Add tags to invokers.

[style95]

Description

This is to enable tag-based scheduling.
We can add tags to invokers like below.

[invokers]
invoker0            ansible_host=172.17.0.1 ansible_connection=local tags="['v2', 'gpu']"

There are already some codes for tag-based scheduling.
https://github.com/apache/openwhisk/blob/master/tests/src/test/scala/org/apache/openwhisk/core/scheduler/container/test/ContainerManagerTests.scala#L615

This is to add missing parts.

Related issue and scope

• I opened an issue to propose and discuss this change (#????)

My changes affect the following components

• API
• Controller
• Message Bus (e.g., Kafka)
• Loadbalancer
• Scheduler
• Invoker
• Intrinsic actions (e.g., sequences, conductors)
• Data stores (e.g., CouchDB)
• Tests
• Deployment
• CLI
• General tooling
• Documentation

Types of changes

• Bug fix (generally a non-breaking change which closes an issue).
• Enhancement or new feature (adds new functionality).
• Breaking change (a bug fix or enhancement which changes existing behavior).

Checklist:

• I signed an Apache CLA.
• I reviewed the style guides and followed the recommendations (Travis CI will check :).
• I added tests to cover my changes.
• My changes require further changes to the documentation.
• I updated the documentation where necessary.

[ningyougang]

• Can add some example of how to user it? e.g. If my action wants to use special invokers(e.g. include TAG: cpu in ansible), my action should meet what condition?
• Can use in kubernetes?

[ningyougang]

LGTM with some small questions.

[codecov-commenter]

Codecov Report

Merging #5289 (3f6efcb) into master (a03507c) will decrease coverage by 4.67%.
The diff coverage is 91.66%.

@@            Coverage Diff             @@
##           master    #5289      +/-   ##
==========================================
- Coverage   79.90%   75.23%   -4.68%     
==========================================
  Files         238      238              
  Lines       14161    14172      +11     
  Branches      603      624      +21     
==========================================
- Hits        11316    10662     -654     
- Misses       2845     3510     +665     

Impacted Files	Coverage Δ
...la/org/apache/openwhisk/core/invoker/Invoker.scala	73.33% <90.90%> (+2.56%)	⬆️
.../scala/org/apache/openwhisk/core/WhiskConfig.scala	95.97% <100.00%> (+0.02%)	⬆️
...core/database/cosmosdb/RxObservableImplicits.scala	0.00% <0.00%> (-100.00%)	⬇️
...ore/database/cosmosdb/cache/CacheInvalidator.scala	0.00% <0.00%> (-100.00%)	⬇️
...e/database/cosmosdb/cache/ChangeFeedConsumer.scala	0.00% <0.00%> (-100.00%)	⬇️
...core/database/cosmosdb/CosmosDBArtifactStore.scala	0.00% <0.00%> (-95.85%)	⬇️
...sk/core/database/cosmosdb/CosmosDBViewMapper.scala	0.00% <0.00%> (-93.90%)	⬇️
...tabase/cosmosdb/cache/CacheInvalidatorConfig.scala	0.00% <0.00%> (-92.31%)	⬇️
...enwhisk/connector/kafka/KamonMetricsReporter.scala	0.00% <0.00%> (-83.34%)	⬇️
...e/database/cosmosdb/cache/KafkaEventProducer.scala	0.00% <0.00%> (-78.58%)	⬇️
... and 16 more

[style95]

I confirmed it's working as expected.
I wl add documentation about this as well.

OW operators can configure tags for invokers like this.

invoker0 ansible_host=${INVOKER0} tags="['v1', 'gpu']"
invoker1 ansible_host=${INVOKER1} tags="['v1', 'cpu']"
invoker2 ansible_host=${INVOKER2} tags="['v2', 'gpu']"
invoker3 ansible_host=${INVOKER3} tags="['v2', 'cpu']"
invoker4 ansible_host=${INVOKER4} tags="['v1', 'mem']"
invoker5 ansible_host=${INVOKER5} tags="['v2', 'mem']"
invoker6 ansible_host=${INVOKER6} tags="['v2']"
invoker7 ansible_host=${INVOKER7} tags="['v2']"
invoker8 ansible_host=${INVOKER8}
invoker9 ansible_host=${INVOKER9}

Users can add the following annotations to their actions.

wsk action update params tests/dat/actions/params.js -i -a invoker-resources '["v2", "gpu"]'

Activation for this action will be delivered to invoker2.

The annotations and the corresponding target invokers are as follows.

• ["v1", "gpu"] -> invoker0
• ["v2", "gpu"] -> invoker2
• ["v1", "cpu"] -> invoker1
• ["v2"] -> One of invoker2, invoker3, invoker5, invoker6, and invoker7
• ["v1"] -> One of invoker0, invoker1, invoker4
• No annotation -> One of invoker8 and invoker9 is chosen first. if they have no resource, choose one of the invokers with tags.

[style95]

It looks like this.

[2022-07-21T11:00:02.599Z] [INFO] [#tid_sid_unknown] [Invoker] invoker tags: (v1, cpu)

[style95]

It is required for the subsequent change.
Let me merge this for now.
Please feel free to leave any comments. I would apply them in the subsequent PR if anyone has.