introduce frame-core, frame-host, frame-sdk packages

package.json

@@ -17,6 +17,7 @@
     "test": "./node_modules/.bin/turbo run test",
     "test:ci": "./node_modules/.bin/turbo run test:ci -- --passWithNoTests",
     "lint": "./node_modules/.bin/turbo run lint --parallel",
+    "lint:fix": "./node_modules/.bin/turbo run lint:fix --parallel",
     "lint:ci": "./node_modules/.bin/turbo run lint:ci --parallel",
     "prepare": "husky install",
     "version-packages": "changeset version",

packages/frame-core/.gitignore

@@ -0,0 +1,21 @@
+# Logs
+logs
+*.log
+yarn-debug.log*
+yarn-error.log*
+
+node_modules
+dist
+dist-ssr
+*.local
+
+# Editor directories and files
+.vscode/*
+!.vscode/extensions.json
+.idea
+.DS_Store
+*.suo
+*.ntvs*
+*.njsproj
+*.sln
+*.sw?

packages/frame-core/package.json

@@ -0,0 +1,23 @@
+{
+  "name": "@farcaster/frame-core",
+  "version": "0.0.1",
+  "main": "dist/index.js",
+  "scripts": {
+    "clean": "rimraf dist",
+    "prebuild": "npm run clean",
+    "build": "tsc",
+    "preversion": "npm run build",
+    "postversion": "git push --follow-tags"
+  },
+  "files": [
+    "dist",
+    "src"
+  ],
+  "devDependencies": {
+    "rimraf": "^3.0.2",
+    "typescript": "^5.6.3"
+  },
+  "dependencies": {
+    "ox": "^0.1.6"
+  }
+}

packages/frame-core/src/index.ts

@@ -0,0 +1 @@
+export * from "./types";

packages/frame-core/src/types.ts

@@ -0,0 +1,40 @@
+import type { Provider, RpcSchema } from "ox";
+
+export type SetPrimaryButton = (options: {
+  text: string;
+  loading?: boolean;
+  disabled?: boolean;
+  hidden?: boolean;
+}) => void;
+
+export type EthProviderRequest = Provider.RequestFn<RpcSchema.Default>;
+
+export type AccountLocation = {
+  placeId: string;
+ /**
+  * Human-readable string describing the location
+  */
+  description: string;
+}
+
+export type FrameContext = {
+  fid: number;
+  custodyAddress: [];
+  username?: string;
+  displayName?: string;
+ /**
+  * Profile image URL
+  */
+  pfpUrl?: string;
+  location?: AccountLocation;
+}
+
+export type FrameHost = {
+  context: FrameContext;
+  close: () => void;
+  ready: () => void;
+  openUrl: (url: string) => void;
+  setPrimaryButton: SetPrimaryButton;
+  ethProviderRequest: EthProviderRequest;
+}
+

packages/frame-core/tsconfig.json

@@ -0,0 +1,14 @@
+{
+  "include": ["src"],
+  "compilerOptions": {
+    "target": "es2018",
+    "outDir": "dist",
+    "lib": ["dom", "esnext"],
+    "declaration": true,
+    "moduleResolution": "node",
+    "sourceMap": true,
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true
+  }
+}

packages/frame-host/.gitignore

@@ -0,0 +1,21 @@
+# Logs
+logs
+*.log
+yarn-debug.log*
+yarn-error.log*
+
+node_modules
+dist
+dist-ssr
+*.local
+
+# Editor directories and files
+.vscode/*
+!.vscode/extensions.json
+.idea
+.DS_Store
+*.suo
+*.ntvs*
+*.njsproj
+*.sln
+*.sw?

packages/frame-host/package.json

@@ -0,0 +1,29 @@
+{
+  "name": "@farcaster/frame-host",
+  "version": "0.0.1",
+  "main": "dist/index.js",
+  "scripts": {
+    "clean": "rimraf dist",
+    "prebuild": "npm run clean",
+    "build": "tsc",
+    "preversion": "npm run build",
+    "postversion": "git push --follow-tags"
+  },
+  "files": [
+    "dist",
+    "src"
+  ],
+  "devDependencies": {
+    "react-native-webview": "^13.8.2",
+    "rimraf": "^3.0.2",
+    "typescript": "^5.6.3"
+  },
+  "peerDependencies": {
+    "comlink": ">=4.0.0",
+    "react": ">=18.0.0",
+    "react-native-webview": ">=13.0.0"
+  },
+  "dependencies": {
+    "@farcaster/frame-core": "*"
+  }
+}

