Environment variables in docker

To view variables

1. Log into container

2. printenv

3. printenv PATH

Other options

//in linux
env

//use echo
echo $PATH

To set variables

//to set
export <NAME>='<value>'

//for example to set value for MYPET
export MYPET='cutedog'

//to confirm
printenv MYPET

Set env variable in aws cloudformation

To inject sensitive data into your containers as environment variables, use the secrets container definition parameter.

• Create parameter in AWS parameter store
• Add it in cloudformation template

//code snippet. ExecutionRoleArn is needed because of Secrets and the role needs read permission to access parameter store
TaskDefinition:
    Type: "AWS::ECS::TaskDefinition"
    Properties:
      Family: !Sub "${AWS::StackName}"
      NetworkMode: bridge
      TaskRoleArn: !FindInMap [BuildEnvironment, !Ref 'EnvironmentType', "role"]
      ExecutionRoleArn: !FindInMap [BuildEnvironment, !Ref "EnvironmentType", "executionRole"]
      ContainerDefinitions:
          Secrets:
            - Name: GOOGLE_DRIVE_CREDENTIALS
              ValueFrom: !Sub "arn:aws:ssm:${AWS::Region}:12345678:parameter/GOOGLE_ACCOUNT-${EnvironmentType}"

Use shell script to check environment variables

#check to see if env variable HOME is set
if [[ -n "${HOME}" ]]; then
    echo "$HOME"
else
    echo "Homeless"
fi

Set environment varaibles in Dockerfile

FROM php:8.3.11RC2-zts-alpine3.20

ENV GCT_PROJECT='fluid-fiber-84848484'
ENV GCT_KEY='AIzaSyCejejsllswororowwppw'