router: support random value for cluster specifier plugin

[wbpcode]

Commit Message: router: support random value for cluster specifier plugin
Additional Description:

Now, the cluster specifier plugin could also use the random value to select cluster.

Risk Level: low.
Testing: n/a.
Docs Changes: n/a.
Release Notes: n/a.
Platform Specific Features:
[Optional Runtime guard:]
[Optional Fixes #Issue]
[Optional Fixes commit #PR or SHA]
[Optional Deprecated:]
[Optional API Considerations:]

[wbpcode]

/retest

[wbpcode]

Hi, @agrawroh, could you take a quick look at this when you get free time. I think you have reviewed lots of related changes. So, nag you again here. 🙏

[ramaraochavali]

Curious, where is this random value used now and what is the use case? I just seeing the interface change but none of the implementations use it

[wbpcode]

Curious, where is this random value used now and what is the use case? I just seeing the interface change but none of the implementations use it

I will wrap the weighted cluster as an cluster specifier plugin at next PR and the random value will be used there. It will also be helpful for any custom specifier plugin where need a consitant random value as reference of cluster selection.

[agrawroh]

LGTM, Thank You @wbpcode!

Should we add a test for the new behavior or would it be part of the follow-up?

[agrawroh]

Curious, where is this random value used now and what is the use case? I just seeing the interface change but none of the implementations use it

I will wrap the weighted cluster as an cluster specifier plugin at next PR and the random value will be used there. It will also be helpful for any custom specifier plugin where need a consitant random value as reference of cluster selection.

Sorry for the delay, didn't get enough time on Friday.

[wbpcode]

LGTM, Thank You @wbpcode!

Should we add a test for the new behavior or would it be part of the follow-up?

I should be covered by the weighted cluster PR.

[wbpcode]

/assign-from @envoyproxy/senior-maintainers ping for an approval from senior maintainer for the core code change.

[repokitteh-read-only]

@envoyproxy/senior-maintainers assignee is @yanavlasov
ping assignee is @None
for assignee is @None
an assignee is @None
approval assignee is @None
from assignee is @None
senior assignee is @None
maintainer assignee is @None
for assignee is @None
the assignee is @None
core assignee is @None
code assignee is @None
change. assignee is @None

🐱

Caused by: a #39979 (comment) was created by @wbpcode.

see: more, trace.