control-c doesn't lose all your progress

Author: blackmad

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@blackmad/api-diff",
-  "version": "1.0.29",
+  "version": "1.0.31",
   "description": "",
   "main": "index.js",
   "scripts": {
@@ -28,6 +28,7 @@
   },
   "homepage": "https://github.com/radarlabs/api-diff#readme",
   "dependencies": {
+    "@types/bluebird": "^3.5.32",
     "@types/cli-progress": "^3.8.0",
     "axios": "^0.19.2",
     "axios-retry": "^3.1.8",
@@ -45,6 +46,7 @@
     "stats-lite": "^2.2.0",
     "table": "^5.4.6",
     "winston": "^3.3.3",
+    "wtfnode": "^0.8.1",
     "yargs": "^15.1.0"
   },
   "devDependencies": {

src/api-diff/api-diff.ts

@@ -1,7 +1,7 @@
 #!/usr/bin/env node
 /* eslint-disable no-console */
 
-import * as Bluebird from 'bluebird';
+import Bluebird from 'bluebird';
 import * as jsondiffpatch from 'jsondiffpatch';
 import { AxiosResponse } from 'axios';
 import jp from 'jsonpath';
@@ -112,9 +112,15 @@ async function compareQueries({
   const oldStatusCodes: Record<number, number> = {};
   const newStatusCodes: Record<number, number> = {};
 
-  await Bluebird.map(
+  let isCancelled = false;
+
+  const queriesPromise = Bluebird.map(
     queries,
     async (query: Query) => {
+      if (isCancelled) {
+        return;
+      }
+
       const change = await compareQuery({
         oldApiEnv,
         newApiEnv,
@@ -142,6 +148,16 @@ async function compareQueries({
     },
     { concurrency: argv.concurrency },
   );
+
+  process.on('SIGINT', () => {
+    console.error('Caught interrupt signal, stopping early ...');
+    isCancelled = true;
+  });
+
+  await queriesPromise.catch(() => {
+    console.error('Aborted diff early ... saving result ...');
+  });
+
   formatter.finished({
     old: {
       responseTimes: oldResponseTimes,
@@ -151,7 +167,7 @@ async function compareQueries({
       responseTimes: newResponseTimes,
       statusCodes: newStatusCodes,
     },
-  });
+  }).then(() => process.exit(0));
 }
 
 /** Main logic - parses command line, creates a formatter, runs queries and

src/api-diff/formatters/compare-formatter.ts

@@ -94,16 +94,17 @@ export abstract class CompareFormatter {
   }
 
   /** Called when all queries are finished running */
-  abstract onFinished(finishedStats: FinishedStats): void;
+  abstract onFinished(finishedStats: FinishedStats): Promise<void>;
 
   /**
    * Called when all queries are finished running
    *
    * @param finishedStats
+   * @returns {Promise<void>} fulfilled on output finished
    */
-  finished(finishedStats: FinishedStats): void {
+  finished(finishedStats: FinishedStats): Promise<void> {
     console.error(`DONE. ${this.numQueriesChanged}/${this.numQueriesRun} changed`);
-    this.onFinished(finishedStats);
+    return this.onFinished(finishedStats);
   }
 
   /**
@@ -119,13 +120,16 @@ export abstract class CompareFormatter {
    * Helper to deal with output redirection
    *
    * @param {string} s string to output
+   * @returns {Promise<void>} promise on finished
    */
-  write(s: string): void {
-    if (this.outputStream) {
-      this.outputStream.write(s);
-    } else {
-      process.stdout.write(s);
-    }
+  write(s: string): Promise<void> {
+    const stream = this.outputStream || process.stdout;
+    return new Promise((resolve, reject) => {
+      stream.write(s);
+      stream.end();
+      stream.on('finish', () => { resolve(); });
+      stream.on('error', reject);
+    });
   }
 
   constructor({

src/api-diff/formatters/console-formatter.ts

@@ -45,7 +45,7 @@ export default class ConsoleFormatter extends CompareFormatter {
     (jsondiffpatch.console as any).log(change.delta);
   }
 
-  onFinished(finishedStats: FinishedStats): void {
+  onFinished(finishedStats: FinishedStats): Promise<void> {
     this.writeln(`Elapsed: ${(Date.now() - this.startDate.getTime()) / 1000} seconds`);
 
     this.writeln('');
@@ -78,5 +78,7 @@ export default class ConsoleFormatter extends CompareFormatter {
     });
 
     this.writeln(table(statusCodesTable));
+
+    return Promise.resolve();
   }
 }

src/api-diff/formatters/html-formatter.ts

@@ -5,10 +5,10 @@ import { FinishedStats } from './compare-formatter';
 import JsonFormatter from './json-formatter';
 
 export default class HtmlFormatter extends JsonFormatter {
-  onFinished(finishedStats: FinishedStats): void {
+  onFinished(finishedStats: FinishedStats): Promise<void> {
     const filePath = path.join(__dirname, 'compare.template');
     const html = fs.readFileSync(filePath).toString();
-    this.write(
+    return this.write(
       html.replace('let json = {};', `let json = ${JSON.stringify(this.finishedDict(finishedStats), null, 2)};`),
     );
   }

src/api-diff/formatters/json-formatter.ts

@@ -70,7 +70,7 @@ export default class JsonFormatter extends CompareFormatter {
     };
   }
 
-  onFinished(finishedStats: FinishedStats): void {
-    this.write(JSON.stringify(this.finishedDict(finishedStats), null, 2));
+  onFinished(finishedStats: FinishedStats): Promise<void> {
+    return this.write(JSON.stringify(this.finishedDict(finishedStats), null, 2));
   }
 }