Sidecar Placement Address should be optional

[badgeratu]

Expected Behavior

The --placement-host-address parameter should not be passed to the Dapr Sidecar by default unless specifically instructed.

Actual Behavior

As of Dapr 1.2 when the CLI dapr.exe launches daprd.exe it adds a default placement service address:

daprd ... --placement-host-address 127.0.0.1:6050 ...

Normally placement would be running in a local development environment in a container exposing that port (or 50005 on non-Windows) but if a service doesn't need placement/actor support it should be possible to disable this as at present the sidecar continually gives DBG log warnings about being unable to connect:

12:12:16.857 [DBG] [Man.Dapr.Sidekick.DaprSidecarHost]  try to connect to placement service: 127.0.0.1:6050
12:12:16.862 [DBG] [Man.Dapr.Sidekick.DaprSidecarHost]  error connecting to placement service: rpc error: code = Unavailable desc = connection error: desc = "transport: authentication handshake failed: tls: first record does not look like a TLS handshake"

As Sidekick is invoking daprd.exe directly, it would be useful if Sidekick had a configuration option to override this so it could prevent the --placement-host-address being specified entirely, which would result in a single warning-level log message on startup which might be preferable:

time="2021-06-02T12:48:36.2391259+01:00" level=warning msg="failed to init actors: actors: couldn't connect to placement service: address is empty" app_id=dapr-gateway instance=LONL20439 scope=dapr.runtime type=log ver=1.2.0

Note also that setting the existing DaprSidecarOptions.PlacementHostAdress to an empty string does not currently prevent the default address being passed to daprd.exe.

Steps to Reproduce the Problem

1. Make sure Dapr is fully initialized locally (i.e. dapr init)
2. Add Dapr Sidekick to a new ASP.NET Core Web API project
3. Set the default Microsoft log level to Debug
4. Make sure the default placement service container is not running
5. Run the project in Console mode - the log messages above will be displayed.

RELEASE NOTE:

FIX: Do not assign a default placement-host-address to Sidecar

[badgeratu]

Actually I don't think we will need this. The warning log messages are currently just DBG level, and the check for local placement service is very fast so doesn't seem to have any impact.

[badgeratu]

This does actually cause a problem with Dapr 1.3 when Sidekick is tarted the same host that a placement service is running as a member of a multi-node cluster, and that node is not the elected leader. Therefore we do need to be able to optionally disable it.