Add Deluge widget

- Create semi-generic jsonrpc proxy handler
- Refactor NZBGet to use jsonrpc proxy handler

closes #190

src/widgets/deluge/proxy.js

@@ -0,0 +1,63 @@
+import { formatApiCall } from "utils/proxy/api-helpers";
+import { sendJsonRpcRequest } from "utils/proxy/handlers/jsonrpc";
+import getServiceWidget from "utils/config/service-helpers";
+import createLogger from "utils/logger";
+import widgets from "widgets/widgets";
+
+const logger = createLogger("delugeProxyHandler");
+
+const dataMethod = "web.update_ui";
+const dataParams = [
+  ["queue", "name", "total_wanted", "state", "progress", "download_payload_rate", "upload_payload_rate", "total_remaining"],
+  {}
+];
+const loginMethod = "auth.login";
+
+async function sendRpc(url, method, params, username, password) {
+  const [status, contentType, data] = await sendJsonRpcRequest(url, method, params, username, password);
+  const json = JSON.parse(data.toString());
+  if (json?.error) {
+    if (json.error.code === 1) {
+      return [403, contentType, data];
+    }
+    return [500, contentType, data];
+  }
+
+  return [status, contentType, data];
+}
+
+function login(url, username, password) {
+  return sendRpc(url, loginMethod, [password], username, password);
+}
+
+export default async function delugeProxyHandler(req, res) {
+  const { group, service } = req.query;
+
+  if (!group || !service) {
+    logger.debug("Invalid or missing service '%s' or group '%s'", service, group);
+    return res.status(400).json({ error: "Invalid proxy service type" });
+  }
+
+  const widget = await getServiceWidget(group, service);
+
+  if (!widget) {
+    logger.debug("Invalid or missing widget for service '%s' in group '%s'", service, group);
+    return res.status(400).json({ error: "Invalid proxy service type" });
+  }
+
+  const api = widgets?.[widget.type]?.api
+  const url = new URL(formatApiCall(api, { ...widget }));
+
+  let [status, contentType, data] = await sendRpc(url, dataMethod, dataParams, widget.username, widget.password);
+  if (status === 403) {
+    [status, contentType, data] = await login(url, widget.username, widget.password);
+    if (status !== 200) {
+      return res.status(status).end(data);
+    }
+
+    // eslint-disable-next-line no-unused-vars
+    [status, contentType, data] = await sendRpc(url, dataMethod, dataParams, widget.username, widget.password);
+  }
+
+  return res.status(status).end(data);
+}