Public bug reported: [Impact]
* livecd-rootfs builds will fail immediately when a snap-tool invocation fails to contact the snapstore because of ephemeral connection problems or a transient error on the server side. * The snap-tool script included with livecd-rootfs in Eoan has been enhanced to retry on connection errors and 5xx server errors reducing the likelihood of image builds breaking due to a flaky connection or a server hiccup. [Test Cases] * Download core, core18 snaps using both `snap download <snap-name>` and `snap-tool download <snap-name>` and make sure the downloads are identical. * Invoke `snap-tool info <snap-name>` for a few snaps, e.g. review- gator, lpshipit, azure-cli and verify that all fields carry correct information. * Test the backoff/retry logic using the following procedure: Make netcat listen on port 12345 netcat -l -p 12345 Create a symlink from snaptool.py to snap-tool and import the ExpBackoffHTTPClient class from a Python session: ln -s snap-tool snaptool.py python3 from snaptool import ExpBackoffHTTPClient http_client = ExpBackoffHTTPClient() request = http_client.get("http://127.0.0.1:12345/") request.text() Go back to the terminal where you invoked netcat and stop it. snap-tool should print the following and then fail: WARNING: failed to open URL 'http://127.0.0.1:12345/': Remote end closed connection without response Retrying HTTP request in 2 seconds... WARNING: failed to open URL 'http://127.0.0.1:12345/': <urlopen error [Errno 111] Connection refused> Retrying HTTP request in 4 seconds... Repeat the procedure above but instead of stopping netcat, paste the following response: HTTP/1.1 503 Error and hit enter twice. You should see WARNING: failed to open URL 'http://127.0.0.1:12345/': HTTP Error 503: Error Retrying HTTP request in 2 seconds... Repeat the above pasting "HTTP/1.1 404 Not found" instead. The snap-tool should fail immediately. [Regression Potential] * Tool logic and http request headers/body are unchanged, only the way connections are built has been modified. The expectation is that this will be more robust and testing in devel hasn't surfaced any bugs, but there is a slight risk that the tool's behavior has changed in unobvious corner cases that were missed during testing. ** Affects: livecd-rootfs (Ubuntu) Importance: Undecided Status: In Progress ** Tags: id-5d0a349876579b42ed84d920 ** Summary changed: - Backport snap-tool backoff/retry logic + Add retry logic to snap-tool to make downloads more resilient -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1837871 Title: Add retry logic to snap-tool to make downloads more resilient To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/livecd-rootfs/+bug/1837871/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs