* 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).
Replace https://github.com/satori/go.uuid with maintained version at
https://github.com/gofrs/uuid
Since the new version uuid.NewV4 returns an error when failing to read
from the random source reader we use uuid.Must to panic on error since
it's considered an unrecoverable error.
In future, if needed, we could handle the error instead of panicking.
* 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
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).
Since they're not types common to all the services but belongs to the
configstore.
Next step will be to make them local to the configstore and not directly used by
other services since these types are also stored.
Implement configstore maintenance mode and export/import.
When configstore 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 configstore 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
configstore states)
Export is always available and will export the datamanager contents.
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.
* Override the provided remotesource id with the current one (it could not be
provided or provided with a different id but the remotesource ref is the way to
get the current remote source).
* When changing remotesource name check that a remote source with the new name
does not already exist.
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
Simone Gotti