Merge branch '1480-export-issues-csv' into 'master'

Export issues to CSV

Closes #1480

See merge request !1126

app/assets/javascripts/issues/export_csv_modal.js

+/* eslint-disable no-new */
+
+$(() => {
+  class ExportCSVModal {
+    constructor() {
+      this.$modal = $('.issues-export-modal');
+      this.$downloadBtn = $('.csv_download_link');
+      this.$closeBtn = $('.modal-header .close');
+      this.init();
+    }
+
+    init() {
+      this.$modal.modal({ show: false });
+      this.$downloadBtn.on('click', () => this.$modal.modal('show'));
+      this.$closeBtn.on('click', () => this.$modal.modal('hide'));
+    }
+  }
+
+  new ExportCSVModal();
+});

app/assets/javascripts/issues/issues_bundle.js

+require('./export_csv_modal');

app/assets/stylesheets/pages/issues.scss

@@ -129,6 +129,21 @@ ul.related-merge-requests > li {
   padding-bottom: 37px;
 }
 
+.issues-export-modal {
+  .export-svg-container {
+    height: 56px;
+    padding: 10px 10px 0;
+  }
+
+  svg {
+    height: 100%;
+  }
+
+  .export-checkmark {
+    color: $green-light;
+  }
+}
+
 .issue-email-modal-btn {
   padding: 0;
   color: $gl-link-color;

app/controllers/projects/issues_controller.rb

@@ -6,6 +6,8 @@ class Projects::IssuesController < Projects::ApplicationController
   include IssuableCollections
   include SpammableActions
 
+  prepend_before_action :authenticate_user!, only: [:export_csv]
+
   before_action :redirect_to_external_issue_tracker, only: [:index, :new]
   before_action :module_enabled
   before_action :issue, only: [:edit, :update, :show, :referenced_merge_requests,
@@ -25,6 +27,7 @@ class Projects::IssuesController < Projects::ApplicationController
   def index
     @collection_type    = "Issue"
     @issues             = issues_collection
+
     @issues             = @issues.page(params[:page])
     @issuable_meta_data = issuable_meta_data(@issues, @collection_type)
 
@@ -142,6 +145,14 @@ class Projects::IssuesController < Projects::ApplicationController
     render_conflict_response
   end
 
+  def export_csv
+    csv_params = filter_params.permit(IssuableFinder::VALID_PARAMS)
+    ExportCsvWorker.perform_async(@current_user.id, @project.id, csv_params)
+
+    index_path = namespace_project_issues_path(@project.namespace, @project)
+    redirect_to(index_path, notice: "Your CSV export has started. It will be emailed to #{current_user.notification_email} when complete.")
+  end
+
   def referenced_merge_requests
     @merge_requests = @issue.referenced_merge_requests(current_user)
     @closed_by_merge_requests = @issue.closed_by_merge_requests(current_user)

app/finders/issuable_finder.rb

@@ -20,6 +20,7 @@
 #
 class IssuableFinder
   NONE = '0'.freeze
+  VALID_PARAMS = %i(scope state group_id project_id milestone_title assignee_id search label_name sort assignee_username author_id author_username authorized_only due_date iids non_archived weight).freeze
 
   attr_accessor :current_user, :params
 
@@ -77,7 +78,7 @@ class IssuableFinder
     counts[:all] = counts.values.sum
     counts[:opened] += counts[:reopened]
 
-    counts
+    counts.with_indifferent_access
   end
 
   def find_by!(*params)

app/helpers/issuables_helper.rb

@@ -134,10 +134,7 @@ module IssuablesHelper
 
     state_title = titles[state] || state.to_s.humanize
 
-    count =
-      Rails.cache.fetch(issuables_state_counter_cache_key(issuable_type, state), expires_in: 2.minutes) do
-        issuables_count_for_state(issuable_type, state)
-      end
+    count = cached_issuables_count_for_state(issuable_type, state)
 
     html = content_tag(:span, state_title)
     html << " " << content_tag(:span, number_with_delimiter(count), class: 'badge')
@@ -145,6 +142,12 @@ module IssuablesHelper
     html.html_safe
   end
 
