Environment variables

Telepresence can import environment variables from the cluster pod when running an intercept. You can then use these variables with the code running on your laptop of the service being intercepted.

There are three options available to do this:

1. telepresence intercept [service] --port [port] --env-file=FILENAME

   This will write the environment variables to a Docker Compose .env file. This file can be used with docker-compose when starting containers locally. Please see the Docker documentation regarding the file syntax and usage for more information.

2. telepresence intercept [service] --port [port] --env-json=FILENAME

   This will write the environment variables to a JSON file. This file can be injected into other build processes.

3. telepresence intercept [service] --port [port] -- [COMMAND]

   This will run a command locally with the pod's environment variables set on your laptop. Once the command quits the intercept is stopped (as if telepresence leave [service] was run). This can be used in conjunction with a local server command, such as python [FILENAME] or node [FILENAME] to run a service locally while using the environment variables that were set on the pod via a ConfigMap or other means.

   Another use would be running a subshell, Bash for example:

   telepresence intercept [service] --port [port] -- /bin/bash

   This would start the intercept then launch the subshell on your laptop with all the same variables set as on the pod.