Added Chainstack provider (#2741).

docs.wrm/links/projects.txt

@@ -1,5 +1,6 @@
 link-alchemy [Alchemy](https://alchemy.com/?a=ethers)
 link-ankr [Ankr](https://www.ankr.com)
+link-chainstack [Chainstack](https://chainstack.com)
 link-cloudflare [Cloudflare](https://developers.cloudflare.com/distributed-web/ethereum-gateway/)
 link-ens [ENS](https://ens.domains/)
 link-ethereum [Ethereum](https://ethereumorg)

src.ts/_tests/create-provider.ts

@@ -2,6 +2,7 @@ import {
     AlchemyProvider,
 //    AnkrProvider,
 //    CloudflareProvider,
+    ChainstackProvider,
     EtherscanProvider,
     InfuraProvider,
 //    PocketProvider,
@@ -48,6 +49,13 @@ const ProviderCreators: Array<ProviderCreator> = [
         }
     },
     */
+    {
+        name: "ChainstackProvider",
+        networks: [ "default", "mainnet", "arbitrum", "bnb", "matic" ],
+        create: function(network: string) {
+            return new ChainstackProvider(network);
+        }
+    },
     {
         name: "EtherscanProvider",
         networks: ethNetworks,
@@ -143,7 +151,7 @@ export function getProvider(provider: string, network: string): null | AbstractP
 
 export function checkProvider(provider: string, network: string): boolean {
     const creator = getCreator(provider);
-    return (creator != null);
+    return (creator != null && creator.networks.indexOf(network) >= 0);
 }
 
 export function connect(network: string): AbstractProvider {

src.ts/ethers.ts

@@ -69,8 +69,9 @@ export {
 
     BrowserProvider,
 
-    AlchemyProvider, AnkrProvider, CloudflareProvider, EtherscanProvider,
-    InfuraProvider, InfuraWebSocketProvider, PocketProvider, QuickNodeProvider,
+    AlchemyProvider, AnkrProvider, ChainstackProvider, CloudflareProvider,
+    EtherscanProvider, InfuraProvider, InfuraWebSocketProvider, PocketProvider,
+    QuickNodeProvider,
 
     IpcSocketProvider, SocketProvider, WebSocketProvider,
 

src.ts/providers/default-provider.ts

@@ -3,6 +3,7 @@ import { assert } from "../utils/index.js";
 
 import { AnkrProvider } from "./provider-ankr.js";
 import { AlchemyProvider } from "./provider-alchemy.js";
+import { ChainstackProvider } from "./provider-chainstack.js";
 import { CloudflareProvider } from "./provider-cloudflare.js";
 import { EtherscanProvider } from "./provider-etherscan.js";
 import { InfuraProvider } from "./provider-infura.js";
@@ -48,6 +49,7 @@ const Testnets = "goerli kovan sepolia classicKotti optimism-goerli arbitrum-goe
  *  - ``"alchemy"``
  *  - ``"ankr"``
  *  - ``"cloudflare"``
+ *  - ``"chainstack"``
  *  - ``"etherscan"``
  *  - ``"infura"``
  *  - ``"publicPolygon"``
@@ -117,6 +119,12 @@ export function getDefaultProvider(network?: string | Networkish | WebSocketLike
         } catch (error) { }
     }
 
+    if (allowService("chainstack")) {
+        try {
+            providers.push(new ChainstackProvider(network, options.chainstack));
+        } catch (error) { }
+    }
+
     if (allowService("cloudflare")) {
         try {
             providers.push(new CloudflareProvider(network));

src.ts/providers/index.ts

@@ -62,6 +62,7 @@ export { BrowserProvider } from "./provider-browser.js";
 export { AlchemyProvider } from "./provider-alchemy.js";
 export { AnkrProvider } from "./provider-ankr.js";
 export { CloudflareProvider } from "./provider-cloudflare.js";
+export { ChainstackProvider } from "./provider-chainstack.js";
 export { EtherscanProvider, EtherscanPlugin } from "./provider-etherscan.js";
 export { InfuraProvider, InfuraWebSocketProvider } from "./provider-infura.js";
 export { PocketProvider } from "./provider-pocket.js";

