Dockerize

[MikeTheCanuck]

Summary

This enables the Django app to run in a Docker container.

I have tested these changes both with and without Docker, to ensure that the Swagger styling appears in both non-Docker and Docker container contexts.

Testing

git pull
git checkout dockerize
cd budget_proj
docker-compose up --build
Browse to an endpoint e.g. http://localhost:8000/kpm/
You should see the Swagger-styled response from the endpoint

Next Steps After Merge

I will address the Travis failures once this has been merged. Travis testing results have been inconclusive given the flurry of activity in these files between branches and merges.

[jimtyhurst]

I see this error message:

$ docker-compose up --build
...
Successfully built fd79068dd2db
Recreating budgetproj_web_1
Attaching to budgetproj_web_1
web_1  | Traceback (most recent call last):
...
web_1  | ImportError: No module named 'rest_framework_swagger'
web_1  | [2017-03-08 22:59:54 +0000] [12] [INFO] Worker exiting (pid: 12)
web_1  | [2017-03-08 22:59:54 +0000] [9] [INFO] Shutting down: Master
web_1  | [2017-03-08 22:59:54 +0000] [9] [INFO] Reason: Worker failed to boot.
budgetproj_web_1 exited with code 3

However, when I run outside of Docker container:

$ ./manage.py runserver

I see Swagger pages at http://localhost:8000/.

Things I checked:

• pip install -r requirements.txt inside the Dockerfile.
• django-rest-swagger==2.1.1 in the requirements.txt file.
• rest_framework_swagger referenced inside INSTALLED_APPS in settings.py.
• My local environment is running with budget_venv and I did pip install -r requirements.txt there, but I assume the error is from an unfulfilled import in the container.

I am not sure why I get the error when running docker-compose. I will look at it more tonight.

[MikeTheCanuck]

Thanks @jimtyhurst. I have seen that same error in other testing but I was unable to reproduce it with the clone of the repo I did just before the PR, so I figured I must have finally flushed it out.

However, I sync'd my fork (mikethecanuck/team-budget) with the main project (hackoregon/team-budget) and tried the docker-compose up --build with that code, and I'm now getting the exact error you are. Very frustrating.

The most informative article I can find referencing that error is this one on StackOverflow, but I can't see how the virtualenv would have any impact inside the container (as you observed):
http://stackoverflow.com/questions/27369314/django-rest-framework-swagger-ui-importerror-no-module-named-rest-framework

[MikeTheCanuck]

OK, I figured it out. This has to do with the /budget_proj/requirements.txt file (which I'd abandoned as did some of you, thinking it was redundant). As with the /Data/folder, Docker can't access /requirements.txt (which at time of writing included the django-rest-swagger reference - as well as psycopyg2), but can only use /budget_proj/requirements.txt.

I'll update these in the PR here later on if someone else doesn't get to it first. (I'm on the road at the moment so I won't have access to a computer for a while - and editing these files on a phone is a mite dangerous.)

[MikeTheCanuck]

Missing dependencies in /budget_proj/requirements.txt have been added back.

Please test again, the Docker container should build and run without a hitch now. Thanks for your patience.

[jimtyhurst]

I tested the Docker build. Looks good.

Questions

(1) Why are we using Python 3.5, rather than the latest 3.6.0?

(2) Each time the image starts, it runs the migrations and imports the data as specified in docker-entrypoint.sh, right? I don't think it should do those things. In general, the application should be configured to access an existing database, so why should we run the migrations and import the data every time the web app starts? This makes me think that the image is accessing sqlite3 locally, rather than querying the PostgreSQL database running on an AWS EC2 instance. Or does the image use whatever database is specified in project_config.py?

Testing procedure

1. git checkout dockerize
2. git pull
3. pip install -r requirements.txt
4. docker-compose up --build
5. Browse to http://localhost:8000/
6. Swagger page appears as expected, served from Docker image.
7. Experimented with other endpoints: /ocrb, /kpm, /ocrb-prod, /kpm-prod, /summary, including using query parameters where allowed. API returned expected results.
8. Stopped the container with Ctrl-C.
9. Restarted the container: docker start budgetproj_web_1
10. Confirmed that endpoints still act the same.
11. Stopped the container: docker stop budgetproj_web_1
12. Started the server locally: ./manage.py runserver
13. Experimented with the endpoints: / (for Swagger), /ocrb, /kpm, /ocrb-prod, /kpm-prod, /summary, including using query parameters where allowed. API returned expected results.
14. Stopped the server with Ctrl-C.

[jimtyhurst]

See my questions in the Conversation tab, but I think this is working well enough to merge.

[MikeTheCanuck]

Great questions @jimtyhurst - I've framed up two of your questions as separate issues ( #50 and #51 ).

As to this question: "This makes me think that the image is accessing sqlite3 locally, rather than querying the PostgreSQL database running on an AWS EC2 instance. Or does the image use whatever database is specified in project_config.py?"

I am pretty confident that the Docker image is using the AWS EC2-hosted PostgreSQL specified in project_config.py. During testing when I'd hit the /summary/ endpoint, my browser would often hang in ways that I hadn't previously seen before we introduced the DATABASE configuration change in settings.py.