Environments

Overview

You can use variables in input fields and text areas using the ${VARIABLE_NAME} or $VARIABLE_NAME syntax. These variables will be substituted into outgoing requests.

Loading variables

Variables are stored in .env files, and loaded using the --env option.

Here's what a .env file might look like:

# file: dev.env
API_KEY="dev-api-key"
ENV_NAME="dev"
BASE_URL="https://${ENV_NAME}.example.com"

To make these variables available in the UI, you can load them using the --env option:

posting --env dev.env

You can load multiple .env files by specifying the --env option multiple times:

posting --env dev.env --env shared.env

This allows you to build up a set of variables which are common to all environments, and then override them for specific environments.

Using environment variables

By default, Posting will only use variables defined in .env files that have been explicitly loaded using the --env option.

If you want to permit using environment variables that exist on the host machine (i.e. those which are not defined in any .env files), you must set the use_host_environment config option to true (or set the environment variable POSTING_USE_HOST_ENVIRONMENT=true).

Practical example

Imagine you're testing an API which exists in both dev and prod environments.

The dev and prod environments share some common variables, but differ in many ways too. We can model this by having a single shared.env file which contains variables which are shared between environments, and then a dev.env and prod.env file which contain environment specific variables.

# file: shared.env
API_PATH="/api/v1"
ENV_NAME="shared"

# file: dev.env
API_KEY="dev-api-key"
ENV_NAME="dev"
BASE_URL="https://${ENV_NAME}.example.com"

# file: prod.env
API_KEY="prod-api-key"
ENV_NAME="prod"
BASE_URL="https://${ENV_NAME}.example.com"

When working in the dev environment, you can then load all of the shared variables and all of the development environment specific variables using the --env option:

posting --env shared.env --env dev.env

This will load all of the shared variables from shared.env, and then load the variables from dev.env. Since ENV_NAME appears in both files, the value from the dev.env file will be used since that was the last one specified.

Note that you do not need to restart to load changes made to these files, so you can open and edit your env files in an editor of your choice alongside Posting.

Environment specific config

Since all Posting configuration options can also be specified as environment variables, we can also put environment specific config inside .env files. There's a dedicated "Configuration" section in this document which covers this in more detail.

For example, if you wanted to use a light theme in the prod environment (as a subtle reminder that you're in production!), you could set the environment variable POSTING_THEME=solarized-light inside the prod.env file.

Note that configuration files take precedence over environment variables, so if you set a value in both a .env file and a config.yaml, the value from the config.yaml file will be used.