Query plan caching was introduced by - I believe - hasura/graphql-engine#1934 in order to reduce the query response latency. During the development of PDV in hasura/graphql-engine#4111, it was found out that the new architecture (for which query plan caching wasn't implemented) performed comparably to the pre-PDV architecture with caching. Hence, it was decided to leave query plan caching until some day in the future when it was deemed necessary.
Well, we're in the future now, and there still isn't a convincing argument for query plan caching. So the time has come to remove some references to query plan caching from the codebase. For the most part, any code being removed would probably not be very well suited to the post-PDV architecture of query execution, so arguably not much is lost.
Apart from simplifying the code, this PR will contribute towards making the GraphQL schema generation more modular, testable, and easier to profile. I'd like to eventually work towards a situation in which it's easy to generate a GraphQL schema parser *in isolation*, without being connected to a database, and then parse a GraphQL query *in isolation*, without even listening any HTTP port. It is important that both of these operations can be examined in detail, and in isolation, since they are two major performance bottlenecks, as well as phases where many important upcoming features hook into.
Implementation
The following have been removed:
- The entirety of `server/src-lib/Hasura/GraphQL/Execute/Plan.hs`
- The core phases of query parsing and execution no longer have any references to query plan caching. Note that this is not to be confused with query *response* caching, which is not affected by this PR. This includes removal of the types:
- - `Opaque`, which is replaced by a tuple. Note that the old implementation was broken and did not adequately hide the constructors.
- - `QueryReusability` (and the `markNotReusable` method). Notably, the implementation of the `ParseT` monad now consists of two, rather than three, monad transformers.
- Cache-related tests (in `server/src-test/Hasura/CacheBoundedSpec.hs`) have been removed .
- References to query plan caching in the documentation.
- The `planCacheOptions` in the `TenantConfig` type class was removed. However, during parsing, unrecognized fields in the YAML config get ignored, so this does not cause a breaking change. (Confirmed manually, as well as in consultation with @sordina.)
- The metrics no longer send cache hit/miss messages.
There are a few places in which one can still find references to query plan caching:
- We still accept the `--query-plan-cache-size` command-line option for backwards compatibility. The `HASURA_QUERY_PLAN_CACHE_SIZE` environment variable is not read.
https://github.com/hasura/graphql-engine-mono/pull/1815
GitOrigin-RevId: 17d92b254ec093c62a7dfeec478658ede0813eb7
## Description
Thanks to #1664, the Metadata API types no longer require a `ToJSON` instance. This PR follows up with a cleanup of the types of the arguments to the metadata API:
- whenever possible, it moves those argument types to where they're used (RQL.DDL.*)
- it removes all unrequired instances (mostly `ToJSON`)
This PR does not attempt to do it for _all_ such argument types. For some of the metadata operations, the type used to describe the argument to the API and used to represent the value in the metadata are one and the same (like for `CreateEndpoint`). Sometimes, the two types are intertwined in complex ways (`RemoteRelationship` and `RemoteRelationshipDef`). In the spirit of only doing uncontroversial cleaning work, this PR only moves types that are not used outside of RQL.DDL.
Furthermore, this is a small step towards separating the different types all jumbled together in RQL.Types.
## Notes
This PR also improves several `FromJSON` instances to make use of `withObject`, and to use a human readable string instead of a type name in error messages whenever possible. For instance:
- before: `expected Object for Object, but encountered X`
after: `expected Object for add computed field, but encountered X`
- before: `Expecting an object for update query`
after: `expected Object for update query, but encountered X`
This PR also renames `CreateFunctionPermission` to `FunctionPermissionArgument`, to remove the quite surprising `type DropFunctionPermission = CreateFunctionPermission`.
This PR also deletes some dead code, mostly in RQL.DML.
This PR also moves a PG-specific source resolving function from DDL.Schema.Source to the only place where it is used: App.hs.
https://github.com/hasura/graphql-engine-mono/pull/1844
GitOrigin-RevId: a594521194bb7fe6a111b02a9e099896f9fed59c
- Add export list to Hasura.Eventing.Common
- Group logging options in one type / argument
- Group request header processing code in one place
This doesn't address the convoluted logic, but should make it a bit easier
to figure out what's going on for the next person.
https://github.com/hasura/graphql-engine-mono/pull/1710
GitOrigin-RevId: 34b0abdd1b86b5836eb512484acb0db8c81f3014
Removing `schemaSyncDisable` flag and interpreting `schemaPollInterval` of `0` as disabling schema sync.
