Hash fingerprint for notice payload.

Author: Joshua Wood

README.md

@@ -198,8 +198,8 @@ By default, we group errors in two ways:
 1. "Strict" grouping generates a fingerprint using a hash of the error
    class, component (if available), and the entire backtrace. When the
    backtrace changes, a new error is created by Honeybadger.
-2. "Loose" grouping uses only the error class, component (if available),
-   and the first line of the application trace.
+2. "Loose" grouping uses the error class, component (if available), and
+   the application trace.
 
 You can choose to use strict or loose grouping from your Honeybadger
 project settings page. If you want to use your own grouping strategy,
@@ -213,7 +213,7 @@ we'll use that for grouping errors instead of the default:
       # See lib/honeybadger/notice.rb for the options that are available
       # on the notice object
       config.fingerprint do |notice|
-        Digest::SHA1.hexdigest([notice[:error_class], notice[:component], notice[:backtrace].to_s].join(':'))
+        [notice[:error_class], notice[:component], notice[:backtrace].to_s].join(':')
       end
 
     end
@@ -223,6 +223,9 @@ directly:
 
     Honeybadger.notify(StandardError.new('oh noes!'), :fingerprint => 'asdf')
 
+The fingerprint can be any Ruby object that responds to #to_s, and will
+be sent to Honeybadger as a SHA1 hash.
+
 *Please note that to make use of this option, you must have **strict**
 grouping disabled on your project settings page.*
 

lib/honeybadger.rb

@@ -1,6 +1,7 @@
 require 'net/http'
 require 'net/https'
 require 'json'
+require 'digest'
 require 'logger'
 
 require 'honeybadger/configuration'

lib/honeybadger/configuration.rb

@@ -267,14 +267,14 @@ def async
 
     # Public: Generate custom fingerprint (optional)
     #
-    # block - An optional block returning calculated fingerprint
+    # block - An optional block returning object responding to #to_s
     #
     # Examples
     #
     #   config.fingerprint = Proc.new { |notice| ... }
     #
     #   config.fingerprint do |notice|
-    #     Digest::SHA1.hexdigest([notice[:error_class], notice[:component], notice[:backtrace].to_s].join(':'))
+    #     [notice[:error_class], notice[:component], notice[:backtrace].to_s].join(':')
     #   end
     #
     # Returns configured fingerprint generator (should respond to #call(notice))

lib/honeybadger/notice.rb

@@ -103,7 +103,7 @@ def initialize(args)
       self.environment_name = args[:environment_name]
       self.cgi_data         = args[:cgi_data] || args[:rack_env]
       self.backtrace        = Backtrace.parse(exception_attribute(:backtrace, caller), :filters => self.backtrace_filters)
-      self.fingerprint      = generated_fingerprint
+      self.fingerprint      = hashed_fingerprint
       self.error_class      = exception_attribute(:error_class) {|exception| exception.class.name }
       self.error_message    = exception_attribute(:error_message, 'Notification') do |exception|
         "#{exception.class.name}: #{exception.message}"
@@ -300,14 +300,21 @@ def clean_rack_request_data
       end
     end
 
-    def generated_fingerprint
+    def fingerprint_from_args
       if args[:fingerprint].respond_to?(:call)
         args[:fingerprint].call(self)
       else
         args[:fingerprint]
       end
     end
 
+    def hashed_fingerprint
+      fingerprint = fingerprint_from_args
+      if fingerprint && fingerprint.respond_to?(:to_s)
+        Digest::SHA1.hexdigest(fingerprint.to_s)
+      end
+    end
+
     def extract_source_from_backtrace
       if backtrace.lines.empty?
         nil

test/unit/notice_test.rb

@@ -86,14 +86,19 @@ def stub_request(attrs = {})
       assert_equal nil, notice.fingerprint
     end
 
-    should "accepts fingerprint as string" do
+    should "accept fingerprint as string" do
       notice = build_notice({ :fingerprint => 'foo' })
-      assert_equal 'foo', notice.fingerprint
+      assert_equal '0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33', notice.fingerprint
     end
 
-    should "accepts fingerprint responding to #call" do
+    should "accept fingerprint responding to #call" do
       notice = build_notice({ :fingerprint => mock(:call => 'foo') })
-      assert_equal 'foo', notice.fingerprint
+      assert_equal '0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33', notice.fingerprint
+    end
+
+    should "accept fingerprint using #to_s" do
+      notice = build_notice({ :fingerprint => mock(:to_s => 'foo') })
+      assert_equal '0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33', notice.fingerprint
     end
   end