README.md

Project Title

Table of Contents

• About
• Getting Started
• Usage
• Contributing

About

Python WZDx to TIM message translator that is designed to pull messages from the CDOT public WZDx feed and translate to TIM messages.

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes. See deployment for notes on how to deploy the project on a live system.

Prerequisites

This project supports Python >= 3.5. Packages required to run the translator can be installed via pip

pip install -r requirements.txt

Alternatively, if you are running VSCode there is a task available to run this on your behalf. This can be accessed under Task Explorer -> vscode -> pipinstall.

The scripts also require access to the CDOT Postgres database. This can be accessed by setting the environment variables in the .env file. The .env file is not included in the repository for security reasons, however a sample.env file has been provided to show structure required.

In addition to the environment variables for accessing the CDOT Postgres database, the scripts also require the following environment variables to scrape the WZDx endpoint and deposit the resulting TIMs:

1. WZDX_ENDPOINT - the CDOT WZDx URL
2. WZDX_API_KEY - the API key for accessing the WZDx data
3. ODE_ENDPOINT - the ODE URL where translated TIMs will be submitted
4. DURATION_TIME - the duration time in seconds of the TIMs

The WZDx to TIM translator also utilizes a redis cache to reduce the number of times the geospatial endpoint is hit. This cache is currently hosted using the free tier of redis enterprise cloud and does not need to be larger than 30GB. More information on redis enterprise cloud can be found here: https://redis.com/redis-enterprise-cloud/overview/. The following environment variables are necessary to access the redis cache:

1. REDIS_HOST - the hostname of the redis server
2. REDIS_PORT - the redis server port
3. REDIS_PASS - the password used to connect to the redis server

Testing

Unit tests are ran with the python pytest module. To run the tests, run the following command from the root of the project:

python -m pytest ./tests

Again, if you are running VSCode there is a task available to run this on your behalf. This can be accessed under Task Explorer -> vscode -> python test and coverage. This task includes a unit test coverage report to indicate how much of the code is covered by unit tests.

Usage

Note: This project is currently in development and is not yet ready for production use. Limitations are expected.

Running the Translator Locally

Using VSCode, a simple launch.json file has been provided to allow debugging the application. This can be accessed under the Run & Debug tab. The default configuration will run the translator using the functions framework. This runs the translator as a REST service accessed on http://localhost:8080. The translator can be tested by sending a POST request to this endpoint with a WZDx message in the body. The translator will respond with a series of TIM messages in the body of the response.

Running the Translator via Docker

The WZDx/TIM translator can also be run locally using Docker. The translator Dockerfile can be found under Translators/WZDx/ and the redis cache Dockerfile can be found under redis/. Additionally, there is a docker-compose file which builds and runs both the translator and the redis cache. Setting the environment variable RUN_LOCAL to true will run the translator REST service as a flask application that can be accessed on http://localhost:8081. Alternatively, leaving RUN_LOCAL blank will run the translator one time immediately after the build has finished.

Current Known Limitations

• Public GIS endpoint is currently unable to traverse across multiple named routes.
• Translator currently supports only WZDx v4.1 messages
• Only 'CLOSED' ITIS code is supported. Further support is planned
  • "all-lanes-closed" is only supported type at this time