move some implictly global state to env.js

lib/commands/metadata.js

@@ -2,7 +2,6 @@
 const Data = module.exports;
 
 const Meta = require("../metadata");
-const WriteQueue = require("../write-queue");
 const Core = require("./core");
 const Util = require("../common-util");
 const HK = require("../hk-util");
@@ -53,7 +52,6 @@ Data.getMetadata = function (Env, channel, cb, Server, netfluxId) {
         value: value
     }
 */
-var queueMetadata = WriteQueue();
 Data.setMetadata = function (Env, safeKey, data, cb, Server) {
     var unsafeKey = Util.unescapeKeyCharacters(safeKey);
 
@@ -63,7 +61,7 @@ Data.setMetadata = function (Env, safeKey, data, cb, Server) {
     if (!command || typeof (command) !== 'string') { return void cb('INVALID_COMMAND'); }
     if (Meta.commands.indexOf(command) === -1) { return void cb('UNSUPPORTED_COMMAND'); }
 
-    queueMetadata(channel, function (next) {
+    Env.queueMetadata(channel, function (next) {
         Data.getMetadataRaw(Env, channel, function (err, metadata) {
             if (err) {
                 cb(err);

lib/env.js

@@ -45,6 +45,7 @@ module.exports.create = function (config) {
         queueStorage: WriteQueue(),
         queueDeletes: WriteQueue(),
         queueValidation: WriteQueue(),
+        queueMetadata: WriteQueue(),
 
         batchIndexReads: BatchRead("HK_GET_INDEX"),
         batchMetadata: BatchRead('GET_METADATA'),