Implement screenshots #11

cuprite.gemspec

@@ -31,4 +31,5 @@ Gem::Specification.new do |s|
   s.add_development_dependency "launchy",    "~> 2.4"
   s.add_development_dependency "byebug",     "~> 10.0"
   s.add_development_dependency "puma",       "~> 3.0"
+  s.add_development_dependency "chunky_png", "~> 1.3"
 end

lib/capybara/cuprite/browser.rb

@@ -90,21 +90,20 @@ def select_file(node, value)
       raise NotImplementedError
     end
 
-    def render(path, _options = {})
-      # check_render_options!(options)
-      # options[:full] = !!options[:full]
-      data = Base64.decode64(render_base64)
-      File.open(path.to_s, "wb") { |f| f.write(data) }
+    def render(path, options = {})
+      format = options.delete(:format)
+      options = options.merge(path: path)
+      bin = Base64.decode64(render_base64(format, options))
+      File.open(path.to_s, "wb") { |f| f.write(bin) }
     end
 
-    def render_base64(format = "png", _options = {})
-      # check_render_options!(options)
-      # options[:full] = !!options[:full]
-      page.command("Page.captureScreenshot", format: format)["data"]
+    def render_base64(format, options = {})
+      options = render_options(format, options)
+      page.command("Page.captureScreenshot", **options)["data"]
     end
 
     def set_zoom_factor(zoom_factor)
-      raise NotImplementedError
+      @zoom_factor = zoom_factor.to_f
     end
 
     def set_paper_size(size)
@@ -185,6 +184,7 @@ def clear_memory_cache
 
     def reset
       @headers = {}
+      @zoom_factor = nil
       targets.reset
     end
 
@@ -223,10 +223,36 @@ def start
       @client = Client.new(self, @process.ws_url)
     end
 
-    def check_render_options!(options)
-      return if !options[:full] || !options.key?(:selector)
-      warn "Ignoring :selector in #render since :full => true was given at #{caller(1..1).first}"
-      options.delete(:selector)
+    def render_options(format, opts)
+      options = {}
+
+      format ||= File.extname(opts[:path]).delete(".") || "png"
+      format = "jpeg" if format == "jpg"
+      raise "Not supported format: #{format}. jpeg | png" if format !~ /jpeg|png/i
+      options.merge!(format: format)
+
+      options.merge!(quality: opts[:quality] ? opts[:quality] : 75) if format == "jpeg"
+
+      warn "Ignoring :selector in #render since full: true was given at #{caller(1..1).first}" if !!opts[:full] && opts[:selector]
+
+      if !!opts[:full]
+        width, height = page.evaluate("[document.documentElement.offsetWidth, document.documentElement.offsetHeight]")
+        options.merge!(clip: { x: 0, y: 0, width: width, height: height, scale: @zoom_factor || 1.0 }) if width > 0 && height > 0
+      elsif opts[:selector]
+        rect = page.evaluate("document.querySelector('#{opts[:selector]}').getBoundingClientRect()")
+        options.merge!(clip: { x: rect["x"], y: rect["y"], width: rect["width"], height: rect["height"], scale: @zoom_factor || 1.0 })
+      end
+
+      if @zoom_factor
+        if !options[:clip]
+          width, height = page.evaluate("[document.documentElement.clientWidth, document.documentElement.clientHeight]")
+          options[:clip] = { x: 0, y: 0, width: width, height: height }
+        end
+
+        options[:clip].merge!(scale: @zoom_factor)
+      end
+
+      options
     end
 
     def find_all(method, selector, within = nil)

spec/integration/driver_spec.rb

@@ -3,6 +3,7 @@
 require "spec_helper"
 require "image_size"
 require "pdf/reader"
+require "chunky_png"
 
 module Capybara::Cuprite
   describe Driver do
@@ -100,7 +101,7 @@ def session_url(path)
       expect(@session.current_window.size).to eq([1366, 768])
     end
 
-    it "allows custom maximization size", skip: true do
+    it "allows custom maximization size" do
       begin
         @driver.options[:screen_size] = [1600, 1200]
         @session.visit("/")
@@ -200,14 +201,14 @@ def session_url(path)
         el = @session.find(:css, "#middleish")
         # make the page scroll an element into view
         el.click
-        position_script = "document.querySelector("#middleish").getBoundingClientRect()"
+        position_script = "document.querySelector('#middleish').getBoundingClientRect()"
         offset = @session.evaluate_script(position_script)
         create_screenshot file
         expect(@session.evaluate_script(position_script)).to eq offset
       end
     end
 
-    describe "#save_screenshot", skip: true do
+    describe "#save_screenshot" do
       let(:format) { :png }
       let(:file) { CUPRITE_ROOT + "/spec/tmp/screenshot.#{format}" }
 
@@ -248,30 +249,29 @@ def create_screenshot(file, *args)
       end
 
       it "supports rendering the page with different quality settings" do
-        file2 = CUPRITE_ROOT + "/spec/tmp/screenshot2.#{format}"
-        file3 = CUPRITE_ROOT + "/spec/tmp/screenshot3.#{format}"
+        file2 = CUPRITE_ROOT + "/spec/tmp/screenshot2.jpeg"
+        file3 = CUPRITE_ROOT + "/spec/tmp/screenshot3.jpeg"
         FileUtils.rm_f [file2, file3]
 
         begin
           @session.visit("/")
-          @driver.save_screenshot(file, quality: 0)
+          @driver.save_screenshot(file, quality: 0) # ignored for png
           @driver.save_screenshot(file2) # defaults to a quality of 75
           @driver.save_screenshot(file3, quality: 100)
-          expect(File.size(file)).to be < File.size(file2)
+          expect(File.size(file)).to be > File.size(file2) # png by defult is bigger
           expect(File.size(file2)).to be < File.size(file3)
         ensure
           FileUtils.rm_f [file2, file3]
         end
       end
 
       shared_examples "when #zoom_factor= is set" do
-        let(:format) { :xbm }
-
         it "changes image dimensions" do
           @session.visit("/cuprite/zoom_test")
 
           black_pixels_count = lambda { |file|
-            File.read(file).to_s[/{.*}/m][1...-1].split(/\W/).map { |n| n.hex.to_s(2).count("1") }.reduce(:+)
+            img = ChunkyPNG::Image.from_file(file)
+            img.pixels.inject(0) { |i, p| p > 255 ? i + 1 : i }
           }
           @driver.save_screenshot(file)
           before = black_pixels_count[file]
@@ -294,7 +294,7 @@ def create_screenshot(file, *args)
         include_examples "when #zoom_factor= is set"
       end
 
-      context "when #paper_size= is set" do
+      context "when #paper_size= is set", skip: true do
         let(:format) { :pdf }
 
         it "changes pdf size" do
@@ -315,7 +315,7 @@ def create_screenshot(file, *args)
       include_examples "render screen"
     end
 
-    describe "#render_base64", skip: true do
+    describe "#render_base64" do
       let(:file) { CUPRITE_ROOT + "/spec/tmp/screenshot.#{format}" }
 
       def create_screenshot(file, *args)