- A new endpoint `/v1/agent/service/:service_id` which is a generic way to look up the service for a single instance. The primary value here is that it:
- **supports hash-based blocking** and so;
- **replaces `/agent/connect/proxy/:proxy_id`** as the mechanism the built-in proxy uses to read its config.
- It's not proxy specific and so works for any service.
- It has a temporary shim to call through to the existing endpoint to preserve current managed proxy config defaulting behaviour until that is removed entirely (tested).
- The built-in proxy now uses the new endpoint exclusively for it's config
- The built-in proxy now has a `-sidecar-for` flag that allows the service ID of the _target_ service to be specified, on the condition that there is exactly one "sidecar" proxy (that is one that has `Proxy.DestinationServiceID` set) for the service registered.
- Several fixes for edge cases for SidecarService
- A fix for `Alias` checks - when running locally they didn't update their state until some external thing updated the target. If the target service has no checks registered as below, then the alias never made it past critical.
Cosmetic fix to the agent's HTTP check function which always formats the result as "HTTP GET ...", ignoring any non-GET supplied HTTP method such as POST, PUT, etc.
There were places where we still didn't have the script vs. args sorted
correctly so changed all the logging to be just based on check IDs and
also made everything uniform.
Also removed some annoying debug logging, and moved some of the large output
logging to TRACE level.
Closes#3602
The Docker agent closes the connection during read after we have
read the body. This causes a "connection reset by peer" even though
the command was successful.
We ignore that error here since we got the correct status code
and a response body.
