method = RequestMethod.GET, produces = APPLICATION_JSON_VALUE)
    public byte[] getDependencies(@RequestParam(value = "endTs", required = true) long endTs,
            @RequestParam(value = "lookback", required = false) Long lookback) {
        return Codec.JSON.writeDependencyLinks(
                storage.spanStore().getDependencies(endTs, lookback != null ? lookback : defaultLookback));
    }

    @RequestMapping(value = "/services", method = RequestMethod.GET)
    public ResponseEntity<List<String>> getServiceNames() {
        List<String> serviceNames = storage.spanStore().getServiceNames();
        serviceCount = serviceNames.size();
        return maybeCacheNames(serviceNames);
    }

    @RequestMapping(value = "/spans", method = RequestMethod.GET)
    public ResponseEntity<List<String>> getSpanNames(
            @RequestParam(value = "serviceName", required = true) String serviceName) {
        return maybeCacheNames(storage.spanStore().getSpanNames(serviceName));
    }

    @RequestMapping(value = "/traces", method = RequestMethod.GET, produces = APPLICATION_JSON_VALUE)
    public byte[] getTraces(@RequestParam(value = "serviceName", required = false) String serviceName,
            @RequestParam(value = "spanName", defaultValue = "all") String spanName,
            @RequestParam(value = "annotationQuery", required = false) String annotationQuery,
            @RequestParam(value = "minDuration", required = false) Long minDuration,
            @RequestParam(value = "maxDuration", required = false) Long maxDuration,
            @RequestParam(value = "endTs", required = false) Long endTs,
            @RequestParam(value = "lookback", required = false) Long lookback,
            @RequestParam(value = "limit", required = false) Integer limit) {
        QueryRequest queryRequest = QueryRequest.builder().serviceName(serviceName).spanName(spanName)
                .parseAnnotationQuery(annotationQuery).minDuration(minDuration).maxDuration(maxDuration)
                .endTs(endTs).lookback(lookback != null ? lookback : defaultLookback).limit(limit).build();

        return Codec.JSON.writeTraces(storage.spanStore().getTraces(queryRequest));
    }

    @RequestMapping(value = "/trace/{traceId}", method = RequestMethod.GET, produces = APPLICATION_JSON_VALUE)
    public byte[] getTrace(@PathVariable String traceId, WebRequest request) {
        long id = lowerHexToUnsignedLong(traceId);
        String[] raw = request.getParameterValues("raw"); // RequestParam doesn't work for param w/o value
        List<Span> trace = raw != null ? storage.spanStore().getRawTrace(id) : storage.spanStore().getTrace(id);

        if (trace == null) {
            throw new TraceNotFoundException(traceId, id);
        }
        return Codec.JSON.writeSpans(trace);
    }

    @ExceptionHandler(TraceNotFoundException.class)
    @ResponseStatus(HttpStatus.NOT_FOUND)
    public void notFound() {
    }

    static class TraceNotFoundException extends RuntimeException {
        public TraceNotFoundException(String traceId, long id) {
            super("Cannot find trace for id=" + traceId + ", long value=" + id);
        }
    }

    /**
     * We cache names if there are more than 3 services. This helps people getting started: if we
     * cache empty results, users have more questions. We assume caching becomes a concern when zipkin
     * is in active use, and active use usually implies more than 3 services.
     */
    ResponseEntity<List<String>> maybeCacheNames(List<String> names) {
        ResponseEntity.BodyBuilder response = ResponseEntity.ok();
        if (serviceCount > 3) {
            response.cacheControl(CacheControl.maxAge(namesMaxAge, TimeUnit.SECONDS).mustRevalidate());
        }
        return response.body(names);
    }
}