+  def cached_issuables_count_for_state(issuable_type, state)
+    Rails.cache.fetch(issuables_state_counter_cache_key(issuable_type, state), expires_in: 2.minutes) do
+      issuables_count_for_state(issuable_type, state)
+    end
+  end
+
   def cached_assigned_issuables_count(assignee, issuable_type, state)
     cache_key = hexdigest(['assigned_issuables_count', assignee.id, issuable_type, state].join('-'))
     Rails.cache.fetch(cache_key, expires_in: 2.minutes) do

app/mailers/emails/csv_export.rb

+module Emails
+  module CsvExport
+    def issues_csv_email(user, project, csv_data, export_status)
+      @project = project
+      @issues_count = export_status.fetch(:rows_expected)
+      @written_count = export_status.fetch(:rows_written)
+      @truncated = export_status.fetch(:truncated)
+
+      filename = "#{project.full_path.parameterize}_issues_#{Date.today.iso8601}.csv"
+      attachments[filename] = { content: csv_data, mime_type: 'text/csv' }
+      mail(to: user.notification_email, subject: subject("Exported issues")) do |format|
+        format.html { render layout: 'mailer' }
+        format.text { render layout: 'mailer' }
+      end
+    end
+  end
+end

app/mailers/notify.rb

@@ -3,6 +3,7 @@ class Notify < BaseMailer
 
   include Emails::AdminNotification
   include Emails::Issues
+  include Emails::CsvExport
   include Emails::MergeRequests
   include Emails::Notes
   include Emails::Projects

app/models/concerns/issuable.rb

@@ -178,6 +178,14 @@ module Issuable
       end
     end
 
+    def labels_hash
+      issue_labels = Hash.new { |h, k| h[k] = [] }
+      eager_load(:labels).pluck(:id, 'labels.title').each do |issue_id, label|
+        issue_labels[issue_id] << label
+      end
+      issue_labels
+    end
+
     # Includes table keys in group by clause when sorting
     # preventing errors in postgres
     #

app/services/issues/export_csv_service.rb

+module Issues
+  class ExportCsvService
+    include Gitlab::Routing.url_helpers
+    include GitlabRoutingHelper
+
+    # Target attachment size before base64 encoding
+    TARGET_FILESIZE = 15000000
+
+    def initialize(issues_relation)
+      @issues = issues_relation
+      @labels = @issues.labels_hash
+    end
+
+    def csv_data
+      csv_builder.render(TARGET_FILESIZE)
+    end
+
+    def email(user, project)
+      Notify.issues_csv_email(user, project, csv_data, csv_builder.status).deliver_now
+    end
+
+    def csv_builder
+      @csv_builder ||=
+        CsvBuilder.new(@issues.includes(:author, :assignee), header_to_value_hash)
+    end
+
+    private
+
+    def header_to_value_hash
+      {
+       'Issue ID' => 'iid',
+       'URL' => -> (issue) { issue_url(issue) },
+       'Title' => 'title',
+       'State' => -> (issue) { issue.closed? ? 'Closed' : 'Open' },
+       'Description' => 'description',
+       'Author' => 'author_name',
+       'Author Username' => -> (issue) { issue.author&.username },
+       'Assignee' => 'assignee_name',
+       'Assignee Username' => -> (issue) { issue.assignee&.username },
+       'Confidential' => -> (issue) { issue.confidential? ? 'Yes' : 'No' },
+       'Due Date' => -> (issue) { issue.due_date&.to_s(:csv) },
+       'Created At (UTC)' => -> (issue) { issue.created_at&.to_s(:csv) },
+       'Updated At (UTC)' => -> (issue) { issue.updated_at&.to_s(:csv) },
+       'Milestone' => -> (issue) { issue.milestone&.title },
+       'Labels' => -> (issue) { @labels[issue.id].sort.join(',').presence }
+      }
+    end
+  end
+end

app/views/notify/issues_csv_email.html.haml

+%p{ style: 'font-size:18px; text-align:center;  line-height:30px;' }
+  Your CSV export of #{ pluralize(@written_count, 'issue') } from project
+  %a{ href: project_url(@project), style: "color:#3777b0; text-decoration:none; display:block;" }
+    = @project.full_name
+  has been added to this email as an attachment.
+  - if @truncated
+    %p
+      This attachment has been truncated to avoid exceeding a maximum allowed attachment size of 20MB. #{ @written_count } of #{ @issues_count } issues have been included. Consider re-exporting with a narrower selection of issues.

