Environment Variable ​

AirCode supports online setting and modification of environment variables, and they can be accessed through process.env in cloud functions.

Environment variables can be used in the following scenarios:

1. Store key information, such as token, etc., which will not be seen when sharing your code
2. Unified storage and management of configuration information, such as upstream and downstream invoke addresses, for easy modification without changing the code
3. Read system running status through default environment variables
4. More...

Set Environment Variables ​

The environment variable configuration area is located in the Environments tab of the functional area, and can be set directly in the form of key-value pairs.

For example, let's add an environment variable called MY_TEST_ENV with a value of Hello World.

Environment variables can be accessed through process.env in cloud functions. For example, create a cloud function called env.js and modify the code as follows:

module.exports = async function(params, context) {
  // Access environments through `process.env`
  const myEnvValue = process.env.MY_TEST_ENV;
  // `AC_NODE_JS_VERSION` is a system environment represents current runtime's Node.js version
  const nodeVersion = process.env.AC_NODE_JS_VERSION;
  return {
    myEnvValue,
    nodeVersion,
  };
}

module.exports = async function(params, context) {
  // Access environments through `process.env`
  const myEnvValue = process.env.MY_TEST_ENV;
  // `AC_NODE_JS_VERSION` is a system environment represents current runtime's Node.js version
  const nodeVersion = process.env.AC_NODE_JS_VERSION;
  return {
    myEnvValue,
    nodeVersion,
  };
}

Click Debug to see the return result:

{
  "myEnvValue": "Hello World",
  "nodeVersion": "16.17.0"
}

{
  "myEnvValue": "Hello World",
  "nodeVersion": "16.17.0"
}

The number and size of environment variables contain relevant restrictions to ensure the system's stability. Please refer to Resource Limits - Cloud Function - Environment Variables.

Deploy Environment Variables ​

In order to ensure stable online running, all modifications to environment variables will only take effect in the local environment. If you want them to take effect online, you can deploy the function.

For example, after deploying env.js in the above example, access it via curl:

curl https://sample.hk.aircode.run/env

curl https://sample.hk.aircode.run/env

You will get：

{
  "myEnvValue": "Hello World",
  "nodeVersion": "16.17.0"
}

{
  "myEnvValue": "Hello World",
  "nodeVersion": "16.17.0"
}

Indicates that the environment variables are deployed successfully.

System Default Environment Variables ​

In order to make it easier for developers to obtain the runtime status of the system in the code, we provide some system default environment variables, and these variable names start with AC_. E.g:

• AC_NODE_JS_VERSION: Current Node.js runtime version
• AC_REGION: Current App's deployment region

For a complete list of system environment variables, see: Function Runtime - System Environment Variables.