Implement a new error handling library based on pkg/errors. It provides
stack saving on wrapping and exports some function to add stack saving
also to external errors.
It also implements custom zerolog error formatting without adding too
much verbosity by just printing the chain error file:line without a full
stack trace of every error.
* Add a --detailed-errors options to print error with they full chain
* Wrap all error returns. Use errors.WithStack to wrap without adding a
new messsage and error.Wrap[f] to add a message.
* Add golangci-lint wrapcheck to check that external packages errors are
wrapped. This won't check that internal packages error are wrapped.
But we want also to ensure this case so we'll have to find something
else to check also these.
Replace zap with zerolog.
zerolog has a cleaner interface and can be easily configured with custom
error chain printing using a new error handling library that will be
implemented in another PR.
* Create an APIError that should only be used for api returned errors.
It'll wrap an error and can have different Kinds and optional code and
message.
* The http handlers will use the first APIError available in the
error chain and generate a json response body containing the code and
the user message. The wrapped error is internal and is not sent in the
response.
If no api error is available in the chain a generic internal
server error will be returned.
* Add a RemoteError type that will be created from remote services calls
(runservice, configstore). It's similar to the APIError but a
different type to not propagate to the caller response and it'll not
contain any wrapped error.
* Gateway: when we call a remote service, by default, we'll create a
APIError using the RemoteError Kind (omitting the code and the
message that usually must not be propagated).
This is done for all the remote service calls as a starting point, in
future, if this default behavior is not the right one for a specific
remote service call, a new api error with a different kind and/or
augmented with the calling service error codes and user messages could
be created.
* datamanager: Use a dedicated ErrNotExist (and converting objectstorage
ErrNotExist).
Explicitly write and flush the headers in the various services LogHandlers.
Currently the 200 response and the other headers will be automatically written
by the golang http implementation only when we send something in the body. But if
there's nothing to send (no logs yet written) the client will never receive the
headers and cannot know if the request was successful.
* return errNotExist in readTaskLogs when the executor task doesn't exist: so
the client will receive a 404 instead of a 500 (since a generic error will be
mapped to a 500).
* Wrap the errNotExist returned by readTaskLogs with a new ErrNotExits reporting
"log doesn't exist"
* objectstorage: remove `types` package and move `ErrNotExist` in base package
* objectstorage: Implement .Is and add helper `IsErrNotExist` for `ErrNotExist`
* util: Rename `ErrNotFound` to `ErrNotExist`
* util: Add `IsErr*` helpers and use them in place of `errors.Is()`
* datamanager: add `ErrNoDataStatus` to report when there's not data status in ost
* runservice/common: remove `ErrNotExist` and use errors in util package
Reorganize ExecutorTask to better distinguish between the task Spec and
the Status.
Split the task Spec in a sub part called ExecutorTaskSpecData that contains
tasks data that don't have to be saved in etcd because it contains data that can
be very big and can be generated starting from the run and the runconfig.
Export clients and related packages.
The main rule is to not import internal packages from exported packages.
The gateway client and related types are totally decoupled from the gateway
service (not shared types between the client and the server).
Instead the configstore and the runservice client currently share many types
that are now exported (decoupling them will require that a lot of types must be
duplicated and the need of functions to convert between them, this will be done
in future when the APIs will be declared as stable).
Implement runservice maintenance mode and export/import.
When runservice is set in maintenance mode it'll start only the maintenance and
export/import handlers.
Setting maintenance mode will set a key in etcd so all the runservice instances
will detect it and enter in maintenance mode. This is done asyncronously so it
could take some time (future improvements will add some api to show all the
runservice states)
Export is always available and will export the datamanager contents. Currently
only datamanager contents are exported (no logs and workspace archives).
Import is available only during maintenance, given a datamanager export will
import it and reset etcd to this import state.
Use the go sql context functions (ExecContext, QueryContext etc...)
The context is saved inside Tx so the library users should only pass it one time
to the db.Do function.
The cache group fields defines under which cache group the run cache data will
belong. This is needed/useful for some next changes:
* Make cache correctly work for user direct runs. Since the user direct runs all
belong to the same run group (the user id) all the use direct runs will share the
same caches. To distinguish between the different caches we need to use something
in addition to the user id (the local repo uuid generated by the direct run
start command)
* Share the cache between multiple projects
ErrInternal is an internal error that should be provided to the user (http api
will return a 500 with the error message)
It'll be used for any kind of error that are not auth or bad requests (like
errors to communicate to another service)
Don't create an ErrFromRemote wrapping the returned error but
wrap the ErrFromRemote
Also use xerrors Is/As to get the underlying error to return to api clients
while maintaining context for logging
Just a raw replace of "github.com/pkg/errors".
Next steps will improve errors (like remote errors, api errors, not exist errors
etc...) to leverage its functionalities
rename the previous posix storage to posixflat and make it currently not user
selectable (since I'm not sure it's really worth using it).
The new posix storage uses the filesystem without any escaping so it's not a
real flat namespace.
This isn't a real issue since also minio is not a flat namespace and we are so
forced to use it like a hierarchycal filesystem.
Logs and archives can be shared by multiple runs. So removing a run doesn't
imply that we could also remote the logs and archives since they could be
"referenced" by another run.
Store also the runids as specific objects along with the logs and archives so,
we'll remove them only when no runids objects exist.
Also if they are logically part of the runservice the names runserviceExecutor
and runserviceScheduler are long and quite confusing for an external user
Simplify them separating both the code parts and updating the names:
runserviceScheduler -> runservice
runserviceExecutor -> executor
Simone Gotti
Carlo Mandelli