add simple-host example
This commit is contained in:
Olivier Chafik
parent
535dae6a73
commit
1f3bc52142
5 changed files with 1187 additions and 13 deletions
115
examples/simple-host/src/app-host-utils.ts
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115
examples/simple-host/src/app-host-utils.ts
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import { McpUiSandboxProxyReadyNotificationSchema } from "@modelcontextprotocol/ext-apps";
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import { Client } from "@modelcontextprotocol/sdk/client/index.js";
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import { Tool } from "@modelcontextprotocol/sdk/types.js";
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const MCP_UI_RESOURCE_META_KEY = "ui/resourceUri";
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export async function setupSandboxProxyIframe(sandboxProxyUrl: URL): Promise<{
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iframe: HTMLIFrameElement;
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onReady: Promise<void>;
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}> {
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const iframe = document.createElement("iframe");
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iframe.style.width = "100%";
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iframe.style.height = "600px";
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iframe.style.border = "none";
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iframe.style.backgroundColor = "transparent";
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// iframe.allow = 'microphone'
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iframe.setAttribute("sandbox", "allow-scripts allow-same-origin allow-forms");
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const onReady = new Promise<void>((resolve, _reject) => {
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const initialListener = async (event: MessageEvent) => {
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if (event.source === iframe.contentWindow) {
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if (
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event.data &&
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event.data.method ===
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McpUiSandboxProxyReadyNotificationSchema.shape.method._def.value
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) {
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window.removeEventListener("message", initialListener);
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resolve();
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}
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}
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};
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window.addEventListener("message", initialListener);
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});
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iframe.src = sandboxProxyUrl.href;
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return { iframe, onReady };
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}
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export type ToolUiResourceInfo = {
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uri: string;
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};
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export async function getToolUiResourceUri(
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client: Client,
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toolName: string,
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): Promise<ToolUiResourceInfo | null> {
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let tool: Tool | undefined;
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let cursor: string | undefined = undefined;
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do {
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const toolsResult = await client.listTools({ cursor });
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tool = toolsResult.tools.find((t) => t.name === toolName);
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cursor = toolsResult.nextCursor;
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} while (!tool && cursor);
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if (!tool) {
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throw new Error(`tool ${toolName} not found`);
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}
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if (!tool._meta) {
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return null;
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}
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let uri: string;
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if (MCP_UI_RESOURCE_META_KEY in tool._meta) {
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uri = String(tool._meta[MCP_UI_RESOURCE_META_KEY]);
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} else {
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return null;
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}
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if (!uri.startsWith("ui://")) {
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throw new Error(
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`tool ${toolName} has unsupported output template URI: ${uri}`,
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);
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}
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return { uri };
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}
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export async function readToolUiResourceHtml(
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client: Client,
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opts: {
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uri: string;
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},
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): Promise<string> {
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const resource = await client.readResource({ uri: opts.uri });
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if (!resource) {
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throw new Error("UI resource not found: " + opts.uri);
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}
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if (resource.contents.length !== 1) {
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throw new Error(
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"Unsupported UI resource content length: " + resource.contents.length,
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);
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}
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const content = resource.contents[0];
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let html: string;
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const isHtml = (t?: string) => t === "text/html+mcp";
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if (
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"text" in content &&
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typeof content.text === "string" &&
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isHtml(content.mimeType)
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) {
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html = content.text;
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} else if (
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"blob" in content &&
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typeof content.blob === "string" &&
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isHtml(content.mimeType)
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) {
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html = atob(content.blob);
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} else {
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throw new Error(
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"Unsupported UI resource content format: " + JSON.stringify(content),
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);
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}
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return html;
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}
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253
examples/simple-host/src/example-host-react.tsx
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253
examples/simple-host/src/example-host-react.tsx
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import { Client } from "@modelcontextprotocol/sdk/client/index.js";
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import { SSEClientTransport } from "@modelcontextprotocol/sdk/client/sse.js";
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import { StreamableHTTPClientTransport } from "@modelcontextprotocol/sdk/client/streamableHttp.js";
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import { Tool } from "@modelcontextprotocol/sdk/types.js";
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import { useEffect, useState } from "react";
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import { createRoot } from "react-dom/client";
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import { UIActionResult } from "../src/mcp-ui-types.js";
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import { UITemplatedToolCallRenderer } from "../src/react/UITemplatedToolCallRenderer.js";
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const SANDBOX_PROXY_URL = URL.parse("/sandbox.html", location.href);
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/**
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* Example React application demonstrating the UITemplatedToolCallRenderer component.
