FEATURE: allow themes to live in private git repos

This feature allows themes sourced from git to live on private
servers, it automatically generates key pairs.

Gemfile

@@ -178,6 +178,8 @@ gem 'sassc', require: false
 gem 'rotp'
 gem 'rqrcode'
 
+gem 'sshkey', require: false
+
 if ENV["IMPORT"] == "1"
   gem 'mysql2'
   gem 'redcarpet'

Gemfile.lock

@@ -372,6 +372,7 @@ GEM
       actionpack (>= 4.0)
       activesupport (>= 4.0)
       sprockets (>= 3.0.0)
+    sshkey (1.9.0)
     stackprof (0.2.10)
     thor (0.19.4)
     thread_safe (0.3.6)
@@ -497,6 +498,7 @@ DEPENDENCIES
   shoulda
   sidekiq
   sprockets-rails
+  sshkey
   stackprof
   thor
   tilt

app/assets/javascripts/admin/controllers/modals/admin-import-theme.js.es6

@@ -1,6 +1,7 @@
 import ModalFunctionality from 'discourse/mixins/modal-functionality';
 import { ajax } from 'discourse/lib/ajax';
 import { popupAjaxError } from 'discourse/lib/ajax-error';
+import { observes } from 'ember-addons/ember-computed-decorators';
 
 export default Ember.Controller.extend(ModalFunctionality, {
   local: Ember.computed.equal('selection', 'local'),
@@ -9,6 +10,25 @@ export default Ember.Controller.extend(ModalFunctionality, {
   adminCustomizeThemes: Ember.inject.controller(),
   loading: false,
 
+  checkPrivate: Ember.computed.match('uploadUrl', /^git/),
+
+  @observes('privateChecked')
+  privateWasChecked() {
+    const checked = this.get('privateChecked');
+    if (checked && !this._keyLoading) {
+      this._keyLoading = true;
+      ajax('/admin/themes/generate_key_pair', {method: 'POST'})
+        .then(pair => {
+          this.set('privateKey', pair.private_key);
+          this.set('publicKey', pair.public_key);
+        })
+        .catch(popupAjaxError)
+        .finally(()=>{
+          this._keyLoading = false;
+        });
+    }
+  },
+
   actions: {
     importTheme() {
 
@@ -22,7 +42,13 @@ export default Ember.Controller.extend(ModalFunctionality, {
         options.data = new FormData();
         options.data.append('theme', $('#file-input')[0].files[0]);
       } else {
-        options.data = {remote: this.get('uploadUrl')};
+        options.data = {
+          remote: this.get('uploadUrl')
+        };
+
+        if (this.get('privateChecked')){
+          options.data.private_key = this.get('privateKey');
+        }
       }
 
       this.set('loading', true);
@@ -30,7 +56,13 @@ export default Ember.Controller.extend(ModalFunctionality, {
         const theme = this.store.createRecord('theme',result.theme);
         this.get('adminCustomizeThemes').send('addTheme', theme);
         this.send('closeModal');
-      }).catch(popupAjaxError).finally(() => this.set('loading', false));
+      })
+      .then(()=>{
+        this.set('privateKey', null);
+        this.set('publicKey', null);
+      })
+      .catch(popupAjaxError)
+      .finally(() => this.set('loading', false));
 
     }
   }

app/assets/javascripts/admin/templates/modal/admin-import-theme.hbs

@@ -16,7 +16,24 @@
       <div class="inputs">
         {{input value=uploadUrl placeholder="https://github.com/discourse/discourse/sample_theme"}}
         <span class="description">{{i18n 'admin.customize.theme.import_web_tip'}}</span>
+        {{#if checkPrivate}}
+          <div class='check-private'>
+          <label>
+            {{input type="checkbox" checked=privateChecked}}
+            {{i18n 'admin.customize.theme.is_private'}}
+          </label>
+          {{#if privateChecked}}
+          {{#if publicKey}}
+          <div class='public-key'>
+            {{i18n 'admin.customize.theme.public_key'}}
+            {{textarea disabled=true value=publicKey}}
+          </div>
+          {{/if}}
+          {{/if}}
+          </div>
+        {{/if}}
       </div>
+
     {{/if}}
   </div>
 {{/d-modal-body}}

app/assets/stylesheets/common/admin/customize.scss

@@ -239,3 +239,23 @@
 #custom_emoji {
   width: 27%;
 }
+
+.modal-body .inputs .check-private {
+  margin-top: 10px;
+  label {
+    padding-left: 0;
+  }
+  label input {
+    width: auto;
+    margin: 3px 0;
+  }
+
+  .public-key {
+    margin-top: 10px;
+    textarea {
+      cursor: auto;
+      height: 150px;
+    }
+  }
+}
+

app/controllers/admin/themes_controller.rb

@@ -27,6 +27,16 @@ class Admin::ThemesController < Admin::AdminController
     end
   end
 
+  def generate_key_pair
+    require 'sshkey'
+    k = SSHKey.generate
+
+    render json: {
+      private_key: k.private_key,
+      public_key: k.ssh_public_key
+    }
+  end
+
   def import
     @theme = nil
     if params[:theme]
@@ -66,8 +76,12 @@ class Admin::ThemesController < Admin::AdminController
         render json: @theme.errors, status: :unprocessable_entity
       end
     elsif params[:remote]
-      @theme = RemoteTheme.import_theme(params[:remote])
-      render json: @theme, status: :created
+      begin
+        @theme = RemoteTheme.import_theme(params[:remote], current_user, private_key: params[:private_key])
+        render json: @theme, status: :created
+      rescue RuntimeError
+        render_json_error I18n.t('errors.theme.other')
+      end
     else
       render json: @theme.errors, status: :unprocessable_entity
     end

app/models/remote_theme.rb

@@ -7,8 +7,8 @@ class RemoteTheme < ActiveRecord::Base
 
   has_one :theme
 
-  def self.import_theme(url, user = Discourse.system_user)
-    importer = GitImporter.new(url)
+  def self.import_theme(url, user = Discourse.system_user, private_key: nil)
+    importer = GitImporter.new(url, private_key: private_key)
     importer.import!
 
