Added new issue by email modal window

app/assets/stylesheets/pages/issues.scss

@@ -91,3 +91,20 @@ form.edit-issue {
 .issue-form .select2-container {
   width: 250px !important;
 }
+
+.issues-footer {
+  padding-top: $gl-padding;
+  padding-bottom: 37px;
+}
+
+.issue-email-modal-btn {
+  padding: 0;
+  color: $gl-link-color;
+  background-color: transparent;
+  border: 0;
+  outline: 0;
+
+  &:hover {
+    text-decoration: underline;
+  }
+}

app/models/project.rb

@@ -529,7 +529,7 @@ class Project < ActiveRecord::Base
   end
 
   def new_issue_address(author)
-    if Gitlab::IncomingEmail.enabled?
+    if Gitlab::IncomingEmail.enabled? && author
       Gitlab::IncomingEmail.reply_address(
         "#{path_with_namespace}+#{author.authentication_token}")
     end

app/views/projects/issues/_issue_by_email.html.haml

+#issue-email-modal.modal.fade{ tabindex: "-1", role: "dialog" }
+  .modal-dialog{ role: "document" }
+    .modal-content
+      .modal-header
+        %button.close{ type: "button", data: { dismiss: "modal" }, aria: { label: "close" } }
+          %span{ aria: { hidden: "true" } }= icon("times")
+        %h4.modal-title
+          Create new issue by email
+      .modal-body
+        %p
+          Write an email to
+          = succeed "." do
+            %a{ href: "mailto:#{email}" }= email
+          (This is a private email address, so keep it secret.)
+        %p
+          Send an email to this address to create an issue.
+        %p
+          Use the subject line as the title of your issue.
+        %p
+          Use the message as the body of your issue (feel free to include some nice markdown).

app/views/projects/issues/index.html.haml

 - @no_container = true
 - page_title "Issues"
+- new_issue_email = @project.new_issue_address(current_user)
 = render "projects/issues/head"
 
 = content_for :meta_tags do
@@ -24,3 +25,8 @@
 
   .issues-holder
     = render "issues"
+  - if new_issue_email
+    .issues-footer.text-center
+      %button.issue-email-modal-btn{ type: "button", data: { toggle: "modal", target: "#issue-email-modal" } }
+        Email a new issue to this project
+    = render "issue_by_email", email: new_issue_email