Integration with grafana datasource kit #2 (#3)

* integrate exporter with new version of datasource-kit

* fix url for getting api key

* Add grafana-datasource-kit to deps

package.json

@@ -15,6 +15,7 @@
     "axios": "^0.18.0",
     "express": "^4.16.3",
     "fast-csv": "^2.4.1",
+    "grafana-datasource-kit": "^0.0.4",
     "moment": "^2.22.1",
     "nodemon": "^1.17.3",
     "ts-loader": "^3.5.0",

src/grafana-datasource-kit/grafana_metric_model.ts

@@ -1,88 +0,0 @@
-export type GrafanaDatasource = {
-  url: string,
-  type: string,
-  params: {
-    db: string,
-    q: string,
-    epoch: string
-  }
-}
-
-export type GrafanaMetricId = string;
-
-export class GrafanaMetric {
-
-  private _metricQuery: MetricQuery = undefined;
-
-  constructor(
-    public datasource: GrafanaDatasource,
-    public targets: any[],
-    public id?: GrafanaMetricId
-  ) {
-    if(datasource === undefined) {
-      throw new Error('datasource is undefined');
-    }
-    if(targets === undefined) {
-      throw new Error('targets is undefined');
-    }
-    if(targets.length === 0) {
-      throw new Error('targets is empty');
-    }
-  }
-
-  public get metricQuery() {
-    if(this._metricQuery === undefined) {
-      this._metricQuery = new MetricQuery(this);
-    }
-    return this._metricQuery;
-  }
-
-  public toObject() {
-    return {
-      datasource: this.datasource,
-      targets: this.targets,
-      _id: this.id
-    };
-  }
-
-  static fromObject(obj: any): GrafanaMetric {
-    if(obj === undefined) {
-      throw new Error('obj is undefined');
-    }
-    return new GrafanaMetric(
-      obj.datasource,
-      obj.targets,
-      obj._id
-    );
-  }
-}
-
-export class MetricQuery {
-
-  private static INFLUX_QUERY_TIME_REGEX = /time >[^A-Z]+/;
-
-  private _queryParts: string[];
-  private _type: string;
-
-  constructor(metric: GrafanaMetric) {
-    this._type = metric.datasource.type;
-    if (this._type !== 'influxdb') {
-      throw new Error(`Queries of type "${metric.datasource.type}" are not supported yet.`);
-    }
-    var queryStr = metric.datasource.params.q;
-    this._queryParts = queryStr.split(MetricQuery.INFLUX_QUERY_TIME_REGEX);
-    if(this._queryParts.length == 1) {
-      throw new Error(
-        `Query "${queryStr}" is not replaced with LIMIT/OFFSET oeprators. Missing time clause.`
-      );
-    }
-    if(this._queryParts.length > 2) {
-      throw new Error(`Query "${queryStr}" has multiple time clauses. Can't parse.`);
-    }
-  }
-
-  getQuery(from: number, to: number, limit: number, offset: number): string {
-    let timeClause = `time >= ${from}ms AND time <= ${to}ms`;
-    return `${this._queryParts[0]} ${timeClause} ${this._queryParts[1]} LIMIT ${limit} OFFSET ${offset}`;
-  }
-}

src/grafana-datasource-kit/grafana_service.ts

@@ -1,70 +0,0 @@
-import { GrafanaMetric } from './grafana_metric_model';
-import { getApiKey } from '../config';
-import { URL } from 'url';
-import axios from 'axios';
-
-
-const CHUNK_SIZE = 50000;
-
-
-/**
- * @param metric to query to Grafana
- * @returns [time, value][] array
- */
-export async function queryByMetric(
-  metric: GrafanaMetric, panelUrl: string, from: number, to: number
-) {
-
-  let datasource = metric.datasource;
-
-  let origin = new URL(panelUrl).origin;
-  let url = `${origin}/${datasource.url}`;
-
-  let params = datasource.params
-  let data = {
-    values: [],
-    columns: []
-  };
-
-  let chunkParams = Object.assign({}, params);
-  while(true) {
-    chunkParams.q = metric.metricQuery.getQuery(from, to, CHUNK_SIZE, data.values.length);
-    var chunk = await queryGrafana(url, chunkParams);
-    let values = chunk.values;
-    data.values = data.values.concat(values);
-    data.columns = chunk.columns;
-
-    if(values.length < CHUNK_SIZE) {
-      // because if we get less that we could, then there is nothing more
-      break;
-    }
-  }
-
-  return data;
-}
-
-async function queryGrafana(url: string, params: any) {
-  let origin = new URL(url).origin;
-  let headers = { Authorization: `Bearer ${getApiKey(origin)}` };
-
-  try {
-    var res = await axios.get(url, { params, headers });
-  } catch (e) {
-    if(e.response.status === 401) {
-      throw new Error('Unauthorized. Check the $HASTIC_API_KEY.');
-    }
-    throw new Error(e.message);
-  }
-
-  if (res.data.results === undefined) {
-    throw new Error('results field is undefined in response.');
-  }
-
-  // TODO: support more than 1 metric (each res.data.results item is a metric)
-  let results = res.data.results[0];
-  if (results.series === undefined) {
-    return [];
-  }
-
-  return results.series[0];
-}

src/target.ts

@@ -1,10 +1,11 @@
-import { queryByMetric } from './grafana-datasource-kit/grafana_service';
+import { queryByMetric, Datasource, Metric } from 'grafana-datasource-kit';
-import { GrafanaDatasource, GrafanaMetric } from './grafana-datasource-kit/grafana_metric_model';
+import { getApiKey } from './config';
 
 import * as csv from 'fast-csv';
 import * as path from 'path';
 import * as fs from 'fs';
 import * as moment from 'moment';
+import { URL } from 'url';
 
 
 const MS_IN_DAY = 24 * 60 * 60 * 1000;
@@ -14,17 +15,17 @@ export class Target {
   private days: number;
   private day: number;
   private csvStream: any;
-  private metric: GrafanaMetric;
+  private metric: Metric;
 
   constructor(
     private panelUrl: string,
     private user: string,
-    datasource: GrafanaDatasource,
+    datasource: Datasource,
     targets: Array<Object>,
     private from: number,
     private to: number
   ) {
-    this.metric = new GrafanaMetric(datasource, targets);
+    this.metric = new Metric(datasource, targets);
   }
 
   public updateStatus(status) {
@@ -64,7 +65,8 @@ export class Target {
 
       console.log(`${this.day} day: ${from}ms -> ${to}ms`);
 
-      let metrics = await queryByMetric(this.metric, this.panelUrl, from, to);
+      let apiKey = getApiKey(new URL(this.panelUrl).origin);
+      let metrics = await queryByMetric(this.metric, this.panelUrl, from, to, apiKey);
 
       if(metrics.values.length > 0) {
         if(metrics !== undefined) {