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*
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* This shows how to:
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* - Connect to an MCP server
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* - List available tools
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* - Render tool UIs using UITemplatedToolCallRenderer
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* - Handle UI actions from the tool
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*/
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function ExampleApp() {
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const [client, setClient] = useState<Client | null>(null);
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const [tools, setTools] = useState<Tool[]>([]);
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const [activeTools, setActiveTools] = useState<
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Array<{ id: string; name: string; input: Record<string, unknown> }>
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>([]);
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const [error, setError] = useState<string | null>(null);
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// Connect to MCP server on mount
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useEffect(() => {
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let mounted = true;
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async function connect() {
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try {
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const newClient = new Client({
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name: "MCP UI React Host",
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version: "1.0.0",
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});
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const mcpServerUrl = new URL("http://localhost:3001/mcp");
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console.log(
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"[React Host] Attempting SSE connection to",
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mcpServerUrl.href,
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);
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try {
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await newClient.connect(new SSEClientTransport(mcpServerUrl));
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console.log("[React Host] SSE connection successful");
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} catch (err) {
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console.warn(
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"[React Host] SSE connection failed, falling back to HTTP:",
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err,
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);
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await newClient.connect(
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new StreamableHTTPClientTransport(mcpServerUrl),
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);
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console.log("[React Host] HTTP connection successful");
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}
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if (!mounted) return;
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// List available tools
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const toolsResult = await newClient.listTools();
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if (!mounted) return;
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setClient(newClient);
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setTools(toolsResult.tools);
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} catch (err) {
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if (!mounted) return;
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const errorMsg = err instanceof Error ? err.message : String(err);
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setError(`Failed to connect to MCP server: ${errorMsg}`);
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console.error("[React Host] Connection error:", err);
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}
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}
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connect();
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return () => {
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mounted = false;
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};
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}, []);
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const handleAddToolUI = (
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toolName: string,
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input: Record<string, unknown>,
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) => {
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const id = `${toolName}-${Date.now()}`;
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setActiveTools((prev) => [...prev, { id, name: toolName, input }]);
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};
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const handleRemoveToolUI = (id: string) => {
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setActiveTools((prev) => prev.filter((t) => t.id !== id));
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};
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const handleUIAction = async (toolId: string, action: UIActionResult) => {
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console.log(`[React Host] UI Action from ${toolId}:`, action);
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if (action.type === "intent") {
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console.log(
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"[React Host] Intent:",
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action.payload.intent,
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action.payload.params,
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);
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} else if (action.type === "link") {
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console.log("[React Host] Opening link:", action.payload.url);
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window.open(action.payload.url, "_blank", "noopener,noreferrer");
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} else if (action.type === "prompt") {
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console.log("[React Host] Prompt:", action.payload.prompt);
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} else if (action.type === "notify") {
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console.log("[React Host] Notification:", action.payload.message);
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}
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};
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const handleError = (toolId: string, err: Error) => {
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console.error(`[React Host] Error from tool ${toolId}:`, err);
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setError(`Tool ${toolId}: ${err.message}`);
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};
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if (error) {
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return (
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<div style={{ padding: "20px" }}>
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<h1>Example MCP-UI React Host</h1>
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<div
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style={{
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color: "red",
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padding: "10px",
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border: "1px solid red",
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borderRadius: "4px",
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}}
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>
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<strong>Error:</strong> {error}
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</div>
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<button onClick={() => window.location.reload()}>Retry</button>
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</div>
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);
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}
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if (!client) {
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return (
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<div style={{ padding: "20px" }}>
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<h1>Example MCP-UI React Host</h1>
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<p>Connecting to MCP server...</p>
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</div>
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);
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}
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return (
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<div style={{ padding: "20px", fontFamily: "system-ui, sans-serif" }}>
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<h1>Example MCP-UI React Host</h1>
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<div
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style={{
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marginBottom: "20px",
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padding: "15px",
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backgroundColor: "#f5f5f5",
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borderRadius: "4px",
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}}
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>
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<h2 style={{ marginTop: 0 }}>Available Tools</h2>
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{tools.length === 0 ? (
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<p>No tools available with UI resources.</p>
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) : (