packages/frame-host/src/adapter.ts

@@ -0,0 +1,39 @@
+import * as Comlink from "comlink";
+import { RefObject, useCallback, useEffect, useRef } from "react";
+import WebView, { WebViewMessageEvent, WebViewProps } from "react-native-webview";
+import { WebViewEndpoint, createWebViewRpcEndpoint } from "./endpoint";
+import type { FrameHost } from "@farcaster/frame-core";
+
+/**
+ * Returns a handler of RPC message from WebView.
+ */
+export function useWebViewRpcAdapter(webViewRef: RefObject<WebView>, sdk: FrameHost) {
+  const endpointRef = useRef<
+    WebViewEndpoint & {
+      emit: (data: any) => void;
+    }
+  >();
+
+  const onMessage: WebViewProps["onMessage"] = useCallback(
+    (e: WebViewMessageEvent) => {
+      endpointRef.current?.onMessage(e);
+    },
+    [endpointRef],
+  );
+
+  useEffect(() => {
+    const endpoint = createWebViewRpcEndpoint(webViewRef);
+    endpointRef.current = endpoint;
+
+    Comlink.expose(sdk, endpoint);
+
+    return () => {
+      endpointRef.current = undefined;
+    };
+  }, [webViewRef, sdk]);
+
+  return {
+    onMessage,
+    emit: endpointRef.current?.emit,
+  };
+}

packages/frame-host/src/endpoint.ts

@@ -0,0 +1,81 @@
+import * as Comlink from "comlink";
+import { RefObject } from "react";
+import WebView, { WebViewMessageEvent } from "react-native-webview";
+
+export const SYMBOL_IGNORING_RPC_RESPONSE_ERROR: symbol = Symbol();
+
+export type WebViewEndpoint = Comlink.Endpoint & {
+  /**
+   * Manually distribute events to listeners as an alternative to `document.addEventHandler` which is unavailable in React Native.
+   */
+  onMessage: (e: WebViewMessageEvent) => void;
+};
+
+/**
+ * An endpoint of communicating with WebView
+ */
+export function createWebViewRpcEndpoint(ref: RefObject<WebView>): WebViewEndpoint & { emit: (data: any) => void } {
+  const listeners: EventListenerOrEventListenerObject[] = [];
+  return {
+    addEventListener: (type, listener) => {
+      if (type !== "message") {
+        throw Error(`Got an unexpected event type "${type}". Expected "message".`);
+      }
+      listeners.push(listener);
+    },
+    removeEventListener: (type, listener) => {
+      if (type !== "message") {
+        throw Error(`Got an unexpected event type "${type}". Expected "message".`);
+      }
+      listeners.splice(listeners.findIndex((l) => l === listener));
+    },
+    postMessage: (data) => {
+      if (!ref.current) {
+        if ("value" in data && data.value === SYMBOL_IGNORING_RPC_RESPONSE_ERROR) {
+          return;
+        }
+        throw Error("Failed to return RPC response to WebView via postMessage");
+      }
+      console.debug("[webview:res]", data);
+      const dataStr = JSON.stringify(data);
+      return ref.current.injectJavaScript(`
+        console.debug('[webview:res]', ${dataStr});
+        document.dispatchEvent(new MessageEvent('FarcasterFrameCallback', { data: ${dataStr} }));
+      `);
+    },
+    onMessage: (e) => {
+      const data = JSON.parse(e.nativeEvent.data);
+      console.debug("[webview:req]", data);
+      const messageEvent = new MessageEvent(data);
+      listeners.forEach((l) => {
+        if (typeof l === "function") {
+          // Actually, messageEvent doesn't satisfy Event interface,
+          // but it satisfies the minimum properties that Comlink's listener requires.
+          l(messageEvent as unknown as Event);
+        } else {
+          l.handleEvent(messageEvent as unknown as Event);
+        }
+      });
+    },
+    emit: (data) => {
+      if (!ref.current) {
+        throw Error("Failed to send Event to WebView via postMessage");
+      }
+      console.debug("[webview:emit]", data);
+      const dataStr = JSON.stringify(data);
+      return ref.current.injectJavaScript(`
+        console.debug('[webview:emit]', ${dataStr});
+        document.dispatchEvent(new MessageEvent('FarcasterFrameEvent', { data: ${dataStr} }));
+      `);
+    },
+  };
+}
+
+/**
+ * Standard MessageEvent is unavailable in React Native since it's part of HTML Standard.
+ * Instead, implement our own MessageEvent with the minimum properties required by Comlink implementation.
+ */
+class MessageEvent {
+  public origin = "ReactNativeWebView";
+  constructor(public data: unknown) {}
+}

