This fixes an issue where queries could incorrectly be considered
reusable if a variable was used in two positions: one where it affected
SQL generation and one where it did not.
This mostly simplifies the RootFlds type to make it clearer what it’s
used for, but it has the convenient side-effect of preventing some
“impossible” cases using the type system.
* 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
* 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
* allow ordering using columns from object relationships, close#463
* validate table fields in nested insert
* add tests
* add docs
* change 'table_order_by' type from enums to ordered map
* remove unwanted code from 'Schema.hs' file
* 'AnnGObject' is not list of field name and value tuple
* update docs for new order_by type
* use 'InsOrdHashMap' for 'AnnGObj'
* handle empty fields in order_by
* remove '_' prefixes for asc/desc
* fix the changed order_by syntax across the repo
* support for count and aggregations on columns, close#786
* support explain query for aggregations
* '<arr-rel>_agg' in '<table>' type, fix order by for aggregations
* add 'allow_aggregations' key in select permissions
* Add checkbox to toggle count and aggregations on columns on select permission
* align aggregation checkbox with columns div
* improve readability of the generated sql
* alias is needed at the top level aggregation
* throw internal errors for unexpected fields
* rename SelFld to more readable TableAggFld
* rename agg to aggregate
