activate

A tool to manage environment-specific configurations. Simplifying working across various settings like Development, Testing, Production, etc.

Motivation

Problem Statement

Code in different environments such as Dev, QA, Prod, etc. may need various configurations to run. The solution often used is loading environment variables or property files at build or run time. This by itself has a few drawbacks:

• Setting up environments may take some additional imperative configuration, or worse, manual developer setup.
• Switching between environments is tedious.
• Developers may have to maintain custom implementations and build scripts.
• No good solution exists for switching entire monorepos between environments. Instead, a master config is often used.

Solution

activate solves all these problems.

• An active.toml file declaratively defines environments.
• Loading and unloading an environment is as easy as a single command.
• No custom build scripts necessary. Each environment has managed files/directories and environment variables.
• The config can be distributed throughout a repo and everything switched with a single command.

More Details

Files and Directories

Different environments like Dev, QA, etc. may have assets, data files, executables, or program files that should be used in each. All of these can be switched over at once. e.g.

[dev.links]
"app/data" = "path/to/dev/data"

[qa.links]
"app/data" = "path/to/qa/data"

The result of the above is app/data is created and symlinked to the file or directory of the active environment.

Env Variables

Often each environment has specific environment variables. This can be easily defined. e.g.

[dev.env]
HOST = "localhost"
PORT = 3000

[qa.env]
HOST = "178.32.44.2"
PORT = 443

To load an environment into your current shell, and unload any activate environment, run

eval "$(activate <name>)"`

Consider adding the following to ~/.bashrc as a shortcut

a() {
    eval "$(activate "$@")";
}

Then you can easily load and unload environments with an even shorter command

a dev

Monorepo

activate.toml files can be distributed across a codebase, where each application has its own activate.toml file. From the root of the repo everything can be switched together with the -d flag. e.g.

activate -d <name>

Any directory/subdirectory (respecting .gitignore) with an activate.toml file is switched to <name>.

activate.toml Schema

[<ENV_NAME>.env]
<ENV_VAR_NAME> = <ENV_VAR_VALUE>

[<ENV_NAME>.links]
"<LINK_PATH_FROM_ROOT>" = "<SOURCE_PATH_FROM_ROOT>"

Install

cargo install activate