add customized printing setting for headless

headless/lib/browser/headless_print_manager.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef HEADLESS_LIB_BROWSER_HEADLESS_PRINT_MANAGER_H_
 #define HEADLESS_LIB_BROWSER_HEADLESS_PRINT_MANAGER_H_
 
 #include <memory>
 #include <string>
+#include <vector>
 
 #include "components/printing/browser/print_manager.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents_user_data.h"
+#include "printing/print_settings.h"
+#include "printing/printing_export.h"
 
 struct PrintHostMsg_DidPrintPage_Params;
+struct PrintHostMsg_ScriptedPrint_Params;
+struct PrintMsg_PrintPages_Params;
 
 namespace printing {
 
+struct HeadlessPrintSettings {
+  HeadlessPrintSettings()
+      : landscape(false),
+        display_header_footer(false),
+        should_print_backgrounds(false),
+        scale(1) {}
+
+  gfx::Size paper_size_in_points;
+  PageMargins margins_in_points;
+
+  bool landscape;
+  bool display_header_footer;
+  bool should_print_backgrounds;
+  // scale = 1 means 100%.
+  double scale;
+
+  std::string page_ranges;
+};
+
 class HeadlessPrintManager
     : public PrintManager,
       public content::WebContentsUserData<HeadlessPrintManager> {
  public:
   enum PrintResult {
     PRINT_SUCCESS,
     PRINTING_FAILED,
     INVALID_PRINTER_SETTINGS,
     INVALID_MEMORY_HANDLE,
     METAFILE_MAP_ERROR,
     UNEXPECTED_VALID_MEMORY_HANDLE,
     METAFILE_INVALID_HEADER,
     METAFILE_GET_DATA_ERROR,
     SIMULTANEOUS_PRINT_ACTIVE,
+    PAGE_RANGE_SYNTAX_ERROR,
+    PAGE_COUNT_EXCEEDED,
+  };
+
+  enum PageRangeStatus {
+    NO_ERROR,
+    SYNTAX_ERROR,
+    LIMIT_ERROR,
   };
 
   using GetPDFCallback = base::Callback<void(PrintResult, const std::string&)>;
 
   ~HeadlessPrintManager() override;
 
   static std::string PrintResultToString(PrintResult result);
   static std::unique_ptr<base::DictionaryValue> PDFContentsToDictionaryValue(
       const std::string& data);
+  static PageRangeStatus PageRangeTextToPages(std::string page_range_text,

[Lei Zhang, 2017/05/04 07:29:37]

Can you pass in a base::StringPiece instead?

[jzfeng, 2017/05/05 02:41:34]

Done. When shall I use base::StringPiece? I see there are a lot of code using
it, but to me it is the same as std::string so far.

+                                              int pages_count,
+                                              std::vector<int>* pages);
 
   // Prints the current document immediately. Since the rendering is
   // asynchronous, the actual printing will not be completed on the return of
   // this function, and |callback| will always get called when printing
   // finishes.
   void GetPDFContents(content::RenderFrameHost* rfh,
+                      const HeadlessPrintSettings& settings,
                       const GetPDFCallback& callback);
 
  private:
   explicit HeadlessPrintManager(content::WebContents* web_contents);
   friend class content::WebContentsUserData<HeadlessPrintManager>;
 
+  std::unique_ptr<PrintMsg_PrintPages_Params> PrintParams(

[Lei Zhang, 2017/05/04 07:29:37]

Rename to GetPrintParamsFromSettings?

[jzfeng, 2017/05/05 02:41:34]

Done.

+      HeadlessPrintSettings settings);

[Lei Zhang, 2017/05/04 07:29:37]

Pass by const ref.

[jzfeng, 2017/05/05 02:41:34]

Done.

   // content::WebContentsObserver implementation.
   bool OnMessageReceived(const IPC::Message& message,
                          content::RenderFrameHost* render_frame_host) override;
 
   // IPC Message handlers.
   void OnGetDefaultPrintSettings(IPC::Message* reply_msg);
+  void OnScriptedPrint(const PrintHostMsg_ScriptedPrint_Params& params,
+                       IPC::Message* reply_msg);
   void OnShowInvalidPrinterSettingsError();
   void OnPrintingFailed(int cookie) override;
+  void OnDidGetPrintedPagesCount(int cookie, int number_pages) override;
   void OnDidPrintPage(const PrintHostMsg_DidPrintPage_Params& params);
 
   void Reset();
   void ReleaseJob(PrintResult result);
 
   content::RenderFrameHost* printing_rfh_;
   GetPDFCallback callback_;
+  std::unique_ptr<PrintMsg_PrintPages_Params> print_params_;
+  std::string page_ranges_text_;
   std::string data_;
 
   // Set to true when OnDidPrintPage() should be expecting the first page.
   bool expecting_first_page_;
 
   DISALLOW_COPY_AND_ASSIGN(HeadlessPrintManager);
 };
 
 }  // namespace printing
 
 #endif  // HEADLESS_LIB_BROWSER_HEADLESS_PRINT_MANAGER_H_