Asset discovery networkIdleTimeout not being applied from config

[mweitzel]

The problem

Newly introduced maximum: 750 for discovery.networkIdleTimeout breaks existing builds.

SVGs when inlined as html, instead of referenced via url will render intermittently. Setting a higher timeout was a valid workaround until recently.

There are two issues:
1 - inlined SVG elements will intermittently render at low networkIdleTimeouts
2 - a newly introduced timeout maximum breaks existing builds

In this bug report I'd like to only address the timeout, as it is a recent regression. I can file another bug for the svg issue.

Environment

• Node version:
• @percy/cli version: >= @percy/cli/1.0.0-beta.69
• Version of Percy SDK you’re using: ruby/rails sdk
• OS version: linux-x64
• Type of shell command-line [interface]: sh %(#{PERCY_AGENT_BIN} exec -t 1500 -- rspec --tag visual)
• build IDs illustrating intermittent svg rendering with lower timeout: 14108483, 14137118

Details

Historically our inlined SVG elements will not render consistently with lower timeouts. After upgrading from beta.68 to beta.69 or beta.70 the problem was re-introduced.

Commit introducing the issue 3c0c0bd

Debug logs

$ bundle exec rake percy:snapshots                                                                                                                                                                                                                                                                                
[redacted]/node_modules/.bin/percy exec -t 1500 --debug -- rspec --tag visual                                                                                                                                                                                                  
[percy:config] Config file not found (0ms)                                                                                                                                                                                                                                                                               
[percy:config] Invalid config: (15ms)                                                                                                                                                                                                                                                                                    
[percy:config] - discovery.networkIdleTimeout: must be <= 750 (0ms)                                                                                                                                                                                                                                                      
[percy:config] Using config:                                                                                                                                                                                                                                                                                             
{                                                                                                                                                                                                                                                                                                                        
  discovery: {                                                                                                                                                                                                                                                                                                           
    networkIdleTimeout: 750                                                                                                                                                                                                                                                                                              
  }                                                                                                                                                                                                                                                                                                                      
} (1ms)              
...     
...                     

Code to reproduce issue

Run a snapshot with an inlined svg on version beta.69 or above.

[Robdel12]

Hey @mweitzel! This was a very intentional change, any network idle timeout higher than 750ms is an issue that's likely being band aided over by adding more time to each widths asset discovery. Setting it to 1500 means each width by minimum was going to take 1.5 seconds (and likely longer, since there will be requests that are made in that initial second). That's at least 3 seconds of just waiting for idle with the default snapshot width config, per-snapshot.

Can you share --debug logs of a test run that fails to discover the SVG that's a background image? Seems very odd that the SVG wouldn't be requested by the browser within 750ms of loading. Might also be worth observing what the asset discovery browser looks like for the snapshots that are missing SVGs

[Robdel12]

👋🏼 After catching up on a bunch of things after the long break, I was able to confirm this is a pretty big bug. I have a fix but want to make sure this is tested, too. #643

[Robdel12]

Thanks for reporting this! Should be fixed in v1.0.0-beta.71 👀

[Pomax]

Hm, I just noticed this with beta 71 installed, so might not quite be fixed?

package.json:

  "scripts": {
    ...
    "percy": "percy exec -t 800 -- npm run playwright:ci",
    ...
  },
  ...
  "devDependencies": {
    "@percy/cli": "^1.0.0-beta.71",
    ...

and github action log:

[percy] Invalid config:
[percy] - discovery.networkIdleTimeout: must be <= 750
[percy] Downloading Chromium 885264...
[percy] Successfully downloaded Chromium 885264
[percy] Percy has started!
[percy] Running "npm run playwright:ci"

[Robdel12]

750 is the expected max, that won't change.

The bug that was fixed was the idle timeout actually not being applied

[Pomax]

I see, thanks.

[Robdel12]

Since you can't mark threaded replies as an answer, this was resolved with #643.