case 4690 - preparing project and organizing

devdocs/old-devdocs/specs/core-log-business.txt

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+Business history log
+
+FROM CASE 79
+A central event log used to track major changes to business objects and major events of significance in AyaNova
+Consumed by various widgets for record history purposes
+Default feature, no need to turn on or off
+Items are only removed from log when source object is deleted (and replaced with a deleted entry and textual description of deleted item)
+Has to handle a scenario where there is no data for an object because in future we will likely have a purge feature or maybe a feature to turn it off and needs to accept that scenario
+?FUTURE: Has some sort of checksum or verification so we can tell it wasn't fucked with (too hard to implement, would be something like a blockchain?)
+?FUTURE: Needs a cleaner job that periodically looks for non-existant objects that are logged
+?FUTURE: keeps logs for 45 days initially keeps forever or until object is deleted
+
+
+ROUTES
+------
+Fetch a constructed, localized log for the following:
+    - Supply user ID, optional time range, get back a log of everything the user did in order for all time or just the specified time range
+    - Supply object type, object id, optional time range, get back a log of history for that object for all time or time range specified
+
+Fetch the above but in raw form as data as well??
+
+EVENT_TYPES
+-----------
+A master enum of all event types in RAVEN.
+Co-used by this log feature, but also used by notification system
+Also used by localized text feature to fetch text about event for display in log and notification etc
+May be used for other things in future.
+Common event types that apply to any object and then specific event types that apply to particular types of objects but all in the same master enum
+
+EventType
+ALL OBJECTS
+1 = created
+2 = retrieved (keep just in case, but perhaps not to be used unless high level of logging required?)
+3 = modified
+4 = deleted
+
+SPECIFIC OBJECT EXAMPLE
+Workorder:
+4=Closed
+5=Servicecompleted
+6=all parts set to used in Service
+7 = accepted from csr
+etc
+
+
+EVENT LOG DB SCHEMA
+------------------------------------
+AYaTYPE (object type int), 
+AYID (object id),
+AYEVENT (event of interest type int defined in central master enum of all events), 
+TIMESTAMP (unix epoch), 
+USERID,
+TEXTRA (text field to identify stuff that can't be retrieved from source object, i.e. deleted record name) 
+
+
+DELETION
+--------
+Initially, the only way an entry is removed from the log is via deletion of the source object
+When a source object is deleted, the entire history for that object is removed from the log and a new entry is created showing the deletion and textual representation of the object
+    - The record has the object type so no need to redundently store that, just the name: "1234" for workorder 1234 or "ABC Accounting" for the client name etc
+
+
+PURGING (FUTURE)
+----------------
+Items that might be most purgeable in any future purge scenario:
+- Retrieved events
+- File attachment download events
+- fetch logfile
+
+
+TODO:
+1) Implement this log and routes to interact with it
+2) Implement a cleaner job to remove events for nonexistant objects that aren't deleted