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### Overwriting CI variables in the ivas-* repos' CI configs

Usually, everything should be done in the files here, but if there is the need to still overwrite some configuration/control CI variables - e.g. to switch off something temporarily or in a branch-specific manner - this should be done by in a variables: section at the end of the `.gitlab-ci.yml` file.

That way, everything else is included before and the final overwrite of a - possibly existing - variable will be as you want it to be.

Usually, everything should be done in the files here, but if there is the need to still overwrite some configuration/control CI variables - e.g. to switch off something temporarily or in a branch-specific manner - this should be done by in the variables: section at the top of the `.gitlab-ci.yml` file.

Example: The variable `DISABLE_HRTF` is used in ivas-basop to disable all testcase that use external HRTF files.

The relevant part in the `.gitlab-ci.yml` file in ivas-basop looks like given below.

In practice, one would uncomment the last three lines to switch off the HRTF testcase in the respective branch only.

``` yaml

variables:

  # note: GitLab cannot reference variables defined by users in the include ref:, we need to use a YAML anchor for this

  # see https://docs.gitlab.com/ci/yaml/includes/#use-variables-with-include for more information

  IVAS_CODEC_CI_REF: &IVAS_CODEC_CI_REF main

  # If you need to set some config variable only in a local branch, then add an overwrite here

  # One example is DISABLE_HRTF - this will be set on a branch which is about to be merged and will be removed in a subsequent second MR

  # this is more easily done directly here in the child repo

  # these lines are suposed to stay commented out to serve as an example

#variables:

  # # set this to true to skip the external HRTF testcases in pytest calls

#  DISABLE_HRTF: "false"

  # DISABLE_HRTF: "true"

```

Useful configuration variables:

- `DISABLE_HRTF` - adds `-k not model` to `PYTEST_ADDOPTS` which skips the testcases with -hrtf in the selftest. Probably more for historic reasons.

- `BASOP_CI_SCRIPTS_BRANCH` - used to change the branch from which testscripts are pulled, see [here](https://forge.3gpp.org/rep/ivas-codec-pc/ivas-codec/-/wikis/Software-development/Test-Setup-For-BASOP-Code#how-do-i-check-that-my-new-testcase-does-work-for-basop) for more info.

### Some guidelines/hints

- use only one include section at the top of the main yml file to keep things clear, remember that later stuff overwrites earlier stuff