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<div style={{ display: "flex", gap: "10px", flexWrap: "wrap" }}>
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{tools.map((tool) => (
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<button
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key={tool.name}
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onClick={() => {
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// Example input - in a real app, you'd have a form for this
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const input = tool.name.startsWith("pizza-")
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? { pizzaTopping: "Mushrooms" }
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: { message: "Hello from React!" };
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handleAddToolUI(tool.name, input);
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}}
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style={{
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padding: "8px 16px",
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backgroundColor: "#007bff",
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color: "white",
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border: "none",
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borderRadius: "4px",
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cursor: "pointer",
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}}
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>
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Add {tool.name}
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</button>
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))}
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</div>
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)}
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</div>
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<div style={{ display: "flex", flexDirection: "column", gap: "20px" }}>
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{activeTools.map((tool) => (
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<div
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key={tool.id}
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style={{
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padding: "10px",
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border: "2px solid #ddd",
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borderRadius: "8px",
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position: "relative",
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}}
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>
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<div
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style={{
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display: "flex",
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justifyContent: "space-between",
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alignItems: "center",
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marginBottom: "10px",
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}}
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>
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<h3 style={{ margin: 0 }}>{tool.name}</h3>
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<button
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onClick={() => handleRemoveToolUI(tool.id)}
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style={{
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padding: "4px 12px",
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backgroundColor: "#dc3545",
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color: "white",
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border: "none",
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borderRadius: "4px",
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cursor: "pointer",
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}}
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>
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Remove
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</button>
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</div>
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<UITemplatedToolCallRenderer
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sandboxProxyUrl={SANDBOX_PROXY_URL}
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client={client}
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toolName={tool.name}
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toolInput={tool.input}
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onUIAction={(action) => handleUIAction(tool.id, action)}
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onError={(err) => handleError(tool.id, err)}
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/>
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</div>
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))}
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{activeTools.length === 0 && (
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<p style={{ color: "#666", textAlign: "center", padding: "40px" }}>
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No tool UIs active. Click a button above to add one.
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</p>
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)}
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</div>
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</div>
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);
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}
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// Mount the React app
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const root = document.getElementById("root");
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if (root) {
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createRoot(root).render(<ExampleApp />);
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} else {
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console.error("Root element not found");
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}
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166
examples/simple-host/src/example-host.ts
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166
examples/simple-host/src/example-host.ts
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import {
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AppBridge,
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PostMessageTransport,
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} from "@modelcontextprotocol/ext-apps/app-bridge";
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import {
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setupSandboxProxyIframe,
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getToolUiResourceUri,
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readToolUiResourceHtml,
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} from "../src/app-host-utils";
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import { Client } from "@modelcontextprotocol/sdk/client/index.js";
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import { StreamableHTTPClientTransport } from "@modelcontextprotocol/sdk/client/streamableHttp.js";
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import { SSEClientTransport } from "@modelcontextprotocol/sdk/client/sse.js";
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import { LoggingMessageNotificationSchema } from "@modelcontextprotocol/sdk/types.js";
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import {
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McpUiOpenLinkRequestSchema,
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McpUiMessageRequestSchema,
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McpUiSizeChangeNotificationSchema,
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} from "@modelcontextprotocol/ext-apps";
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const SANDBOX_PROXY_URL = URL.parse("/sandbox.html", location.href)!;
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window.addEventListener("load", async () => {
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const client = new Client({
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name: "MCP UI Proxy Server",
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version: "1.0.0",
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});
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const mcpServerUrl = new URL("http://localhost:3001/mcp");
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console.log("[Client] Attempting SSE connection to", mcpServerUrl.href);
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try {
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await client.connect(new SSEClientTransport(mcpServerUrl));
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console.log("[Client] SSE connection successful");
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} catch (error) {
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console.warn(
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"[Client] SSE connection failed, falling back to HTTP:",
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error,
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);
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await client.connect(new StreamableHTTPClientTransport(mcpServerUrl));
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console.log("[Client] HTTP connection successful");
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}
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const tools = Object.fromEntries(
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(await client.listTools()).tools.map((t) => [t.name, t]),
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);
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const controlsDiv = document.getElementById("controls") as HTMLDivElement;
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const chatRootDiv = document.getElementById("chat-root") as HTMLDivElement;
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/**
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* Creates a tool UI instance for the given tool name.
