BunqContext.ts•6.19 kB
import { getPublicKey, signRequestBody } from "../utils/signature";
export interface BunqToken {
accessToken: string;
installationToken: string;
sessionToken: string;
userId: number;
displayName: string;
flow: "oauth" | "api-key";
}
export class BunqContext {
#accessToken?: string;
#retrievedToken: BunqToken | null = null;
constructor(accessToken?: string) {
this.#accessToken = accessToken;
}
get token(): BunqToken {
if (!this.#retrievedToken) {
throw new Error("Error getting token: Bunq context not initialized");
}
return this.#retrievedToken;
}
get userId(): number {
if (!this.#retrievedToken) {
throw new Error("Error getting userId: Bunq context not initialized");
}
return this.#retrievedToken.userId;
}
async initialize(): Promise<BunqToken> {
if (this.#retrievedToken) {
return this.#retrievedToken;
}
if (!this.#accessToken) {
throw new Error("Access token required for initialization");
}
const pubKey = await getPublicKey();
// 1. Create installation
const installationToken = await this.createInstallation(pubKey);
// 2. Register device server
await this.registerDeviceServer(installationToken);
// 3. Start session
const { sessionToken, userId, displayName, flow } = await this.startSession(installationToken);
this.#retrievedToken = {
accessToken: this.#accessToken,
installationToken,
sessionToken,
userId,
displayName,
flow,
};
return this.#retrievedToken;
}
private async createInstallation(publicKey: string): Promise<string> {
const response = await fetch("https://api.bunq.com/v1/installation", {
method: "POST",
headers: {
"Content-Type": "application/json",
"User-Agent": "bunq-mcp",
},
body: JSON.stringify({
client_public_key: publicKey,
}),
});
if (!response.ok) {
throw new Error(`Installation failed: ${await response.text()}`);
}
interface BunqInstallationResponse {
Response: [
{
Id: { id: number };
},
{
Token: {
id: number;
created: string;
updated: string;
token: string;
};
},
{
ServerPublicKey: {
server_public_key: string;
};
},
];
}
const data = (await response.json()) as BunqInstallationResponse;
return data.Response[1].Token.token;
}
private async registerDeviceServer(installationToken: string): Promise<number> {
if (!this.#accessToken) {
throw new Error("Access token required for device registration");
}
const response = await fetch("https://api.bunq.com/v1/device-server", {
method: "POST",
headers: {
"Content-Type": "application/json",
"X-Bunq-Client-Authentication": installationToken,
},
body: JSON.stringify({
description: "Bunq MCP Integration",
secret: this.#accessToken,
permitted_ips: ["*"],
}),
});
if (!response.ok) {
throw new Error(`Device server registration failed: ${await response.text()}`);
}
const data = (await response.json()) as {
Response: [{ Id: { id: number } }];
};
return data.Response[0].Id.id;
}
private async startSession(installationToken: string): Promise<{
userId: number;
displayName: string;
sessionToken: string;
flow: "oauth" | "api-key";
}> {
if (!this.#accessToken) {
throw new Error("Access token required for session creation");
}
const body = JSON.stringify({
secret: this.#accessToken,
});
const signature = await signRequestBody(body);
const response = await fetch("https://api.bunq.com/v1/session-server", {
method: "POST",
headers: {
"Content-Type": "application/json",
"X-Bunq-Client-Authentication": installationToken,
"X-Bunq-Client-Signature": signature,
},
body,
});
if (!response.ok) {
throw new Error(`Session creation failed: ${await response.text()}`);
}
const data = (await response.json()) as {
Response: [
any,
{
Token: {
token: string;
};
},
{
UserApiKey: {
granted_by_user: {
UserPerson: {
id: number;
display_name: string;
};
};
};
UserPerson: {
id: number;
display_name: string;
};
},
];
};
if (data.Response[2].UserApiKey) {
return {
userId: data.Response[2].UserApiKey.granted_by_user.UserPerson.id,
displayName: data.Response[2].UserApiKey.granted_by_user.UserPerson.display_name,
sessionToken: data.Response[1].Token.token,
flow: "oauth",
};
}
if (data.Response[2].UserPerson) {
return {
userId: data.Response[2].UserPerson.id,
displayName: data.Response[2].UserPerson.display_name,
sessionToken: data.Response[1].Token.token,
flow: "api-key",
};
}
throw new Error(
"UserApiKey and UserPerson is missing. First is expected in OAuth flow, second in API Key flow.",
);
}
async makeSignedRequest<T>(endpoint: string, method: string = "GET", body?: object): Promise<T> {
if (!this.#retrievedToken) {
throw new Error("Failed to initialize bunq context");
}
const bodyStr = body ? JSON.stringify(body) : "";
const signature = await signRequestBody(bodyStr);
const headers: Record<string, string> = {
"Content-Type": "application/json",
"X-Bunq-Client-Authentication": this.#retrievedToken.sessionToken,
"X-Bunq-Client-Signature": signature,
};
const response = await fetch(`https://api.bunq.com/v1${endpoint}`, {
method,
headers,
body: bodyStr || undefined,
});
if (!response.ok) {
throw new Error(`Bunq API request failed: ${await response.text()}`);
}
return (await response.json()) as T;
}
}