Antoine Leblanc 4815fcd500 server: progress on generic metadata ... This PR generalizes a bunch of metadata structures. Most importantly, it changes `SourceCache` to hold existentially quantified values: ``` data BackendSourceInfo = forall b. Backend b => BackendSourceInfo (SourceInfo b) type SourceCache = HashMap SourceName BackendSourceInfo ``` This changes a *lot* of things throughout the code. For now, all code using the schema cache explicitly casts sources to Postgres, meaning that if any non-Postgres `SourceInfo` makes it to the cache, it'll be ignored. That means that after this PR is submitted, we can split work between two different aspects: - creating `SourceInfo` for other backends - handling those other sources down the line GitOrigin-RevId: fb9ea00f32e840fc33c5467896fb1dfa5283ab42		2021-01-20 00:32:45 +00:00
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Count.hs	server: progress on generic metadata	2021-01-20 00:32:45 +00:00
Delete.hs	server: progress on generic metadata	2021-01-20 00:32:45 +00:00
Insert.hs	server: progress on generic metadata	2021-01-20 00:32:45 +00:00
Internal.hs	server: support separate metadata database and server code setup for multi sources (#197)	2020-12-28 12:56:55 +00:00
Select.hs	server: progress on generic metadata	2021-01-20 00:32:45 +00:00
Types.hs	server: progress on generic metadata	2021-01-20 00:32:45 +00:00
Update.hs	server: progress on generic metadata	2021-01-20 00:32:45 +00:00