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* This demonstrates the new simplified API where the host manages the full proxy lifecycle.
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*/
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async function createToolUI(
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toolName: string,
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toolInput: Record<string, unknown>,
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) {
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try {
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// Step 1: Create iframe and wait for sandbox proxy ready
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const { iframe, onReady } =
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await setupSandboxProxyIframe(SANDBOX_PROXY_URL);
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chatRootDiv.appendChild(iframe);
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// Wait for sandbox proxy to be ready
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await onReady;
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// Step 2: Create proxy server instance
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const serverCapabilities = client.getServerCapabilities();
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const proxy = new AppBridge(
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client,
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{
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name: "Example MCP UI Host",
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version: "1.0.0",
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},
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{
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openLinks: {},
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serverTools: serverCapabilities?.tools,
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serverResources: serverCapabilities?.resources,
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},
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);
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// Step 3: Register handlers BEFORE connecting
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proxy.oninitialized = () => {
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console.log("[Example] Inner iframe MCP client initialized");
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// Send tool input once iframe is ready
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proxy.sendToolInput({ arguments: toolInput });
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};
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proxy.setRequestHandler(McpUiOpenLinkRequestSchema, async (req) => {
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console.log("[Example] Open link requested:", req.params.url);
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window.open(req.params.url, "_blank", "noopener,noreferrer");
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return { isError: false };
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});
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proxy.setRequestHandler(McpUiMessageRequestSchema, async (req) => {
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console.log("[Example] Message requested:", req.params);
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return { isError: false };
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});
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// Handle size changes by resizing the iframe
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proxy.setNotificationHandler(
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McpUiSizeChangeNotificationSchema,
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async (notif: any) => {
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const { width, height } = notif.params;
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if (width !== undefined) {
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iframe.style.width = `${width}px`;
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}
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if (height !== undefined) {
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iframe.style.height = `${height}px`;
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}
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},
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);
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proxy.setNotificationHandler(
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LoggingMessageNotificationSchema,