app/views/notify/issues_csv_email.text.erb

+Your CSV export of <%= pluralize(@written_count, 'issue') %> from project <%= @project.full_name %> (<%= project_url(@project) %>) has been added to this email as an attachment.
+
+<% if @truncated %>
+This attachment has been truncated to avoid exceeding a maximum allowed attachment size of 20MB. <%= @written_count %> of <%= @issues_count %> issues have been included. Consider re-exporting with a narrower selection of issues.
+<% end %>
\ No newline at end of file

app/views/projects/issues/export_issues/_csv_download.html.haml

+.issues-export-modal.modal
+  .modal-dialog
+    .modal-content
+      .modal-header
+        %a.close{ href: '#', 'data-dismiss' => 'modal' } ×
+        .export-svg-container.pull-right
+          = render 'projects/issues/export_issues/export_issues_list.svg'
+        %h3
+          Export issues
+      .modal-header
+        = icon('check', { class: 'export-checkmark' })
+        %strong
+          #{pluralize(cached_issuables_count_for_state(:issues, params[:state]), 'issue')} selected
+      .modal-body
+        %div
+          The CSV export will be created in the background. Once finished, it will be sent to
+          %strong= @current_user.notification_email
+          in an attachment.
+      .modal-footer
+        = link_to 'Export issues', export_csv_namespace_project_issues_path(@project.namespace, @project, params.permit(IssuableFinder::VALID_PARAMS)), method: :post, class: 'btn btn-success pull-left', title: 'Export issues'

