Reject printers with invalid uri when parsing JSON.

Previous behavior was to accept the uri and CUPS would reject it when we
try to use it.  Received a report of this happening in TT.
This will help to surface the root cause for users.

Bug: 844521
Change-Id: I77a20232a7317ee40c7c3c0fa534d73d9aad2b4b
Reviewed-on: https://chromium-review.googlesource.com/1066392
Commit-Queue: Sean Kau <skau@chromium.org>
Reviewed-by: Xiaoqian Dai <xdai@chromium.org>
Cr-Commit-Position: refs/heads/master@{#560912}

chromeos/printing/printer_translator.cc

@@ -34,6 +34,24 @@ const char kUUID[] = "uuid";
 const char kPpdResource[] = "ppd_resource";
 const char kGuid[] = "guid";
 
+// Returns true if the uri was retrieved, is valid, and was set on |printer|.
+// Returns false otherwise.
+bool SetUri(const DictionaryValue& dict, Printer* printer) {
+  std::string uri;
+  if (!dict.GetString(kUri, &uri)) {
+    LOG(WARNING) << "Uri required";
+    return false;
+  }
+
+  if (!chromeos::ParseUri(uri).has_value()) {
+    LOG(WARNING) << "Uri is malformed";
+    return false;
+  }
+
+  printer->set_uri(uri);
+  return true;
+}
+
 // Populates the |printer| object with corresponding fields from |value|.
 // Returns false if |value| is missing a required field.
 bool DictionaryToPrinter(const DictionaryValue& value, Printer* printer) {
@@ -46,11 +64,7 @@ bool DictionaryToPrinter(const DictionaryValue& value, Printer* printer) {
     return false;
   }
 
-  std::string uri;
-  if (value.GetString(kUri, &uri)) {
-    printer->set_uri(uri);
-  } else {
-    LOG(WARNING) << "Uri required";
+  if (!SetUri(value, printer)) {
     return false;
   }
 

chromeos/printing/printer_translator_unittest.cc

@@ -129,6 +129,19 @@ TEST(PrinterTranslatorTest, MissingEffectiveMakeModelFails) {
   EXPECT_FALSE(printer);
 }
 
+TEST(PrinterTranslatorTest, InvalidUriFails) {
+  base::DictionaryValue preference;
+  preference.SetString("id", kHash);
+  preference.SetString("display_name", kName);
+  preference.SetString("ppd_resource.effective_model", kEffectiveMakeAndModel);
+
+  // uri with dangling colon
+  preference.SetString("uri", "ipp://hostname.tld:");
+
+  std::unique_ptr<Printer> printer = RecommendedPrinterToPrinter(preference);
+  EXPECT_FALSE(printer);
+}
+
 TEST(PrinterTranslatorTest, RecommendedPrinterMinimalSetup) {
   base::DictionaryValue preference;
   preference.SetString("id", kHash);