tokenserver: Boilerplate for loading and serving service_accounts.cfg.

tokenserver: Boilerplate for loading and serving service_accounts.cfg.

It closely resembles handling of delegation.cfg config file. In particular,
it reuses most of the logic through policy.Policy class.

R=smut@google.com
BUG=731843
Review-Url: https://codereview.chromium.org/2993023002
Committed: https://github.com/luci/luci-go/commit/944bd62ef8c6c11817b6cb7fccd1a84f5f8af7e8

[Vadim Sh., 2017-08-04 02:25:13]

https://codereview.chromium.org/2993023002/diff/20001/tokenserver/appengine/i...
File tokenserver/appengine/impl/serviceaccounts/config.go (right):

https://codereview.chromium.org/2993023002/diff/20001/tokenserver/appengine/i...
tokenserver/appengine/impl/serviceaccounts/config.go:1: // Copyright 2017 The
LUCI Authors.
this file resembles
https://github.com/luci/luci-go/blob/master/tokenserver/appengine/impl/delega...

https://codereview.chromium.org/2993023002/diff/20001/tokenserver/appengine/i...
tokenserver/appengine/impl/serviceaccounts/config.go:64: policy: policy.Policy{
https://godoc.org/github.com/luci/luci-go/tokenserver/appengine/impl/utils/po...

It manages in-memory cache with parsed service_accounts.cfg, occasionally
refetching it from datastore.

https://codereview.chromium.org/2993023002/diff/20001/tokenserver/appengine/i...
File tokenserver/appengine/impl/serviceaccounts/config_test.go (right):

https://codereview.chromium.org/2993023002/diff/20001/tokenserver/appengine/i...
tokenserver/appengine/impl/serviceaccounts/config_test.go:31: Convey("Loads", t,
func() {
there'll be more here eventually

https://codereview.chromium.org/2993023002/diff/20001/tokenserver/appengine/i...
File tokenserver/appengine/impl/services/admin/adminsrv/service.go (right):

https://codereview.chromium.org/2993023002/diff/20001/tokenserver/appengine/i...
tokenserver/appengine/impl/services/admin/adminsrv/service.go:36:
delegation.InspectDelegationTokenRPC
just sorted

[smut, 2017-08-04 22:43:42]

lgtm

https://codereview.chromium.org/2993023002/diff/40001/tokenserver/appengine/i...
File tokenserver/appengine/impl/serviceaccounts/config.go (right):

https://codereview.chromium.org/2993023002/diff/40001/tokenserver/appengine/i...
tokenserver/appengine/impl/serviceaccounts/config.go:101: func prepareRules(cfg
policy.ConfigBundle, revision string) (policy.Queryable, error) {
Is a pointer to a Rules struct a type of policy.Queryable? I'm not sure I see
how the declared return type matches what is being returned.

[Vadim Sh., 2017-08-04 22:49:43]

Description was changed from

==========
tokenserver: Boilerplate for loading and serving service_accounts.cfg.

It is closely resembles handling of delegation.cfg config file. In particular,
it reuses most of the logic through policy.Policy class.

R=smut@google.com
BUG=731843
==========

to

==========
tokenserver: Boilerplate for loading and serving service_accounts.cfg.

It closely resembles handling of delegation.cfg config file. In particular,
it reuses most of the logic through policy.Policy class.

R=smut@google.com
BUG=731843
==========

[Vadim Sh., 2017-08-04 23:25:29]

https://codereview.chromium.org/2993023002/diff/40001/tokenserver/appengine/i...
File tokenserver/appengine/impl/serviceaccounts/config.go (right):

https://codereview.chromium.org/2993023002/diff/40001/tokenserver/appengine/i...
tokenserver/appengine/impl/serviceaccounts/config.go:101: func prepareRules(cfg
policy.ConfigBundle, revision string) (policy.Queryable, error) {
On 2017/08/04 22:43:42, smut wrote:
> Is a pointer to a Rules struct a type of policy.Queryable? I'm not sure I see
> how the declared return type matches what is being returned.

policy.Queryable is defined here:
https://github.com/luci/luci-go/blob/18ae6bdbc6652e10610d55e4528d4bb3c624f813...

