fastify · Eomm · Oct 31, 2019 · Oct 7, 2019 · Oct 8, 2019 · Oct 14, 2019
diff --git a/README.md b/README.md
@@ -144,6 +144,20 @@ To use partials in handlebars you will need to pass the names and paths in the o
   }
 ```
 
+To use layouts in handlebars you will need to pass the `layout` parameter:
+```js
+fastify.register(require('point-of-view'), {  
+  engine: {  
+    handlebars: require('handlebars')  
+  },
+  layout: './templates/layout.hbs'
+});  
+
+fastify.get('/', (req, reply) => {  
+  reply.view('./templates/index.hbs', { text: 'text' })  
+})  
+```
+
 To configure nunjunks environment after initialisation, you can pass callback function to options:
 ```js
   options: {

diff --git a/index.js b/index.js
@@ -2,6 +2,7 @@
 
 const fp = require('fastify-plugin')
 const readFile = require('fs').readFile
+const accessSync = require('fs').accessSync
 const resolve = require('path').resolve
 const join = require('path').join
 const HLRU = require('hashlru')
@@ -27,10 +28,22 @@ function fastifyView (fastify, opts, next) {
   const includeViewExtension = opts.includeViewExtension || false
   const prod = typeof opts.production === 'boolean' ? opts.production : process.env.NODE_ENV === 'production'
   const defaultCtx = opts.defaultContext || {}
+  const layoutFileName = opts.layout
+
+  if (layoutFileName && type !== 'handlebars') {
+    next(new Error('"layout" option only available for handlebars engine'))
+    return
+  }
+
+  if (layoutFileName && !hasAccessToLayoutFile(layoutFileName)) {
+    next(new Error(`unable to access template "${layoutFileName}"`))
+    return
+  }
+
   const renders = {
     marko: viewMarko,
     'ejs-mate': viewEjsMate,
-    handlebars: viewHandlebars,
+    handlebars: withLayout(viewHandlebars),
     mustache: viewMustache,
     nunjucks: viewNunjucks,
     'art-template': viewArtTemplate,
@@ -398,6 +411,40 @@ function fastifyView (fastify, opts, next) {
   } else {
     next()
   }
+
+  function withLayout (render) {
+    if (layoutFileName) {
+      return function (page, data, opts) {
+        const that = this
+
+        render.call({
+          getHeader: () => {},
+          header: () => {},
+          send: (result) => {
+            if (result instanceof Error) {
+              throw result
+            }
+
+            data = Object.assign(data, { body: result })
+
+            render.call(that, layoutFileName, data, opts)
+          }
+        }, page, data, opts)
+      }
+    }
+
+    return render
+  }
+
+  function hasAccessToLayoutFile (fileName) {
+    try {
+      accessSync(join(templatesDir, getPage(fileName, 'hbs')))
+
+      return true
+    } catch (e) {
+      return false
+    }
+  }
 }
 
 module.exports = fp(fastifyView, { fastify: '^2.x' })
diff --git a/templates/index-for-layout.hbs b/templates/index-for-layout.hbs
@@ -0,0 +1 @@
+<p>{{text}}</p>
diff --git a/templates/layout.hbs b/templates/layout.hbs
@@ -0,0 +1,7 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head></head>
+  <body>
+    {{{body}}}
+  </body>
+</html>
diff --git a/test/test-handlebars.js b/test/test-handlebars.js
@@ -181,6 +181,31 @@ test('fastify.view with handlebars engine with callback and html-minifier', t =>
   })
 })
 
+test('fastify.view with handlebars engine with layout option', t => {
+  t.plan(3)
+
+  const fastify = Fastify()
+  const handlebars = require('handlebars')
+  const data = { text: 'it works!' }
+
+  fastify.register(require('../index'), {
+    engine: {
+      handlebars
+    },
+    layout: './templates/layout.hbs'
+  })
+
+  fastify.ready(err => {
+    t.error(err)
+
+    fastify.view('./templates/index-for-layout.hbs', data, (err, compiled) => {
+      t.error(err)
+      t.strictEqual(handlebars.compile(fs.readFileSync('./templates/index.hbs', 'utf8'))(data), compiled)
+      fastify.close()
+    })
+  })
+})
+
 test('reply.view with handlebars engine', t => {
   t.plan(6)
   const fastify = Fastify()
@@ -519,3 +544,36 @@ test('reply.view with handlebars engine with partials', t => {
     })
   })
 })
+
+test('reply.view with handlebars engine with layout option', t => {
+  t.plan(6)
+  const fastify = Fastify()
+  const handlebars = require('handlebars')
+  const data = { text: 'text' }
+
+  fastify.register(require('../index'), {
+    engine: {
+      handlebars: handlebars
+    },
+    layout: './templates/layout.hbs'
+  })
+
+  fastify.get('/', (req, reply) => {
+    reply.view('./templates/index-for-layout.hbs', data)
+  })
+
+  fastify.listen(0, err => {
+    t.error(err)
+    sget({
+      method: 'GET',
+      url: 'http://localhost:' + fastify.server.address().port
+    }, (err, response, replyBody) => {
+      t.error(err)
+      t.strictEqual(response.statusCode, 200)
+      t.strictEqual(response.headers['content-length'], '' + replyBody.length)
+      t.strictEqual(response.headers['content-type'], 'text/html; charset=utf-8')
+      t.strictEqual(handlebars.compile(fs.readFileSync('./templates/index.hbs', 'utf8'))(data), replyBody.toString())
+      fastify.close()
+    })
+  })
+})
diff --git a/test/test.js b/test/test.js
@@ -107,3 +107,33 @@ test('register callback should throw if the engine is not supported', t => {
     t.is(err.message, '\'notSupported\' not yet supported, PR? :)')
   })
 })
+
+test('register callback with handlebars engine should throw if layout file does not exist', t => {
+  t.plan(2)
+  const fastify = Fastify()
+
+  fastify.register(require('../index'), {
+    engine: {
+      handlebars: require('handlebars')
+    },
+    layout: './templates/does-not-exist.hbs'
+  }).ready(err => {
+    t.ok(err instanceof Error)
+    t.deepEqual('unable to access template "./templates/does-not-exist.hbs"', err.message)
+  })
+})
+
+test('register callback should throw if layout option is provided and engine is not handlebars', t => {
+  t.plan(2)
+  const fastify = Fastify()
+
+  fastify.register(require('../index'), {
+    engine: {
+      ejs: require('ejs')
+    },
+    layout: './templates/layout.hbs'
+  }).ready(err => {
+    t.ok(err instanceof Error)
+    t.deepEqual('"layout" option only available for handlebars engine', err.message)
+  })
+})