README.md 22 KB

KarmaWorld

Description: A django application for sharing and uploading class notes.

Copyright: FinalsClub, a 501c3 non-profit organization

License: GPLv3 except where otherwise noted

Contact: info@karmanotes.org

v3.0 of the karmanotes.org website from the FinalsClub Foundation

Purpose

KarmaWorld is an online database of college lecture notes. KarmaWorld empowers college students to participate in the free exchange of knowledge.

Naming

The repository and the project are called KarmaWorld. One implementation of KarmaWorld, which is run by FinalsClub Foundation, is called KarmaNotes.

Pre-Installation

Code

Before doing anything, you'll need the code. Grab it from github.

Clone the project from the central repo using your github account:

git clone git@github.com:FinalsClub/karmaworld.git

If you aren't using a system setup for github, then grab the project with this command instead:

git clone https://github.com/FinalsClub/karmaworld.git

Generally speaking, this will create a subdirectory called karmaworld under the directory where the git command was run. This git repository directory will be referred to herein as {project_root}.

There might be some confusion as the git repository's directory will likely be called karmaworld (this is {project_root}), but there is also a karmaworld directory underneath that ({project_root}/karmaworld) alongside files like fabfile.py ({project_root}/fabfile.py) and README.md ({project_root}/README.md).

External Software Dependencies

pdf2htmlEX

KarmaWorld uses pdf2htmlEX as a dependency. pdf2htmlEX is used to convert uploaded PDF notes into HTML.

An outdated version of pdf2htmlEX is available which includes the patch required for pdf2htmlEX to correctly work with KarmaWorld.

Newer versions can be used by applying the patch by hand. It's a fairly simple two-line modification that can be done after installing pdf2htmlEX.

SSL Certificate

If you wish to host your system publicly, you'll almost certainly want an SSL certificate signed by a proper authority.

You may need to set the SSL_REDIRECT environment variable to true to make KarmaWorld redirect insecure connections to secure ones.

Follow Heroku's SSL setup to get SSL running on your server with Heroku.

External Service Dependencies

Notice: A number of services are required even if running the KarmaWorld web service locally. Some of the services are recommended, and some are completely optional even if running the web service on Heroku.

This software makes use of external third party services which require accounts to access the service APIs. Without these third parties available, this software may require considerable overhaul. These services have API keys, credentials, and other information that you must provide to KarmaWorld as environment variables.

The best way to persist these API keys in environment variables is by using a .env file. Copy .env.example to .env and populate the fields as required.

Many of these services have free tiers and can be used without charge for development testing purposes.

  • Reminder
    • Copy .env.example to .env and populate the environment variables there.
  • Required Services
  • Optional but recommended
    • IndexDen: enables searching through courses, notes, etc
    • Heroku: the production environment used by karmanotes.org
    • it might not be possible to run KarmaWorld on Heroku using a free webapp.
    • Amazon S3: for static file hosting
  • Entirely optional (though used in the production environment)

Heroku

This project has chosen to use Heroku to host the Django and celery software. While not a hard requirement, the more up-to-date parts of this documentation will operate assuming Heroku is in use.

See README.heroku for more information.

pdf2htmlEX on Heroku

If using Heroku, the default KarmaNotes Heroku buildpack will include the required version of pdf2htmlEX.

Celery Queue

Celery uses the Apache Message Queueing Protocol for passing messages to its workers.

For production, we recommend using Heroku's CloudAMQP add-on, getting your own CloudAMQP account, or running a queueing system on your own. The CLOUDAMQP_URL environment variable must be set correctly for KarmaWorld to be able to use Celery. The CELERY_QUEUE_NAME environment variable must be set to the name of the queue you wish to use. Settings this to something unique allows multiple instances of KarmaWorld (or some other software) to share the same queueing server.

For development on localhost, RabbitMQ is the default for djcelery and is well supported. Ensure RabbitMQ is installed for local development.

PostgreSQL

PostgreSQL is not necessarily required; other RDBMS could probably be fit into place. However, the code was largely written assuming PostgreSQL will be used. Change to another system with the caveat that it might take some work.

There are many cloud providers which provide PostgreSQL databases. Heroku has an add-on for providing a PostgreSQL database. Ensure something like this is made available and installed to the app.