app/views/projects/issues/export_issues/_export_issues_list.svg

+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 238 111" xmlns:xlink="http://www.w3.org/1999/xlink"><defs><rect id="4" width="82" rx="3" height="28" fill="#fff"/><path id="5" d="m68.926 12.09v-2.41c0-.665-.437-.888-.975-.507l-6.552 4.631c-.542.383-.539.998 0 1.379l6.552 4.631c.542.383.975.154.975-.507v-2.41h4.874c.668 0 1.2-.538 1.2-1.201v-2.406c0-.668-.537-1.201-1.2-1.201h-4.874" fill="#fc8a51"/><path id="6" d="m4 24h74v-20h-74v20m-4-21c0-1.655 1.338-2.996 2.991-2.996h76.02c1.652 0 2.991 1.35 2.991 2.996v22.01c0 1.655-1.338 2.996-2.991 2.996h-76.02c-1.652 0-2.991-1.35-2.991-2.996v-22.01"/><circle id="2" cx="16" cy="14" r="7"/><circle id="0" cx="16" cy="14" r="7"/><mask id="3" width="14" height="14" x="0" y="0" fill="#fff"><use xlink:href="#2"/></mask><mask id="1" width="14" height="14" x="0" y="0" fill="#fff"><use xlink:href="#0"/></mask></defs><g fill="none" fill-rule="evenodd"><rect width="98" height="111" fill="#fff" rx="6"/><path fill="#e5e5e5" fill-rule="nonzero" d="m4 6.01v98.99c0 1.11.897 2.01 2 2.01h85.998c1.105 0 2-.897 2-2.01v-98.99c0-1.11-.897-2.01-2-2.01h-85.998c-1.105 0-2 .897-2 2.01m-4 0c0-3.318 2.685-6.01 6-6.01h85.998c3.314 0 6 2.689 6 6.01v98.99c0 3.318-2.685 6.01-6 6.01h-85.998c-3.314 0-6-2.689-6-6.01v-98.99"/><rect width="76" height="85" x="11" y="12" fill="#f9f9f9" rx="3"/><g transform="translate(37 59)"><use xlink:href="#4"/><path fill="#e5e5e5" fill-rule="nonzero" d="m4 24h74v-20h-74v20m-4-21c0-1.655 1.338-2.996 2.991-2.996h76.02c1.652 0 2.991 1.35 2.991 2.996v22.01c0 1.655-1.338 2.996-2.991 2.996h-76.02c-1.652 0-2.991-1.35-2.991-2.996v-22.01"/><use fill="#fff" stroke="#6b4fbb" stroke-width="8" mask="url(#1)" xlink:href="#0"/><use xlink:href="#5"/></g><g transform="translate(140)"><path fill="#fff" d="m0 4h94v103h-94z"/><path fill="#e5e5e5" fill-rule="nonzero" d="m0 74v30.993c0 3.318 2.687 6.01 6 6.01h85.998c3.316 0 6-2.69 6-6.01v-98.99c0-3.318-2.687-6.01-6-6.01h-85.998c-3.316 0-6 2.69-6 6.01v.993h4v-.993c0-1.11.896-2.01 2-2.01h85.998c1.105 0 2 .897 2 2.01v98.99c0 1.11-.896 2.01-2 2.01h-85.998c-1.105 0-2-.897-2-2.01v-30.993h-4"/><g fill="#f9f9f9"><rect width="82" height="28" x="8" y="12" rx="3"/><rect width="82" height="28" x="8" y="43" rx="3"/></g></g><g fill-rule="nonzero" transform="translate(148 73)"><use fill="#e5e5e5" xlink:href="#6"/><path fill="#6b4fbb" d="m17 17c1.657 0 3-1.343 3-3 0-1.657-1.343-3-3-3-1.657 0-3 1.343-3 3 0 1.657 1.343 3 3 3m0 4c-3.866 0-7-3.134-7-7 0-3.866 3.134-7 7-7 3.866 0 7 3.134 7 7 0 3.866-3.134 7-7 7"/></g><g transform="translate(25 24)"><use xlink:href="#4"/><use fill="#e5e5e5" fill-rule="nonzero" xlink:href="#6"/><use fill="#fff" stroke="#6b4fbb" stroke-width="8" mask="url(#3)" xlink:href="#2"/><use xlink:href="#5"/></g><g transform="translate(107 10)"><use xlink:href="#4"/><use fill="#fc8a51" fill-opacity=".3" fill-rule="nonzero" xlink:href="#6"/><path fill="#6b4fbb" fill-rule="nonzero" d="m16 17c1.657 0 3-1.343 3-3 0-1.657-1.343-3-3-3-1.657 0-3 1.343-3 3 0 1.657 1.343 3 3 3m0 4c-3.866 0-7-3.134-7-7 0-3.866 3.134-7 7-7 3.866 0 7 3.134 7 7 0 3.866-3.134 7-7 7" id="7"/><use xlink:href="#5"/></g><g transform="translate(128 41)"><use xlink:href="#4"/><use fill="#fc8a51" fill-opacity=".3" fill-rule="nonzero" xlink:href="#6"/><use xlink:href="#7"/><path fill="#fc8a51" d="m66.926 12.09v-2.41c0-.665-.437-.888-.975-.507l-6.552 4.631c-.542.383-.539.998 0 1.379l6.552 4.631c.542.383.975.154.975-.507v-2.41h4.874c.668 0 1.2-.538 1.2-1.201v-2.406c0-.668-.537-1.201-1.2-1.201h-4.874"/></g></g></svg>
\ No newline at end of file

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

@@ -8,17 +8,23 @@
 
 - content_for :page_specific_javascripts do
   = page_specific_javascript_bundle_tag('filtered_search')
+  = page_specific_javascript_bundle_tag('issues')
 
 = content_for :meta_tags do
   = auto_discovery_link_tag(:atom, params.merge(rss_url_options), title: "#{@project.name} issues")
 
