feat: add sign message method (#323)

Co-authored-by: Roland <[email protected]>

README.md

@@ -261,6 +261,7 @@ Please have a look a the Alby OAuth2 Wallet API:
 
 - accountBalance
 - accountSummary
+- signMessage
 - accountInformation
 - accountValue4Value
 - invoices

src/client.ts

@@ -1,3 +1,4 @@
+import { SignMessageResponse } from "@webbtc/webln-types";
 import { OAuth2Bearer } from "./auth";
 import { keysendParamsFromBoostagram } from "./helpers";
 import { RequestOptions, rest } from "./request";
@@ -20,6 +21,7 @@ import {
   SendPaymentResponse,
   SendBoostagramToAlbyRequestParams,
   SwapInfoResponse,
+  SignMessageRequestParams,
 } from "./types";
 
 export class Client {
@@ -52,6 +54,20 @@ export class Client {
     });
   }
 
+  signMessage(
+    message: SignMessageRequestParams,
+    request_options?: Partial<RequestOptions>,
+  ): Promise<SignMessageResponse> {
+    return rest({
+      auth: this.auth,
+      ...this.defaultRequestOptions,
+      ...request_options,
+      endpoint: `/signatures`,
+      request_body: message,
+      method: "POST",
+    });
+  }
+
   accountSummary(
     // eslint-disable-next-line @typescript-eslint/ban-types
     params: {},

src/types.ts

@@ -255,6 +255,10 @@ export type GetAccountBalanceResponse = {
   unit: string;
 };
 
+export type SignMessageRequestParams = {
+  message: string;
+};
+
 export type GetAccountInformationResponse = {
   identifier: string;
   email: string;