Make the Dummy isolation provider follow the rest of the isolation
providers and perform the second part of the conversion on the host. The
first part of the conversion is just a dummy script that reads a file
from stdin and prints pixels to stdout.
Make the dummy provider behave a bit more like the other providers, with
a proper function and termination logic. This will be helpful soon in
the tests.
Start the conversion process in a new session, so that we can later on
kill the process group, without killing the controlling script (i.e.,
the Dangezone UI). This should not affect the conversion process in any
other way.
Extend the IsolationProvider class with a
`terminate_doc_to_pixels_proc()` method, which must be implemented by
the Qubes/Container providers and gracefully terminate a process started
for the doc to pixels phase.
Refs #563
Pass the Document instance that will be converted to the
`IsolationProvider.start_doc_to_pixels_proc()` method. Concrete classes
can then associate this name with the started process, so that they can
later on kill it.
Merge Qubes and Containers isolation providers core code into the class
parent IsolationProviders abstract class.
This is done by streaming pages in containers for exclusively in first
conversion process. The commit is rather large due to the multiple
interdependencies of the code, making it difficult to split into various
commits.
The main conversion method (_convert) now in the superclass simply calls
two methods:
- doc_to_pixels()
- pixels_to_pdf()
Critically, doc_to_pixels is implemented in the superclass, diverging
only in a specialized method called "start_doc_to_pixels_proc()". This
method obtains the process responsible that communicates with the
isolation provider (container / disp VM) via `podman/docker` and qrexec
on Containers and Qubes respectively.
Known regressions:
- progress reports stopped working on containers
Fixes#443
stdout_callback is used to flow progress information from the conversion
to some front-end. It was always used in tandem with printing to the
terminal (which is kind of a front-end). So it made sense to put them
always together.
Due to a bump in our Python dependencies, we now install Mypy 1.1.1
instead of 0.982. This change triggered the following errors:
* Incompatible default for argument <a> (default has type
None, argument has type <t>):
Mypy further explains here that PEP 484 prohibits implicit Optional,
so we need to make these types explicit Optional.
* Unused "type: ignore" comment, use narrower [method-assign] instead of
[assignment]:
Mypy has specialized some of its lints, meaning that we should switch
to the newer variants.
Also, it detected several other small inconsistencies. We fix all of
these errors in this commit.