This change brings the convention in line with how action and other intervals are used to disable processes.
There is an opportunity to abstract the notion of an optional interval similar to how actions uses `AsyncActionsFetchInterval`.
This can be used for the following fields of ServeOptions, with RawServeOptions having a milliseconds value where `0` is interpreted as disable.
OptionalInterval:
```
-- | Sleep time interval for activities
data OptionalInterval
= Skip -- ^ No polling
| Interval !Milliseconds -- ^ Interval time
deriving (Show, Eq)
```
ServeOptions:
```
data ServeOptions impl
= ServeOptions
{
...
, soEventsFetchInterval :: !OptionalInterval
, soAsyncActionsFetchInterval :: !OptionalInterval
, soSchemaPollInterval :: !OptionalInterval
...
}
```
Rather than encoding a `Maybe OptionalInterval` in RawServeOptions, instead a `Maybe Milliseconds` can be used to more directly express the input format, with the ServeOptions constructor interpreting `0` as `Skip`.
Current inconsistencies:
* `soEventsFetchInterval` has no value interpreted as disabling the fetches
* `soAsyncActionsFetchInterval` uses an `OptionalInterval` analog in `RawServeOptions` instead of `Milliseconds`
* `soSchemaPollInterval` currently uses `Milliseconds` directly in `ServeOptions`
---
### Kodiak commit message
Information used by [Kodiak bot](https://kodiakhq.com/) while merging this PR.
#### Commit title
Same as the title of this pull request
GitOrigin-RevId: 3cda1656ae39ae95ba142512ed4e123d6ffeb7fe
Modifying schema-sync implementation to use polling for OSS/Pro. Invalidations are now propagated via the `hdb_catalog.hdb_schema_notifications` table in OSS/Pro. Pattern followed is now a Listener/Processor split with Cloud listening for changes via a LISTEN/NOTIFY channel and OSS polling for resource version changes in the metadata table. See issue #460 for more details.
GitOrigin-RevId: 48434426df02e006f4ec328c0d5cd5b30183db25
Multi source support had limited the availability of async action queries in subscriptions. This PR
adds support for async action query subscriptions with new implementation. Also addresses https://github.com/hasura/graphql-engine/issues/6460.
GitOrigin-RevId: 5ddc321073d224f287dc4b86ce2239ff55190b36
* add `use_prepared_statements` option to add_pg_source API
* update CHANGELOG.md
* change default value for 'use_prepared_statements' to False
* update CHANGELOG.md
GitOrigin-RevId: 6f5b90991f4a8c03a51e5829d2650771bb0e29c1
While debugging issues with HLS, Reed Mullanix noticed that we don't use relative paths. This leads to problems when using HLS + Emacs due to a bug in `lsp-mode` which prevents it from finding the correct project root.
However, it is still a good practice to use relative paths in TH for other reasons, including being able to import these modules in GHCI.
This PR should make it so HLS-1.0 & emacs provide type inference, imports, etc., in all modules in our codebase.
GitOrigin-RevId: 5f53b9a7ccf46df1ea7be94ff0a5c6ec861f4ead
fixes#3868
docker image - `hasura/graphql-engine:inherited-roles-preview-48b73a2de`
Note:
To be able to use the inherited roles feature, the graphql-engine should be started with the env variable `HASURA_GRAPHQL_EXPERIMENTAL_FEATURES` set to `inherited_roles`.
Introduction
------------
This PR implements the idea of multiple roles as presented in this [paper](https://www.microsoft.com/en-us/research/wp-content/uploads/2016/02/FGALanguageICDE07.pdf). The multiple roles feature in this PR can be used via inherited roles. An inherited role is a role which can be created by combining multiple singular roles. For example, if there are two roles `author` and `editor` configured in the graphql-engine, then we can create a inherited role with the name of `combined_author_editor` role which will combine the select permissions of the `author` and `editor` roles and then make GraphQL queries using the `combined_author_editor`.
How are select permissions of different roles are combined?
------------------------------------------------------------
A select permission includes 5 things:
1. Columns accessible to the role
2. Row selection filter
3. Limit
4. Allow aggregation
5. Scalar computed fields accessible to the role
Suppose there are two roles, `role1` gives access to the `address` column with row filter `P1` and `role2` gives access to both the `address` and the `phone` column with row filter `P2` and we create a new role `combined_roles` which combines `role1` and `role2`.