For local development, ensure a PostgreSQL is running on localhost or is otherwise accessible.

Amazon S3

The instructions for creating an S3 bucket may be found on Amazon.

Two, separate buckets may be used in production: one for static file hosting and one as a communication bus with Filepicker.

S3 for Filepicker

This software uses S3 to store files which are sent to or received from Filepicker. Filepicker will need to know the S3 bucket name, access key, and secret key.

Filepicker users can only make use of an S3 bucket with a paid account. For development purposes, no Filepicker S3 bucket is needed. Skip all references to the Filepicker S3 bucket in the development case.

The software will not need to know the S3 credentials for the Filepicker bucket, because the software will upload files to the Filepicker S3 bucket through Filepicker's API and it will link to or download files from the Filepicker S3 bucket through Filepicker's URLs. This will be covered in the Filepicker section.

S3 for static files

This software uses S3 for hosting static files. The software will need to update static files on the S3 bucket. As such, the software will need the S3 bucket name, access key, and secret key via the environment variables. This is described in subsections below.

To support static hosting, DEFAULT_FILE_STORAGE should be set to 'storages.backends.s3boto.S3BotoStorage', unless there is a compelling reason to change it.

There are three ways to setup access to the S3 buckets depending upon speed and security. The more secure, the slower it will be to setup.

insecure S3 access

For quick and dirty insecure S3 access, create a single group and a single user with full access to all buckets. Full access to all buckets is insecure!

Create an Amazon IAM group with full access to the S3 bucket. Select the "Amazon S3 Full Accesss" Policy Template.

Create an Amazon IAM user. Copy the credentials into the AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables. Be sure to write down the access information, as it will only be shown once.

secure S3 access

For secure S3 access, two users will be needed. One with access to the Filepicker bucket and one with access to the static hosting bucket.

Note: this might need to be modified to prevent creation and deletion of buckets?

Create an Amazon IAM group with full access to the S3 bucket. The quick way is to select the "Amazon S3 Full Accesss" Policy Template and replace "Resource": "*" with "Resource": "arn:aws:s3:::<static_bucket_name>".

Create an Amazon IAM user. Copy the credentials into the AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables. Be sure to write down the access information, as it will only be shown once.

Ensure the created user is a member of the group with access to the S3 static files bucket.

Repeat the process again, creating a group for the Filepicker bucket and creating a user with access to that group. These credentials will be passed on to Filepicker.

somewhat secure S3 access

Create two groups as described in the secure S3 access section above.

Create a single user, save the credentials as described in the insecure S3 access section above, and pass the credentials on to Filepicker.

Add the single user to both groups.

This is less secure because if your web server or Filepicker get compromised (so there are two points for potential failure), the single compromised user has full access to both buckets.

Amazon Cloudfront CDN

Cloudfront CDN assists static file hosting.

Follow Amazon's instructions to host static files out of the appropriate S3 bucket. Note that Django's static file upload process has been modified to mark static files as publicly assessible.

In the settings for the Cloudfront Distribution, copy the "Domain Name" from General settings and set CLOUDFRONT_DOMAIN to it. For example, abcdefghij.cloudfront.net.

Amazon Mechanical Turk

Mechanical turk is employed to generate human feedback from uploaded notes. This service is helpful for generating flash cards and quizzes.

This service is optional and it might cause unexpected charges when deployed. If the required environment variable is not found, then no errors will occur and no mechanical turk tasks will be created, avoiding any unexpected costs.

The MTURK_HOST environment variable is almost certainly "mechanicalturk.amazonaws.com".

The code will create and publish HITs on your behalf.

Google Drive

This software uses Google Drive to convert documents to and from various file formats.

A Google Drive service account with access to the Google Drive is required. This may be done with a Google Apps account with administrative privileges, or ask your business sysadmin.

Follow Google's instructions to create a Google Drive service account. If using Google Apps, it is worth looking at these instructions.

Populate the GOOGLE_USER environment variable with the email address of the user whose Google Drive will be accessed. This is typically your own email address.

Google Drive used to use p12 files by default. Now a new-style JSON file is downloaded by default when creating new credentials. Until the code has been updated to use the new-style JSON file, make sure to click the Generate a new P12 key button.

