the important stuff

rpc.ts

@@ -0,0 +1,47 @@
+import type { BlockCountRPC } from "./rpc_types";
+
+/** Implement this interface if the built-in RPC class does not fit your needs. The easiest way to do this is by just extending the built-in RPC class */
+export interface RPCInterface {
+  readonly rpc_url: string;
+  use_pending: boolean;
+  call(payload: Record<string, any>): Promise<Record<string, string>>;
+  get_block_count(): Promise<BlockCountRPC>;
+  //
+}
+
+/** Sends RPC requests to the RPC node, also has wrappers for actions that only read the network (write actions are handled by the Wallet class) */
+export class RPC implements RPCInterface {
+  readonly rpc_url: string;
+
+  readonly use_pending: boolean;
+
+  /** HTTP headers to send with any RPC requests */
+  headers: Record<string, string> | undefined;
+
+  /**
+   * @param {boolean} [use_pending = false] If true, uses "pending" instead of "receivable" in RPC action names, for compatibility with older versions of the node
+  */
+  constructor(rpc_url: string, use_pending: boolean = false) {
+    this.rpc_url = rpc_url;
+    this.use_pending = use_pending;
+  }
+  /** The function that sends the RPC POST request */
+  async call(payload: Record<string, any>): Promise<Record<string, any>> {
+    const resp = await fetch(this.rpc_url, {
+      method: "POST",
+      headers: this.headers ?? {},
+      body: JSON.stringify(payload),
+    });
+    if (!resp.ok) throw Error(`Request to RPC node failed with status code ${resp.status}`);
+    const resp_json = await resp.json();
+    if (resp_json.error) throw Error(`RPC node response: ${resp_json.error}`);
+    return resp_json;
+  }
+  /** See https://docs.nano.org/commands/rpc-protocol/#block_count */
+  async get_block_count(): Promise<BlockCountRPC> {
+    return (await this.call({
+      "action": "block_count",
+    })) as BlockCountRPC;
+  }
+  //
+}