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async (notif: any) => {
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console.log("[Tool UI Log]", notif.params);
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},
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);
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// Step 4: Connect proxy to iframe (triggers MCP initialization)
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// Pass iframe.contentWindow as both target and source for proper message filtering
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await proxy.connect(
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new PostMessageTransport(iframe.contentWindow!, iframe.contentWindow!),
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);
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// Step 5: Fetch and send UI resource
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const resourceInfo = await getToolUiResourceUri(client, toolName);
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||||
if (!resourceInfo) {
|
||||
throw new Error(`Tool ${toolName} has no UI resource`);
|
||||
}
|
||||
|
||||
const html = await readToolUiResourceHtml(client, {
|
||||
uri: resourceInfo.uri,
|
||||
});
|
||||
await proxy.sendSandboxResourceReady({ html });
|
||||
|
||||
console.log("[Example] Tool UI setup complete for:", toolName);
|
||||
} catch (error) {
|
||||
console.error("[Example] Error setting up tool UI:", error);
|
||||
}
|
||||
}
|
||||
|
||||
// Create buttons for available tools
|
||||
if ([...Object.keys(tools)].some((n) => n.startsWith("pizza-"))) {
|
||||
for (const t of Object.values(tools)) {
|
||||
if (t.name.startsWith("pizza-")) {
|
||||
controlsDiv.appendChild(
|
||||
Object.assign(document.createElement("button"), {
|
||||
innerText: t.name,
|
||||
onclick: () => createToolUI(t.name, { pizzaTopping: "Mushrooms" }),
|
||||
}),
|
||||
);
|
||||
}
|
||||
}
|
||||
} else {
|
||||
controlsDiv.appendChild(
|
||||
Object.assign(document.createElement("button"), {
|
||||
innerText: "Add MCP UI View",
|
||||
onclick: () =>
|
||||
createToolUI("create-example-ui", { message: "Hello from Host!" }),
|
||||
}),
|
||||
);
|
||||
}
|
||||
});
|
||||
356
examples/simple-host/src/react/UITemplatedToolCallRenderer.tsx
Normal file
356
examples/simple-host/src/react/UITemplatedToolCallRenderer.tsx
Normal file
|
|
@ -0,0 +1,356 @@
|
|||
import { useEffect, useRef, useState } from "react";
|
||||
|
||||
import { Client } from "@modelcontextprotocol/sdk/client/index.js";
|
||||
import {
|
||||
type CallToolResult,
|
||||
type LoggingMessageNotification,
|
||||
type McpError,
|
||||
ErrorCode,
|
||||
} from "@modelcontextprotocol/sdk/types.js";
|
||||
|
||||
import {
|
||||
type McpUiMessageRequest,
|
||||
type McpUiMessageResult,
|
||||
type McpUiOpenLinkRequest,
|
||||
type McpUiOpenLinkResult,
|
||||
AppBridge,
|
||||
PostMessageTransport,
|
||||
} from "@modelcontextprotocol/ext-apps/app-bridge";
|
||||
|
||||
import {
|
||||
getToolUiResourceUri,
|
||||
readToolUiResourceHtml,
|
||||
setupSandboxProxyIframe,
|
||||
} from "../app-host-utils";
|
||||
|
||||
type RequestExtra = Parameters<
|
||||
Parameters<AppBridge["setRequestHandler"]>[1]
|
||||
>[1];
|
||||
|
||||
/**
|
||||
* Props for the UITemplatedToolCallRenderer component.
|
||||
*/
|
||||
export interface UITemplatedToolCallRendererProps {
|
||||
/** URL to the sandbox proxy HTML that will host the tool UI iframe */
|
||||
sandboxProxyUrl: URL;
|
||||
|
||||
/** MCP client connected to the server providing the tool */
|
||||
client: Client;
|
||||
|
||||
/** Name of the MCP tool to render UI for */
|
||||
toolName: string;
|
||||
|
||||
/** Optional pre-fetched resource URI. If not provided, will be fetched via getToolUiResourceUri() */
|
||||
toolResourceUri?: string;
|
||||
|
||||
/** Optional input arguments to pass to the tool UI once it's ready */
|
||||
toolInput?: Record<string, unknown>;
|
||||
|
||||
/** Optional result from tool execution to pass to the tool UI once it's ready */
|
||||
toolResult?: CallToolResult;
|
||||
|
||||
onopenlink?: (
|
||||
params: McpUiOpenLinkRequest["params"],
|
||||
extra: RequestExtra,
|
||||
) => Promise<McpUiOpenLinkResult>;
|
||||
onmessage?: (
|
||||
params: McpUiMessageRequest["params"],
|
||||
extra: RequestExtra,
|
||||
) => Promise<McpUiMessageResult>;
|
||||
onloggingmessage?: (params: LoggingMessageNotification["params"]) => void;
|
||||
|
||||
/** Callback invoked when an error occurs during setup or message handling */
|
||||
onerror?: (error: Error) => void;
|
||||
}
|
||||
|
||||
/**
|
||||
* React component that renders an MCP tool's custom UI in a sandboxed iframe.
