support multiple metrics in a query

src/services/exporter.ts

@@ -16,7 +16,6 @@ import * as path from 'path';
 import * as _ from 'lodash';
 
 const MS_IN_DAY = 24 * 60 * 60 * 1000;
-const TIMESTAMP_COLUMN = 'timestamp';
 
 export class Exporter {
   private exportedRows = 0;
@@ -58,17 +57,17 @@ export class Exporter {
     }
   }
 
+  // TODO: rename `data` to `targets` or `queries`
   public async export(data: Target[], datasourceUrl: string, username: string, from: number, to: number) {
     this.username = username;
 
     this.validateTargets(datasourceUrl, data);
 
-    // console.log('ds', data[0].datasource)
     const targets = data.map(target => {
-      console.log({
+      console.log('target', {
         ...target.datasource,
         url: datasourceUrl
-      })
+      });
       return {
         ...target,
         metric: new QueryConfig(
@@ -83,7 +82,7 @@ export class Exporter {
     });
 
     const datasource = data[0].datasource;
-    this.datasourceRef = data.length === 1 ? { uid: datasource.uid, type: datasource.type } : { uid: 'all', type: 'all' };
+    this.datasourceRef = { uid: datasource.uid, type: datasource.type };
 
     await this.updateStatus(ExportStatus.EXPORTING, 0);
 
@@ -97,8 +96,8 @@ export class Exporter {
 
       console.log(`${day} day: ${from}ms -> ${to}ms`);
 
-      const columns = [TIMESTAMP_COLUMN];
+      let columns = [];
-      const values = {};
+      let values = [];
 
       for(const [index, target] of targets.entries()) {
         const host = new URL(datasourceUrl).origin;
@@ -106,32 +105,15 @@ export class Exporter {
 
         const datasourceMetrics = await queryByConfig(target.metric, datasourceUrl, from, to, apiKey);
 
-        const column = `${target.panel.id}` +
+        columns = datasourceMetrics.columns;
-          `-${target.panel.title.replace(' ', '-')}-${datasourceMetrics.columns[1]}`;
+        values = datasourceMetrics.values;
-
-        columns.push(column);
-
-        for(const row of datasourceMetrics.values) {
-          const [timestamp, value] = row;
-
-          if(values[timestamp] === undefined) {
-            values[timestamp] = new Array(targets.length);
-          }
-          values[timestamp][index] = value;
-        }
       }
 
-      const metricsValues = [];
+      if(columns.length > 0) {
-
+        console.log('values', values);
-      Object.keys(values).forEach(timestamp => {
-        metricsValues.push([timestamp, ...values[timestamp]]);
-      });
-
-      if(metricsValues.length > 0) {
-        console.log(metricsValues)
         this.writeCsv(stream, {
           columns,
-          values: metricsValues,
+          values,
         });
       }
       await this.updateStatus(ExportStatus.EXPORTING, (day + 1) / days);
@@ -141,18 +123,20 @@ export class Exporter {
     stream.end();
   }
 
-  private validateTargets(datasourceUrl, targets: Target[]) {
+  private validateTargets(datasourceUrl: string, targets: Target[]) {
     if(!targets || !Array.isArray(targets)) {
       throw new Error('Incorrect targets format');
     }
 
-    for(const target of targets) {
+    if(targets.length > 1) {
-      const host = new URL(datasourceUrl).origin;
+      throw new Error(`Multiple queries are not supported yet`);
-      const apiKey = apiKeys[host];
+    }
 
-      if(apiKey === undefined || apiKey === '') {
+    const host = new URL(datasourceUrl).origin;
-        throw new Error(`Please configure API key for ${host}`);
+    const apiKey = apiKeys[host];
-      }
+
+    if(apiKey === undefined || apiKey === '') {
+      throw new Error(`Please configure API key for ${host}`);
     }
   }