Include service parameters and spec in manifest and state meta.

This upstreams functionality used in the ACO and RaceResults.ru clients
(and should be common to all services that use the parameter
functionality).

Author: jamesremuscat

src/services/services.js

@@ -80,13 +80,21 @@ export class Service extends EventEmitter {
     newState.lastUpdated = Date.now();
     delete newState.extraMessages;
 
+    if (this.parameters && this.constructor.parametersSpec) {
+      if (!newState.meta) {
+        newState.meta = {};
+      }
+      newState.meta.parameters = this.parameters;
+    }
+
     this.emit(Events.STATE_CHANGE, newState);
     this._prevState = newState;
   }
 
   /**
-   * Adds start time and UUID to the manifest, and if a deep equality check
-   * fails, emits an event with the new manifest then updates our state.
+   * Adds start time, UUID and parameters (if appropriate) to the manifest, and
+   * if a deep equality check fails, emits an event with the new manifest then
+   * updates our state.
    */
   onManifestChange(newManifest) {
     const newManifestWithStartTime = {
@@ -95,6 +103,10 @@ export class Service extends EventEmitter {
       uuid: this.service.uuid
     };
 
+    if (this.constructor.parametersSpec) {
+      newManifestWithStartTime.parameters = this.constructor.parametersSpec;
+    }
+
     if (!deepEqual(newManifestWithStartTime, this._prevState.manifest)) {
       this.emit(Events.MANIFEST_CHANGE, newManifestWithStartTime);
       this.onStateChange({ manifest: newManifestWithStartTime });