|
||||
*
|
||||
* This component manages the complete lifecycle of an MCP-UI tool:
|
||||
* 1. Creates a sandboxed iframe with the proxy HTML
|
||||
* 2. Establishes MCP communication channel between host and iframe
|
||||
* 3. Fetches and loads the tool's UI resource (HTML)
|
||||
* 4. Sends tool inputs and results to the UI when ready
|
||||
* 5. Handles UI actions (intents, link opening, prompts, notifications)
|
||||
* 6. Automatically resizes iframe based on content size changes
|
||||
*
|
||||
* @example
|
||||
* ```tsx
|
||||
* <UITemplatedToolCallRenderer
|
||||
* sandboxProxyUrl={new URL('http://localhost:8765/sandbox_proxy.html')}
|
||||
* client={mcpClient}
|
||||
* toolName="create-chart"
|
||||
* toolInput={{ data: [1, 2, 3], type: 'bar' }}
|
||||
* onUIAction={async (action) => {
|
||||
* if (action.type === 'intent') {
|
||||
* // Handle intent request from UI
|
||||
* console.log('Intent:', action.payload.intent);
|
||||
* }
|
||||
* }}
|
||||
* onerror={(error) => console.error('UI Error:', error)}
|
||||
* />
|
||||
* ```
|
||||
*
|
||||
* **Architecture:**
|
||||
* - Host (this component) ↔ Sandbox Proxy (iframe) ↔ Tool UI (nested iframe)
|
||||
* - Communication uses MCP protocol over postMessage
|
||||
* - Sandbox proxy provides CSP isolation for untrusted tool UIs
|
||||
* - Standard MCP initialization flow determines when UI is ready
|
||||
*
|
||||
* **Lifecycle:**
|
||||
* 1. `setupSandboxProxyIframe()` creates iframe and waits for proxy ready
|
||||
* 2. Component creates `McpUiProxyServer` instance
|
||||
* 3. Registers all handlers (BEFORE connecting to avoid race conditions)
|
||||
* 4. Connects proxy to iframe via `MessageTransport`
|
||||
* 5. MCP initialization completes → `onClientReady` callback fires
|
||||
* 6. Fetches tool UI resource and sends to sandbox proxy
|
||||
* 7. Sends tool inputs/results when iframe signals ready
|
||||
*
|
||||
* @param props - Component props
|
||||
* @returns React element containing the sandboxed tool UI iframe
|
||||
*/
|
||||
export const UITemplatedToolCallRenderer = (
|
||||
props: UITemplatedToolCallRendererProps,
|
||||
) => {
|
||||
const {
|
||||
client,
|
||||
sandboxProxyUrl,
|
||||
toolName,
|
||||
toolResourceUri,
|
||||
toolInput,
|
||||
toolResult,
|
||||
onmessage,
|
||||
onopenlink,
|
||||
onloggingmessage,
|
||||
onerror,
|
||||
} = props;
|
||||
|
||||
// State
|
||||
const [appBridge, setAppBridge] = useState<AppBridge | null>(null);
|
||||
const [iframeReady, setIframeReady] = useState(false);
|
||||
const [error, setError] = useState<Error | null>(null);
|
||||
const containerRef = useRef<HTMLDivElement | null>(null);
|
||||
const iframeRef = useRef<HTMLIFrameElement | null>(null);
|
||||
|
||||
// Use refs for callbacks to avoid effect re-runs when they change
|
||||
const onmessageRef = useRef(onmessage);
|
||||
const onopenlinkRef = useRef(onopenlink);
|
||||
const onloggingmessageRef = useRef(onloggingmessage);
|
||||
const onerrorRef = useRef(onerror);
|
||||
|
||||
useEffect(() => {
|
||||
onmessageRef.current = onmessage;
|
||||
onopenlinkRef.current = onopenlink;
|
||||
onloggingmessageRef.current = onloggingmessage;
|
||||
onerrorRef.current = onerror;
|
||||
});
|
||||
|
||||
useEffect(() => {
|
||||
let mounted = true;
|
||||
|
||||
const setup = async () => {
|
||||
try {
|
||||
const { iframe, onReady } =
|
||||
await setupSandboxProxyIframe(sandboxProxyUrl);
|
||||
|
||||
if (!mounted) return;
|
||||
|
||||
iframeRef.current = iframe;
|
||||
if (containerRef.current) {
|
||||
containerRef.current.appendChild(iframe);
|
||||
}
|
||||
|
||||
await onReady;
|
||||
|
||||
if (!mounted) return;
|
||||
|
||||
const serverCapabilities = client.getServerCapabilities();
