Default or override in variable interpolation

Question

In my build plan I have a a variable injection step which sets a variable (`

bamboo.inject.DOCKER_IMAGE_PATH_MAIN`).  This variable is the path to a docker image generated in the build which will then be used as the execution environment for the subsequent deployment plan.I am able to successfully reference that variable in the deployment spes: DockerConfiguration dockerConfiguration = new DockerConfiguration().image("${bamboo.inject.DOCKER_IMAGE_PATH_MAIN}");

and it is interpolated as expected.  However, if I attempt to deploy a release from a build which does not have this variable injected, the `${bamboo.inject.DOCKER_IMAGE_PATH_MAIN}` string is left as is and docker (understandably) complains it cant find that image.In Bash, I could do something like${bamboo.inject.DOCKER_IMAGE_PATH_MAIN:-bamboo.DOCKER_IMAGE_DEFAULT_PATH}

to fall back to the value of DOCKER_IMAGE_DEFAULT_PATH if DOCKER_IMAGE_PATH_MAIN is not defined.

I was wondering if there is a way to define this sort of logic in bamboo variable interpolation, or alternatively, if there was a way to set a value for an injected variable at deploy time.

Thanks

Marcin Gardias · Answer

You can define a variable with the same name at global, plan or Deployment Environment level.  If injected variable exist it will override, if not, it will resolve to the 'broader scope' variable.

Marcin Gardias · Answer

Actually, deployments do inherit variables from the build that created the release that is being deployed BUT: inject variable task has to be set to create variables in RESULT scope (in other words: not LOCAL)

Eduardo Alvarenga · Answer

Check @Marcin Gardias comment below.