Adapter Helper

The Adapter Helper provides a seamless way to interact with various platforms through a unified interface.

Import

npmDeno

import { Hono } from 'hono'
import { env, getRuntimeKey } from 'hono/adapter'

import { Hono } from 'hono'
import { env, getRuntimeKey } from 'hono/adapter'

import { Hono } from 'https://deno.land/x/hono/mod.ts'
import { env, getRuntimeKey } from 'https://deno.land/x/hono/helper.ts'

import { Hono } from 'https://deno.land/x/hono/mod.ts'
import { env, getRuntimeKey } from 'https://deno.land/x/hono/helper.ts'

`env()`

The env() function facilitates retrieving environment variables across different runtimes, extending beyond just Cloudflare Workers' Bindings.

import { env } from 'hono/adapter'

app.get('/env', (c) => {
  const { NAME } = env<{ NAME: string }>(c)
  return c.text(NAME)
})

import { env } from 'hono/adapter'

app.get('/env', (c) => {
  const { NAME } = env<{ NAME: string }>(c)
  return c.text(NAME)
})

Supported Runtimes:

Cloudflare Workers
Deno
Bun
Lagon
Node.js
Vercel
AWS Lambda
Lambda@Edge

Specify the runtime

You can specify the runtime to get environment variables by passing the runtime key as the second argument.

app.get('/env', (c) => {
  const { NAME } = env<{ NAME: string }>(c, 'workerd')
  return c.text(NAME)
})

app.get('/env', (c) => {
  const { NAME } = env<{ NAME: string }>(c, 'workerd')
  return c.text(NAME)
})

`getRuntimeKey()`

The getRuntimeKey() function returns the identifier of the current runtime.

app.get('/', (c) => {
  if (getRuntimeKey() === 'workerd') {
    return c.text('You are on Cloudflare')
  } else if (getRuntimeKey() === 'bun') {
    return c.text('You are on Bun')
  }
  ...
})

app.get('/', (c) => {
  if (getRuntimeKey() === 'workerd') {
    return c.text('You are on Cloudflare')
  } else if (getRuntimeKey() === 'bun') {
    return c.text('You are on Bun')
  }
  ...
})

Available Runtimes

Here are the supported runtimes, with some being inspired by WinterCG's Runtime Keys:

node
deno
bun
workerd - Cloudflare Workers
fastly
edge-light - Vercel Edge Functions
lagon
other

Adapter Helper ​

Import ​

env() ​

Specify the runtime ​

getRuntimeKey() ​

Available Runtimes ​