LeeCroft at 19:49, 19 March 2016

2016-03-19T19:49:37Z

← Older revision		Revision as of 19:49, 19 March 2016
Line 118:		Line 118:
	***This is to get a round a bug where the file buffer was not preserved in its Buffer format during storage in memory		***This is to get a round a bug where the file buffer was not preserved in its Buffer format during storage in memory

	===Instructor comments===		==Instructor comments==

	In class I had trouble with downloading the file. Everything worked except that the downloaded file became [Object object].		In class I had trouble with downloading the file. Everything worked except that the downloaded file became [Object object].

LeeCroft at 19:48, 19 March 2016

2016-03-19T19:48:15Z

@@ Line 3: / Line 3: @@
 The video from the lecture given on March 15, 2016 [http://homeostasis.scs.carleton.ca/~soma/webfund-2016w/lectures/comp2406-2016w-lec17-15Mar2016.mp4 is now available].
-==Notes==
+==Student Notes==
 ===Instructor comments===

Soma: Created page with "==Video== The video from the lecture given on March 15, 2016 [http://homeostasis.scs.carleton.ca/~soma/webfund-2016w/lectures/comp2406-2016w-lec17-15Mar2016.mp4 is now availa..."

2016-03-15T21:58:38Z

Created page with "==Video== The video from the lecture given on March 15, 2016 [http://homeostasis.scs.carleton.ca/~soma/webfund-2016w/lectures/comp2406-2016w-lec17-15Mar2016.mp4 is now availa..."

New page

==Video==

The video from the lecture given on March 15, 2016 [http://homeostasis.scs.carleton.ca/~soma/webfund-2016w/lectures/comp2406-2016w-lec17-15Mar2016.mp4 is now available].

==Notes==

===Instructor comments===

In class I had trouble with downloading the file. Everything worked except that the downloaded file became [Object object].

The problematic line was this, in downloadFile()

response = allFiles[i].buffer.toString('utf8');

This line '''should''' work because when we stored the file in uploadText() it did. But in between (perhaps when stored as a session property) it was changed.

Before, we had:

{ '0': 123,
'1': 10,
'2': 32,
'3': 32,
...
}

But now this got changed into:

{ type: 'Buffer',
data:
[ 123,
10,
32,
32,
...
]
}

The former is of type Buffer (as reported by Buffer.isBuffer()), the latter is not.

While this is strange behavior, the fix is easy:

response = Buffer(allFiles[i].buffer.data).toString('utf8');

This is definitely a bug in node or express. If anyone wants to try isolating this bug and reporting it, let me know!

==Code==

[http://homeostasis.scs.carleton.ca/~soma/webfund-2016w/code/upload-demo-class.zip upload-demo with working download button]

WebFund 2016W Lecture 17 - Revision history

LeeCroft at 19:49, 19 March 2016

LeeCroft at 19:48, 19 March 2016

Soma: Created page with "==Video== The video from the lecture given on March 15, 2016 [http://homeostasis.scs.carleton.ca/~soma/webfund-2016w/lectures/comp2406-2016w-lec17-15Mar2016.mp4 is now availa..."