From a15ac5a006c510e03303ef243005c415bfa9caf5 Mon Sep 17 00:00:00 2001
From: Deep Singhvi <deep@buildwithfern.com>
Date: Sun, 19 May 2024 10:05:08 -0400
Subject: [PATCH] (fix): improve local preview responsiveness (#3646)

---
 .pnp.cjs                                      |  2 -
 packages/cli/docs-preview/package.json        |  2 -
 .../cli/docs-preview/src/runPreviewServer.ts  | 63 ++++++++-----------
 yarn.lock                                     |  2 -
 4 files changed, 27 insertions(+), 42 deletions(-)

diff --git a/.pnp.cjs b/.pnp.cjs
index 0d63a1cbf59..249ade36bd6 100644
--- a/.pnp.cjs
+++ b/.pnp.cjs
@@ -6613,7 +6613,6 @@ function $$SETUP_STATE(hydrateRuntimeState, basePath) {
             ["@types/decompress", "npm:4.2.7"],\
             ["@types/express", "npm:4.17.20"],\
             ["@types/jest", "npm:29.0.3"],\
-            ["@types/lodash-es", "npm:4.17.12"],\
             ["@types/node", "npm:18.7.18"],\
             ["@types/uuid", "npm:9.0.8"],\
             ["@types/ws", "npm:8.5.10"],\
@@ -6625,7 +6624,6 @@ function $$SETUP_STATE(hydrateRuntimeState, basePath) {
             ["eslint", "npm:8.56.0"],\
             ["express", "npm:4.19.2"],\
             ["jest", "virtual:816fb67d993b0978271f762d4ccbec7209ef2546c234ca6e241662d44336c8e32c1c3c07189cfe14b67974a4840e1ed140408a7403bf9deb68c1953445072efe#npm:29.7.0"],\
-            ["lodash-es", "npm:4.17.21"],\
             ["organize-imports-cli", "npm:0.10.0"],\
             ["prettier", "npm:2.7.1"],\
             ["tmp-promise", "npm:3.0.3"],\
diff --git a/packages/cli/docs-preview/package.json b/packages/cli/docs-preview/package.json
index d5f3082bdf8..0aef1395da0 100644
--- a/packages/cli/docs-preview/package.json
+++ b/packages/cli/docs-preview/package.json
@@ -40,7 +40,6 @@
     "cors": "^2.8.5",
     "decompress": "^4.2.1",
     "express": "^4.19.2",
-    "lodash-es": "^4.17.21",
     "tmp-promise": "^3.0.3",
     "uuid": "^9.0.1",
     "watcher": "^2.3.1",
@@ -52,7 +51,6 @@
     "@types/decompress": "^4.2.7",
     "@types/express": "^4.17.20",
     "@types/jest": "^29.0.3",
-    "@types/lodash-es": "^4.17.12",
     "@types/node": "^18.7.18",
     "@types/uuid": "^9.0.8",
     "@types/ws": "^8.5.10",
diff --git a/packages/cli/docs-preview/src/runPreviewServer.ts b/packages/cli/docs-preview/src/runPreviewServer.ts
index 5796b3b3e81..e9056ebe280 100644
--- a/packages/cli/docs-preview/src/runPreviewServer.ts
+++ b/packages/cli/docs-preview/src/runPreviewServer.ts
@@ -7,7 +7,6 @@ import chalk from "chalk";
 import cors from "cors";
 import express from "express";
 import http from "http";
-import { debounce } from "lodash-es";
 import path from "path";
 import Watcher from "watcher";
 import { WebSocketServer, type WebSocket } from "ws";
@@ -52,54 +51,46 @@ export async function runPreviewServer({
         wrapWithHttps(initialProject.docsWorkspaces?.config.instances[0]?.url ?? "localhost:3000")
     );
 
-    let docsDefinition = getPreviewDocsDefinition({
+    let docsDefinition = await getPreviewDocsDefinition({
         domain: instance.host,
         project: initialProject,
         context
     });
 
-    const reloadDocsDefinition = debounce(
-        () => {
-            context.logger.info("Reloading project and docs");
-            const startTime = Date.now();
-            docsDefinition = reloadProject()
-                .then((project) => {
-                    context.logger.info(`Reload project took ${Date.now() - startTime}ms`);
-                    return getPreviewDocsDefinition({
-                        domain: instance.host,
-                        project,
-                        context
-                    });
-                })
-                .then((newDocsDefinition) => {
-                    context.logger.info(`Reload project and docs completed in ${Date.now() - startTime}ms`);
-                    return newDocsDefinition;
-                });
-            return docsDefinition;
-        },
-        300,
-        { leading: false, trailing: true }
-    );
+    const reloadDocsDefinition = async () => {
+        context.logger.info("Reloading project and docs");
+        const startTime = Date.now();
+        const project = await reloadProject();
+        context.logger.info(`Reload project took ${Date.now() - startTime}ms`);
+        const newDocsDefinition = await getPreviewDocsDefinition({
+            domain: instance.host,
+            project,
+            context
+        });
+        context.logger.info(`Reload project and docs completed in ${Date.now() - startTime}ms`);
+        return newDocsDefinition;
+    };
 
     const watcher = new Watcher(absoluteFilePathToFern, { recursive: true, ignoreInitial: true });
-    watcher.on("all", (event: string, targetPath: string, _targetPathNext: string) => {
+    watcher.on("all", async (event: string, targetPath: string, _targetPathNext: string) => {
         context.logger.debug(chalk.dim(`[${event}] ${targetPath}`));
-
         // after the docsDefinition is reloaded, send a message to all connected clients to reload the page
-        void reloadDocsDefinition()?.then(() => {
-            for (const connection of connections) {
-                connection.send(
-                    JSON.stringify({
-                        reload: true
-                    })
-                );
-            }
-        });
+        const reloadedDocsDefinition = await reloadDocsDefinition();
+        if (reloadedDocsDefinition != null) {
+            docsDefinition = reloadedDocsDefinition;
+        }
+        for (const connection of connections) {
+            connection.send(
+                JSON.stringify({
+                    reload: true
+                })
+            );
+        }
     });
 
     app.post("/v2/registry/docs/load-with-url", async (_, res) => {
         try {
-            const definition = await docsDefinition;
+            const definition = docsDefinition;
             const response: DocsV2Read.LoadDocsForUrlResponse = {
                 baseUrl: {
                     domain: instance.host,
diff --git a/yarn.lock b/yarn.lock
index e749c90b001..d976c60f205 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3569,7 +3569,6 @@ __metadata:
     "@types/decompress": ^4.2.7
     "@types/express": ^4.17.20
     "@types/jest": ^29.0.3
-    "@types/lodash-es": ^4.17.12
     "@types/node": ^18.7.18
     "@types/uuid": ^9.0.8
     "@types/ws": ^8.5.10
@@ -3581,7 +3580,6 @@ __metadata:
     eslint: ^8.56.0
     express: ^4.19.2
     jest: ^29.7.0
-    lodash-es: ^4.17.21
     organize-imports-cli: ^0.10.0
     prettier: ^2.7.1
     tmp-promise: ^3.0.3