Add support for Pull Queues to prod implementation.

Add support for Pull Queues to prod implementation.

This CL adds the interface (corresponding to native one) and prod
implementation. Memory implementation will be in a separate CL.

R=iannucci@chromium.org
BUG=

Committed: https://github.com/luci/gae/commit/8ddad9162eff4fcb3c15f7cb0ac61fda3857565a

[Vadim Sh., 2016-11-18 03:42:12]

PTAL, this is mostly boilerplate to make impl/memory CL smaller.

https://codereview.chromium.org/2512093002/diff/1/service/taskqueue/interface.go
File service/taskqueue/interface.go (right):

https://codereview.chromium.org/2512093002/diff/1/service/taskqueue/interface...
service/taskqueue/interface.go:77: // Lease leases tasks from a queue.
all docs are copy-paste from official site

https://codereview.chromium.org/2512093002/diff/1/service/taskqueue/interface...
service/taskqueue/interface.go:87: // If tag is empty, then the returned tasks
are grouped by the tag of the task
:( why they did it, I'll have to reimplement all this in impl/memory

[Vadim Sh., 2016-11-18 03:53:53]

https://codereview.chromium.org/2512093002/diff/1/service/taskqueue/interface.go
File service/taskqueue/interface.go (right):

https://codereview.chromium.org/2512093002/diff/1/service/taskqueue/interface...
service/taskqueue/interface.go:79: // leaseTime is in seconds. The number of
tasks fetched will be at most
actually int for leaseTime is BS, I'll convert it to time.Duration and clarify
that it has second precision.

[Vadim Sh., 2016-11-18 04:04:00]

Description was changed from

==========
Add support for Pull Queues to prod implementation.

This CL adds the interface (100% corresponding to native one) and prod
implementation. Memory implementation will be in a separate CL.

R=iannucci@chromium.org
BUG=
==========

to

==========
Add support for Pull Queues to prod implementation.

This CL adds the interface (corresponding to native one) and prod
implementation. Memory implementation will be in a separate CL.

R=iannucci@chromium.org
BUG=
==========

[Vadim Sh., 2016-11-18 04:04:56]

Switched to time.Duration instead of int for leaseTime.

[iannucci, 2016-11-18 05:21:13]

lgtm

[Vadim Sh., 2016-11-18 19:52:02]

The CQ bit was checked by vadimsh@chromium.org

[commit-bot: I haz the power, 2016-11-18 19:52:06]

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, 2016-11-18 19:56:24]

Description was changed from

==========
Add support for Pull Queues to prod implementation.

This CL adds the interface (corresponding to native one) and prod
implementation. Memory implementation will be in a separate CL.

R=iannucci@chromium.org
BUG=
==========

to

==========
Add support for Pull Queues to prod implementation.

This CL adds the interface (corresponding to native one) and prod
implementation. Memory implementation will be in a separate CL.

R=iannucci@chromium.org
BUG=

Committed:
https://github.com/luci/gae/commit/8ddad9162eff4fcb3c15f7cb0ac61fda3857565a
==========

[commit-bot: I haz the power, 2016-11-18 19:56:25]

Committed patchset #2 (id:20001) as
https://github.com/luci/gae/commit/8ddad9162eff4fcb3c15f7cb0ac61fda3857565a