[logdog-stream-view] Fix loading loop.

[logdog-stream-view] Fix loading loop.

Fix the log loading loop construction for LogDog stream view. The
current form included indefinite recursion and no clear terminal point.
This is an artifact of the transition to async notation.

Now, an operation is scoped to the lifecycle of its initiating request,
regardless of how many fetches it is composed of. The fetch loop is
clearly defined in a "for" loop that performs the fetch cycle repeatedly
until a terminal condition is hit.

The "been a while" timer is now fully scoped to a given fetch loop,
avoiding a bug where old timers would trigger during later cycles,
maintaining a near-perpetual state of "been a while" messaging
regardless of log throughput.

BUG=None
TEST=local
  - Ran in local browser against development instance, works.

Review-Url: https://codereview.chromium.org/2893783002
Committed: https://github.com/luci/luci-go/commit/3b355f68555a714a8d42b180785d16f9c67eb6d3

[dnj, 2017-05-18 01:19:47]

dnj@chromium.org changed reviewers:
+ hinoka@chromium.org

[dnj, 2017-05-18 01:19:47]

PTAL

[Ryan Tseng, 2017-05-18 01:50:11]

hinoka@google.com changed reviewers:
+ hinoka@google.com

[Ryan Tseng, 2017-05-18 01:50:12]

lgtm

i like the loop better than the tail call.

[dnj, 2017-05-18 01:52:15]

The CQ bit was checked by dnj@chromium.org

[commit-bot: I haz the power, 2017-05-18 01:52:26]

CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-05-18 01:59:57]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1495072335715390, "parent_rev":
"a5d341b60c0d141e31dbe2cc5509f9ccfaba6733", "commit_rev":
"3b355f68555a714a8d42b180785d16f9c67eb6d3"}

[commit-bot: I haz the power, 2017-05-18 02:00:00]

Description was changed from

==========
[logdog-stream-view] Fix loading loop.

Fix the log loading loop construction for LogDog stream view. The
current form included indefinite recursion and no clear terminal point.
This is an artifact of the transition to async notation.

Now, an operation is scoped to the lifecycle of its initiating request,
regardless of how many fetches it is composed of. The fetch loop is
clearly defined in a "for" loop that performs the fetch cycle repeatedly
until a terminal condition is hit.

The "been a while" timer is now fully scoped to a given fetch loop,
avoiding a bug where old timers would trigger during later cycles,
maintaining a near-perpetual state of "been a while" messaging
regardless of log throughput.

BUG=None
TEST=local
  - Ran in local browser against development instance, works.
==========

to

==========
[logdog-stream-view] Fix loading loop.

Fix the log loading loop construction for LogDog stream view. The
current form included indefinite recursion and no clear terminal point.
This is an artifact of the transition to async notation.

Now, an operation is scoped to the lifecycle of its initiating request,
regardless of how many fetches it is composed of. The fetch loop is
clearly defined in a "for" loop that performs the fetch cycle repeatedly
until a terminal condition is hit.

The "been a while" timer is now fully scoped to a given fetch loop,
avoiding a bug where old timers would trigger during later cycles,
maintaining a near-perpetual state of "been a while" messaging
regardless of log throughput.

BUG=None
TEST=local
  - Ran in local browser against development instance, works.

Review-Url: https://codereview.chromium.org/2893783002
Committed:
https://github.com/luci/luci-go/commit/3b355f68555a714a8d42b180785d16f9c67eb6d3
==========

[commit-bot: I haz the power, 2017-05-18 02:00:01]

Committed patchset #1 (id:1) as
https://github.com/luci/luci-go/commit/3b355f68555a714a8d42b180785d16f9c67eb6d3