Added EIP-6963 discovery to BrowserProvider.

Author: ricmoo

docs.wrm/links/specs.txt

@@ -33,6 +33,7 @@ link-eip-2718 [EIP-2718](https://eips.ethereum.org/EIPS/eip-2718)
 link-eip-2930 [EIP-2930](https://eips.ethereum.org/EIPS/eip-2930)
 link-eip-4788 [EIP-4844](https://eips.ethereum.org/EIPS/eip-4788)
 link-eip-4844 [EIP-4844](https://eips.ethereum.org/EIPS/eip-4844)
+link-eip-6963 [EIP-1193](https://eips.ethereum.org/EIPS/eip-6963)
 
 # Open Standards
 link-base58 [Base58](https://en.bitcoinwiki.org/wiki/Base58)

src.ts/ethers.ts

@@ -168,14 +168,16 @@ export type {
 
     AbstractProviderOptions, BrowserProviderOptions, FallbackProviderOptions,
 
-    AbstractProviderPlugin, BlockParams, BlockTag, ContractRunner, DebugEventBrowserProvider,
-    Eip1193Provider, EventFilter, Filter, FilterByBlockHash, GasCostParameters,
-    JsonRpcApiProviderOptions, JsonRpcError, JsonRpcPayload, JsonRpcResult,
-    JsonRpcTransactionRequest, LogParams, MinedBlock, MinedTransactionResponse, Networkish,
-    OrphanFilter, PerformActionFilter, PerformActionRequest, PerformActionTransaction,
-    PreparedTransactionRequest, ProviderEvent, Subscriber, Subscription, TopicFilter,
-    TransactionReceiptParams, TransactionRequest, TransactionResponseParams,
-    WebSocketCreator, WebSocketLike
+    AbstractProviderPlugin, BlockParams, BlockTag, BrowserDiscoverOptions,
+    ContractRunner, DebugEventBrowserProvider, Eip1193Provider,
+    Eip6963ProviderInfo, EventFilter, Filter, FilterByBlockHash,
+    GasCostParameters, JsonRpcApiProviderOptions, JsonRpcError,
+    JsonRpcPayload, JsonRpcResult, JsonRpcTransactionRequest, LogParams,
+    MinedBlock, MinedTransactionResponse, Networkish, OrphanFilter,
+    PerformActionFilter, PerformActionRequest, PerformActionTransaction,
+    PreparedTransactionRequest, ProviderEvent, Subscriber, Subscription,
+    TopicFilter, TransactionReceiptParams, TransactionRequest,
+    TransactionResponseParams, WebSocketCreator, WebSocketLike
 } from "./providers/index.js";
 
 export type {

src.ts/providers/index.ts

@@ -114,7 +114,8 @@ export type {
 } from "./provider.js";
 
 export type {
-    BrowserProviderOptions, DebugEventBrowserProvider, Eip1193Provider
+    BrowserDiscoverOptions, BrowserProviderOptions, DebugEventBrowserProvider,
+    Eip1193Provider, Eip6963ProviderInfo
 } from "./provider-browser.js";
 
 export type { FallbackProviderOptions } from "./provider-fallback.js";

src.ts/providers/provider-browser.ts

@@ -36,14 +36,69 @@ export type DebugEventBrowserProvider = {
     error: Error
 };
 
+/**
+ *  Provider info provided by the [[link-eip-6963]] discovery mechanism.
+ */
+export interface Eip6963ProviderInfo {
+    uuid: string;
+    name: string;
+    icon: string;
+    rdns: string;
+}
+
+interface Eip6963ProviderDetail {
+    info: Eip6963ProviderInfo;
+    provider: Eip1193Provider;
+}
+
+interface Eip6963Announcement {
+    type: "eip6963:announceProvider";
+    detail: Eip6963ProviderDetail
+}
+
 export type BrowserProviderOptions = {
     polling?: boolean;
     staticNetwork?: null | boolean | Network;
 
     cacheTimeout?: number;
     pollingInterval?: number;
+
+    providerInfo?: Eip6963ProviderInfo;
 };
 
