Create a sample Python application

This example project provides a Python server-side REST API that interacts with InfluxDB. It is an adaptation of InfluxData IoT Center, simplified to accompany the InfluxData IoT Starter tutorial. You can consume this API with the example iot-api-ui React frontend. The project uses the Flask framework and the InfluxDB API client library for Python.

Features

This application demonstrates how you can use InfluxDB client libraries to do the following:

• Create and manage InfluxDB authorizations (API tokens and permissions).
• Write and query device metadata in InfluxDB.
• Write and query telemetry data in InfluxDB.
• Generate data visualizations with the InfluxDB Giraffe library.

Get started

To learn how to create the app from scratch, follow the IoT Starter tutorial. To run the app, do the following:

1. If you haven't already, create an InfluxDB Cloud account or install InfluxDB OSS.

2. Clone this repository to your machine.

3. Change to the directory--for example, enter the following code into the terminal:

   cd ./iot-api-python

4. Set environment variables for INFLUX_TOKEN and INFLUX_ORG--for example, enter the following commands into your terminal:

   export INFLUX_TOKEN=<INFLUX_TOKEN>
   export INFLUX_ORG=<INFLUX_ORG_ID>

   Replace the following:

   • <INFLUX_TOKEN>: your InfluxDB API token with permission to query (read) buckets and create (write) authorizations for devices.
   • <INFLUX_ORG_ID>: your InfluxDB organization ID.

5. If you need to adjust the defaults to match your InfluxDB instance, edit the settings in./config.ini:

   [APP]
   INFLUX_URL = <INFLUX_URL>
   INFLUX_BUCKET = iot_center
   INFLUX_BUCKET_AUTH = iot_center_devices

   Replace the following:

   • <INFLUX_URL>: your InfluxDB instance URL--for example, the default OSS URL http://localhost:8086.

6. Create and activate a Python virtual environment for the project. Enter the following commands into your terminal:

   # Create a new virtual environment named "virtualenv"
   # Python 3.8+
   python -m venv virtualenv
   
   # Activate the virtualenv (OS X & Linux)
   source virtualenv/bin/activate

7. Install pdm package manager for your system. On Linux or macOS, enter the following command into your terminal:

   curl -sSL https://raw.githubusercontent.com/pdm-project/pdm/main/install-pdm.py | python3 -

   On Windows, enter the following command into your terminal:

   (Invoke-WebRequest -Uri https://raw.githubusercontent.com/pdm-project/pdm/main/install-pdm.py -UseBasicParsing).Content | python -

8. Use pdm to install dependencies. Enter the following command into your terminal:

   pdm install

9. If you use a bash terminal, you can set an environment variable to use dependencies in pdm.lock when you run your application scripts. Enter the following command into your bash terminal:

   eval "$(pdm --pep582)"

10. To start the Flask application, enter the following command into your terminal:

    flask run -h localhost -p 3001

    To view the application, visit http://localhost:3001 in your browser.

11. Next, you can use the example iot-api-ui React frontend to interact with the API.