[Feature] Override the serializer for json

[ShravanSunder]

What is the feature you are proposing?

It would be great to be able to easily override the serializer in req/res of c.json. I would like to use superjson to make date handling easier.

[yusukebe]

Hi @ShravanSunder

Honestly, I don't want to add more features to c.json(), even though the changes might not be big.

Instead, you can use c.render() and c.setRenderer():

https://hono.dev/api/context#render-setrenderer

[ShravanSunder]

@yusukebe Just so that i understand well, i would set my custom renderer with setRender and use that? I think that's a good fallback. Would this also work with hono stacks?

[yusukebe]

@ShravanSunder

Yes. You can write like the following though it will be a little bit verbose.

import { Hono } from 'hono'

const app = new Hono()

declare module 'hono' {
  interface ContextRenderer {
    (data: object): Response
  }
}

app.get('/api/*', async (c, next) => {
  c.setRenderer((data) => {
    return c.body(JSON.stringify(data, null, 4))
  })
  await next()
})

app.get('/api/foo', (c) => {
  return c.render({
    foo: 'bar',
  })
})

[ShravanSunder]

@yusukebe thanks!

One more question, is this method also possible to use with https://hono.dev/concepts/stacks

[yusukebe]

Ah, you want to use jsonT()?

[yusukebe]

There might be someone using superjson for RPC, but I can't recall it now. Hmm.

[ShravanSunder]

i think most specifically the handling of dates is the best thing out of superjson. Makes things uncomplicated

[jvhellemond]

FWIW: I'm going to try the same (using setRenderer() and render()) to be able to "support" Infinity and -Infinity in JSON.

[noahehall]

hmm i'm going to try this setrender pattern with msgpack

[update] worked perfectly, i'll test out the rpc stack in a bit

// @see https://github.com/honojs/hono/issues/1706
declare module "hono" {
  interface CRParams {
    data: Map<any, any>;
    as?: string;
    status: number;
  }
  interface ContextRenderer {
    (opts: CRParams): Response;
  }
}
players.get("*", async (c, next) => {
  c.setRenderer(({ data, as = "msgpack", status }) => {
    switch (as) {
      // case "typed":
      case "json":
        return c.json(toJson(data), status);
      case "string":
        return c.text(toJsonStringified(data), status);
      default:
        return new Response(encoder.encode(data, { extensionCodec }), {
          status,
          headers: {
            "Access-Control-Allow-Origin": "*",
            ...MSGPACK_HEADERS,
          },
        });
    }
  });
  await next();
});

players.get("/", async (c) => {
  // curl "localhost:3000/v1/players?as=json&pl=knoa&pl=nirvai"
  // curl "localhost:3000/v1/players?as=string&pl=knoa&pl=nirvai"
  // curl "localhost:3000/v1/players?pl=knoa&pl=nirvai"
  const { as, pl } = c.req.queries();
  return c.render({ as: as?.[0], data: await playersQuery.players(getBaseOpts({ names: pl })) });
});

[maou-shonen]

I also hope to see this feature.
Although c.render can work well,
I believe using c.json for handling JSON and c.render for handling other more complex things would be more intuitive.
It would also prevent me from accidentally using the wrong method in different repository

[musjj]

I would love to see this too. AFAIK setRenderer() can be used to deserialize the data to a superjson string, but you still need to serialize it manually on the RPC client side right?