flink-runtime-web/web-dashboard/src/app/services/metrics.service.ts

/*
 *   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.
 */

import { HttpClient } from '@angular/common/http';
import { Injectable } from '@angular/core';
import { ConfigService } from './config.service';
import { map } from 'rxjs/operators';

@Injectable({
  providedIn: 'root'
})
export class MetricsService {

  constructor(private httpClient: HttpClient, private configService: ConfigService) {
  }

  getAllAvailableMetrics(jobId, vertexId) {
    return this.httpClient.get<Array<{ id: string, value: string }>>(
      `${this.configService.BASE_URL}/jobs/${jobId}/vertices/${vertexId}/metrics`
    );
  }

  getMetrics(jobId, vertexId, listOfMetricName) {
    const metricName = listOfMetricName.join(',');
    return this.httpClient.get<Array<{ id: string, value: string }>>(
      `${this.configService.BASE_URL}/jobs/${jobId}/vertices/${vertexId}/metrics?get=${metricName}`
    ).pipe(
      map(arr => {
        const result = {};
        arr.forEach(item => {
          result[ item.id ] = parseInt(item.value, 10);
        });
        return {
          timestamp: Date.now(),
          values   : result
        };
      }));
  }

  getWatermarks(jobId, vertexId, parallelism) {
    const listOfMetricName = new Array(parallelism).fill(0).map((item, index) => `${index}.currentInputWatermark`);
    return this.getMetrics(jobId, vertexId, listOfMetricName).pipe(map(metrics => {
      let minValue = NaN;
      let lowWatermark = NaN;
      const watermarks = {};
      const ref = metrics.values;
      for (const key in ref) {
        const value = ref[ key ];
        const subTaskIndex = key.replace('.currentInputWatermark', '');
        watermarks[ subTaskIndex ] = value;
        if (isNaN(minValue) || value < minValue) {
          minValue = value;
        }
      }
      if (!isNaN(minValue) && minValue > this.configService.LONG_MIN_VALUE) {
        lowWatermark = minValue;
      } else {
        lowWatermark = NaN;
      }
      return {
        'lowWatermark': lowWatermark,
        'watermarks'  : watermarks
      };
    }));
  }
}