Django and TimescaleDB Test

Test integrating TimescaleDB into Django. It requires a PostgreSQL client and Pipenv to be installed. To start and setup the database.

docker run -d --rm --name timescaledb -p 127.0.0.1:5432:5432 -e POSTGRES_PASSWORD=password timescale/timescaledb:latest-pg12
psql -h 127.0.0.1 -U postgres
--> password
--> CREATE DATABASE sensors;
--> \q
pipenv install
pipenv shell
./manage.py migrate
./manage.py loaddata test_data.json

To start the dev server run ./manage.py runserver

In order to test the smearing of timestamps on collisions, in another terminal, run curl -d "value=<float>" 127.0.0.1:8000/go/ several times while replacing <float> with a number. Then check the resulting timestamps in the terminal output or the admin view. The newely inserted value should always have a timestamp 1 microsecond greater than the last one (timestamp is hard coded into the view).

Troubleshooting

Wrong Python Version

If you only have Python 3.7 installed, change the definition in Pipfile from python_version = "3.8" to python_version = "3.7"

Python manage.py not executing

On Windows run py manage.py to execute the manage.py commands.

Error on migration with compress_segmentby command

If the following error is thrown during a migration, check and update the column name: django.db.utils.ProgrammingError: column "peripheral_component" specified in option timescaledb.compress_segmentby does not exist. Connect to the database server with the above psql command, connect to the database with \c <database_name>, list the tables with \dt and show the table schema of the table to be converterd to a hypertable with \d <table_name>. Sometimes foreign keys have _id appended to their column name. In this example the variables are

• database_name: sensors
• table_name: farms_sensorreading