Handling errors on ffprobe input stream; making sure callback only ge…

…ts called once

lib/ffprobe.js

@@ -92,7 +92,14 @@ module.exports = function(proto) {
     var input, index = null, options = [], callback;
 
     // the last argument should be the callback
-    callback = arguments[arguments.length - 1];
+    var origCallback = arguments[arguments.length - 1];
+    callback = function() {
+      if (origCallback) {
+        var cb = origCallback;
+        origCallback = null;
+        cb.apply(this, arguments);
+      }
+    };
 
     // map the arguments to the correct variable names
     switch (arguments.length) {
@@ -144,11 +151,11 @@ module.exports = function(proto) {
       if (input.isStream) {
         input.source.pipe(ffprobe.stdin);
         input.source.resume();
+
+        input.source.on('error', callback);
       }
 
-      ffprobe.on('error', function(err) {
-        callback(err);
-      });
+      ffprobe.on('error', callback);
 
       // Ensure we wait for captured streams to end before calling callback
       var exitError = null;

test/metadata.test.js

@@ -5,6 +5,7 @@
 var Ffmpeg = require('../index'),
   path = require('path'),
   fs = require('fs'),
+  Readable = require('stream').Readable,
   assert = require('assert'),
   exec = require('child_process').exec,
   testhelper = require('./helpers');
@@ -133,4 +134,20 @@ describe('Metadata', function() {
         done();
       });
   });
+
+  it('should handle errors on stream input to ffprobe', function(done) {
+    var faultyStream = new Readable({objectMode: true});
+    faultyStream._read = function() {};
+    setTimeout(function() {
+      faultyStream.emit('error', new Error('Dummy stream read error'));
+    }, 50);
+
+    new Ffmpeg()
+      .addInput(faultyStream)
+      .ffprobe(function(err, data) {
+        assert.ok(!!err);
+        err.message.should.equal('Dummy stream read error');
+        done();
+      });
+  });
 });