packages/frame-host/src/index.ts

@@ -0,0 +1,2 @@
+export * from "./adapter";
+export * from "./endpoint";

packages/frame-host/tsconfig.json

@@ -0,0 +1,14 @@
+{
+  "include": ["src"],
+  "compilerOptions": {
+    "target": "es2018",
+    "outDir": "dist",
+    "lib": ["dom", "esnext"],
+    "declaration": true,
+    "moduleResolution": "node",
+    "sourceMap": true,
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true
+  }
+}

packages/frame-sdk/.eslintrc.cjs

@@ -0,0 +1,7 @@
+module.exports = {
+  root: true,
+  env: { browser: true, es2020: true },
+  extends: ["eslint:recommended", "plugin:@typescript-eslint/recommended"],
+  ignorePatterns: ["dist", ".eslintrc.cjs"],
+  parser: "@typescript-eslint/parser",
+};

packages/frame-sdk/.gitignore

@@ -0,0 +1,21 @@
+# Logs
+logs
+*.log
+yarn-debug.log*
+yarn-error.log*
+
+node_modules
+dist
+dist-ssr
+*.local
+
+# Editor directories and files
+.vscode/*
+!.vscode/extensions.json
+.idea
+.DS_Store
+*.suo
+*.ntvs*
+*.njsproj
+*.sln
+*.sw?

packages/frame-sdk/CHANGELOG.md

@@ -0,0 +1 @@
+# @farcaster/frame-kit

packages/frame-sdk/README.md

@@ -0,0 +1 @@
+# `@farcaster/frame-kit`

packages/frame-sdk/package.json

@@ -0,0 +1,29 @@
+{
+  "name": "@farcaster/frame-sdk",
+  "version": "0.0.1",
+  "main": "dist/index.js",
+  "scripts": {
+    "clean": "rimraf dist",
+    "prebuild": "npm run clean",
+    "build": "tsc",
+    "typecheck": "tsc --noEmit",
+    "preversion": "npm run build",
+    "postversion": "git push --follow-tags"
+  },
+  "files": [
+    "dist",
+    "src"
+  ],
+  "devDependencies": {
+    "rimraf": "^6.0.1",
+    "typescript": "^5.6.3"
+  },
+  "dependencies": {
+    "@farcaster/frame-core": "*",
+    "comlink": "^4.4.2",
+    "eventemitter3": "^5.0.1"
+  },
+  "peerDependencies": {
+    "ox": "^0.2.2"
+  }
+}

packages/frame-sdk/src/endpoint.ts

@@ -0,0 +1,19 @@
+import { type Endpoint, windowEndpoint } from "comlink";
+
+const webViewEndpoint: Endpoint = {
+  postMessage: (data: unknown) => {
+    console.debug("[webview:req]", data);
+    window.ReactNativeWebView.postMessage(JSON.stringify(data));
+  },
+  addEventListener: (_, listener, ...args) => {
+    document.addEventListener("FarcasterFrameCallback", listener, ...args);
+  },
+  removeEventListener: (_, listener) => {
+    document.removeEventListener("FarcasterFrameCallback", listener);
+  },
+};
+
+export const endpoint = window?.ReactNativeWebView
+  ? webViewEndpoint
+  : // TODO fallback cleanly when not in iFrame or webview
+    windowEndpoint(window?.parent ?? window);

packages/frame-sdk/src/frameHost.ts

@@ -0,0 +1,5 @@
+import { wrap } from "comlink";
+import { endpoint } from "./endpoint";
+import { FrameHost } from "@farcaster/frame-core";
+
+export const frameHost = wrap<FrameHost>(endpoint);

packages/frame-sdk/src/index.ts

@@ -0,0 +1,2 @@
+export * from "./sdk";
+export * from "./provider";