utah-client postinstall script failure ignored

[Javier Collado]

When installing the utah-client package using gdebi, installation errors aren't detected mainly because gdebi return success (0) even when the underlying installation process failed as in the following example:

(Reading database ... 147223 files and directories currently installed.)
Preparing to replace utah-client 0.4ubuntu46-r634~precise1 (using utah-client_0.4ubuntu46-r634~precise1_all.deb) ...
Unpacking replacement utah-client ...
Setting up utah-client (0.4ubuntu46-r634~precise1) ...
dpkg: error processing utah-client (--install):
 subprocess installed post-installation script returned error exit status 6
Errors were encountered while processing:
 utah-client

To detect this situation on the server side, the output from gdebi should be parsed looking for some string (for example, error exist status) and if that pattern is found, then consider the installation as failed.

[Javier Collado (javier.collado)]

Since the interface in Machine.run states that it returns the output status from the process being call, either that interface has to be updated or the error has to be detected by piping another command. However, with this solution, the real output from the command will be lost and not written to the logs.

[Javier Collado (javier.collado)]

After some testing, I've seen that gdebi fails when a dependency cannot be found (so it's still a useful command), but it doesn't fail when postinstall scripts fails.

In addition to this, the package is considered to be installed so any call to "apt-cache policy" or a script using python-apt library won't be able to detect the failure.

Hence, it seems that the only solution is to take a look at the command output.