Let's say the following GraphQL query is queried with the `combined_roles` role.
```graphql
query {
employees {
address
phone
}
}
```
This will translate to the following SQL query:
```sql
select
(case when (P1 or P2) then address else null end) as address,
(case when P2 then phone else null end) as phone
from employee
where (P1 or P2)
```
The other parameters of the select permission will be combined in the following manner:
1. Limit - Minimum of the limits will be the limit of the inherited role
2. Allow aggregations - If any of the role allows aggregation, then the inherited role will allow aggregation
3. Scalar computed fields - same as table column fields, as in the above example
APIs for inherited roles:
----------------------
1. `add_inherited_role`
`add_inherited_role` is the [metadata API](https://hasura.io/docs/1.0/graphql/core/api-reference/index.html#schema-metadata-api) to create a new inherited role. It accepts two arguments
`role_name`: the name of the inherited role to be added (String)
`role_set`: list of roles that need to be combined (Array of Strings)
Example:
```json
{
"type": "add_inherited_role",
"args": {
"role_name":"combined_user",
"role_set":[
"user",
"user1"
]
}
}
```
After adding the inherited role, the inherited role can be used like single roles like earlier
Note:
An inherited role can only be created with non-inherited/singular roles.
2. `drop_inherited_role`
The `drop_inherited_role` API accepts the name of the inherited role and drops it from the metadata. It accepts a single argument:
`role_name`: name of the inherited role to be dropped
Example:
```json
{
"type": "drop_inherited_role",
"args": {
"role_name":"combined_user"
}
}
```
Metadata
---------
The derived roles metadata will be included under the `experimental_features` key while exporting the metadata.
```json
{
"experimental_features": {
"derived_roles": [
{
"role_name": "manager_is_employee_too",
"role_set": [
"employee",
"manager"
]
}
]
}
}
```
Scope
------
Only postgres queries and subscriptions are supported in this PR.
Important points:
-----------------
1. All columns exposed to an inherited role will be marked as `nullable`, this is done so that cell value nullification can be done.
TODOs
-------
- [ ] Tests
- [ ] Test a GraphQL query running with a inherited role without enabling inherited roles in experimental features
- [] Tests for aggregate queries, limit, computed fields, functions, subscriptions (?)
- [ ] Introspection test with a inherited role (nullability changes in a inherited role)
- [ ] Docs
- [ ] Changelog
Co-authored-by: Vamshi Surabhi <6562944+0x777@users.noreply.github.com>
GitOrigin-RevId: 3b8ee1e11f5ceca80fe294f8c074d42fbccfec63
- [x] **Event Triggers Metrics**
- [x] Distribution of size of event trigger fetches / Number of events fetched in the last `event trigger fetch`
- [x] Event Triggers: Number of event trigger HTTP workers in process
- [x] Event Triggers: Avg event trigger lock time (if an event has been fetched but not processed because http worker is not free)
#### Sample response
The metrics can be viewed from the `/dev/ekg` endpoint
```json
{
"num_events_fetched":{
"max":0,
"mean":0,
"count":1,
"min":0,
"variance":null,
"type":"d",
"sum":0
},
"num_event_trigger_http_workers":{
"type":"g",
"val":0
},
"event_lock_time":{
"max":0,
"mean":0,
"count":0,
"min":0,
"variance":0,
"type":"d",
"sum":0
},
```
#### Todo
- [ ] Group similar metrics together (Eg: Group all the metrics related to Event trigger, How do we do it??)
Closes: https://github.com/hasura/graphql-engine-mono/issues/202
GitOrigin-RevId: bada11d871272b04c8a09d006d9d037a8464a472
Provides queries for fetching and inserting metadata into that database that do not assume there is a `resource_version` column. This means that will work when migrating to/from older versions.
Co-authored-by: Lyndon Maydwell <92299+sordina@users.noreply.github.com>
GitOrigin-RevId: dac636d530524082c5a13ae0f016a2d4ced16f7f
Add optimistic concurrency control to the ‘replace_metadata’ call.
Prevents users from submitting out-of-date metadata to metadata-mutating APIs.
See https://github.com/hasura/graphql-engine-mono/issues/472 for details.
GitOrigin-RevId: 5f220f347a3eba288a9098b01e9913ffd7e38166
