Distinct Environment Variables in Shared Build Configurations Overwritten by Local .travis.yml Entries

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1

Hello,
I’m using a shared build configuration with specific environment variables across multiple pipelines. These variables are different from any that might be defined locally in a pipeline’s .travis.yml file. When there are no environment variables defined in a pipeline’s .travis.yml, the variables from the shared configuration work perfectly. However, when .travis.yml includes its own set of different environment variables, it causes those from the shared configuration to be overwritten. How can we prevent this from happening?

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To manage distinct environment variables in shared build configurations that may be overwritten by local .travis.yml entries, you can leverage several strategies. This ensures that your build configurations are both flexible and robust.

Here’s a detailed guide on how to manage environment variables effectively in Travis CI:

You can define environment variables directly in your .travis.yml file using the env key. These variables can be global or matrix-specific.

env:
  global:
    - GLOBAL_VAR1=value1
    - GLOBAL_VAR2=value2
  matrix:
    - MATRIX_VAR1=value3
    - MATRIX_VAR2=value4

You can set environment variables in the Travis CI web interface. These variables are more secure and can be used to store sensitive information like API keys. They also override any conflicting variables defined in .travis.yml.

  1. Navigate to your repository settings on Travis CI.
  2. Add the required environment variables under the “Environment Variables” section.

Local .travis.yml entries can override environment variables set in shared configurations. To manage this effectively, you can ensure that critical environment variables are not defined locally or use conditional logic to handle different scenarios.

You can use conditional logic within your .travis.yml to set environment variables only if they are not already set.

before_install:
  - export MATRIX_VAR1=${MATRIX_VAR1:-default_value3}
  - export MATRIX_VAR2=${MATRIX_VAR2:-default_value4}

You can se before_script or script.

Another approach is to set or override environment variables within the before_script or script sections of your .travis.yml.

Example:

before_script:
  - export MATRIX_VAR1=${MATRIX_VAR1:-default_value3}
  - export MATRIX_VAR2=${MATRIX_VAR2:-default_value4}

script:
  - echo $MATRIX_VAR1
  - echo $MATRIX_VAR2

By combining these strategies, you can achieve a robust and flexible configuration. For instance, you can define non-sensitive default values in the .travis.yml file and override them with secure values set in the Travis CI web interface.

So you can combine examples as well travis.yml:

env:
  global:
    - GLOBAL_VAR1=value1
    - GLOBAL_VAR2=value2
  matrix:
    - MATRIX_VAR1=default_value3
    - MATRIX_VAR2=default_value4

before_script:
  - export MATRIX_VAR1=${MATRIX_VAR1:-default_value3}
  - export MATRIX_VAR2=${MATRIX_VAR2:-default_value4}

script:
  - echo $GLOBAL_VAR1
  - echo $GLOBAL_VAR2
  - echo $MATRIX_VAR1
  - echo $MATRIX_VAR2

The final way I can think of is adding environment variables MATRIX_VAR1 and MATRIX_VAR2 with the secure value, so thiis setup ensures that:

GLOBAL_VAR1 and GLOBAL_VAR2 are always set to the values defined in the .travis.yml file.

Cheers,
Montana