oncall-engine/DEVELOPER.md

• Developer quickstart
  • Code style
  • Backend setup
  • Frontend setup
  • Slack application setup
  • Update drone build
• Troubleshooting
  • ld: library not found for -lssl
  • Could not build wheels for cryptography which use PEP 517 and cannot be installed directly
  • django.db.utils.OperationalError: (1366, "Incorrect string value ...")
  • Empty queryset when filtering against datetime field
• Hints
  • Building the all-in-one docker container
  • Running Grafana with plugin (frontend) folder mounted for dev purposes
  • How to recreate the local database
  • Running tests locally
• IDE Specific Instructions
  • PyCharm

Developer quickstart

Code style

• isort, black and flake8 are used to format backend code
• eslint and stylelint are used to format frontend code
• To run formatters and linters on all files: pre-commit run --all-files
• To install pre-commit hooks: pre-commit install

Backend setup

1. Start stateful services (RabbitMQ, Redis, Grafana with mounted plugin folder)

docker-compose -f docker-compose-developer.yml up -d

NOTE: to use a PostgreSQL db backend, use the docker-compose-developer-pg.yml file instead.

2. postgres is a dependency on some of our Python dependencies (notably psycopg2 (docs)). To install this on Mac you can simply run:

brew install postgresql@14

For non Mac installation please visit here for more information on how to install.

3. Prepare a python environment:

# Create and activate the virtual environment
python3.9 -m venv venv && source venv/bin/activate

# Verify that python has version 3.9.x
python --version

# Make sure you have latest pip and wheel support
pip install -U pip wheel

# Copy and check .env.dev file.
cp .env.dev.example .env.dev

# NOTE: if you want to use the PostgreSQL db backend add DATABASE_TYPE=postgresql to your .env.dev file;
#       currently allowed backend values are `mysql` (default), `postgresql` and `sqlite3`

# Apply .env.dev to current terminal.
# For PyCharm it's better to use https://plugins.jetbrains.com/plugin/7861-envfile/
export $(grep -v '^#' .env.dev | xargs -0)

# Install dependencies.
# Hint: there is a known issue with uwsgi. It's not used in the local dev environment. Feel free to comment it in `engine/requirements.txt`.
cd engine && pip install -r requirements.txt

# Migrate the DB:
python manage.py migrate

# Create user for django admin panel (if you need it):
python manage.py createsuperuser

4. Launch the backend:

# Http server:
python manage.py runserver 0.0.0.0:8080

# Worker for background tasks (run it in the parallel terminal, don't forget to export .env.dev there)
python manage.py start_celery

# Additionally you could launch the worker with periodic tasks launcher (99% you don't need this)
celery -A engine beat -l info

5. All set! Check out internal API endpoints at http://localhost:8000/.

Frontend setup

1. Make sure you have NodeJS v.14+ < 17 and yarn installed. Note: If you are using nvm feel free to simply run cd grafana-plugin && nvm install to install the proper Node version.

2. Install the dependencies with yarn and launch the frontend server (on port 3000 by default)

cd grafana-plugin
yarn install
yarn
yarn watch

3. Ensure /grafana-plugin/provisioning has no grafana-plugin.yml
4. Generate an invitation token:

cd engine;
python manage.py issue_invite_for_the_frontend --override

... or use output of all-in-one docker container described in the README.md.

5. Open Grafana in the browser http://localhost:3000 (login: oncall, password: oncall) notice OnCall Plugin is not enabled, navigate to Configuration->Plugins and click Grafana OnCall

6. Some configuration fields will appear be available. Fill them out and click Initialize OnCall

OnCall API URL:
http://host.docker.internal:8080

Invitation Token (Single use token to connect Grafana instance):
Response from the invite generator command (check above)

Grafana URL (URL OnCall will use to talk to Grafana instance):
http://localhost:3000

NOTE: you may not have host.docker.internal available, in that case you can get the host IP from inside the container by running:

/sbin/ip route|awk '/default/ { print $3 }'

