Instead of transmitting stage metadata over a socket and then
writing it via `Object.meta.write`, use the latter and bind
mount the corresponding file into the stage so it can directly
be written to from the stage. Change `api.metadata` to do so,
which means that this change is transparent for the stages.
Now that arguments are transmitted via a mapped, i.e. bind-mounted,
file instead of using the jsoncomm RPC mechanism, all the methods
related to the latter can be removed from API.
Use `traceback.print_tb()` to serialize the exceptions' backtrace.
The previously used expression `str(e.__traceback__)` will just
give `<traceback object at 0x…>`, which is not very helpful.
Add a test to check that the method name that raises the exception,
also called `exception`, is in the traceback.
When using `str(type(exception))` this ends up to be something like
`<class 'ValueError'>` for a `ValueError` exception. Get the vanilla
name of the exception type via `type(exception).__name__`.
Add a test to ensure that we encode this properly.
Rename the `API.exception` member to `API.error`, to make it more
generic, so it can also be used for other sort of errors in the
future. Also add a layer of additional structure with `type` and
`data` members so different types of errors apart. Currently only
`exception` is used.
Adapt the tests in test/mod/test_api.py to check for the new
structure and its content.
The `api.exception` method, which is internally also used by
`api.exception_handler` helper, calls `sys.exit` and this no
statement after a call to either method should be reached.
Add an assertion to make sure of that.
Create a new api endpoint called exception, that communicates
exception backtraces separately back to osbuild, as opposed to
dumping them into the normal log. Additionally, add a corresponding
test to check that a call to api.exception correctly sets
API.exception.
Access metadata.api only after `api` has exited the context and
thus the event loop has stopped and all incoming messages, like
the one setting the metadata, have been processed.
See commit 803433fb62 for a lecture
about the internals and all the details involved.
Simple check for the new server side method, `get-arguments`, and
client side counterpart, `api.arguments`, that compares that using
the later we get the supplied input (arguments) to API.
Now that jsoncomm is using a connection oriented protocol, the
`addr` parameter is not needed[*] and can thus be removed from
the `BaseAPI._message` message dispatcher. Adapt all usages
of it, including the tests.
[*] sendmsg ignores the destination parameter for connection
oriented sockets.
Add a new abstract class property to `BaseAPI` called `endpoint`,
meant to be implemented by deriving classes in order to identify
the end point name for the API provider.
Implement the new property in all existing API providers.
