How to deploy environment variable using serverless deploy for AWS lambda

Question

I am new to AWS lambda i have i am using serveless deploy to deploy my lambda function declared in serverless.yml file. In that file i wrote a lambda function i deployed and it is working fine but problem is that whatever environment variable i gave is not available in console of that lambda function. I might be doing some minor mistake or for deploying environment variable there should be some other syntax. I can go to lambda function in console and add environment variable manually. But my doubt is can we do it while deploying it through serverless deploy

Rahul Rahul · Accepted Answer · 2018-07-06T05:50:29

You can use versions and aliases provided by AWS Lambda

You can create different versions of the same lambda function and give them an alias. Like when you push your lambda code - create a version (say it's 5) - create an alias this (say TEST). When you're sure that its ready for production, create a version(or choose an existing version and name that (say PROD).

Now whenever your lambda function executes, it gives lambda ARN which contains alias, by that you can know which alias(in context.invokedFunctionArn) is executed i.e. that can be used as the environment variable. While invoking the function, you can mention which function to execute from your invocation code.

let thisARN = context.invokedFunctionArn;

// Get the last string in ARN - It's either function name or the alias name
let thisAlias = thisARN.split(":").pop();

Now whenever you deploy a new code, just point the alias to that version. You can use AWS console or CLI for that.

Take a look at this lambda versioning and aliases

For directly deploying to your alias(PROD), you can do this -

    aws lambda update-alias \
    --region region \
    --function-name helloworld \
    --function-version 2 \
    --name PROD

How to deploy environment variable using serverless deploy for AWS lambda

2 Answers