Bug 127924 – WebKit Bot Watcher's Dashboard: Teach JSON.load() to take optional failure callback function

• Status: RESOLVED
• Resolution: FIXED
• Component: Tools / Tests

[Daniel Bates]

We should have JSON.load() take an optional failure callback function that is invoked whenever a load error or JSON parsing error occurs.

One use case of the optional failure callback can up in bug #127784  to check whether a load failed due to an authentication error toward avoiding excessively prompting a person for credentials.

[Daniel Bates]

Created attachment 222690 [details]
Patch

[Alexey Proskuryakov]

Comment on attachment 222690 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=222690&action=review

Looks good to me overall. I'm asking for a number of changes though, so it would be beneficial to have another patch posted before landing.

> Tools/BuildSlaveSupport/build.webkit.org-config/public_html/dashboard/Scripts/BuildbotIteration.js:354
> +        }.bind(this), function(data) {

Could you please split this into two lines? This looks somewhat confusing as it is, with two distinct large functions that get to share one line of code.

> Tools/BuildSlaveSupport/build.webkit.org-config/public_html/dashboard/Scripts/Utilities.js:27
> +JSON.LoadError = 1 << 0;
> +JSON.ParseError = 1 << 1;

Other code in the Dashboard uses string names for everything, I don't think that a bitmask fits the purpose well.

It's not used as a bitmask either.

> Tools/BuildSlaveSupport/build.webkit.org-config/public_html/dashboard/Scripts/Utilities.js:59
> +            parseErrorOccurred = true;

Why not just invoke failureCallback here, and have an early return? That should save us the need to track a state variable.

> Tools/BuildSlaveSupport/build.webkit.org-config/public_html/dashboard/Scripts/Utilities.js:63
> +            failureCallback(data);

This will fail if there is no failureCallback, unlike above code that checks for its type.

[Alexey Proskuryakov]

You could also utilize the trick you did before, and assign failureCallback to a no-op function if it's not what we expect.

[Daniel Bates]

Created attachment 222713 [details]
Patch

Updated patch according to Alexey Proskuryakov's remarks.

[Daniel Bates]

Committed r163196: <http://trac.webkit.org/changeset/163196>