### What needs to get done When using `remote-build` service in `rockcraft`, there are often build failures caused by network instabilities. The network instability causes the unhandled `ChunkedEncodingError` exception inside `craft_application/services/request.py", line 71, in download_chunks`. When the `*craft` tool is downloading the artifact from the build farm, it should be able to retry upon broken connections, such that when using `*craft` tools in CI, the occasional failures happening during the download would not lead to a full rebuild. A log of such an error is attached below: ``` 2026-01-23 17:16:25.270 Succeeded: amd64, arm64, armhf, ppc64el, riscv64, s390x 2026-01-23 17:16:25.271 Fetching build artifacts... 2026-01-23 17:16:31.933 Downloading 6 files (--->) 2026-01-23 17:17:38.222 Downloading 6 files (<---) 2026-01-23 17:17:38.228 rockcraft internal error: ChunkedEncodingError(ProtocolError('Connection broken: IncompleteRead(14610378 bytes read, 25147446 more expected)', IncompleteRead(14610378 bytes read, 25147446 more expected))) 2026-01-23 17:17:38.255 Traceback (most recent call last): 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/urllib3/response.py", line 779, in _error_catcher 2026-01-23 17:17:38.255 yield 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/urllib3/response.py", line 904, in _raw_read 2026-01-23 17:17:38.255 data = self._fp_read(amt, read1=read1) if not fp_closed else b"" 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/urllib3/response.py", line 887, in _fp_read 2026-01-23 17:17:38.255 return self._fp.read(amt) if amt is not None else self._fp.read() 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/current/usr/lib/python3.12/http/client.py", line 495, in read 2026-01-23 17:17:38.255 s = self._safe_read(self.length) 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/current/usr/lib/python3.12/http/client.py", line 642, in _safe_read 2026-01-23 17:17:38.255 raise IncompleteRead(data, amt-len(data)) 2026-01-23 17:17:38.255 http.client.IncompleteRead: IncompleteRead(14610378 bytes read, 25147446 more expected) 2026-01-23 17:17:38.255 2026-01-23 17:17:38.255 The above exception was the direct cause of the following exception: 2026-01-23 17:17:38.255 Traceback (most recent call last): 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/requests/models.py", line 820, in generate 2026-01-23 17:17:38.255 yield from self.raw.stream(chunk_size, decode_content=True) 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/urllib3/response.py", line 1091, in stream 2026-01-23 17:17:38.255 data = self.read(amt=amt, decode_content=decode_content) 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/urllib3/response.py", line 980, in read 2026-01-23 17:17:38.255 data = self._raw_read(amt) 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/urllib3/response.py", line 903, in _raw_read 2026-01-23 17:17:38.255 with self._error_catcher(): 2026-01-23 17:17:38.255 File "/snap/rockcraft/current/usr/lib/python3.12/contextlib.py", line 158, in __exit__ 2026-01-23 17:17:38.255 self.gen.throw(value) 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/urllib3/response.py", line 806, in _error_catcher 2026-01-23 17:17:38.255 raise ProtocolError(f"Connection broken: {e!r}", e) from e 2026-01-23 17:17:38.255 urllib3.exceptions.ProtocolError: ('Connection broken: IncompleteRead(14610378 bytes read, 25147446 more expected)', IncompleteRead(14610378 bytes read, 25147446 more expected)) 2026-01-23 17:17:38.255 2026-01-23 17:17:38.255 During handling of the above exception, another exception occurred: 2026-01-23 17:17:38.255 Traceback (most recent call last): 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/craft_application/application.py", line 669, in run 2026-01-23 17:17:38.255 return_code = self._run_inner() 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/craft_application/application.py", line 646, in _run_inner 2026-01-23 17:17:38.255 return_code = dispatcher.run() or os.EX_OK 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/craft_cli/dispatcher.py", line 564, in run 2026-01-23 17:17:38.255 return self._loaded_command.run(self._parsed_command_args) 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/craft_application/commands/base.py", line 222, in run 2026-01-23 17:17:38.255 result = self._run(parsed_args, **kwargs) or result 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/craft_application/commands/remote.py", line 165, in _run 2026-01-23 17:17:38.255 returncode = self._monitor_and_complete(builds=builds) 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/craft_application/commands/remote.py", line 224, in _monitor_and_complete 2026-01-23 17:17:38.255 artifacts = builder.fetch_artifacts(pathlib.Path.cwd()) 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/craft_application/services/remotebuild.py", line 207, in fetch_artifacts 2026-01-23 17:17:38.255 return self.request.download_files_with_progress(artifact_downloads).values() 2026-01-23 17:17:38.255 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/craft_application/services/request.py", line 109, in download_files_with_progress 2026-01-23 17:17:38.255 for chunk_size in dl: 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/craft_application/services/request.py", line 71, in download_chunks 2026-01-23 17:17:38.255 for chunk in download.iter_content(None): 2026-01-23 17:17:38.255 File "/snap/rockcraft/3974/lib/python3.12/site-packages/requests/models.py", line 822, in generate 2026-01-23 17:17:38.255 raise ChunkedEncodingError(e) 2026-01-23 17:17:38.255 requests.exceptions.ChunkedEncodingError: ('Connection broken: IncompleteRead(14610378 bytes read, 25147446 more expected)', IncompleteRead(14610378 bytes read, 25147446 more expected)) ``` ### Why it needs to get done As `remote-build` can take a long time to be built, purging a successful build with a single failed download attempt seems very inefficient and wasteful. We should let `*craft` tools give multiple tries to improve the chances of successful builds.