Track printer protocol usage for CUPS printers.

Add a metric called CUPS.PrinterProtocol that records the protocol for
a selected printer. This will be used to track usage of the various
protocols to prioritize effort.

BUG=726103

Review-Url: https://codereview.chromium.org/2903113002
Cr-Commit-Position: refs/heads/master@{#474859}

chrome/browser/ui/webui/print_preview/printer_backend_proxy_chromeos.cc

@@ -11,6 +11,7 @@
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/task_scheduler/post_task.h"
 #include "base/values.h"
 #include "chrome/browser/chromeos/printing/cups_print_job_manager.h"
@@ -123,6 +124,11 @@ class PrinterBackendProxyChromeos : public PrinterBackendProxy {
       return;
     }
 
+    // Log printer configuration for selected printer.
+    UMA_HISTOGRAM_ENUMERATION("Printing.CUPS.ProtocolUsed",
+                              printer->GetProtocol(),
+                              chromeos::Printer::kProtocolMax);
+
     if (prefs_->IsConfigurationCurrent(*printer)) {
       // Skip setup if the printer is already installed.
       HandlePrinterSetup(std::move(printer), cb, chromeos::SUCCESS);

chromeos/printing/printer_configuration.cc

@@ -7,6 +7,7 @@
 #include <string>
 
 #include "base/guid.h"
+#include "base/strings/string_piece.h"
 
 namespace chromeos {
 
@@ -30,4 +31,31 @@ bool Printer::IsIppEverywhere() const {
   return ppd_reference_.autoconf;
 }
 
+Printer::PrinterProtocol Printer::GetProtocol() const {
+  const base::StringPiece uri(uri_);
+
+  if (uri.starts_with("usb:"))
+    return PrinterProtocol::kUsb;
+
+  if (uri.starts_with("ipp:"))
+    return PrinterProtocol::kIpp;
+
+  if (uri.starts_with("ipps:"))
+    return PrinterProtocol::kIpps;
+
+  if (uri.starts_with("http:"))
+    return PrinterProtocol::kHttp;
+
+  if (uri.starts_with("https:"))
+    return PrinterProtocol::kHttps;
+
+  if (uri.starts_with("socket:"))
+    return PrinterProtocol::kSocket;
+
+  if (uri.starts_with("lpd:"))
+    return PrinterProtocol::kLpd;
+
+  return PrinterProtocol::kUnknown;
+}
+
 }  // namespace chromeos

chromeos/printing/printer_configuration.h

@@ -47,6 +47,20 @@ class CHROMEOS_EXPORT Printer {
     SRC_POLICY,
   };
 
+  // An enumeration of printer protocols.  Do not change these values as they
+  // are used in enums.xml.
+  enum PrinterProtocol {
+    kUnknown = 0,
+    kUsb = 1,
+    kIpp = 2,
+    kIpps = 3,
+    kHttp = 4,
+    kHttps = 5,
+    kSocket = 6,
+    kLpd = 7,
+    kProtocolMax
+  };
+
   // Constructs a printer object that is completely empty.
   Printer();
 
@@ -94,6 +108,9 @@ class CHROMEOS_EXPORT Printer {
   // |uri_|.
   bool IsIppEverywhere() const;
 
+  // Returns the printer protocol the printer is configured with.
+  Printer::PrinterProtocol GetProtocol() const;
+
   Source source() const { return source_; }
   void set_source(const Source source) { source_ = source; }
 

tools/metrics/histograms/enums.xml

@@ -29130,6 +29130,17 @@ from previous Chrome versions.
   <int value="1" label="The user chose to reload the full page."/>
 </enum>
 
+<enum name="PrinterProtocol" type="int">
+  <int value="0" label="Unknown"/>
+  <int value="1" label="Universal Serial Bus (usb)"/>
+  <int value="2" label="Internet Print Protocol (ipp)"/>
+  <int value="3" label="Internet Print Protocol Secure (ipps)"/>
+  <int value="4" label="HyperText Transfer Protocol (http)"/>
+  <int value="5" label="HyperText Transfer Protocol Secure (https)"/>
+  <int value="6" label="App Socket (socket)"/>
+  <int value="7" label="Line Print Daemon (lpd)"/>
+</enum>
+
 <enum name="PrinterServiceEventType" type="int">
   <int value="0" label="Printer added"/>
   <int value="1" label="Page displayed (Deprecated)"/>

tools/metrics/histograms/histograms.xml

@@ -57061,6 +57061,16 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Printing.CUPS.ProtocolUsed" enum="PrinterProtocol">
+  <owner>skau@chromium.org</owner>
+  <summary>
+    Records the protocol for a selected printer in Chrome OS.  Used to track
+    usage of the various printer protocols.  Since a selection occurs when print
+    preview is opened, this will count at least one every time that happens if a
+    CUPS printer was selected.
+  </summary>
+</histogram>
+
 <histogram name="PrintPreview.DestinationAction"
     enum="PrintPreviewPrintDestinationBuckets">
   <owner>vitalybuka@chromium.org</owner>