Debugging Dependencies of Django Project in Eclipse

This is another one of those posts to help myself in the future.  I've got some legacy python projects whose directions only get you a django app running in a virtualenv within eclipse but the dependencies themselves are not debuggable.

It was straightforward once I found the right advice.

If you're like me and have a build that creates a virtualenv with everything installed already by pip and a requirements.txt file.  Here's how to get the environment and eclipse changed so that you can debug any dependency.

#Step 1.  Remove the dependencies files from the virtualenv

This works for mac and uninstalls files that might have spaces in them too

python setup.py install --record files.txt
# inspect files.txt to make sure it looks ok. Then:
tr '\n' '\0' < files.txt | xargs -0 sudo rm -f --

I figured that out after a few different attempts and the best way to do it came from StackOverflow here:  https://stackoverflow.com/a/25209129

 

#Step 2. Add the source folder as an external build dependency on the Python Interpreter Path

 

 

 

 

 

Credit for this step goes to a small sentence buried here:  https://lukeplant.me.uk/blog/posts/eclipse-pydev-and-virtualenv/

 

That's it.  Restart your django server and set a breakpoint inside that internal dependency.

This will save you a ton of time vs. all those import pdb; pdb.set_trace() statements

Drawbacks

This will break the virtualenv from the command line so for things like python manage.py commands.  For those items, I went ahead and set up a second virtualenv.

django manage.py show stacktrace

This is a quick one more to save me time than anything else.

If you're looking for how to get the stacktrace when a django manage.py command crashes, the --traceback option is what you're looking for.

Use it like this:

python manage.py <methodname> --traceback

cURL Example: Post a JSON File with Basic Auth

The web was missing a clear example that showed how to POST a JSON file with Basic Auth.  I love using cURL for it's simplicity when trying out api's and other services that I might want to use and have spent a decent amount of time figuring this particular usage out more than once.  If nothing else, I'll be helping myself next time.

cURL JSON + Basic Auth Samples

In this case, I have a file locally that's contents are the JSON which I want to be the payload of the POST.  Note that I do not want to POST the file as with a multi-part form upload.

curl -X POST -d @pathtofile https://user:pass@www.samplesite.com

Depending on the service you are calling, you might also need to set the Content-Type and encoding.

curl --header "Content-Type: application/json;charset=UTF-8" -X POST -d @pathtofile https://user:pass@www.samplesite.com

Finally, for troubleshooting, I've found it useful to either use the verbose -v for inspecting headers or --trace-ascii /dev/stdout for seeing the content of the request

curl -X POST -d @pathtofile https://user:pass@www.samplesite.com -v

curl -X POST -d @pathtofile https://user:pass@www.samplesite.com --trace-ascii /dev/stdout

Sample Output of --trace-ascii /dev/stdout command

== Info: Trying aa.xx.dd.bb...
== Info: Connected to xyz.abcd.com (aa.xx.dd.bb) port 443 (#0)
== Info: TLS 1.2 connection using TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256
== Info: Server certificate: xyz.abcd.com
== Info: Server auth using Basic with user 'admin'
=> Send header, 241 bytes (0xf1)
0000: POST /demo HTTP/1.1
0031: Host: xyz.abcd.com
004f: Authorization: Basic Z3JlZW5oYXRhZG1pbjoxMjNBZG1pbiE=
0086: User-Agent: curl/7.43.0
009f: Accept: */*
00ac: Content-Type: application/json;charset=UTF-8
00da: Content-Length: 596
00ef:
=> Send data, 596 bytes (0x254)
0000: { "Students": [{ "MIS_ID": 201073, "Forename": "Test", "Surname
0040: ": "Tester", "Email": "xyz.abcd@gmail.com", "YearGroup": "6
0080: ", "Gender": "M", "Password": "Ab@12" }, { "MIS_ID": 161201, "Fo
00c0: rename": "Tester", "Surname": "Test", "Email": "xyz.abcd@gm
0100: ail.com", "YearGroup": "6", "Gender": "F", "Password": "Ab@12
0140: " }], "Staff": [{ "TeacherID": 220380, "Title": "Mrs", "Forename
0180: ": "Test", "Surname": "Tester", "Email": "xyz.abcd@gmail.
01c0: com" }], "Groups": [{ "GroupID": 63, "GroupName": "6A Science", "
0200: GroupType": "Class", "GroupDescription": "6A Science", "PrimaryS
0240: taffId": 220380 }] }
== Info: upload completely sent off: 596 out of 596 bytes
<= Recv header, 17 bytes (0x11)
0000: HTTP/1.1 200 OK
<= Recv header, 52 bytes (0x34)
0000: Cache-Control: no-cache, no-store, must-revalidate
<= Recv header, 47 bytes (0x2f)
0000: Content-Type: application/json; charset=utf-8
<= Recv header, 37 bytes (0x25)
0000: Date: Wed, 09 Dec 2015 16:02:52 GMT
<= Recv header, 40 bytes (0x28)
0000: Expires: Thu, 19 Jun 1980 19:19:19 GMT
<= Recv header, 18 bytes (0x12)
0000: Pragma: no-cache
<= Recv header, 15 bytes (0xf)
0000: Server: nginx
<= Recv header, 45 bytes (0x2d)
0000: Strict-Transport-Security: max-age=31536000
<= Recv header, 23 bytes (0x17)
0000: Vary: Accept-Encoding
<= Recv header, 20 bytes (0x14)
0000: Content-Length: 25
<= Recv header, 24 bytes (0x18)
0000: Connection: keep-alive
<= Recv header, 2 bytes (0x2)
0000:
<= Recv data, 25 bytes (0x19)
0000: {"i":"4T7hz8tz8KU7ms2rz"}
== Info: Connection #0 to host xyz.abcd.com left intact
{"i":"4T7hz8tz8KU7ms2rz"}%