[Rollouts]Writing Rollouts to persistence

[themiswang]

Base on this summary of events crashlytics record:

Events	API	Persistence File(s)	Will Crash?
non-fatal	recordError()	error_a/b	No
native-fatal	N/A	exception, signal, mach_exception	YES
custom exception	recordExceptionModel()	custom_exception_a/b	No
on-demand fatal	recordOnDemandExceptionModel()	exception(if we consider it's fatal), custom_exception_a/b(if we consider it's non-fatal)	No

Here is how we read rollouts info:

File	SDK log for rollouts	Backend Process
error_a/b (.clsrecord)	each error entry will attach the rollouts state with the entry	read rollouts from each entry
exception, signal, mach_exception (.clsrecord)	write rollouts separately - rollout.clsrecord	read rollouts from rollout.clsrecord
custom_exception (.clsrecord)	for recordExceptionModel() we add rollouts to each exception entry, for on-demand fatal it will read rollouts from rollout.clsrecord	for each entry check if has rollouts attach, if YES then read rollouts info from entry, if NO, read rollouts from rollout.clsrecord

Changes include in this PR:

• write rollouts to rollouts.clsrecord
• write rollouts to error.clsrecord
• write rollouts to custom_exception.clsrecord
• unit tests

#no-changelog

[samedson]

Curious why we're using NSData instead of NSString for this parameter?

[themiswang]

Oh because [NSFileHandle writerData:] need NSData as parameter. The other place for non-fatal I passed as NSString is because the helpers need input as NSString...

[samedson]

Like how you've split out the swift and ObjC parts using a delegate 😎. Just had some questions. Feel free to ping me again when you want another look!

[danasilver]

curious question: is this happening implicitly? I don't see any change to implement it (at least I think)

[themiswang]

Ah if you the the line below, this is actually copy all the file from the one report directory to another. So if the original report contain rollouts then it will be copy to another report directory using the existing logic.

  BOOL copied = [fileManager.underlyingFileManager copyItemAtPath:currentReportPath
                                                           toPath:newReportPath
                                                            error:&error];

[danasilver]

Generally LGTM but definitely deferring to Sam to review this one :)