Cannot find a way to configure environment variables dynamically based on stage

[colesiegel]

I'd like to set up my environment variables based on the current stage.

I initially tried to do this by referencing ${opt:stage} directly in the serverless.ts file, but I found that the value is not evaluated until the file is finished it's execution. As a result, I couldn't use the value of ${opt:stage} to determine my environment variables.

I have also tried to compute the environment variables in a separate serverless.config.js file with a resolver function and import them following the steps here (https://www.serverless.com/framework/docs/providers/aws/guide/variables#exporting-a-function) but the problem is that I cannot set the aws lambda function environment to a variable reference like ${self:custom.config.env} as it expects an environment map of type AwsLambdaEnvironment rather than a string.

Suppose I have a simple requirement - on the local stage there should exist an environment variable called LOCAL_SNS_ENDPOINT set to localhost:1234 and in all other stages this environment variable should not be set. Is there a way to do that with serverless.ts? Due to the previously mentioned issues, I can't seem to dynamically include or exclude environment variables based on the stage.

[colesiegel]

@fredericbarthelet any help much appreciated thank you

[nfritz2016]

I am also experiencing this issue and would like a solution

[colesiegel]

Completely useless feature, worse than a waste of time unless this is addresed

[urg]

I believe the params section can be used to achieve something close (empty env var vs not set).

{
provider: {
  environment: {
     LOCAL_SNS_ENDPOINT: "${param:local_sns_endpoint}"
  }
},
params: {
  local: {
    local_sns_endpoint: 'localhost:1234'
  }
}

[colesiegel]

@urg I don't see how that accomplishes what I asked for.. i.e. setting or leaving environment variable unset based on the stage. Where is the conditional logic in your example? What does putting the value in params accomplish?

[urg]

@colesiegel - see https://www.serverless.com/framework/docs/guides/parameters - the param corresponding to the stage is automatically set.

Admittedly for this example the LOCAL_SNS_ENDPOINT would be empty string instead of not set for any environment other then local, however for many use cases this would be acceptable.

potentially something like the following might work to avoid setting at all (untested)

  environment: {
     (${param:local_sns_endpoint} && ...{LOCAL_SNS_ENDPOINT: "${param:local_sns_endpoint}"})
  }

[arcaela]

@colesiegel You can use dotenv before load configuration, for example:

// serverless.ts
import dotenv from 'dotenv';
dotenv.config()


module.exports = {
 key: process.env.MY_KEY==='myValue' ? 12 : 34
}

sls deploy -c serverless.ts