fixes #807 - changes map for grpc connections to be a string key

[nathanejohnson]

This should be a more complete fix for #807 , inspired by #808

[nathanejohnson]

@qqwx1986 @cmvoicu can you take a look at this PR and see if this addresses your issue?

[qqwx1986]

@qqwx1986 @cmvoicu can you take a look at this PR and see if this addresses your issue?

thanks, it's addresses the second problem. i need wait finish processing grpc requests although this target are uninstalled but not disconnected

if !hasTarget(tKey, table) {
   if cs.GetState() != connectivity.Ready {  // it will make sure finished all processing grpc requests  before remove
        log.Println("[DEBUG] grpc: cleaning up connection to", tKey)
        cs.Close()
        delete(p.connections, tKey)
   }
}

[Vetrenik]

Is there some progress with merging this pull request?

[yuriy-yarosh]

Yup, we need this...

[aaronhurt]

We're just waiting on confirmation from @qqwx1986. If someone else in a similar situation could test and confirm that would be appreciated.

[qqwx1986]

We're just waiting on confirmation from @qqwx1986. If someone else in a similar situation could test and confirm that would be appreciated.

i think this pr just fix one problem, and another i had reply up floor