|
||||
const appBridge = new AppBridge(
|
||||
client,
|
||||
{
|
||||
name: "Example MCP UI Host",
|
||||
version: "1.0.0",
|
||||
},
|
||||
{
|
||||
openLinks: {},
|
||||
serverTools: serverCapabilities?.tools,
|
||||
serverResources: serverCapabilities?.resources,
|
||||
},
|
||||
);
|
||||
|
||||
// Step 3: Register ALL handlers BEFORE connecting (critical for avoiding race conditions)
|
||||
|
||||
// Hook into the standard MCP initialization to know when the inner iframe is ready
|
||||
appBridge.oninitialized = () => {
|
||||
if (!mounted) return;
|
||||
console.log("[Host] Inner iframe MCP client initialized");
|
||||
setIframeReady(true);
|
||||
};
|
||||
|
||||
// Register handlers passed in via props
|
||||
|
||||
appBridge.onmessage = (params, extra) => {
|
||||
if (!onmessageRef.current) {
|
||||
throw new McpError(ErrorCode.MethodNotFound, "Method not found");
|
||||
}
|
||||
return onmessageRef.current(params, extra);
|
||||
};
|
||||
appBridge.onopenlink = (params, extra) => {
|
||||
if (!onopenlinkRef.current) {
|
||||
throw new McpError(ErrorCode.MethodNotFound, "Method not found");
|
||||
}
|
||||
return onopenlinkRef.current(params, extra);
|
||||
};
|
||||
appBridge.onloggingmessage = (params) => {
|
||||
if (!onloggingmessageRef.current) {
|
||||
throw new McpError(ErrorCode.MethodNotFound, "Method not found");
|
||||
}
|
||||
return onloggingmessageRef.current(params);
|
||||
};
|
||||
|
||||
appBridge.onsizechange = async ({ width, height }) => {
|
||||
if (iframeRef.current) {
|
||||
if (width !== undefined) {
|
||||
iframeRef.current.style.width = `${width}px`;
|
||||
}
|
||||
if (height !== undefined) {
|
||||
iframeRef.current.style.height = `${height}px`;
|
||||
}
|
||||
}
|
||||
};
|
||||
|
||||
// Step 4: NOW connect (triggers MCP initialization handshake)
|
||||
// IMPORTANT: Pass iframe.contentWindow as BOTH target and source to ensure
|
||||
// this proxy only responds to messages from its specific iframe
|
||||
await appBridge.connect(
|
||||
new PostMessageTransport(
|
||||
iframe.contentWindow!,
|
||||
iframe.contentWindow!,
|
||||
),
|
||||
);
|
||||
|
||||
if (!mounted) return;
|
||||
|
||||
// Step 5: Store proxy in state
|
||||
setAppBridge(appBridge);
|
||||
} catch (err) {
|
||||
console.error("[UITemplatedToolCallRenderer] Error:", err);
|
||||
if (!mounted) return;
|
||||
const error = err instanceof Error ? err : new Error(String(err));
|
||||
setError(error);
|
||||
onerrorRef.current?.(error);
|
||||
}
|
||||
};
|
||||
|
||||
setup();
|
||||
|
||||
return () => {
|
||||
mounted = false;
|
||||
// Cleanup: remove iframe from DOM
|
||||
if (
|
||||
iframeRef.current &&
|
||||
containerRef.current?.contains(iframeRef.current)
|
||||
) {
|
||||
containerRef.current.removeChild(iframeRef.current);
|
||||
}
|
||||
};
|
||||
}, [client, sandboxProxyUrl]);
|
||||
|
||||
// Effect 2: Fetch and send UI resource
|
||||
useEffect(() => {
|
||||
if (!appBridge) return;
|
||||
|
||||
let mounted = true;
|
||||
|
||||
const fetchAndSendResource = async () => {
|
||||
try {
|
||||
// Get the resource URI (use prop if provided, otherwise fetch)
|
||||
let resourceInfo: { uri: string };
|
||||
|
||||
if (toolResourceUri) {
|
||||
// When URI is provided directly, assume it's NOT OpenAI Apps SDK format
|
||||
resourceInfo = {
|
||||
uri: toolResourceUri,
|
||||
};
|
||||
console.log(
|
||||
`[Host] Using provided resource URI: ${resourceInfo.uri}`,
|
||||
);
|
||||
} else {
|
||||
console.log(`[Host] Fetching resource URI for tool: ${toolName}`);
|
||||
const info = await getToolUiResourceUri(client, toolName);
|
||||
if (!info) {
|
||||
throw new Error(
|
||||
`Tool ${toolName} has no UI resource (no ui/resourceUri or openai/outputTemplate in tool._meta)`,
