Source or binary build? ign-tools from binaries, some downstream libraries from source
Description
Expected behavior:
Ignition Tools looks for yaml configuration files in a few different paths:
A path relative to where ign-tools was installed
Paths in the IGN_CONFIG_PATH environment variable
The first supports libraries installed the same way as ign-tools. For example, if ign-tools was installed from debs, then it will find other Ignition libraries also installed from debs. While the latter is convenient when installing libraries to custom locations, for example when installing from source for development.
Currently, the user has to choose one or the other. It would be nice to have a way to easily combine both.
Actual behavior:
If IGN_CONFIG_PATH is set, then the install path is ignored.
Steps to reproduce
Install ignition-tools and libignition-transport<n> from debs
Compile ign-msgs from source
Running ign msgs --help, you'll still be seeing the one from debs
Set export IGN_CONFIG_PATH=path_to_ign-msgs_source_install
Running ign msgs --help, you'll see the one from source, but running ign won't show ign-transport's commands
I suggest that instead of IGN_CONFIG_PATH overriding the default install path, we prepend the install path with paths from the environment variable. This way, the user can override a deb install for one library, like on the example above, but still use all other libraries from debs. The downside is that there's no way to completely prevent debs from being used, but I'm not sure if there's a valid use case for that.
Environment
ign-toolsfrom binaries, some downstream libraries from sourceDescription
Expected behavior:
Ignition Tools looks for yaml configuration files in a few different paths:
ign-toolswas installedIGN_CONFIG_PATHenvironment variableThe first supports libraries installed the same way as
ign-tools. For example, ifign-toolswas installed from debs, then it will find other Ignition libraries also installed from debs. While the latter is convenient when installing libraries to custom locations, for example when installing from source for development.Currently, the user has to choose one or the other. It would be nice to have a way to easily combine both.
Actual behavior:
If
IGN_CONFIG_PATHis set, then the install path is ignored.Steps to reproduce
ignition-toolsandlibignition-transport<n>from debsign-msgsfrom sourceign msgs --help, you'll still be seeing the one from debsexport IGN_CONFIG_PATH=path_to_ign-msgs_source_installign msgs --help, you'll see the one from source, but runningignwon't show ign-transport's commandsAdditional context
Here's where the path logic is:
https://github.com/ignitionrobotics/ign-tools/blob/83d5de7e33da239f714245e53d91b05651601034/src/ign.in#L35-L37
As you can see, if
IGN_CONFIG_PATHis set, it overrides the other.Also note how various Ignition libraries have a disclaimer on their READMEs because of this issue, i.e.
https://github.com/ignitionrobotics/ign-msgs/#known-issue-of-command-line-tools
Suggested solution
I suggest that instead of
IGN_CONFIG_PATHoverriding the default install path, we prepend the install path with paths from the environment variable. This way, the user can override a deb install for one library, like on the example above, but still use all other libraries from debs. The downside is that there's no way to completely prevent debs from being used, but I'm not sure if there's a valid use case for that.