add optional log file to cron job

[kevinschmidt]

Adding an optional logfile parameter that if set will add $logfile to the cron job command using sensible parameters (>> file 2>&1). This also allows no logging or cron email by setting logfile to /dev/null.

[kevinschmidt]

Any changes necessary before it can be merged?

[s0enke]

@kevinschmidt sorry for the late answer, looks like this one got lost across @Jimdo developers.

Could you please add tests which specify the desired behavior? Thanks!

[kevinschmidt]

Sorry for the delay, I added the unit test fir the logfile.

[kevinschmidt]

Hm, not sure why the test is failing, 0 failures reported in the Travis logs.

[s0enke]

@kevinschmidt Maybe the native --log-file option of duplicity might me a better approach? We could also build something more generic like passing additional options to duplicity (e.g. $additional_parameters). This could be used then to pass the --log-file parameter. What do you think?

[kevinschmidt]

@s0enke Sounds good but I have to test that it actually captures all output as one of the major reasons for this change from my point is to switch of logging all together.

[kevinschmidt]

@s0enke I tested it with --log-file /dev/null and duplicity still logs to std out. As far as I understand --log-file is additional logging, not redirect of logging which is the intend here. So I think the code can stay as it or should I make any other changes?