Allow throwing responses (like Remix) and automatically wrap them in HttpException

[ajaishankar]

What is the feature you are proposing?

Having a conditional response like the following breaks type inference as a generic Response is inferred

app.get("/profile", (c) => {
  return c.var.user ? c.json(c.var.user) : c.redirect("/login");
});

Feel the documentation could be enhanced to avoid conditional responses and use HttpException instead

app.get("/profile", (c) => {
  if (!c.var.user) {
    throw new HTTPException(undefined, {
      res: c.redirect("/login"),
    });
  }
  return c.json(c.var.user);
});

Since we are throwing an exception for the redirect, the return type is inferred correctly for the happy path.

Even better maybe hono could support throwing responses similar to Remix?

https://remix.run/docs/en/main/utils/redirect
https://remix.run/docs/en/main/guides/not-found#how-to-send-a-404

app.get("/profile", (c) => {
  if (!c.var.user) {
    throw c.redirect("/login")
  }
  return c.json(c.var.user);
});

This can be achieved with a simple middleware, but feel this might be a good enhancement?

[mvares]

hey @yusukebe, could you take a look at that?

[yusukebe]

Hi @ajaishankar

One of the reasons why it occurs is the c.redirect() does not support the RPC. We can make it support it. How about like this?

const app = new Hono()

const flag = true

const routes = app.get('/profile', (c) => {
  if (!flag) {
    return c.redirect('/', 301)
  }
  return c.json({ name: 'abc' }, 200)
})

const client = hc<typeof routes>('/')

const res = await client.profile.$get()

if (res.status === 301) {
  console.log(res.headers.get('Location'))
} else {
  const data = await res.json()
  //    ^ { name: string }
}

[mvares]

Will Hono implement this soon?

[yusukebe]

@molives yes.

@ajaishankar Can you check #2908?

[ajaishankar]

@yusukebe

Commented on the PR, looks good...

Redirect is a common enough use case and nice to have support for this in hono RPC.

For something like Remix thrown response I'd suggested very easy to accomplish with a simple middleware. Again Hono makes everything super simple! 🙂

const thrownResponseToHttpException = createMiddleware(async (c, next) => {
  try {
    await next();
  } catch (e) {
    throw e instanceof Response ? new HTTPException(undefined, { res: e }) : e;
  }
});

[yusukebe]

Hi @ajaishankar

Is this issue solved?

[ajaishankar]

Yes, no need to add this to Hono since it can be accomplished with a middleware..