mesh app work. improve script setup

src/moto/client.js

@@ -0,0 +1,124 @@
+/** Copyright Stewart Allen <sa@grid.space> -- All Rights Reserved */
+
+"use strict";
+
+(function() {
+
+let MOTO = self.moto = self.moto || {},
+    time = function() { return new Date().getTime() },
+    restarting = false,
+    running = {},
+    workurl = null,
+    worker = null,
+    seqid = 1;
+
+/**
+ * @param {Function} fn name of function in MOTO.worker
+ * @param {Object} data to send to server
+ * @param {Function} onreply function to call on reply messages
+ * @param {Object[]} zerocopy array of objects to pass using zerocopy
+ */
+function send(fn, data, onreply, zerocopy) {
+    let seq = seqid++;
+
+    if (onreply) {
+        // establish listener and track replies
+        running[seq] = { fn:onreply };
+    }
+    let msg = {
+        seq: seq,
+        task: fn,
+        time: time(),
+        data: data
+    };
+    try {
+        worker.postMessage(msg, zerocopy);
+    } catch (error) {
+        console.trace('work send error', {data, error});
+    }
+}
+
+// code is running in the browser / client context
+let CLIENT = MOTO.client = {
+    send: send,
+
+    // factory can be overridden
+    newWorker: function(url = workurl) {
+        if (self.createWorker) {
+            return self.createWorker();
+        } else {
+            return new Worker(workurl = url);
+        }
+    },
+
+    // return number of running requests
+    current: function() {
+        let current = 0;
+        for (let rec of Object.values(running)) {
+            if (rec.fn) current++;
+        }
+        return current;
+    },
+
+    stop: function() {
+        if (worker) {
+            worker.terminate();
+            worker = null;
+        }
+    },
+
+    // same as restart
+    start: function(url) {
+        CLIENT.restart(url);
+    },
+
+    restart: function(url) {
+        // prevent re-entry from cancel callback
+        if (restarting) {
+            return;
+        }
+
+        CLIENT.stop();
+
+        restarting = true;
+
+        for (let key in running) {
+            let rec = running[key];
+            if (rec.fn) {
+                rec.fn({error: "cancelled operation"});
+            }
+        }
+
+        running = {};
+        worker = CLIENT.newWorker(url);
+
+        // bind to CLIENT to enable synth injections
+        CLIENT.onmessage = worker.onmessage = function(e) {
+            let now = time(),
+                reply = e.data,
+                record = running[reply.seq],
+                onreply = record ? record.fn : undefined;
+
+            if (reply.done) {
+                delete running[reply.seq];
+            }
+
+            // calculate and replace recv time
+            reply.time_recv = now - reply.time_recv;
+
+            if (onreply) {
+                onreply(reply.data, reply);
+            } else {
+                console.log({drop_reply: reply});
+            }
+        };
+
+        // signal worker client is ready
+        worker.postMessage("--init--");
+
+        restarting = false;
+    }
+
+};
+
+})();