Add a feature flag to use the CUPS IPP printing backend on macOS

Add |printing::features::kCupsIppPrintingBackend| and the corresponding UI in chrome://flags for switching printing backends on macOS. The existing CUPS backend calls the deprecated PPD API. In a future CL, the switch will allow use of the CUPS IPP backend, which uses an up-to-date API for fetching printer attributes and managing printers. The flag does not do anything yet. Bug: 226176 Change-Id: Ifbacfbd1872eb7c47b3130694de920a94f42fc15 Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2063220 Commit-Queue: Daniel Hosseinian <dhoss@chromium.org> Reviewed-by: Lei Zhang <thestig@chromium.org> Reviewed-by: Sean Kau <skau@chromium.org> Cr-Commit-Position: refs/heads/master@{#750018}
marcosholgado · Mar 13, 2020 · 159cb3d · 159cb3d
1 parent a6a3bfc
commit 159cb3d
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Showing 7 changed files with 48 additions and 5 deletions.
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
@@ -3372,6 +3372,13 @@ const FeatureEntry kFeatureEntries[] = {
 #endif  // BUILDFLAG(ENABLE_PDF)
 
 #if BUILDFLAG(ENABLE_PRINTING)
+#if defined(OS_MACOSX)
+    {"cups-ipp-printing-backend",
+     flag_descriptions::kCupsIppPrintingBackendName,
+     flag_descriptions::kCupsIppPrintingBackendDescription, kOsMac,
+     FEATURE_VALUE_TYPE(printing::features::kCupsIppPrintingBackend)},
+#endif  // defined(OS_MACOSX)
+
 #if defined(OS_WIN)
     {"use-xps-for-printing", flag_descriptions::kUseXpsForPrintingName,
      flag_descriptions::kUseXpsForPrintingDescription, kOsWin,

diff --git a/chrome/browser/flag-metadata.json b/chrome/browser/flag-metadata.json
@@ -660,6 +660,11 @@
     "owners": [ "khorimoto", "nohle" ],
     "expiry_milestone": 86
   },
+  {
+    "name": "cups-ipp-printing-backend",
+    "owners": [ "dhoss", "chrome-print@google.com" ],
+    "expiry_milestone": 89
+  },
   {
     "name": "d3d11-video-decoder",
     "owners": [ "liberato", "tmathmeyer", "videostack-eng" ],

diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
@@ -2845,6 +2845,7 @@ const char kUseWinrtMidiApiDescription[] =
     "Use Windows Runtime MIDI API for WebMIDI (effective only on Windows 10 or "
     "later).";
 
+#if BUILDFLAG(ENABLE_PRINTING)
 const char kUseXpsForPrintingName[] = "Use XPS for printing";
 const char kUseXpsForPrintingDescription[] =
     "When enabled, use XPS printing API instead of the GDI print API.";
@@ -2853,6 +2854,7 @@ const char kUseXpsForPrintingFromPdfName[] = "Use XPS for printing from PDF";
 const char kUseXpsForPrintingFromPdfDescription[] =
     "When enabled, use XPS printing API instead of the GDI print API when "
     "printing PDF documents.";
+#endif  // BUILDFLAG(ENABLE_PRINTING)
 
 #if BUILDFLAG(ENABLE_SPELLCHECK)
 const char kWinUseBrowserSpellCheckerName[] =
@@ -2880,6 +2882,13 @@ const char kWinUseHybridSpellCheckerDescription[] =
 
 #if defined(OS_MACOSX)
 
+#if BUILDFLAG(ENABLE_PRINTING)
+const char kCupsIppPrintingBackendName[] = "CUPS IPP Printing Backend";
+const char kCupsIppPrintingBackendDescription[] =
+    "Use the CUPS IPP printing backend instead of the original CUPS backend "
+    "that calls the PPD API.";
+#endif  // BUILDFLAG(ENABLE_PRINTING)
+
 const char kImmersiveFullscreenName[] = "Immersive Fullscreen Toolbar";
 const char kImmersiveFullscreenDescription[] =
     "Automatically hide and show the toolbar in fullscreen.";

diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
@@ -16,6 +16,7 @@
 #include "device/vr/buildflags/buildflags.h"
 #include "media/media_buildflags.h"
 #include "ppapi/buildflags/buildflags.h"
+#include "printing/buildflags/buildflags.h"
 
 #if defined(OS_LINUX)
 #include "base/allocator/buildflags.h"
@@ -1629,11 +1630,13 @@ extern const char kUseAngleD3D11on12[];
 extern const char kUseWinrtMidiApiName[];
 extern const char kUseWinrtMidiApiDescription[];
 
+#if BUILDFLAG(ENABLE_PRINTING)
 extern const char kUseXpsForPrintingName[];
 extern const char kUseXpsForPrintingDescription[];
 
 extern const char kUseXpsForPrintingFromPdfName[];
 extern const char kUseXpsForPrintingFromPdfDescription[];
+#endif  // BUILDFLAG(ENABLE_PRINTING)
 