Any thing that has 'ConfigRevision() string' method matches this interface.

*Rules does have 'ConfigRevision() string' method (it's defined on line 114),
and thus it matches this interface.

Note that 'Rules{}' by itself (without '&') can't be cast to policy.Queryable,
because the method is defined with the pointer as the receiver. Go doesn't allow
automatic type cast in this case: https://play.golang.org/p/MdP-wR1tNp (I think
because generally non-pointer values don't even guaranteed to have a stable
address, though not sure).

It does allow the reverse though: methods with non-pointer receivers "apply" to
pointer entities: https://play.golang.org/p/yihRcb0YvZ (generally because Go can
always copy the value pointed by the pointer and pass it as the receiver).

Not the best explanation evar, I know...

[Vadim Sh., 2017-08-04 23:25:43]

The CQ bit was checked by vadimsh@chromium.org

[commit-bot: I haz the power, 2017-08-04 23:25:55]

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, 2017-08-04 23:31:07]

CQ is committing da patch.

Bot data: {"patchset_id": 40001, "attempt_start_ts": 1501889143981090,
"parent_rev": "18ae6bdbc6652e10610d55e4528d4bb3c624f813", "commit_rev":
"944bd62ef8c6c11817b6cb7fccd1a84f5f8af7e8"}

[commit-bot: I haz the power, 2017-08-04 23:31:11]

Description was changed from

==========
tokenserver: Boilerplate for loading and serving service_accounts.cfg.

It closely resembles handling of delegation.cfg config file. In particular,
it reuses most of the logic through policy.Policy class.

R=smut@google.com
BUG=731843
==========

to

==========
tokenserver: Boilerplate for loading and serving service_accounts.cfg.

It closely resembles handling of delegation.cfg config file. In particular,
it reuses most of the logic through policy.Policy class.

R=smut@google.com
BUG=731843

Review-Url: https://codereview.chromium.org/2993023002
Committed:
https://github.com/luci/luci-go/commit/944bd62ef8c6c11817b6cb7fccd1a84f5f8af7e8
==========

[commit-bot: I haz the power, 2017-08-04 23:31:12]

Committed patchset #3 (id:40001) as
https://github.com/luci/luci-go/commit/944bd62ef8c6c11817b6cb7fccd1a84f5f8af7e8

[smut, 2017-08-04 23:40:24]

https://codereview.chromium.org/2993023002/diff/40001/tokenserver/appengine/i...
File tokenserver/appengine/impl/serviceaccounts/config.go (right):

https://codereview.chromium.org/2993023002/diff/40001/tokenserver/appengine/i...
tokenserver/appengine/impl/serviceaccounts/config.go:101: func prepareRules(cfg
policy.ConfigBundle, revision string) (policy.Queryable, error) {
On 2017/08/04 23:25:29, Vadim Sh. wrote:
> On 2017/08/04 22:43:42, smut wrote:
> > Is a pointer to a Rules struct a type of policy.Queryable? I'm not sure I
see
> > how the declared return type matches what is being returned.
> 
> policy.Queryable is defined here:
>
https://github.com/luci/luci-go/blob/18ae6bdbc6652e10610d55e4528d4bb3c624f813...
> 
> Any thing that has 'ConfigRevision() string' method matches this interface.
> 
> *Rules does have 'ConfigRevision() string' method (it's defined on line 114),
> and thus it matches this interface.
> 
> Note that 'Rules{}' by itself (without '&') can't be cast to policy.Queryable,
> because the method is defined with the pointer as the receiver. Go doesn't
allow
> automatic type cast in this case: https://play.golang.org/p/MdP-wR1tNp (I
think
> because generally non-pointer values don't even guaranteed to have a stable
> address, though not sure).
> 
> It does allow the reverse though: methods with non-pointer receivers "apply"
to
> pointer entities: https://play.golang.org/p/yihRcb0YvZ (generally because Go
can
> always copy the value pointed by the pointer and pass it as the receiver).
> 
> Not the best explanation evar, I know...

Got it, thanks. I did't expect that interfaces would be implemented implicitly
like this.