 - if project_issues(@project).exists?
+  - if current_user
+    = render "projects/issues/export_issues/csv_download"
   %div{ class: (container_class) }
     .top-area
       = render 'shared/issuable/nav', type: :issues
       .nav-controls
         = link_to params.merge(rss_url_options), class: 'btn append-right-10 has-tooltip', title: 'Subscribe' do
           = icon('rss')
+        - if current_user
+          %button.csv_download_link.btn.append-right-10.has-tooltip{ title: 'Export as CSV' }
+            = icon('download')
         - if can? current_user, :create_issue, @project
           = link_to new_namespace_project_issue_path(@project.namespace,
                                                      @project,

app/workers/export_csv_worker.rb

+class ExportCsvWorker
+  include Sidekiq::Worker
+  include DedicatedSidekiqQueue
+
+  def perform(current_user_id, project_id, params)
+    @current_user = User.find(current_user_id)
+    @project = Project.find(project_id)
+
+    params[:project_id] = project_id
+
+    issues = IssuesFinder.new(@current_user, params.symbolize_keys).execute
+
+    Issues::ExportCsvService.new(issues).email(@current_user, @project)
+  end
+end

changelogs/unreleased-ee/1480-export-issues-csv.yml

+---
+title: Issues can be exported as CSV, via email
+merge_request: 1126
+author:

config/initializers/date_time_formats.rb

@@ -2,8 +2,10 @@
 # :medium - Nov 10, 2007
 # :long   - November 10, 2007
 Date::DATE_FORMATS[:medium] = '%b %-d, %Y'
+Date::DATE_FORMATS[:csv] = '%Y-%m-%d'
 
 # :short  - 18 Jan 06:10
 # :medium - Jan 18, 2007 6:10am
 # :long   - January 18, 2007 06:10
 Time::DATE_FORMATS[:medium] = '%b %-d, %Y %-I:%M%P'
+Time::DATE_FORMATS[:csv] = '%Y-%m-%d %H:%M:%S'

config/routes/project.rb

@@ -284,7 +284,8 @@ constraints(ProjectUrlConstrainer.new) do
           get :can_create_branch
         end
         collection do
-          post  :bulk_update
+          post :bulk_update
+          post :export_csv
         end
       end
 

config/sidekiq_queues.yml

@@ -59,3 +59,4 @@
   - [admin_emails, 1]
   - [geo_repository_update, 1]
   - [elastic_batch_project_indexer, 1]
+  - [export_csv, 1]

config/webpack.config.js

@@ -32,6 +32,7 @@ var config = {
     filtered_search:      './filtered_search/filtered_search_bundle.js',
     graphs:               './graphs/graphs_bundle.js',
     groups_list:          './groups_list.js',
+    issues:               './issues/issues_bundle.js',
     issuable:             './issuable/issuable_bundle.js',
     merge_conflicts:      './merge_conflicts/merge_conflicts_bundle.js',
     merge_request_widget: './merge_request_widget/ci_bundle.js',

lib/csv_builder.rb

+# Generates CSV when given a collection and a mapping.
+#
+# Example:
+#
+#     columns = {
+#       'Title' => 'title',
+#       'Comment' => 'comment',
+#       'Author' => -> (post) { post.author.full_name }
+#       'Created At (UTC)' => -> (post) { post.created_at&.strftime('%Y-%m-%d %H:%M:%S') }
+#     }
+#
+#     CsvBuilder.new(@posts, columns).render
+#
+class CsvBuilder
+  #
+  # * +collection+ - The data collection to be used
+  # * +header_to_hash_value+ - A hash of 'Column Heading' => 'value_method'.
+  #
+  # The value method will be called once for each object in the collection, to
+  # determine the value for that row. It can either be the name of a method on
+  # the object, or a lamda to call passing in the object.
+  def initialize(collection, header_to_value_hash)
+    @header_to_value_hash = header_to_value_hash
+    @collection = collection
+    @truncated = false
+    @rows_written = 0
+  end
+
+  # Renders the csv to a string
+  def render(truncate_after_bytes = nil)
+    tempfile = Tempfile.new('csv_export')
+    csv = CSV.new(tempfile)
+
+    write_csv csv, until_condition: -> do
+      truncate_after_bytes && tempfile.size > truncate_after_bytes
+    end
+
+    tempfile.rewind
+    tempfile.read
+  ensure
+    tempfile.close
+    tempfile.unlink
+  end
+
+  def truncated?
+    @truncated
+  end
+
+  def rows_written
+    @rows_written
+  end
+
+  def rows_expected
+    if truncated? || rows_written == 0
+      @collection.count
+    else
+      rows_written
+    end
+  end
+
+  def status
+    {
+      truncated: truncated?,
+      rows_written: rows_written,
+      rows_expected: rows_expected
+    }
+  end
+
+  private
+
+  def headers
+    @headers ||= @header_to_value_hash.keys
+  end
+
+  def attributes
+    @attributes ||= @header_to_value_hash.values
+  end
+
+  def row(object)
+    attributes.map do |attribute|
+      if attribute.respond_to?(:call)
+        attribute.call(object)
+      else
+        object.public_send(attribute)
+      end
+    end
+  end
+
+  def write_csv(csv, until_condition:)
+    csv << headers
+
+    @collection.find_each do |object|
+      csv << row(object)
+
+      @rows_written += 1
+
+      if until_condition.call
+        @truncated = true
+        break
+      end
+    end
+  end
+end