# Alternatively add host.docker.internal as an extra_host for grafana in docker-compose-developer.yml
extra_hosts:
  - "host.docker.internal:host-gateway"

Slack application setup

For Slack app configuration check our docs: https://grafana.com/docs/grafana-cloud/oncall/open-source/#slack-setup

Update drone build

The .drone.yml build file must be signed when changes are made to it. Follow these steps:

If you have not installed drone CLI follow these instructions

To sign the .drone.yml file:

export DRONE_SERVER=https://drone.grafana.net

# Get your drone token from https://drone.grafana.net/account
export DRONE_TOKEN=<Your DRONE_TOKEN>

drone sign --save grafana/oncall .drone.yml

Troubleshooting

ld: library not found for -lssl

Problem:

pip install -r requirements.txt
...
    ld: library not found for -lssl
    clang: error: linker command failed with exit code 1 (use -v to see invocation)
    error: command 'gcc' failed with exit status 1
...

Solution:

export LDFLAGS=-L/usr/local/opt/openssl/lib
pip install -r requirements.txt

Could not build wheels for cryptography which use PEP 517 and cannot be installed directly

Happens on Apple Silicon

Problem:

  build/temp.macosx-12-arm64-3.9/_openssl.c:575:10: fatal error: 'openssl/opensslv.h' file not found
  #include <openssl/opensslv.h>
           ^~~~~~~~~~~~~~~~~~~~
  1 error generated.
  error: command '/usr/bin/clang' failed with exit code 1
  ----------------------------------------
  ERROR: Failed building wheel for cryptography

Solution:

LDFLAGS="-L$(brew --prefix openssl@1.1)/lib" CFLAGS="-I$(brew --prefix openssl@1.1)/include" pip install `cat requirements.txt | grep cryptography`

django.db.utils.OperationalError: (1366, "Incorrect string value ...")

Problem:

django.db.utils.OperationalError: (1366, "Incorrect string value: '\\xF0\\x9F\\x98\\x8A\\xF0\\x9F...' for column 'cached_name' at row 1")

Solution:

Recreate the database with the correct encoding.

Grafana OnCall plugin does not show up in plugin list

Problem: I've run yarn watch in grafana_plugin but I do not see Grafana OnCall in the list of plugins

Solution: If it is the first time you have run yarn watch and it was run after starting Grafana in docker-compose; Grafana will not have detected a plugin to fix: docker-compose -f developer-docker-compose.yml restart grafana

Hints:

Building the all-in-one docker container

cd engine;
docker build -t grafana/oncall-all-in-one -f Dockerfile.all-in-one .

Running Grafana with plugin (frontend) folder mounted for dev purposes

Do it only after you built frontend at least once! Also developer-docker-compose.yml has similar Grafana included.

docker run --rm -it -p 3000:3000 -v "$(pwd)"/grafana-plugin:/var/lib/grafana/plugins/grafana-plugin -e GF_PLUGINS_ALLOW_LOADING_UNSIGNED_PLUGINS=grafana-oncall-app --name=grafana grafana/grafana:8.3.2

Credentials: admin/admin

Running tests locally

In the engine directory, with the .env.dev vars exported and virtualenv activated

pytest

You can also install pytest.xdist in your env and run tests in parallel:

pip install pytest.xdist
pytest -n4

IDE Specific Instructions

PyCharm

1. Create venv and copy .env.dev file

   python3.9 -m venv venv
   cp .env.dev.example .env.dev
   

2. Open the project in PyCharm
3. Settings → Project OnCall
   • In Python Interpreter click the gear and create a new Virtualenv from existing environment selecting the venv created in Step 1.
   • In Project Structure make sure the project root is the content root and add /engine to Sources
4. Under Settings → Languages & Frameworks → Django
   • Enable Django support
   • Set Django project root to /engine
   • Set Settings to settings/dev.py
5. Create a new Django Server run configuration to Run/Debug the engine
   • Use a plugin such as EnvFile to load the .env.dev file
   • Change port from 8000 to 8080