While on the Credentials page (with the Generate a new P12 key button visible), note the Service account Email address. It will have a format like numbers-alphanumerics@developer.gserviceaccount.com. Copy this value and paste it into the GOOGLE_SERVICE_EMAIL environment variable.

Convert the p12 file into a Base64 encoded string for the GOOGLE_SERVICE_KEY_BASE64 environment variable. There are many ways to do this. If Python is available, the binascii library makes this very easy:

    import binascii
    with open('file.p12', 'r') as f:
        print binascii.b2a_base64(f.read)

Filepicker

This software uses Filepicker for uploading files. This requires an account with Filepicker.

Filepicker can use an additional third party file hosting site where it may send uploaded files. This project, in production, uses Amazon S3 as the third party. See the Amazon S3 section above for more information.

In development, an S3 bucket will not be necessary. The Free Plan should suffice.

Create a new App with Web SDK and provide the Heroku App URL for the Application's URL. You'll be given an API Key for the App. Paste this into the FILEPICKER_API_KEY environment variable.

Find the 'App Security' button on the left hand side of the web site. Make sure 'Use Security' is enabled. Generate a new app secret. It might require reloading the page to see the new secret. Paste this secret into the FILEPICKER_SECRET environment variable.

If you have an upgraded plan, you can configure Filepicker to have access to your Filepicker S3 bucket. Click 'Amazon S3' on the left hand side menu and supply the credentials for the user with access to the Filepicker S3 bucket.

IndexDen

KarmaWorld uses IndexDen to create a searchable index of all the notes in the system. Create an free IndexDen account at their homepage. You will be given a private URL that accesses your IndexDen account. This URL is visible on your dashboard (you might need to scroll down).

Set the INDEXDEN_PRIVATE_URL environment variable to your private URL.

Set the INDEXDEN_INDEX environment variable to the name of the index you want to use for KarmaWorld. The index will be created automatically when KarmaNotes is run if it doesn't already exist. It may be created through the GUI if desired.

Twitter

Twitter is used to post updates about new courses. Access to the Twitter API will be required for this task.

If this Twitter feature is desired, the consumer key and secret as well as the access token key and secret are needed by the software.

If the required environment variables are not found, then no errors will occur and no tweets will be posted.

To set this up, create a new Twitter application. Use your Heroku App URL for the website field. Leave the Callback field blank.

Make sure this application has read/write access. Generate an access token. Go to your OAuth settings, and grab the "Consumer key", "Consumer secret", "Access token", and "Access token secret". Paste these, respectively, into the environment variables TWITTER_CONSUMER_KEY, TWITTER_CONSUMER_SECRET, TWITTER_ACCESS_TOKEN_KEY, TWITTER_ACCESS_TOKEN_SECRET.

Local

Configuring foreman

KarmaNotes runs on Heroku as a webapp and thus makes use of a Procfile. While not strictly necessary, KarmaWorld can use the same basic Procfile which is convenient and consistent.

To use the Procfile locally, we recommend using foreman. To install foreman and other Heroku tools, install the Heroku toolbelt.

Ensure environment variables are available to foreman by copying .env.example to .env and update those variables as appropriate for your local system.

pdf2htmlEX

This project uses pdf2htmlEX as a dependency. pdf2htmlEX is used to convert uploaded PDF notes into HTML. It needs to be installed on the same system that KarmaWorld is running on.

using their source

See their instructions at https://github.com/coolwanglu/pdf2htmlEX/wiki/Building.

Make sure to patch the source code to expose two variables.

using our fork

You can use FinalsClub's outdated version of pdf2htmlEX. See their installation instructions above, but don't worry about patching.

using their PPA

You can use their upstream PPA.

    apt-add-repository ppa:coolwanglu/pdf2htmlex
    apt-get update
    apt-get install pdf2htmlex

Then patch the javascript on your system by running this code in the shell.

    cat >> `dpkg -L pdf2htmlex | grep pdf2htmlEX.js` <<PDF2HTMLEXHACK
    Viewer.prototype['rescale'] = Viewer.prototype.rescale;
    Viewer.prototype['scroll_to'] = Viewer.prototype.scroll_to;
    PDF2HTMLEXHACK

Install

  1. virtualenv venv
  2. source venv/bin/activate
  3. pip install -r requirements.txt
    • on Debian systems, some packages are required for pip to succeed:
    • apt-get install python-dev libpython-dev python-psycopg2 libmemcached-dev libffi-dev libssl-dev postgresql-server-dev-X.Ylibxml2-dev libxslt-dev
  4. pip install -r requirements-dev.txt

Configuration

Make sure External Service Dependencies are satisfied. This includes running a local database and RabbitMQ instance as desired.

