I have the following front end middleware:

export class FrontendMiddleware implements NestMiddleware {
    use(req: any, res: any, next: () => void) {
        const url = req.originalUrl;
        if (url.indexOf('rest') === 1) {
            next();
        } else if (allowedExt.filter(ext => url.indexOf(ext) > 0).length > 0) {
            res.sendFile(resolvePath(url));
        } else {
            res.sendFile(resolvePath('index.html'));
        }
    }
} 

It works fine with express, but with fastify, res.sendFile is undefined, so how can I fix that?

I have the following front end middleware:

export class FrontendMiddleware implements NestMiddleware {
    use(req: any, res: any, next: () => void) {
        const url = req.originalUrl;
        if (url.indexOf('rest') === 1) {
            next();
        } else if (allowedExt.filter(ext => url.indexOf(ext) > 0).length > 0) {
            res.sendFile(resolvePath(url));
        } else {
            res.sendFile(resolvePath('index.html'));
        }
    }
} 

It works fine with express, but with fastify, res.sendFile is undefined, so how can I fix that?

• javascript
• node.js
• typescript
• nestjs
• fastify

• Oh, didn't work for you after all or why did you unaccept? – Kim Kern Commented Apr 28, 2019 at 9:55
• reply.type is undefined either – yantrab Commented Apr 28, 2019 at 19:49
• Did you use res.type? – Kim Kern Commented Apr 28, 2019 at 19:52

4 Answers 4

Have a look at this issue. sendFile has no equivalent method in fastify; you have to do it manually:

const stream = fs.createReadStream(resolvePath('index.html'))
res.type('text/html').send(stream)

You can also store index.html in memory and send it from it:

const bufferIndexHtml = fs.readFileSync('index.html')
res.type('text/html').send(bufferIndexHtml)

An alternative method is to use the fastify-static module provided by Fastify. They have some good examples for sending a file. More information can be found about it here - https://github.com/fastify/fastify-static

Here's an example of sending a file -

const fastify = require('fastify')({logger: true})
const path = require('path')

fastify.register(require('@fastify/static'), {
  root: path.join(__dirname, 'public'),
  prefix: '/public/', // optional: default '/'
})

fastify.get('/sendHtmlFile', function (req, reply) {
  reply.sendFile('myHtml.html') // serving path.join(__dirname, 'public', 'myHtml.html') directly
})

// Run the server!
fastify.listen({ port: 3000 }, (err, address) => {
  if (err) throw err
  // Server is now listening on ${address}
})

If you use TypeScript, declare it like:

import fastifyStatic from "@fastify/static";
export const server = fastify({
  logger: true,
});

server.register(fastifyStatic, {
  root: path.join(__dirname, "/.testdata/uploads"),
  //prefix: "/public/", // optional: default '/'
  //constraints: { host: "example.com" }, // optional: default {}
});

Functions/types like sendFile will be found.