Add protobuf layer

layers/+lang/protobuf/README.org

@@ -0,0 +1,23 @@
+#+TITLE: Protocol Buffers layer
+#+HTML_HEAD_EXTRA: <link rel="stylesheet" type="text/css" href="../../../css/readtheorg.css" />
+
+* Table of Contents                                        :TOC_4_org:noexport:
+ - [[Description][Description]]
+ - [[Features][Features]]
+ - [[Install][Install]]
+
+* Description
+Highlighting and syntax checking for [[https://developers.google.com/protocol-buffers/][Protocol Buffer]] files.
+
+Uses Google's [[https://github.com/google/protobuf/blob/master/editors/protobuf-mode.el][protobuf-mode]] with [[https://github.com/edvorg/flycheck-protobuf][flycheck-protobuf]].
+
+* Features
++ Syntax Highlighting
++ Syntax checking using Flycheck (=protoc= compiler must be available)
++ Correct Indentation and commenting
++ Quickly browse file contents using =M-x helm-imenu= and =M-x imenu=.
+
+* Install
+To use this configuration layer, add it to your =~/.spacemacs=. You will need to
+add =protobuf= to the existing =dotspacemacs-configuration-layers= list in this
+file.

layers/+lang/protobuf/packages.el

@@ -0,0 +1,28 @@
+;;; packages.el --- Protocol Buffers Layer packages File for Spacemacs
+;;
+;; Copyright (c) 2012-2016 Sylvain Benner & Contributors
+;;
+;; Author: Amol Mandhane <https://github.com/amol-mandhane>
+;; URL: https://github.com/syl20bnr/spacemacs
+;;
+;; This file is not part of GNU Emacs.
+;;
+;;; License: GPLv3
+
+(setq protobuf-packages
+      '(
+        flycheck
+        protobuf-mode
+        ))
+
+(defun protobuf/init-protobuf-mode ()
+  (use-package protobuf-mode
+    :init (progn
+            (defun spacemacs//setup-protobuf-imenu ()
+              "Setup imenu regex for protocol buffers."
+              (setq imenu-generic-expression '((nil "^[[:space:]]*\\(message\\|service\\|enum\\)[[:space:]]+\\([[:alnum:]]+\\)"
+                                                    2))))
+            (add-hook 'protobuf-mode-hook 'spacemacs//setup-protobuf-imenu))))
+
+(defun protobuf/post-init-flycheck ()
+  (spacemacs/add-flycheck-hook 'protobuf-mode))