  1. configure .env as per instructions
  2. foreman run python manage.py syncdb --migrate --noinput
  3. foreman run python manage.py createsuperuser
  4. foreman run python manage.py fetch_usde_csv ./schools.csv
  5. foreman run python manage.py import_usde_csv ./schools.csv
  6. foreman run python manage.py sanitize_usde_schools
  • fetch_usde_csv downloads school records and stores them to ./schools.csv. This file name and location is arbitrary. As long as the same file is passed into import_usde_csv for reading, everything should be fine.

  • fetching_usde_csv requires 7zip to be installed for processing compressed archives. On Debian-based systems, this entails apt-get install p7zip-full

If using DJANGO_SETTINGS_MODULE='karmaworld.settings.dev' in .env, static file hosting should be done by local files. DEFAULT_FILE_STORAGE should be set to django.core.files.storage.FileSystemStorage.

If using DJANGO_SETTINGS_MODULE='karmaworld.settings.prod' in .env, static file hosting is done by DEFAULT_FILE_STORAGE defined in .env.

Run

Make sure you are inside your virtual environment (source venv/bin/activate).

Static file hosting makes use of compression if using DJANGO_SETTINGS_MODULE='karmaworld.settings.prod'. If using compression and the code has changed or this is the first run, make sure any modified static files get compressed with foreman run python manage.py compress. Static files then need to be uploaded correctly with foreman run python manage.py collectstatic.

Run foreman start. foreman will load the .env file and manage running all processes in a way that is similar to that of Heroku. This allows better consistency with local, staging, and production deployments.

To run web-only, but no celery or beat, run foreman start web to specify strictly the web worker.

Press ctrl-C to kill foreman. Foreman will run Django's runserver command. If you wish to have more control over how this is done, you can do foreman run python manage.py runserver <options>. For running any other manage.py commands, you should also precede them with foreman run like just shown. This simply ensures that the environment variables from .env are present.

Heroku Install

KarmaNotes runs on Heroku as a webapp. This section addresses what was done for KarmaNotes so that other implementations of KarmaWorld can be run on Heroku.

Before anything else, download the Heroku toolbelt.

To run KarmaWorld on Heroku, do heroku create and git push heroku master as typical for a Heroku application. Set your the variable BUILDPACK_URL to https://github.com/FinalsClub/heroku-buildpack-karmanotes to use a buildpack designed to support KarmaNotes.

You will need to import the US Department of Education's list of accredited schools.

  1. Fetch USDE schools with heroku run python manage.py fetch_usde_csv ./schools.csv
  2. Upload the schools into the database with heroku run python /manage.py import_usde_csv ./schools.csv
  3. Clean up redundant information with heroku run python /manage.py sanitize_usde_schools

Django Database management

South

We have setup Django to use south for migrations. When changing models, it is important to run foreman run python manage.py schemamigration which will create a migration to reflect the model changes into the database. These changes can be pulled into the database with foreman run python manage.py migrate.

Sometimes the database already has a migration performed on it, but that information wasn't told to south. There are subtleties to the process which require looking at the south docs. As a tip, start by looking at the --fake flag.

Assets from Third Parties

A number of assets have been added to the repository which come from external sources. It would be difficult to keep a complete list in this README and keep it up to date. Software which originally came from outside parties can generally be found in karmaworld/assets.

Additionally, all third party Python projects (downloaded and installed with pip) are listed in these files:

  • requirements.txt
  • requirements-dev.txt

Thanks

  • KarmaNotes.org is a project of the FinalsClub Foundation with generous funding from the William and Flora Hewlett Foundation

  • Also thanks to rdegges for the django-skel template