 #if BUILDFLAG(ENABLE_SPELLCHECK)
 extern const char kWinUseBrowserSpellCheckerName[];
@@ -1652,6 +1655,11 @@ extern const char kWinUseHybridSpellCheckerDescription[];
 
 #if defined(OS_MACOSX)
 
+#if BUILDFLAG(ENABLE_PRINTING)
+extern const char kCupsIppPrintingBackendName[];
+extern const char kCupsIppPrintingBackendDescription[];
+#endif  // BUILDFLAG(ENABLE_PRINTING)
+
 extern const char kImmersiveFullscreenName[];
 extern const char kImmersiveFullscreenDescription[];
 

diff --git a/printing/printing_features.cc b/printing/printing_features.cc
@@ -13,12 +13,19 @@ const base::Feature kAdvancedPpdAttributes{"AdvancedPpdAttributes",
                                            base::FEATURE_ENABLED_BY_DEFAULT};
 #endif  // defined(OS_CHROMEOS)
 
+#if defined(OS_MACOSX)
+// Use the CUPS IPP printing backend instead of the original CUPS backend that
+// calls the deprecated PPD API.
+const base::Feature kCupsIppPrintingBackend{"CupsIppPrintingBackend",
+                                            base::FEATURE_DISABLED_BY_DEFAULT};
+#endif  // defined(OS_MACOSX)
+
 #if defined(OS_WIN)
 // Use XPS for printing instead of GDI.
 const base::Feature kUseXpsForPrinting{"UseXpsForPrinting",
                                        base::FEATURE_DISABLED_BY_DEFAULT};
 
-// Use XPS for printing instead of GDI for printing PDF documents.   This is
+// Use XPS for printing instead of GDI for printing PDF documents. This is
 // independent of |kUseXpsForPrinting|; can use XPS for PDFs even if still using
 // GDI for modifiable content.
 const base::Feature kUseXpsForPrintingFromPdf{

diff --git a/printing/printing_features.h b/printing/printing_features.h
@@ -12,11 +12,16 @@
 namespace printing {
 namespace features {
 
+// The following features are declared alphabetically. The features should be
+// documented with descriptions of their behaviors in the .cc file.
+
 #if defined(OS_CHROMEOS)
-// All features in alphabetical order. The features should be documented
-// alongside the definition of their values in the .cc file.
 PRINTING_EXPORT extern const base::Feature kAdvancedPpdAttributes;
-#endif
+#endif  // defined(OS_CHROMEOS)
+
+#if defined(OS_MACOSX)
+PRINTING_EXPORT extern const base::Feature kCupsIppPrintingBackend;
+#endif  // defined(OS_MACOSX)
 
 #if defined(OS_WIN)
 PRINTING_EXPORT extern const base::Feature kUseXpsForPrinting;
@@ -29,7 +34,7 @@ PRINTING_EXPORT bool IsXpsPrintCapabilityRequired();
 // Helper function to determine if printing of a document from a particular
 // source should be done using XPS printing API instead of with GDI.
 PRINTING_EXPORT bool ShouldPrintUsingXps(bool source_is_pdf);
-#endif
+#endif  // defined(OS_WIN)
 
 PRINTING_EXPORT extern const base::Feature kUseFrameAssociatedLoaderFactory;
 

diff --git a/tools/metrics/histograms/enums.xml b/tools/metrics/histograms/enums.xml
@@ -38330,6 +38330,7 @@ from previous Chrome versions.
   <int value="-920204598" label="ScrollAnchorSerialization:enabled"/>
   <int value="-918900957" label="AutofillCreditCardAssist:disabled"/>
   <int value="-918618075" label="enable-service-worker"/>
+  <int value="-915328316" label="CupsIppPrintingBackend:disabled"/>
   <int value="-915035507" label="ArcPrintSpoolerExperiment:enabled"/>
   <int value="-914210146" label="enable-web-based-signin"/>
   <int value="-914097698" label="EnableDbusAndX11StatusIcons:disabled"/>
@@ -40404,6 +40405,7 @@ from previous Chrome versions.
   <int value="1603578716" label="CaptionSettings:disabled"/>
   <int value="1605398303" label="MacSystemMediaPermissionsInfoUI:enabled"/>
   <int value="1605611615" label="enable-webrtc-srtp-aes-gcm"/>
+  <int value="1609059016" label="CupsIppPrintingBackend:enabled"/>
   <int value="1611522475" label="AutofillPrimaryInfoStyleExperiment:disabled"/>
   <int value="1612206633" label="CCTModuleCustomHeader:enabled"/>
   <int value="1612446645" label="enable-weak-memorycache"/>