Stage
: string
in package
Stage denotes one of six possible stages a technology migration could be a part of, progressing through the following order.
OFF -> DUALWRITE -> SHADOW -> LIVE -> RAMPDOWN -> COMPLETE
Cases
OFF
The migration hasn't started. 'old' is authoritative for reads and writes
DUALWRITE
Write to both 'old' and 'new', 'old' is authoritative for reads
SHADOW
Both 'new' and 'old' versions run with a preference for 'old'
LIVE
Both 'new' and 'old' versions run with a preference for 'new'
RAMPDOWN
Only read from 'new', write to 'old' and 'new'
COMPLETE
The migration is finished. 'new' is authoritative for reads and writes