Hono Netlify Adapter not working out of the box + Solution

[pkorac]

What's wrong? How to reproduce the bug?

When using the npm create hono@latest command to create an app for deployment to Netlify, the app doesn’t build properly.

Running netlify dev results in a series of errors:

◈ Failed to run Edge Function index:
TypeError: Import 'https://registry-staging.deno.com/@hono/hono/meta.json' failed: error sending request for url (https://registry-staging.deno.com/@hono/hono/meta.json): error trying to connect: dns error: failed to lookup address information: nodename nor servname provided, or not known
    at file:///Users/peter/Documents/explorations/hononetlify/netlify/edge-functions/index.ts:1:22
    at async file:///Users/peter/Documents/explorations/hononetlify/.netlify/edge-functions-serve/dev.js:7:35 {
  code: "ERR_MODULE_NOT_FOUND"
}
TypeError: Import 'https://registry-staging.deno.com/@hono/hono/meta.json' failed: error sending request for url (https://registry-staging.deno.com/@hono/hono/meta.json): error trying to connect: dns error: failed to lookup address information: nodename nor servname provided, or not known
    at file:///Users/peter/Documents/explorations/hononetlify/netlify/edge-functions/index.ts:1:22
    at async file:///Users/peter/.nvm/versions/node/v22.4.1/lib/node_modules/netlify-cli/node_modules/@netlify/edge-bundler/deno/config.ts:12:10 {
  code: "ERR_MODULE_NOT_FOUND"
}

What version of Hono are you using?

4.3.11

What runtime/platform is your app running on? (with version if possible)

Netlify

Solution (what worked for me)

Use the URL method of importing packages instead of jsr.

Replace the

import { Hono } from 'jsr:@hono/hono'
import { handle } from 'jsr:@hono/hono/netlify'

with

import { Hono } from "https://deno.land/x/hono@v4.3.11/mod.ts";
import { handle } from "https://deno.land/x/hono@v4.3.11/adapter/netlify/index.ts";

Or with

import { Hono } from "https://esm.sh/jsr/@hono/hono@4";
import { handle } from "https://esm.sh/jsr/@hono/hono/netlify";

Hope this helps

What is the expected behavior?

◈ Static server listening to 3999

   ┌─────────────────────────────────────────────────┐
   │                                                 │
   │   ◈ Server now ready on http://localhost:8888   │
   │                                                 │
   └─────────────────────────────────────────────────┘

◈ Loaded edge function index

What do you see instead?

◈ Failed to run Edge Function index:
TypeError: Import 'https://registry-staging.deno.com/@hono/hono/meta.json' failed: error sending request for url (https://registry-staging.deno.com/@hono/hono/meta.json): error trying to connect: dns error: failed to lookup address information: nodename nor servname provided, or not known
    at file:///Users/peter/Documents/explorations/hononetlify/netlify/edge-functions/index.ts:1:22
    at async file:///Users/peter/Documents/explorations/hononetlify/.netlify/edge-functions-serve/dev.js:7:35 {
  code: "ERR_MODULE_NOT_FOUND"
}
TypeError: Import 'https://registry-staging.deno.com/@hono/hono/meta.json' failed: error sending request for url (https://registry-staging.deno.com/@hono/hono/meta.json): error trying to connect: dns error: failed to lookup address information: nodename nor servname provided, or not known
    at file:///Users/peter/Documents/explorations/hononetlify/netlify/edge-functions/index.ts:1:22
    at async file:///Users/peter/.nvm/versions/node/v22.4.1/lib/node_modules/netlify-cli/node_modules/@netlify/edge-bundler/deno/config.ts:12:10 {
  code: "ERR_MODULE_NOT_FOUND"
}

Additional information

I solved my issue by using one of the url importing methods https://deno.land/x/hono, there are others like esm https://esm.sh/jsr/@hono/hono@4, and perhaps the create command + example could show one of them.
Appreciate this is specific to deploying on Netlify, but that's what the create template using Netlify suggest user would be able to do.

[yusukebe]

@pkorac

Hmm. Before working on this problem, the basic Netlify app does not work correctly. Accessing GET / shows 404, and edge functions are not triggered. It may be my environment is bad, but I can't reproduce the issue 😢

[pkorac]

@yusukebe here's what my index.ts looks like:

import { Hono } from "https://esm.sh/jsr/@hono/hono@4";
import { handle } from "https://esm.sh/jsr/@hono/hono/netlify";


const app = new Hono();

app.get("/", (c) => {
	return c.text("Hello Hono!");
});

export default handle(app);

and here's my toml file

[[edge_functions]]
  function = "index"
  path = "/*"

running netlify dev compiles everything and gets it up and running

[yusukebe]

@pkorac

Thank you for the instruction. But if I ran the netlify dev command, the Next.js (!) starts and fails.

I also added the framework = "#static" to the netlify.toml, but it returned 404; Hono app was not triggered 🤷

[[edge_functions]]
  function = "index"
  path = "/*"
[dev]
  framework = "#static"

[pkorac]

@yusukebe does the starter template compile for you – the one you create with npm create hono@latest

If it doesn't. And it doesn't after you've replaced the

import { Hono } from 'jsr:@hono/hono'
import { handle } from 'jsr:@hono/hono/netlify'

with

import { Hono } from "https://deno.land/x/hono@v4.3.11/mod.ts";
import { handle } from "https://deno.land/x/hono@v4.3.11/adapter/netlify/index.ts";

Then it must me something in your configuriation/system.

[yusukebe]

@pkorac

Hmm. It's the same if I change the import statements you showed.