Implement SDK SetLabel and SetAnnotation functionality

This implements new functions in the SDK:

- SetLabel(key, value) - that lets you set a label on the backing `GameServer`
- SetAnnotation(key, value) - that lets you set an annotation on the backing
`GameServer`

All keys are prefixed with "stable.agones.dev/sdk-" to maintain isolation.

Closes googleforgames#279

docs/sdk_rest_api.md

@@ -64,7 +64,9 @@ $ curl -d "{}" -H "Content-Type: application/json" -X POST http://localhost:5935
 
 ### Set Label
 
-TODO: write stuff here.
+Apply a Label with the prefix "stable.agones.dev/sdk-" to the backing `GameServer` metadata. 
+
+See the SDK [SetLabel](../sdks/README.md#setlabelkey-value) documentation for restrictions.
 
 #### Example
 
@@ -74,7 +76,7 @@ $ curl -d '{"key": "foo", "value": "bar"}' -H "Content-Type: application/json" -
 
 ### Set Annotation
 
-TODO: write stuff here.
+Apply a Annotation with the prefix "stable.agones.dev/sdk-" to the backing `GameServer` metadata
 
 #### Example
 

sdk.proto

@@ -56,8 +56,6 @@ service SDK {
     }
 
     // Apply a Label to the backing GameServer metadata
-    // TODO: document -- make note that keys and values are alpha, - .
-    // TODO: e2e test
     rpc SetLabel(KeyValue) returns (Empty) {
         option (google.api.http) = {
 			put: "/metadata/label"
@@ -66,8 +64,6 @@ service SDK {
     }
 
     // Apply a Annotation to the backing GameServer metadata
-    // TODO: document -- make note that keys are alpha, -, .
-    // TODO: e2e test
     rpc SetAnnotation(KeyValue) returns (Empty) {
         option (google.api.http) = {
 			put: "/metadata/annotation"

sdk.swagger.json

@@ -61,7 +61,7 @@
     },
     "/metadata/annotation": {
       "put": {
-        "summary": "Apply a Annotation to the backing GameServer metadata\nTODO: document",
+        "summary": "Apply a Annotation to the backing GameServer metadata",
         "operationId": "SetAnnotation",
         "responses": {
           "200": {
@@ -88,7 +88,7 @@
     },
     "/metadata/label": {
       "put": {
-        "summary": "Apply a Label to the backing GameServer metadata\nTODO: document",
+        "summary": "Apply a Label to the backing GameServer metadata",
         "operationId": "SetLabel",
         "responses": {
           "200": {

sdks/README.md

@@ -46,6 +46,24 @@ This tells Agones to shut down the currently running game server.
 The GameServer state will be set `Shutdown` and the 
 backing Pod will be deleted, if they have not shut themselves down already. 
 
+### SetLabel(key, value)
+⚠️⚠️⚠️ **`SetLabel` is currently a development feature and has not been released** ⚠️⚠️⚠️
+
+This will set a [Label](https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/) value on the backing `GameServer`
+record that is stored in Kubernetes. To maintain isolation, the `key` value is automatically prefixed with "stable.agones.dev/sdk-"
+
+> Note: There are limits on the characters that be used for label keys and values. Details are [here](https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#syntax-and-character-set).
+
+This can be useful if you want to information from your running game server process to be observable or searchable through the Kubernetes API.  
+
+### SetAnnotation(key, value)
+⚠️⚠️⚠️ **`SetAnnotation` is currently a development feature and has not been released** ⚠️⚠️⚠️
+
+This will set a [Annotation](https://kubernetes.io/docs/concepts/overview/working-with-objects/annotations/) value on the backing
+`Gameserver` record that is stored in Kubernetes. To maintain isolation, the `key` value is automatically prefixed with "stable.agones.dev/sdk-"
+
+This can be useful if you want to information from your running game server process to be observable through the Kubernetes API.
+
 ### GameServer()
 This returns most of the backing GameServer configuration and Status. This can be useful
 for instances where you may want to know Health check configuration, or the IP and Port
@@ -63,7 +81,7 @@ and the [examples](../examples).
 
