[webservice] No longer recorrect files when output files seem to still be around

Description

ITDM would like to remove AGIPD proc data from older proposals which we consider as reproducible, but such runs are unfortunately accompanied by other detectors without this guarantee.

Since the recorrect webservice action via myMdC is anyway meant to be used for deleted data and not so much restoring prior, arbitrary versions, this MR changes the webservice to check for the existance of the first sequence file of the first aggregator, and skip recorrection if it exists.

How Has This Been Tested?

TBD

Types of changes

• Bug fix (non-breaking change which fixes an issue)

Reviewers

@kluyvert

webservice/messages.py

@@ -5,6 +5,7 @@ class Errors:
     UNKNOWN_ACTION = "FAILED: action {} is not known!, please contact det-support@xfel.eu"
     PATH_NOT_FOUND = "FAILED: run at {} not found!, please contact det-support@xfel.eu"
     NOTHING_TO_DO = "WARN: nothing to calibrate in path {}, please contact det-support@xfel.eu"
+    NOTHING_TO_REDO = "WARN: nothing to re-calibrate in path {}, please contact det-support@xfel.eu"
     CONFIG_ERROR = "FAILED: configuration at {} couldn't be parsed, using default!, please contact det-support@xfel.eu"
     CONFIG_NOT_FOUND = "WARN: configuration at {} not found, using default!, please contact det-support@xfel.eu"
     NO_DEFAULT_CONFIG = "FAILED: No default config for instrument {}, detector {} exists!, please contact det-support@xfel.eu"