Cleanup host services (#195)

* Cleanup host services params handling
* Make the use of headers and non-enveloped message payloads consistent
across host services
* Make header names more self-documenting
* Move agent message header constants into agent api package
* Use Uint8Array in v8
* Use Bytes() when converting v8 bigint value
* Support objects, arrays, an strings when marshaling []byte from v8
value
* Use toUInt8ArrayValue() when passing payload into triggered v8 functions
* Only deal in native Uint8Array in v8 functions
* Make native v8 utility function name consistent
* Remove unused code
* Cleanup basic echofunction.js test

examples/v8/echofunction/src/echofunction.js

@@ -2,6 +2,6 @@
   console.log(subject);
   return {
     triggered_on: subject,
-    payload: payload
+    payload: String.fromCharCode(...payload)
   }
 };

examples/v8/echofunction/src/kv.js

@@ -5,6 +5,6 @@
   this.hostServices.kv.set('hello2', payload);
   return {
     keys: this.hostServices.kv.keys(),
-    hello2: this.hostServices.kv.get('hello2')
+    hello2: String.fromCharCode(...this.hostServices.kv.get('hello2'))
   }
 };

examples/v8/echofunction/src/messaging.js

@@ -1,28 +1,38 @@
 (subject, payload) => {
   this.hostServices.messaging.publish('hello.world', payload);
 
-  var req;
+  var reqResp;
   var reqEx;
 
-  var reqMany;
+  var reqManyResp;
   var reqManyEx;
 
   try {
-    req = this.hostServices.messaging.request('hello.world.request', payload);
+    reqResp = this.hostServices.messaging.request('hello.world.request', payload);
+    reqResp = String.fromCharCode(...reqResp)
   } catch (e) {
     reqEx = e;
   }
 
   try {
-    reqMany = this.hostServices.messaging.requestMany('hello.world.request.many', payload);
+    reqManyResp = []
+
+    let responses = this.hostServices.messaging.requestMany('hello.world.request.many', payload)
+
+    // responses is an array of Uint8Array... flatten it so we can use each value
+    responses = Array.prototype.slice.call(responses)
+
+    for (let i = 0; i < responses.length; i++) {
+      reqManyResp.push(String.fromCharCode(...responses[i]))
+    }
   } catch (e) {
     reqManyEx = e;
   }
 
   return {
-    'hello.world.request': req,
+    'hello.world.request': reqResp,
     'hello.world.request.ex': reqEx,
-    'hello.world.request.many': reqMany,
+    'hello.world.request.many': reqManyResp,
     'hello.world.request.many.ex': reqManyEx
   }
 };

examples/v8/echofunction/src/objectstore.js

@@ -5,6 +5,6 @@
   this.hostServices.objectStore.put('hello2', payload);
   return {
     list: this.hostServices.objectStore.list(),
-    hello2: this.hostServices.objectStore.get('hello2')
+    hello2: String.fromCharCode(...this.hostServices.objectStore.get('hello2'))
   }
 };

internal/agent-api/client.go

@@ -23,7 +23,16 @@ type EventCallback func(string, cloudevents.Event)
 type LogCallback func(string, LogEntry)
 
 const (
-	nexTriggerSubject = "x-nex-trigger-subject"
+	NexTriggerSubject = "x-nex-trigger-subject"
+	NexRuntimeNs      = "x-nex-runtime-ns"
+
+	HttpURLHeader = "x-http-url"
+
+	KeyValueKeyHeader = "x-keyvalue-key"
+
+	MessagingSubjectHeader = "x-subject"
+
+	ObjectStoreObjectNameHeader = "x-object-name"
 )
 
 type AgentClient struct {
@@ -182,7 +191,7 @@ func (a *AgentClient) UptimeMillis() time.Duration {
 func (a *AgentClient) RunTrigger(ctx context.Context, tracer trace.Tracer, subject string, data []byte) (*nats.Msg, error) {
 	intmsg := nats.NewMsg(fmt.Sprintf("agentint.%s.trigger", a.agentID))
 	// TODO: inject tracer context into message header
-	intmsg.Header.Add(nexTriggerSubject, subject)
+	intmsg.Header.Add(NexTriggerSubject, subject)
 	intmsg.Data = data
 
 	cctx, childSpan := tracer.Start(

internal/agent-api/types.go

@@ -169,12 +169,11 @@ type HostServicesHTTPResponse struct {
 	Error *string `json:"error,omitempty"`
 }
 
-type HostServicesKeyValueRequest struct {
-	Key   *string          `json:"key"`
-	Value *json.RawMessage `json:"value,omitempty"`
-
+type HostServicesKeyValueResponse struct {
 	Revision int64 `json:"revision,omitempty"`
 	Success  *bool `json:"success,omitempty"`
+
+	Errors []string `json:"errors,omitempty"`
 }
 
 type HostServicesObjectStoreResponse struct {