spec/features/issues/csv_spec.rb

+require 'spec_helper'
+
+describe 'Issues csv', feature: true do
+  let(:user) { create(:user) }
+  let(:project) { create(:empty_project, :public) }
+  let(:milestone) { create(:milestone, title: 'v1.0', project: project) }
+  let(:idea_label) { create(:label, project: project, title: 'Idea') }
+  let(:feature_label) { create(:label, project: project, title: 'Feature') }
+  let!(:issue)  { create(:issue, project: project, author: user) }
+
+  before { login_as(user) }
+
+  def request_csv(params = {})
+    visit namespace_project_issues_path(project.namespace, project, params)
+    click_on 'Export as CSV'
+    click_on 'Export issues'
+  end
+
+  def attachment
+    ActionMailer::Base.deliveries.last.attachments.first
+  end
+
+  def csv
+    CSV.parse(attachment.decode_body, headers: true)
+  end
+
+  it 'triggers an email export' do
+    expect(ExportCsvWorker).to receive(:perform_async).with(user.id, project.id, hash_including(project_id: project.id))
+
+    request_csv
+  end
+
+  it "doesn't send request params to ExportCsvWorker" do
+    expect(ExportCsvWorker).to receive(:perform_async).with(anything, anything, hash_excluding(controller: anything, action: anything))
+
+    request_csv
+  end
+
+  it 'displays flash message' do
+    request_csv
+
+    expect(page).to have_content 'CSV export has started'
+    expect(page).to have_content "emailed to #{user.notification_email}"
+  end
+
+  it 'includes a csv attachment' do
+    request_csv
+
+    expect(attachment.content_type).to include('text/csv')
+  end
+
+  it 'ignores pagination' do
+    create_list(:issue, 30, project: project, author: user)
+
+    request_csv
+
+    expect(csv.count).to eq 31
+  end
+
+  it 'uses filters from issue index' do
+    request_csv(state: :closed)
+
+    expect(csv.count).to eq 0
+  end
+
+  it 'avoids excessive database calls' do
+    control_count = ActiveRecord::QueryRecorder.new{ request_csv }.count
+    create_list(:labeled_issue,
+                10,
+                project: project,
+                assignee: user,
+                author: user,
+                milestone: milestone,
+                labels: [feature_label, idea_label])
+    expect{ request_csv }.not_to exceed_query_limit(control_count + 5)
+  end
+end

