chainInfo from server, routes, wallet rework

src/misc.js

@@ -0,0 +1,35 @@
+
+export class SingletonCoroutine {
+    constructor(f, delay=10, retry=true) {
+        this.f = f
+        this.delay = delay
+        this.timeout = null
+        this.args = null
+    }
+
+    pending() {
+        return this.timeout !== null
+    }
+
+    invoke(/*arguments*/) {
+        this.args = arguments
+        if( this.timeout !== null )
+            clearTimeout(this.timeout)
+        this.timeout = setTimeout(this.onTimeout, this.delay, this)
+    }
+
+    async onTimeout(self) {
+        self.timeout = null
+        console.log('invoking', self.f, self.args)
+        try {
+            await self.f(...self.args)
+        }
+        catch (e) {
+            if( self.retry )
+                self.invoke(self.args)
+            else
+                console.error(e)
+        }
+    }
+
+}