feat(ssg): introduce disableSSG and onlySSG

deno_dist/helper/ssg/index.ts

@@ -7,6 +7,9 @@ import { bufferToString } from '../../utils/buffer.ts'
 import { getExtension } from '../../utils/mime.ts'
 import { joinPaths, dirname } from './utils.ts'
 
+export const X_HONO_SSG_HEADER_KEY = 'x-hono-ssg'
+export const X_HONO_DISABLE_SSG_HEADER_KEY = 'x-hono-disable-ssg'
+
 /**
  * @experimental
  * `FileSystemModule` is an experimental feature.
@@ -128,6 +131,7 @@ export const fetchRoutesContent = async <
     const thisRouteBaseURL = new URL(route.path, baseURL).toString()
 
     let forGetInfoURLRequest = new Request(thisRouteBaseURL) as AddedSSGDataRequest
+    forGetInfoURLRequest.headers.set(X_HONO_SSG_HEADER_KEY, 'true')
     if (beforeRequestHook) {
       const maybeRequest = beforeRequestHook(forGetInfoURLRequest)
       if (!maybeRequest) {
@@ -147,6 +151,9 @@ export const fetchRoutesContent = async <
     for (const param of forGetInfoURLRequest.ssgParams) {
       const replacedUrlParam = replaceUrlParam(route.path, param)
       let response = await app.request(replacedUrlParam, forGetInfoURLRequest)
+      if (response.headers.get(X_HONO_DISABLE_SSG_HEADER_KEY)) {
+        continue
+      }
       if (afterResponseHook) {
         const maybeResponse = afterResponseHook(response)
         if (!maybeResponse) {
@@ -251,3 +258,29 @@ export const toSSG: ToSSGInterface = async (app, fs, options) => {
   await options?.afterGenerateHook?.(result)
   return result
 }
+
+/**
+ * @experimental
+ * `disableSSG` is an experimental feature.
+ * The API might be changed.
+ */
+
+export const disableSSG = (): MiddlewareHandler =>
+  async function disableSSG(c, next) {
+    await next()
+    c.header(X_HONO_DISABLE_SSG_HEADER_KEY, 'true')
+  }
+
+/**
+ * @experimental
+ * `onlySSG` is an experimental feature.
+ * The API might be changed.
+ */
+export const onlySSG = (): MiddlewareHandler =>
+  async function onlySSG(c, next) {
+    const headerValue = c.req.raw.headers.get(X_HONO_SSG_HEADER_KEY)
+    if (headerValue) {
+      await next()
+    }
+    return c.notFound()
+  }

src/helper/ssg/index.test.tsx

@@ -3,7 +3,14 @@ import { Hono } from '../../hono'
 // eslint-disable-next-line @typescript-eslint/no-unused-vars
 import { jsx } from '../../jsx'
 import { poweredBy } from '../../middleware/powered-by'
-import { fetchRoutesContent, saveContentToFiles, ssgParams, toSSG } from './index'
+import {
+  fetchRoutesContent,
+  saveContentToFiles,
+  ssgParams,
+  toSSG,
+  disableSSG,
+  onlySSG,
+} from './index'
 import type {
   BeforeRequestHook,
   AfterResponseHook,
@@ -321,3 +328,22 @@ describe('Dynamic route handling', () => {
     expect(htmlMap.has('/foo:bar')).toBeTruthy()
   })
 })
+
+describe('disableSSG/onlySSG middlewares', () => {
+  const app = new Hono()
+  app.get('/', (c) => c.html(<h1>Hello</h1>))
+  app.get('/api', disableSSG(), (c) => c.text('an-api'))
+  app.get('/static-page', onlySSG(), (c) => c.html(<h1>Welcome to my site</h1>))
+
+  it('Should not generate the page if disableSSG is set', async () => {
+    const htmlMap = await fetchRoutesContent(app)
+    expect(htmlMap.has('/')).toBe(true)
+    expect(htmlMap.has('/static-page')).toBe(true)
+    expect(htmlMap.has('/api')).toBe(false)
+  })
+
+  it('Should return 404 response if onlySSG() is set', async () => {
+    const res = await app.request('/static-page')
+    expect(res.status).toBe(404)
+  })
+})

src/helper/ssg/index.ts

@@ -7,6 +7,9 @@ import { bufferToString } from '../../utils/buffer'
 import { getExtension } from '../../utils/mime'
 import { joinPaths, dirname } from './utils'
 
+export const X_HONO_SSG_HEADER_KEY = 'x-hono-ssg'
+export const X_HONO_DISABLE_SSG_HEADER_KEY = 'x-hono-disable-ssg'
+
 /**
  * @experimental
  * `FileSystemModule` is an experimental feature.
@@ -128,6 +131,7 @@ export const fetchRoutesContent = async <
     const thisRouteBaseURL = new URL(route.path, baseURL).toString()
 
     let forGetInfoURLRequest = new Request(thisRouteBaseURL) as AddedSSGDataRequest
+    forGetInfoURLRequest.headers.set(X_HONO_SSG_HEADER_KEY, 'true')
     if (beforeRequestHook) {
       const maybeRequest = beforeRequestHook(forGetInfoURLRequest)
       if (!maybeRequest) {
@@ -147,6 +151,9 @@ export const fetchRoutesContent = async <
     for (const param of forGetInfoURLRequest.ssgParams) {
       const replacedUrlParam = replaceUrlParam(route.path, param)
       let response = await app.request(replacedUrlParam, forGetInfoURLRequest)
+      if (response.headers.get(X_HONO_DISABLE_SSG_HEADER_KEY)) {
+        continue
+      }
       if (afterResponseHook) {
         const maybeResponse = afterResponseHook(response)
         if (!maybeResponse) {
@@ -251,3 +258,29 @@ export const toSSG: ToSSGInterface = async (app, fs, options) => {
   await options?.afterGenerateHook?.(result)
   return result
 }
+
+/**
+ * @experimental
+ * `disableSSG` is an experimental feature.
+ * The API might be changed.
+ */
+
+export const disableSSG = (): MiddlewareHandler =>
+  async function disableSSG(c, next) {
+    await next()
+    c.header(X_HONO_DISABLE_SSG_HEADER_KEY, 'true')
+  }
+
+/**
+ * @experimental
+ * `onlySSG` is an experimental feature.
+ * The API might be changed.
+ */
+export const onlySSG = (): MiddlewareHandler =>
+  async function onlySSG(c, next) {
+    const headerValue = c.req.raw.headers.get(X_HONO_SSG_HEADER_KEY)
+    if (headerValue) {
+      await next()
+    }
+    return c.notFound()
+  }