spec/lib/csv_builder_spec.rb

+require 'spec_helper'
+
+describe CsvBuilder, lib: true do
+  let(:object) { double(question: :answer) }
+  let(:fake_relation) { FakeRelation.new([object]) }
+  let(:subject) { CsvBuilder.new(fake_relation, 'Q & A' => :question, 'Reversed' => -> (o) { o.question.to_s.reverse }) }
+  let(:csv_data) { subject.render }
+
+  class FakeRelation < Array
+    def find_each(&block)
+      each(&block)
+    end
+  end
+
+  it 'generates a csv' do
+    expect(csv_data.scan(/(,|\n)/).join).to include ",\n,"
+  end
+
+  it 'uses a temporary file to reduce memory allocation' do
+    expect(CSV).to receive(:new).with(instance_of(Tempfile)).and_call_original
+
+    subject.render
+  end
+
+  it 'counts the number of rows' do
+    subject.render
+
+    expect(subject.rows_written).to eq 1
+  end
+
+  describe 'rows_expected' do
+    it 'uses rows_written if CSV rendered successfully' do
+      subject.render
+
+      expect(fake_relation).not_to receive(:count)
+      expect(subject.rows_expected).to eq 1
+    end
+
+    it 'falls back to calling .count before rendering begins' do
+      expect(subject.rows_expected).to eq 1
+    end
+  end
+
+  describe 'truncation' do
+    let(:big_object) { double(question: 'Long' * 1024) }
+    let(:row_size) { big_object.question.length * 2 }
+    let(:fake_relation) { FakeRelation.new([big_object, big_object, big_object]) }
+
+    it 'occurs after given number of bytes' do
+      expect(subject.render(row_size * 2).length).to be_between(row_size * 2, row_size * 3)
+      expect(subject).to be_truncated
+      expect(subject.rows_written).to eq 2
+    end
+
+    it 'is ignored by default' do
+      expect(subject.render.length).to be > row_size * 3
+      expect(subject.rows_written).to eq 3
+    end
+
+    it 'causes rows_expected to fall back to .count' do
+      subject.render(0)
+
+      expect(fake_relation).to receive(:count).and_call_original
+      expect(subject.rows_expected).to eq 3
+    end
+  end
+
+  it 'avoids loading all data in a single query' do
+    expect(fake_relation).to receive(:find_each)
+
+    subject.render
+  end
+
+  it 'uses hash keys as headers' do
+    expect(csv_data).to start_with 'Q & A'
+  end
+
+  it 'gets data by calling method provided as hash value' do
+    expect(csv_data).to include 'answer'
+  end
+
+  it 'allows lamdas to look up more complicated data' do
+    expect(csv_data).to include 'rewsna'
+  end
+end

spec/mailers/emails/csv_export_spec.rb

+require 'spec_helper'
+require 'email_spec'
+
+describe Notify do
+  include EmailSpec::Matchers
+  include_context 'gitlab email notification'
+
+  describe 'csv export email' do
+    let(:user) { create(:user) }
+    let(:empty_project) { create(:empty_project, path: 'myproject') }
+    let(:export_status) { { truncated: false, rows_expected: 3, rows_written: 3 } }
+    subject { Notify.issues_csv_email(user, empty_project, "dummy content", export_status) }
+    let(:attachment) { subject.attachments.first }
+
+    it 'attachment has csv mime type' do
+      expect(attachment.mime_type).to eq 'text/csv'
+    end
+
+    it 'generates a useful filename' do
+      expect(attachment.filename).to include(Date.today.year.to_s)
+      expect(attachment.filename).to include('issues')
+      expect(attachment.filename).to include('myproject')
+      expect(attachment.filename).to end_with('.csv')
+    end
+
+    it 'mentions number of issues and project name' do
+      expect(subject).to have_content '3'
+      expect(subject).to have_content empty_project.name
+    end
+
+    it "doesn't need to mention truncation by default" do
+      expect(subject).not_to have_content 'truncated'
+    end
+
+    context 'when truncated' do
+      let(:export_status) { { truncated: true, rows_expected: 12, rows_written: 10 } }
+
+      it 'mentions that the csv has been truncated' do
+        expect(subject).to have_content 'truncated'
+      end
+
+      it 'mentions the number of issues written and expected' do
+        expect(subject).to have_content '10 of 12 issues'
+      end
+    end
+  end
+end

spec/mailers/previews/issues_csv_mailer_preview.rb

+class IssuesCsvMailerPreview < ActionMailer::Preview
+  def issues_csv_export
+    user = OpenStruct.new(notification_email: 'a@example.com')
+    project = Project.unscoped.first
+
+    Notify.issues_csv_email(user, project, "Dummy,Csv\n0,1", export_status)
+  end
+
+  private
+
+  def export_status
+    {
+      truncated: [true, false].sample,
+      rows_written: 632,
+      rows_expected: 891
+    }
+  end
+end

