* save permissions, relationships and collections in catalog with 'is_system_defined'
* Use common stanzas in the .cabal file
* Refactor migration code into lib instead of exe
* Add new server test suite that exercises migrations
* Make graphql-engine clean succeed even if the schema does not exist
* Separate DB and metadata migrations
* Refactor Migrate.hs to generate list of migrations at compile-time
* Replace ginger with shakespeare to improve performance
* Improve migration log messages
* allow customizing GraphQL root field names, close#981
* document v2 track_table API in reference
* support customising column field names in GraphQL schema
* [docs] add custom column fields doc in API reference
* add tests
* rename 'ColField' to 'ColumnField'
* embed column's graphql field in 'PGColumnInfo'
-> Value constructor of 'PGCol' is not exposed
-> Using 'parseJSON' to construct 'PGCol' in 'FromJSON' instances
* avoid using 'Maybe TableConfig'
* refactors & 'custom_column_fields' -> 'custom_column_names'
* cli-test: add configuration field in metadata export test
* update expected keys in `FromJSON` instance of `TableMeta`
* use `buildSchemaCacheFor` to update configuration in v2 track_table
* remove 'GraphQLName' type and use 'isValidName' exposed from parser lib
* point graphql-parser-hs library git repo to hasura
* support 'set_table_custom_fields' query API & added docs and tests
These changes also add a new type, PGColumnType, between PGColInfo and
PGScalarType, and they process PGRawColumnType values into PGColumnType
values during schema cache generation.
query templates is a little known feature that lets you template rql
queries and serve them as rest apis. This is not relevant anymore
given the GraphQL interface and getting rid of it reduces the dev
time when adding features in few subsystems.
This feature has never been used outside hasura's internal projects or
documented or exposed through console and hence can safely be removed.
* add types to represent unparsed http gql requests
This will help when we add caching of frequently used ASTs
* query plan caching
* move livequery to execute
* add multiplexed module
* session variable can be customised depending on the context
Previously the value was always "current_setting('hasura.user')"
* get rid of typemap requirement in reusable plan
* subscriptions are multiplexed when possible
* use lazytx for introspection to avoid acquiring a pg connection
* refactor to make execute a completely decoupled module
* don't issue a transaction for a query
* don't use current setting for explained sql
* move postgres related types to a different module
* validate variableValues on postgres before multiplexing subs
* don't user current_setting for queries over ws
* plan_cache is only visible when developer flag is enabled
* introduce 'batch size' when multiplexing subscriptions
* bump stackage to 13.16
* fix schema_stitching test case error code
* store hashes instead of actual responses for subscriptions
* internal api to dump subscriptions state
* remove PlanCache from SchemaCacheRef
* allow live query options to be configured on server startup
* capture metrics for multiplexed subscriptions
* more metrics captured for multiplexed subs
* switch to tvar based hashmap for faster snapshotting
* livequery modules do not expose internal details
* fix typo in live query env vars
* switch to hasura's pg-client-hs
1. Haskel library `pg-client-hs` has been updated to expose a function that helps listen to `postgres` notifications over a `channel` in this [PR](https://github.com/hasura/pg-client-hs/pull/5)
2. The server records an event in a table `hdb_catalog.hdb_cache_update_event` whenever any `/v1/query` (that changes metadata) is requested. A trigger notifies a `cache update` event via `hasura_cache_update` channel
3. The server runs two concurrent threads namely `listener` and `processor`. The `listener` thread listens to events on `hasura_cache_update` channel and pushed into a `Queue`. The `processor` thread fetches events from that `Queue` and processes it. Thus server rebuilds schema cache from database and updates.
* remove phase one/two distinction and hdbquery typeclass
* move extensions to default-extensions
* switch to LazyTx which only acquires a connection if needed
* move defns from TH module into Ops module
* remove tojson orphan instance for http exception
* remove orphan instance for dmlp1
* getTopLevelNodes will not throw any exceptions