 ### WatchGameServer(function(gameserver){...})
 
-⚠️⚠️⚠️ **`WatchGameServer` is currently a development feature and has not been released** ⚠️⚠️⚠
+⚠️⚠️⚠️ **`WatchGameServer` is currently a development feature and has not been released** ⚠️⚠️⚠️
 
 This executes the passed in callback with the current `GameServer` details whenever the underlying `GameServer` configuration is updated.
 This can be useful to track `GameServer > Status > State` changes, `metadata` changes, such as labels and annotations, and more.

sdks/cpp/README.md

@@ -50,14 +50,41 @@ if the function completed successfully.
 
 For more information you can also look at the [gRPC Status reference](https://grpc.io/grpc/cpp/classgrpc_1_1_status.html)
 
-
 ```cpp
 grpc::Status status = sdk->Shutdown();
 if (!status.ok()) { ... }
 ```
 
-For more information, you can also read the [SDK Overview](../), check out [sdk.h](sdk.h) and also look at the
-[C++ example](../../examples/cpp-simple).
+To [set a Label](../README.md#setlabelkey-value) on the backing `GameServer` call
+`sdk->SetLabel(key, value)`.
+
+⚠️⚠️⚠️ **`SetLabel` is currently a development feature and has not been released** ⚠️⚠️⚠️
+
+This will return a grpc::Status object, from which we can call `status.ok()` to determine
+if the function completed successfully.
+
+For more information you can also look at the [gRPC Status reference](https://grpc.io/grpc/cpp/classgrpc_1_1_status.html)
+
+```cpp
+grpc::Status status = sdk->SetLabel("test-label", "test-value");
+if (!status.ok()) { ... }
+```
+
+To [set an Annotation](../README.md#setannotationkey-value) on the backing `GameServer` call
+`sdk->SetAnnotation(key, value)`.
+
+⚠️⚠️⚠️ **`SetAnnotation` is currently a development feature and has not been released** ⚠️⚠️⚠️
+
+This will return a grpc::Status object, from which we can call `status.ok()` to determine
+if the function completed successfully.
+
+For more information you can also look at the [gRPC Status reference](https://grpc.io/grpc/cpp/classgrpc_1_1_status.html)
+
+```cpp
+status = sdk->SetAnnotation("test-annotation", "test value");
+if (!status.ok()) { ... }
+```
+
 
 To get the details on the [backing `GameServer`](../README.md#gameserver) call `sdk->GameServer(&gameserver)`,
 passing in a `stable::agones::dev::sdk::GameServer*` to push the results of the `GameServer` configuration into.
@@ -71,10 +98,7 @@ grpc::Status status = sdk->GameServer(&gameserver);
 if (!status.ok()) {...}
 ```
 
-For more information, you can also read the [SDK Overview](../), check out [sdk.h](sdk.h) and also look at the
-[C++ example](../../examples/cpp-simple).
-
-To get updates on the [backing `GameServer`](../README.md#gameserver) as they happen, 
+To get [updates on the backing `GameServer`](../README.md#watchgameserverfunctiongameserver) as they happen, 
 call `sdk->WatchGameServer([](stable::agones::dev::sdk::GameServer gameserver){...})`.
 
 ⚠️⚠️⚠️ **`WatchGameServer` is currently a development feature and has not been released** ⚠️⚠️️⚠️ 

sdks/cpp/sdk.h

@@ -42,10 +42,12 @@ namespace agones {
             // Marks the Game Server as ready to shutdown
             grpc::Status Shutdown();
 
-            // Set a label on the current GameServer
+            // SetLabel sets a metadata label on the `GameServer` with the prefix
+            // stable.agones.dev/sdk-
             grpc::Status SetLabel(std::string key, std::string value);
 
-            // Set an Annotation on the current GameServer
+            // SetAnnotation sets a metadata annotation on the `GameServer` with the prefix
+            // stable.agones.dev/sdk-
             grpc::Status SetAnnotation(std::string key, std::string value);
 
             // Watch the GameServer configuration, and fire the callback