|
||||
);
|
||||
}
|
||||
resourceInfo = info;
|
||||
console.log(`[Host] Got resource URI: ${resourceInfo.uri}`);
|
||||
}
|
||||
|
||||
if (!resourceInfo.uri) {
|
||||
throw new Error(`Tool ${toolName}: URI is undefined or empty`);
|
||||
}
|
||||
|
||||
if (!mounted) return;
|
||||
|
||||
// Read the HTML content
|
||||
console.log(`[Host] Reading resource HTML from: ${resourceInfo.uri}`);
|
||||
const html = await readToolUiResourceHtml(client, {
|
||||
uri: resourceInfo.uri,
|
||||
});
|
||||
|
||||
if (!mounted) return;
|
||||
|
||||
// Send the resource to the sandbox proxy
|
||||
console.log("[Host] Sending sandbox resource ready");
|
||||
await appBridge.sendSandboxResourceReady({ html });
|
||||
} catch (err) {
|
||||
if (!mounted) return;
|
||||
const error = err instanceof Error ? err : new Error(String(err));
|
||||
setError(error);
|
||||
onerrorRef.current?.(error);
|
||||
}
|
||||
};
|
||||
|
||||
fetchAndSendResource();
|
||||
|
||||
return () => {
|
||||
mounted = false;
|
||||
};
|
||||
}, [appBridge, toolName, toolResourceUri, client]);
|
||||
|
||||
// Effect 3: Send tool input when ready
|
||||
useEffect(() => {
|
||||
if (appBridge && iframeReady && toolInput) {
|
||||
console.log("[Host] Sending tool input:", toolInput);
|
||||
appBridge.sendToolInput({ arguments: toolInput });
|
||||
}
|
||||
}, [appBridge, iframeReady, toolInput]);
|
||||
|
||||
// Effect 4: Send tool result when ready
|
||||
useEffect(() => {
|
||||
if (appBridge && iframeReady && toolResult) {
|
||||
console.log("[Host] Sending tool result:", toolResult);
|
||||
appBridge.sendToolResult(toolResult);
|
||||
}
|
||||
}, [appBridge, iframeReady, toolResult]);
|
||||
|
||||
// Render
|
||||
return (
|
||||
<div
|
||||
ref={containerRef}
|
||||
style={{
|
||||
width: "100%",
|
||||
height: "100%",
|
||||
display: "flex",
|
||||
flexDirection: "column",
|
||||
}}
|
||||
>
|
||||
{error && (
|
||||
<div style={{ color: "red", padding: "1rem" }}>
|
||||
Error: {error.message}
|
||||
</div>
|
||||
)}
|
||||
</div>
|
||||
);
|
||||
};
|
||||
41
examples/simple-host/src/sandbox.ts
Normal file
41
examples/simple-host/src/sandbox.ts
Normal file
|
|
@ -0,0 +1,41 @@
|
|||
// Double-iframe raw HTML mode (HTML sent via postMessage)
|
||||
const inner = document.createElement("iframe");
|
||||
inner.style = "width:100%; height:100%; border:none;";
|
||||
// sandbox will be set from postMessage payload; default minimal before html arrives
|
||||
inner.setAttribute("sandbox", "allow-scripts allow-same-origin allow-forms");
|
||||
document.body.appendChild(inner);
|
||||
|
||||
// Wait for HTML content from parent
|
||||
window.addEventListener("message", async (event) => {
|
||||
if (event.source === window.parent) {
|
||||
if (
|
||||
event.data &&
|
||||
event.data.method === "ui/notifications/sandbox-resource-ready"
|
||||
) {
|
||||
const { html, sandbox } = event.data.params;
|
||||
if (typeof sandbox === "string") {
|
||||
inner.setAttribute("sandbox", sandbox);
|
||||
}
|
||||
if (typeof html === "string") {
|
||||
inner.srcdoc = html;
|
||||
}
|
||||
} else {
|
||||
if (inner && inner.contentWindow) {
|
||||
inner.contentWindow.postMessage(event.data, "*");
|
||||
}
|
||||
}
|
||||
} else if (event.source === inner.contentWindow) {
|
||||
// Relay messages from inner to parent
|
||||
window.parent.postMessage(event.data, "*");
|
||||
}
|
||||
});
|
||||
|
||||
// Notify parent that proxy is ready to receive HTML (distinct event)
|
||||
window.parent.postMessage(
|
||||
{
|
||||
jsonrpc: "2.0",
|
||||
method: "ui/notifications/sandbox-proxy-ready",
|
||||
params: {},
|
||||
},
|
||||
"*",
|
||||
);
|
||||
Loading…
Reference in a new issue