+/**
+ *  Specifies how [[link-eip-6963]] discovery should proceed.
+ *
+ *  See: [[BrowserProvider-discover]]
+ */
+export interface BrowserDiscoverOptions {
+    /**
+     *  Override provider detection with this provider.
+     */
+    provider?: Eip1193Provider;
+
+    /**
+     *  Duration to wait to detect providers. (default: 300ms)
+     */
+    timeout?: number;
+
+    /**
+     *  Return the first detected provider. Otherwise wait for %%timeout%%
+     *  and allowing filtering before selecting the desired provider.
+     */
+    anyProvider?: boolean;
+
+    /**
+     *  Use the provided window context. Useful in non-standard
+     *  environments or to hijack where a provider comes from.
+     */
+    window?: any;
+}
+
+// @TODO: Future, provide some sort of filter mechansm callback along
+//        with exposing the following types
+
+
 /**
  *  A **BrowserProvider** is intended to wrap an injected provider which
  *  adheres to the [[link-eip-1193]] standard, which most (if not all)
@@ -52,11 +107,14 @@ export type BrowserProviderOptions = {
 export class BrowserProvider extends JsonRpcApiPollingProvider {
     #request: (method: string, params: Array<any> | Record<string, any>) => Promise<any>;
 
+    #providerInfo: null | Eip6963ProviderInfo;
+
     /**
      *  Connect to the %%ethereum%% provider, optionally forcing the
      *  %%network%%.
      */
     constructor(ethereum: Eip1193Provider, network?: Networkish, _options?: BrowserProviderOptions) {
+
         // Copy the options
         const options: JsonRpcApiProviderOptions = Object.assign({ },
           ((_options != null) ? _options: { }),
@@ -66,6 +124,11 @@ export class BrowserProvider extends JsonRpcApiPollingProvider {
 
         super(network, options);
 
+        this.#providerInfo = null;
+        if (_options && _options.providerInfo) {
+            this.#providerInfo = _options.providerInfo;
+        }
+
         this.#request = async (method: string, params: Array<any> | Record<string, any>) => {
             const payload = { method, params };
             this.emit("debug", { action: "sendEip1193Request", payload });
@@ -84,6 +147,10 @@ export class BrowserProvider extends JsonRpcApiPollingProvider {
         };
     }
 
+    get providerInfo(): null | Eip6963ProviderInfo {
+        return this.#providerInfo;
+    }
+
     async send(method: string, params: Array<any> | Record<string, any>): Promise<any> {
         await this._start();
 
@@ -109,7 +176,7 @@ export class BrowserProvider extends JsonRpcApiPollingProvider {
         error = JSON.parse(JSON.stringify(error));
 
         // EIP-1193 gives us some machine-readable error codes, so rewrite
-        // them into 
+        // them into Ethers standard errors.
         switch (error.error.code || -1) {
             case 4001:
                 error.error.message = `ethers-user-denied: ${ error.error.message }`;
@@ -142,9 +209,7 @@ export class BrowserProvider extends JsonRpcApiPollingProvider {
 
         if (!(await this.hasSigner(address))) {
             try {
-                //const resp = 
                 await this.#request("eth_requestAccounts", [ ]);
-                //console.log("RESP", resp);
 
             } catch (error: any) {
                 const payload = error.payload;
@@ -154,4 +219,60 @@ export class BrowserProvider extends JsonRpcApiPollingProvider {
 
         return await super.getSigner(address);
     }
+
+    /**
+     *  Discover and connect to a Provider in the Browser using the
+     *  [[link-eip-6963]] discovery mechanism. If no providers are
+     *  present, ``null`` is resolved.
+     */
+    static async discover(options?: BrowserDiscoverOptions): Promise<null | BrowserProvider> {
+        if (options == null) { options = { }; }
+
+        if (options.provider) {
+            return new BrowserProvider(options.provider);
+        }
+
+        const context = options.window ? options.window:
+            (typeof(window) !== "undefined") ? window: null;
+
+        if (context == null) { return null; }
+
+        const anyProvider = options.anyProvider;
+        if (anyProvider && context.ethereum) {
+            return new BrowserProvider(context.ethereum);
+        }
+
+        const timeout = options.timeout ? options.timeout: 300;
+        if (timeout === 0) { return null; }
+
+        return await (new Promise((resolve) => {
+            let found: Array<any> = [ ];
+
+            const addProvider = (event: Eip6963Announcement) => {
+                found.push(event.detail);
+                if (anyProvider) { finalize(); }
+            };
+
+            const finalize = () => {
+                clearTimeout(timer);
+                if (found.length) {
+                    const { provider, info } = found[0];
+                    resolve(new BrowserProvider(provider, undefined, {
+                        providerInfo: info
+                    }));
+                } else {
+                    resolve(null);
+                }
+                context.removeEventListener(<any>"eip6963:announceProvider",
+                  addProvider);
+            };
+
+            const timer = setTimeout(() => { finalize(); }, timeout);
+
+            context.addEventListener(<any>"eip6963:announceProvider",
+              addProvider);
+
+            context.dispatchEvent(new Event("eip6963:requestProvider"));
+        }));
+    }
 }