spec/models/concerns/issuable_spec.rb

@@ -331,6 +331,16 @@ describe Issue, "Issuable" do
     end
   end
 
+  describe '.labels_hash' do
+    let(:feature_label) { create(:label, title: 'Feature') }
+    let!(:issues) { create_list(:labeled_issue, 3, labels: [feature_label]) }
+
+    it 'maps issue ids to labels titles' do
+      issue_id = issues.first.id
+      expect(Issue.labels_hash[issue_id]).to eq ['Feature']
+    end
+  end
+
   describe '#user_notes_count' do
     let(:project) { create(:empty_project) }
     let(:issue1) { create(:issue, project: project) }

spec/services/issues/export_csv_service_spec.rb

+require 'spec_helper'
+
+describe Issues::ExportCsvService, services: true do
+  let(:user) { create(:user) }
+  let(:project) { create(:empty_project, :public) }
+  let!(:issue)  { create(:issue, project: project, author: user) }
+  let(:subject) { described_class.new(Issue.all) }
+
+  it 'renders csv to string' do
+    expect(subject.csv_data).to be_a String
+  end
+
+  describe '#email' do
+    it 'emails csv' do
+      expect{ subject.email(user, project) }.to change(ActionMailer::Base.deliveries, :count)
+    end
+
+    it 'renders with a target filesize' do
+      expect(subject.csv_builder).to receive(:render).with(described_class::TARGET_FILESIZE)
+
+      subject.email(user, project)
+    end
+  end
+
+  def csv
+    CSV.parse(subject.csv_data, headers: true)
+  end
+
+  context 'includes' do
+    let(:milestone) { create(:milestone, title: 'v1.0', project: project) }
+    let(:idea_label) { create(:label, project: project, title: 'Idea') }
+    let(:feature_label) { create(:label, project: project, title: 'Feature') }
+
+    before do
+      issue.update!(milestone: milestone,
+                    assignee: user,
+                    description: 'Issue with details',
+                    state: :reopened,
+                    due_date: DateTime.new(2014, 3, 2),
+                    created_at: DateTime.new(2015, 4, 3, 2, 1, 0),
+                    updated_at: DateTime.new(2016, 5, 4, 3, 2, 1),
+                    labels: [feature_label, idea_label])
+    end
+
+    specify 'iid' do
+      expect(csv[0]['Issue ID']).to eq issue.iid.to_s
+    end
+
+    specify 'url' do
+      expect(csv[0]['URL']).to match(/http.*#{project.full_path}.*#{issue.iid}/)
+    end
+
+    specify 'title' do
+      expect(csv[0]['Title']).to eq issue.title
+    end
+
+    specify 'state' do
+      expect(csv[0]['State']).to eq 'Open'
+    end
+
+    specify 'description' do
+      expect(csv[0]['Description']).to eq issue.description
+    end
+
+    specify 'author name' do
+      expect(csv[0]['Author']).to eq issue.author_name
+    end
+
+    specify 'author username' do
+      expect(csv[0]['Author Username']).to eq issue.author.username
+    end
+
+    specify 'assignee name' do
+      expect(csv[0]['Assignee']).to eq issue.assignee_name
+    end
+
+    specify 'assignee username' do
+      expect(csv[0]['Assignee Username']).to eq issue.assignee.username
+    end
+
+    specify 'confidential' do
+      expect(csv[0]['Confidential']).to eq 'No'
+    end
+
+    specify 'milestone' do
+      expect(csv[0]['Milestone']).to eq issue.milestone.title
+    end
+
+    specify 'labels' do
+      expect(csv[0]['Labels']).to eq 'Feature,Idea'
+    end
+
+    specify 'due_date' do
+      expect(csv[0]['Due Date']).to eq '2014-03-02'
+    end
+
+    specify 'created_at' do
+      expect(csv[0]['Created At (UTC)']).to eq '2015-04-03 02:01:00'
+    end
+
+    specify 'updated_at' do
+      expect(csv[0]['Updated At (UTC)']).to eq '2016-05-04 03:02:01'
+    end
+  end
+
+  context 'with minimal details' do
+    it 'renders labels as nil' do
+      expect(csv[0]['Labels']).to eq nil
+    end
+  end
+end