[Notes] [Git][BuildStream/buildstream][willsalmon/trackWarning] 18 commi

Will Salmon pushed to branch willsalmon/trackWarning at BuildStream / buildstream

Commits:

3d308894

by Richard Maw at 2018-07-31T16:31:36Z

element.py: Cache the result of checking whether an artifact is cached weakly

Normally we'd only need it in the case of scheduling a weakly cached build,
but to allow caching of failed builds we need to be able to distinguish
between cached successes and cached failures
for both strong and weak cache keys.

To allow other cache lookup codepaths to look up via the weak key
requires changes through the call stack to consult which key to use,
and cache invalidation of the saved state when it changes.

b3a68e28

by Richard Maw at 2018-07-31T16:31:36Z

element.py: Add metadata to distinguish between successful and failed builds

This just puts the metadata in place,
we're adding code paths to add failed builds later.

f4573df3

by Richard Maw at 2018-07-31T16:31:36Z

Convert call-sites of Element._cached() that assume success

When we later add cached failures it needs to not treat them as successes.

553df108

by Richard Maw at 2018-07-31T16:31:36Z

_frontend/widget.py: Render cached failures differently to successes

d14d8ee2

by Richard Maw at 2018-07-31T16:32:35Z

Cache failed builds

This creates an artifact when element assembly fails too,
and if it's the right kind of exception uses the now-included install directory
similarly to if it had returned successfully.

If there's a failure during install the artifact contains any installed files,
but may contain nothing at all.

d83122bb

by Richard Maw at 2018-07-31T16:32:35Z

_scheduler/queues/buildqueue.py: Skip rebuilding cached failures

This flags up a failure and if run in an interactive prompt
permits the user to attempt a rebuild.

78944e9a
by Richard Maw at 2018-07-31T16:32:35Z
```
tests: Add tests for cached behaviours
```

3fa79d8d

by Richard Maw at 2018-07-31T16:32:35Z

_scheduler/queues: Add failed builds to "done" queue

This allows the scheduler to move jobs from the current queue to the next.

As a result of this change later queues than the build queue
mustn't skip a cached failure, so the logic is specialised to build queues only.

e8cd43dc

by Richard Maw at 2018-07-31T16:32:58Z

NEWS: Describe caching of failures

Closes #76.

88cd61ea

by knownexus at 2018-07-31T16:32:58Z

Added the missing `_get_build_log` function

4fc1f5d1

by Phillip Smyth at 2018-07-31T17:17:34Z

Merge branch 'richardmaw/cache-fail' into 'master'

Store failed builds in the cache

Closes #76

See merge request BuildStream/buildstream!475

6cd3df09