feat: allow custom file name generator function

fixes #59

Author: Michael Weibel

README.md

@@ -286,6 +286,18 @@ Replay.recordResponseControl = {
 };
 ```
 
+The generated fixtures by default are named using a uid generator function and it's reasonably safe for them to be unique.
+However because they're only a bunch of numbers, it can be sometimes painful to find which fixture belongs to what request.
+
+You can supply a custom filename generator function if you wish to change that:
+
+```javascript
+Replay.filenameGenerator = function(request) {
+  // just an example, you may want to improve that
+  return `${slugify(`${request.method.toUpperCase()}_${request.url.path}`)}_${Date.now()}${Math.floor(Math.random() * 100000)}`;
+};
+```
+
 
 ## Geeking
 

package-lock.json

@@ -51,7 +51,8 @@
     "gulp-sourcemaps": "^2.6.4",
     "gulp-util": "^3.0.7",
     "mocha": "^5.1.1",
-    "request": "^2.85.0"
+    "request": "^2.85.0",
+    "slugify": "^1.3.4"
   },
   "repository": {
     "type": "git",

package.json

@@ -209,7 +209,7 @@ module.exports = class Catalog {
     matchers.push(matcher);
     const requestHeaders = this.settings.headers;
 
-    const uid       = `${Date.now()}${Math.floor(Math.random() * 100000)}`;
+    const uid       = this.settings.filenameGenerator(request);
     const tmpfile   = `${this.getFixturesDir()}/node-replay.${uid}`;
     const pathname  = `${this.getFixturesDir()}/${host.replace(':', '-')}`;
 

src/catalog.js

@@ -71,6 +71,9 @@ class Replay extends EventEmitter {
     // Dropp connections to these servers
     this._dropped     = new Set();
 
+    this.filenameGenerator = function() {
+      return `${Date.now()}${Math.floor(Math.random() * 100000)}`
+    };
     this.catalog = new Catalog(this);
     this.headers = MATCH_HEADERS;
 

src/index.js

@@ -5,6 +5,7 @@ const HTTP    = require('http');
 const HTTPS   = require('https');
 const Async   = require('async');
 const Request = require('request');
+const slugify = require('slugify');
 const Replay  = require('../src');
 
 
@@ -351,6 +352,65 @@ describe('Replay', function() {
 
   });
 
+  describe('custom filenameGenerator', function() {
+    const fixturesDir = `${__dirname}/fixtures/127.0.0.1-${HTTP_PORT}`;
+
+    before(setup);
+
+    before(function() {
+      Replay.mode = 'record';
+      Replay.reset('127.0.0.1');
+      Replay.filenameGenerator = function(request) {
+        return slugify(`${request.method.toUpperCase()}_${request.url.path}`);
+      };
+    });
+
+    it('should create fixture files with custom names', function(done) {
+      const requests = [
+        { name: 'Lorem', extra: 'Ipsum'},
+        { name: 'Dolor', extra: 'Sit'}
+      ].map(function(query) {
+        return function(callback) {
+          Request.get({
+            url:    `http://127.0.0.1:${HTTP_PORT}/query`,
+            qs:     query,
+            headers: {
+              'X-Some-Header': 'Test'
+            },
+            json:   true
+          }, function(error, response, body) {
+            if (error)
+              callback(error);
+            else
+              try {
+                assert.deepEqual(body, query);
+                callback(null, query);
+              } catch (error) {
+                callback(error);
+              }
+          });
+        };
+      });
+
+      Async.series(requests, function(error) {
+        if (error)
+          done(error);
+        else {
+          // fixtures should be written now
+          Replay.mode = 'replay';
+          Async.series(requests, done);
+        }
+      });
+    });
+
+    after(function() {
+      if (File.existsSync(fixturesDir)) {
+        for (let file of File.readdirSync(fixturesDir))
+          File.unlinkSync(`${fixturesDir}/${file}`);
+        File.rmdirSync(fixturesDir);
+      }
+    });
+  });
 
   describe('recording gzipped replay', function() {
     const fixturesDir = `${__dirname}/fixtures/127.0.0.1-${HTTP_PORT}`;