* added method for converting SamenessGroupConfigEntry
- added new method `ToQueryFailoverTargets` for converting a SamenessGroupConfigEntry's members to a list of QueryFailoverTargets
- renamed `ToFailoverTargets` ToServiceResolverFailoverTargets to distinguish it from `ToQueryFailoverTargets`
* Added SamenessGroup to PreparedQuery
- exposed Service.Partition to API when defining a prepared query
- added a method for determining if a QueryFailoverOptions is empty
- This will be useful for validation
- added unit tests
* added method for retrieving a SamenessGroup to state store
* added logic for using PQ with SamenessGroup
- added branching path for SamenessGroup handling in execute. It will be handled separate from the normal PQ case
- added a new interface so that the `GetSamenessGroupFailoverTargets` can be properly tested
- separated the execute logic into a `targetSelector` function so that it can be used for both failover and sameness group PQs
- split OSS only methods into new PQ OSS files
- added validation that `samenessGroup` is an enterprise only feature
* added documentation for PQ SamenessGroup
Given a query like:
```
{
"Name": "tagged-connect-query",
"Service": {
"Service": "foo",
"Tags": ["tag"],
"Connect": true
}
}
```
And a Consul configuration like:
```
{
"services": [
"name": "foo",
"port": 8080,
"connect": { "sidecar_service": {} },
"tags": ["tag"]
]
}
```
If you executed the query it would always turn up with 0 results. This was because the sidecar service was being created without any tags. You could instead make your config look like:
```
{
"services": [
"name": "foo",
"port": 8080,
"connect": { "sidecar_service": {
"tags": ["tag"]
} },
"tags": ["tag"]
]
}
```
However that is a bit redundant for most cases. This PR ensures that the tags and service meta of the parent service get copied to the sidecar service. If there are any tags or service meta set in the sidecar service definition then this copying does not take place. After the changes, the query will now return the expected results.
A second change was made to prepared queries in this PR which is to allow filtering on ServiceMeta just like we allow for filtering on NodeMeta.
* Add cache types for catalog/services and health/services and basic test that caching works
* Support non-blocking cache types with Cache-Control semantics.
* Update API docs to include caching info for every endpoint.
* Comment updates per PR feedback.
* Add note on caching to the 10,000 foot view on the architecture page to make the new data path more clear.
* Document prepared query staleness quirk and force all background requests to AllowStale so we can spread service discovery load across servers.