set variable azure pipelines from script code example

Example 1: using variables in azure pipelines

variables:
  global_variable: value    # this is available to all jobs

jobs:
- job: job1
  pool:
    vmImage: 'ubuntu-16.04'
  variables:
    job_variable1: value1    # this is only available in job1
  steps:
  - bash: echo $(global_variable)
  - bash: echo $(job_variable1)
  - bash: echo $JOB_VARIABLE1 # variables are available in the script environment too

- job: job2
  pool:
    vmImage: 'ubuntu-16.04'
  variables:
    job_variable2: value2    # this is only available in job2
  steps:
  - bash: echo $(global_variable)
  - bash: echo $(job_variable2)
  - bash: echo $GLOBAL_VARIABLE

Example 2: using variables in azure pipelines

variables:
 GLOBAL_MYSECRET: $(mySecret) # this will not work because the secret variable needs to be mapped as env
 GLOBAL_MY_MAPPED_ENV_VAR: $(nonSecretVariable) # this works because it's not a secret.

steps:

- powershell: |
    Write-Host "Using an input-macro works: $(mySecret)"
    Write-Host "Using the env var directly does not work: $env:MYSECRET"
    Write-Host "Using a global secret var mapped in the pipeline does not work either: $env:GLOBAL_MYSECRET"
    Write-Host "Using a global non-secret var mapped in the pipeline works: $env:GLOBAL_MY_MAPPED_ENV_VAR" 
    Write-Host "Using the mapped env var for this task works and is recommended: $env:MY_MAPPED_ENV_VAR"
  env:
    MY_MAPPED_ENV_VAR: $(mySecret) # the recommended way to map to an env variable

- bash: |
    echo "Using an input-macro works: $(mySecret)"
    echo "Using the env var directly does not work: $MYSECRET"
    echo "Using a global secret var mapped in the pipeline does not work either: $GLOBAL_MYSECRET"
    echo "Using a global non-secret var mapped in the pipeline works: $GLOBAL_MY_MAPPED_ENV_VAR" 
    echo "Using the mapped env var for this task works and is recommended: $MY_MAPPED_ENV_VAR"
  env:
    MY_MAPPED_ENV_VAR: $(mySecret) # the recommended way to map to an env variable