src.ts/providers/provider-chainstack.ts

@@ -0,0 +1,113 @@
+/**
+ *  [[link-chainstack]] provides a third-party service for connecting to
+ *  various blockchains over JSON-RPC.
+ *
+ *  **Supported Networks**
+ *
+ *  - Ethereum Mainnet (``mainnet``)
+ *  - Arbitrum (``arbitrum``)
+ *  - BNB Smart Chain Mainnet (``bnb``)
+ *  - Polygon (``matic``)
+ *
+ *  @_subsection: api/providers/thirdparty:Chainstack  [providers-chainstack]
+ */
+import {
+    defineProperties, FetchRequest, assertArgument
+} from "../utils/index.js";
+
+import { showThrottleMessage } from "./community.js";
+import { Network } from "./network.js";
+import { JsonRpcProvider } from "./provider-jsonrpc.js";
+
+import type { AbstractProvider } from "./abstract-provider.js";
+import type { CommunityResourcable } from "./community.js";
+import type { Networkish } from "./network.js";
+
+
+function getApiKey(name: string): string {
+    switch (name) {
+        case "mainnet": return "39f1d67cedf8b7831010a665328c9197";
+        case "arbitrum": return "0550c209db33c3abf4cc927e1e18cea1"
+        case "bnb": return "98b5a77e531614387366f6fc5da097f8";
+        case "matic": return "cd9d4d70377471aa7c142ec4a4205249";
+    }
+
+    assertArgument(false, "unsupported network", "network", name);
+}
+
+function getHost(name: string): string {
+    switch(name) {
+        case "mainnet":
+            return "ethereum-mainnet.core.chainstack.com";
+        case "arbitrum":
+            return "arbitrum-mainnet.core.chainstack.com";
+        case "bnb":
+            return "bsc-mainnet.core.chainstack.com";
+        case "matic":
+            return "polygon-mainnet.core.chainstack.com";
+    }
+
+    assertArgument(false, "unsupported network", "network", name);
+}
+
+/**
+ *  The **ChainstackProvider** connects to the [[link-chainstack]]
+ *  JSON-RPC end-points.
+ *
+ *  By default, a highly-throttled API key is used, which is
+ *  appropriate for quick prototypes and simple scripts. To
+ *  gain access to an increased rate-limit, it is highly
+ *  recommended to [sign up here](link-chainstack).
+ */
+export class ChainstackProvider extends JsonRpcProvider implements CommunityResourcable {
+    /**
+     *  The API key for the Chainstack connection.
+     */
+    readonly apiKey!: string;
+
+    /**
+     *  Creates a new **ChainstackProvider**.
+     */
+    constructor(_network?: Networkish, apiKey?: null | string) {
+        if (_network == null) { _network = "mainnet"; }
+        const network = Network.from(_network);
+
+        if (apiKey == null) { apiKey = getApiKey(network.name); }
+
+        const request = ChainstackProvider.getRequest(network, apiKey);
+        super(request, network, { staticNetwork: network });
+
+        defineProperties<ChainstackProvider>(this, { apiKey });
+    }
+
+    _getProvider(chainId: number): AbstractProvider {
+        try {
+            return new ChainstackProvider(chainId, this.apiKey);
+        } catch (error) { }
+        return super._getProvider(chainId);
+    }
+
+    isCommunityResource(): boolean {
+        return (this.apiKey === getApiKey(this._network.name));
+    }
+
+    /**
+     *  Returns a prepared request for connecting to %%network%%
+     *  with %%apiKey%% and %%projectSecret%%.
+     */
+    static getRequest(network: Network, apiKey?: null | string): FetchRequest {
+        if (apiKey == null) { apiKey = getApiKey(network.name); }
+
+        const request = new FetchRequest(`https:/\/${ getHost(network.name) }/${ apiKey }`);
+        request.allowGzip = true;
+
+        if (apiKey === getApiKey(network.name)) {
+            request.retryFunc = async (request, response, attempt) => {
+                showThrottleMessage("ChainstackProvider");
+                return true;
+            };
+        }
+
+        return request;
+    }
+}