     theme_info = JSON.parse(importer["about.json"])
@@ -17,6 +17,7 @@ class RemoteTheme < ActiveRecord::Base
     remote_theme = new
     theme.remote_theme = remote_theme
 
+    remote_theme.private_key = private_key
     remote_theme.remote_url = importer.url
     remote_theme.update_from_remote(importer)
 
@@ -31,7 +32,7 @@ class RemoteTheme < ActiveRecord::Base
   end
 
   def update_remote_version
-    importer = GitImporter.new(remote_url)
+    importer = GitImporter.new(remote_url, private_key: private_key)
     importer.import!
     self.updated_at = Time.zone.now
     self.remote_version, self.commits_behind = importer.commits_since(remote_version)
@@ -43,7 +44,7 @@ class RemoteTheme < ActiveRecord::Base
 
     unless importer
       cleanup = true
-      importer = GitImporter.new(remote_url)
+      importer = GitImporter.new(remote_url, private_key: private_key)
       importer.import!
     end
 
@@ -162,4 +163,5 @@ end
 #  remote_updated_at :datetime
 #  created_at        :datetime         not null
 #  updated_at        :datetime         not null
+#  private_key       :text
 #

config/locales/client.en.yml

@@ -3068,6 +3068,8 @@ en:
           delete_upload_confirm: "Delete this upload? (Theme CSS may stop working!)"
           import_web_tip: "Repository containing theme"
           import_file_tip: ".dcstyle.json file containing theme"
+          is_private: "Theme is in a private git repository"
+          public_key: "Grant the following public key access to the repo:"
           about_theme: "About Theme"
           license: "License"
           component_of: "Theme is a component of:"

config/locales/server.en.yml

@@ -151,6 +151,8 @@ en:
         other: ! '%{count} errors prohibited this %{model} from being saved'
     embed:
       load_from_remote: "There was an error loading that post."
+    theme:
+      other: "Error cloning git repository, access is denied or repository is not found"
     site_settings:
       min_username_length_exists: "You cannot set the minimum username length above the shortest username."
       min_username_length_range: "You cannot set the minimum above the maximum."

config/routes.rb

@@ -201,6 +201,7 @@ Discourse::Application.routes.draw do
 
     post "themes/import" => "themes#import"
     post "themes/upload_asset" => "themes#upload_asset"
+    post "themes/generate_key_pair" => "themes#generate_key_pair"
     get "themes/:id/preview" => "themes#preview"
 
     scope "/customize", constraints: AdminConstraint.new do

db/migrate/20180309014014_add_private_key_to_remote_theme.rb

@@ -0,0 +1,5 @@
+class AddPrivateKeyToRemoteTheme < ActiveRecord::Migration[5.1]
+  def change
+    add_column :remote_themes, :private_key, :text
+  end
+end

lib/git_importer.rb

@@ -2,16 +2,21 @@ class GitImporter
 
   attr_reader :url
 
-  def initialize(url)
+  def initialize(url, private_key: nil)
     @url = url
     if @url.start_with?("https://github.com") && !@url.end_with?(".git")
       @url += ".git"
     end
     @temp_folder = "#{Pathname.new(Dir.tmpdir).realpath}/discourse_theme_#{SecureRandom.hex}"
+    @private_key = private_key
   end
 
   def import!
-    Discourse::Utils.execute_command("git", "clone", @url, @temp_folder)
+    if @private_key
+      import_private!
+    else
+      import_public!
+    end
   end
 
   def commits_since(hash)
@@ -55,4 +60,26 @@ class GitImporter
     File.read(fullpath)
   end
 
+  protected
+
+  def import_public!
+    Discourse::Utils.execute_command("git", "clone", @url, @temp_folder)
+  end
+
+  def import_private!
+    ssh_folder = "#{Pathname.new(Dir.tmpdir).realpath}/discourse_theme_ssh_#{SecureRandom.hex}"
+    FileUtils.mkdir_p ssh_folder
+
+    Dir.chdir(ssh_folder) do
+      File.write('id_rsa', @private_key.strip)
+      FileUtils.chmod(0600, 'id_rsa')
+    end
+
+    Discourse::Utils.execute_command({
+      'GIT_SSH_COMMAND' => "ssh -i #{ssh_folder}/id_rsa"
+    }, "git", "clone", @url, @temp_folder)
+  ensure
+    FileUtils.rm_rf ssh_folder
+  end
+
 end

spec/controllers/admin/themes_controller_spec.rb

@@ -12,6 +12,15 @@ describe Admin::ThemesController do
       @user = log_in(:admin)
     end
 
+    context '.generate_key_pair' do
+      it 'can generate key pairs' do
+        post :generate_key_pair, format: :json
+        json = JSON.parse(response.body)
+        expect(json["private_key"]).to include("RSA PRIVATE KEY")
+        expect(json["public_key"]).to include("ssh-rsa ")
+      end
+    end
+
     context '.upload_asset' do
       render_views