This is the result of a general audit of how we fork threads, with a
detour into how we're using mutable state especially in websocket
codepaths, making more robust to async exceptions and exceptions
resulting from bugs.
Some highlights:
- use a wrapper around 'immortal' so threads that die due to bugs are
restarted, and log the error
- use 'withAsync' some places
- use bracket a few places where we might break invariants
- log some codepaths that represent bugs
- export UnstructuredLog for ad hoc logging (the alternative is we
continue not logging useful stuff)
I had to timebox this. There are a few TODOs I didn't want to address.
And we'll wait until this is merged to attempt #3705 for
Control.Concurrent.Extended
We upload a set of accumulating timers and counters to track service
time for different types of operations, across several dimensions (e.g.
did we hit the plan cache, was a remote involved, etc.)
Also...
Standardize on DiffTime as a standard duration type, and try to use it
consistently.
See discussion here:
https://github.com/hasura/graphql-engine/pull/3584#pullrequestreview-340679369
It should be possible to overwrite that module so the new threadDelay
sticks per the pattern in #3705 blocked on #3558
Rename the Control.Concurrent.Extended.threadDelay to `sleep` since a
naive use with a literal argument would be very bad!
We catch a bug in 'computeTimeDiff'.
Add convenient 'Read' instances to the time unit utility types. Make
'Second' a newtype to support this.
* 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
The API:
1. HGE has `--jwt-secret` flag or `HASURA_GRAPHQL_JWT_SECRET` env var. The value of which is a JSON.
2. The structure of this JSON is: `{"type": "<standard-JWT-algorithms>", "key": "<the-key>"}`
`type` : Standard JWT algos : `HS256`, `RS256`, `RS512` etc. (see jwt.io).
`key`:
i. Incase of symmetric key, the key as it is.
ii. Incase of asymmetric keys, only the public key, in a PEM encoded string or as a X509 certificate.
3. The claims in the JWT token must contain the following:
i. `x-hasura-default-role` field: default role of that user
ii. `x-hasura-allowed-roles` : A list of allowed roles for the user. The default role is overriden by `x-hasura-role` header.
4. The claims in the JWT token, can have other `x-hasura-*` fields where their values can only be strings.
5. The JWT tokens are sent as `Authorization: Bearer <token>` headers.
---
To test:
1. Generate a shared secret (for HMAC-SHA256) or RSA key pair.
2. Goto https://jwt.io/ , add the keys
3. Edit the claims to have `x-hasura-role` (mandatory) and other `x-hasura-*` fields. Add permissions related to the claims to test permissions.
4. Start HGE with `--jwt-secret` flag or `HASURA_GRAPHQL_JWT_SECRET` env var, which takes a JSON string: `{"type": "HS256", "key": "mylongsharedsecret"}` or `{"type":"RS256", "key": "<PEM-encoded-public-key>"}`
5. Copy the JWT token from jwt.io and use it in the `Authorization: Bearer <token>` header.
---
TODO: Support EC public keys. It is blocked on frasertweedale/hs-jose#61
