fastify-line/dist/plugin.js

Fastify plugin for the LINE Messaging API

import { LINE_SIGNATURE_HTTP_HEADER_NAME, messagingApi, validateSignature } from '@line/bot-sdk';
import fp from 'fastify-plugin';
import getRawBody from 'raw-body';
import { InvalidSignatureError, MissingSignatureError } from './error.js';
const plugin = (fastify, opts, done) => {
    if (fastify.hasDecorator('line')) {
        done(new Error('fastify-line plugin has already been registered'));
        return;
    }
    const { channelSecret, channelAccessToken, skipVerify = false } = opts;
    if (!channelSecret) {
        done(new Error('"channelSecret" option is required'));
        return;
    }
    if (!channelAccessToken) {
        done(new Error('"channelAccessToken" option is required'));
        return;
    }
    const { MessagingApiClient } = messagingApi;
    const client = new MessagingApiClient({ channelAccessToken });
    fastify.decorate('line', client);
    fastify.addHook('onRoute', (routeOptions) => {
        const skip = routeOptions.method !== 'POST' || !routeOptions.config?.lineWebhook;
        if (skip)
            return;
        const existingPreParsing = routeOptions.preParsing || [];
        routeOptions.preParsing = [
            parseRawBody,
            ...(Array.isArray(existingPreParsing) ? existingPreParsing : [existingPreParsing]),
        ];
        if (!skipVerify) {
            const existingPreHandler = routeOptions.preHandler || [];
            routeOptions.preHandler = [
                verifySignature,
                ...(Array.isArray(existingPreHandler) ? existingPreHandler : [existingPreHandler]),
            ];
        }
    });
    const parseRawBody = (request, _reply, payload, done) => {
        const { bodyLimit } = request.routeOptions;
        getRawBody(payload, {
            length: null,
            limit: bodyLimit, // avoid memory leak
            encoding: 'utf8', // ensure the body is a string
        }, (err, string) => {
            if (err) {
                /**
                 * the error is managed by fastify server
                 */
                return;
            }
            request.rawBody = string;
        });
        done(null, payload);
    };
    const verifySignature = (request, _reply, done) => {
        const signature = request.headers[LINE_SIGNATURE_HTTP_HEADER_NAME];
        if (!signature) {
            done(new MissingSignatureError());
            return;
        }
        if (request.rawBody && !validateSignature(request.rawBody, channelSecret, signature)) {
            done(new InvalidSignatureError(signature));
            return;
        }
        done();
    };
    done();
};
export const fastifyLine = fp(plugin, {
    name: 'fastify-line',
    fastify: '5.x',
});