Allow escaping of JSONPath outputs; demonstrate in the formatting agent.

app/models/agents/event_formatting_agent.rb

@@ -24,7 +24,7 @@ module Agents
             subject: "$.data"
           }
 
-      JSONPaths must be between < and > . Make sure that you dont use these symbols anywhere else.
+      JSONPaths must be between < and > . Make sure that you don't use these symbols anywhere else.
 
       Events generated by this possible Event Formatting Agent will look like:
 
@@ -35,7 +35,13 @@ module Agents
 
       If you want to retain original contents of events and only add new keys, then set `mode` to `merge`, otherwise set it to `clean`.
 
-      By default, the output event will have `agent` and `created_at` fields as well, reflecting the original Agent type and Event creation time.  You can skip these outputs by setting `skip_agent` and `skip_created_at` to `true`.
+      By default, the output event will have `agent` and `created_at` fields added as well, reflecting the original Agent type and Event creation time.  You can skip these outputs by setting `skip_agent` and `skip_created_at` to `true`.
+
+      To CGI escape output (for example when creating a link), prefix with `escape`, like so:
+
+          {
+            :message => "A peak was on Twitter in <$.group_by>.  Search: https://twitter.com/search?q=<escape $.group_by>"
+          }
     MD
 
     event_description <<-MD
@@ -62,7 +68,9 @@ module Agents
     end
 
     def value_constructor(value, payload)
-      value.gsub(/<[^>]+>/).each {|jsonpath| Utils.values_at(payload,jsonpath[1..-2]).first.to_s }
+      value.gsub(/<[^>]+>/).each { |jsonpath|
+        Utils.values_at(payload, jsonpath[1..-2]).first.to_s
+      }
     end
 
     def receive(incoming_events)

lib/utils.rb

@@ -1,4 +1,5 @@
 require 'jsonpath'
+require 'cgi'
 
 module Utils
   # Unindents if the indentation is 2 or more characters.
@@ -22,6 +23,18 @@ module Utils
   end
 
   def self.values_at(data, path)
-    JsonPath.new(path, :allow_eval => false).on(data.is_a?(String) ? data : data.to_json)
+    if path =~ /\Aescape /
+      path.gsub!(/\Aescape /, '')
+      escape = true
+    else
+      escape = false
+    end
+
+    result = JsonPath.new(path, :allow_eval => false).on(data.is_a?(String) ? data : data.to_json)
+    if escape
+      result.map {|r| CGI::escape r }
+    else
+      result
+    end
   end
 end

spec/lib/utils_spec.rb

@@ -24,5 +24,9 @@ describe Utils do
       Utils.values_at({ :foo => [ { :bar => :baz }, { :bar => :bing } ]}, "foo[*].bar").should == %w[baz bing]
       Utils.values_at({ :foo => [ { :bar => :baz }, { :bar => :bing } ]}, "foo[*].bar").should == %w[baz bing]
     end
+
+    it "should allow escaping" do
+      Utils.values_at({ :foo => { :bar => "escape this!?" }}, "escape $.foo.bar").should == ["escape+this%21%3F"]
+    end
   end
 end

spec/models/agents/event_formatting_agent_spec.rb

@@ -1,119 +1,128 @@
 require 'spec_helper'
 
 describe Agents::EventFormattingAgent do
-    before do
-        @valid_params = {
-            :name => "somename",
-            :options => {
-                :instructions => {
-                    :message => "Received <$.content.text.*> from <$.content.name> .",
-                    :subject => "Weather looks like <$.conditions>"
-                },
-                :mode => "clean",
-                :skip_agent => "false",
-                :skip_created_at => "false"
-            }
-        }
-        @checker = Agents::EventFormattingAgent.new(@valid_params)
-        @checker.user = users(:jane)
-        @checker.save!
-
-        @event = Event.new
-        @event.agent = agents(:jane_weather_agent)
-        @event.created_at = Time.now
-        @event.payload = {
-            :content => {
-                :text => "Some Lorem Ipsum",
-                :name => "somevalue"
+  before do
+    @valid_params = {
+        :name => "somename",
+        :options => {
+            :instructions => {
+                :message => "Received <$.content.text.*> from <$.content.name> .",
+                :subject => "Weather looks like <$.conditions>"
             },
-            :conditions => "someothervalue" 
+            :mode => "clean",
+            :skip_agent => "false",
+            :skip_created_at => "false"
         }
+    }
+    @checker = Agents::EventFormattingAgent.new(@valid_params)
+    @checker.user = users(:jane)
+    @checker.save!
+
+    @event = Event.new
+    @event.agent = agents(:jane_weather_agent)
+    @event.created_at = Time.now
+    @event.payload = {
+        :content => {
+            :text => "Some Lorem Ipsum",
+            :name => "somevalue"
+        },
+        :conditions => "someothervalue"
+    }
+  end
+
+  describe "#receive" do
+    it "should accept clean mode" do
+      @checker.receive([@event])
+      Event.last.payload[:content].should == nil
     end
 
-    describe "#receive" do
-        it "checks if clean mode is working fine" do
-            @checker.receive([@event])
-            Event.last.payload[:content].should == nil
-        end
-
-        it "checks if merge mode is working fine" do
-            @checker.options[:mode] = "merge"
-            @checker.receive([@event])
-            Event.last.payload[:content].should_not == nil
-        end
-
-        it "checks if skip_agent is working fine" do
-            @checker.receive([@event])
-            Event.last.payload[:agent].should == "WeatherAgent"
-            @checker.options[:skip_agent] = "true"
-            @checker.receive([@event])
-            Event.last.payload[:agent].should == nil
-        end
-
-        it "checks if skip_created_at is working fine" do
-            @checker.receive([@event])
-            Event.last.payload[:created_at].should_not == nil
-            @checker.options[:skip_created_at] = "true"
-            @checker.receive([@event])
-            Event.last.payload[:created_at].should == nil
-        end
-
-        it "checks if instructions are working fine" do
-            @checker.receive([@event])
-            Event.last.payload[:message].should == "Received Some Lorem Ipsum from somevalue ."
-            Event.last.payload[:subject].should == "Weather looks like someothervalue"
-        end
-
-        it "checks if it can handle multiple events" do
-            event1 = Event.new
-            event1.agent = agents(:bob_weather_agent)
-            event1.payload =  {
-            :content => {
-                :text => "Some Lorem Ipsum",
-                :name => "somevalue"
-                },
-            :conditions => "someothervalue" 
-            }
-
-            event2 = Event.new
-            event2.agent = agents(:bob_weather_agent)
-            event2.payload =  {
-            :content => {
-                :text => "Some Lorem Ipsum",
-                :name => "somevalue"
-                },
-            :conditions => "someothervalue" 
-            }
-
-        lambda {
-            @checker.receive([event2,event1])
-        }.should change { Event.count }.by(2)
-        end 
+    it "should accept merge mode" do
+      @checker.options[:mode] = "merge"
+      @checker.receive([@event])
+      Event.last.payload[:content].should_not == nil
     end
 
-    describe "validation" do
-        before do
-            @checker.should be_valid
-        end
-
-        it "should validate presence of instructions" do
-            @checker.options[:instructions] = ""
-            @checker.should_not be_valid
-        end
-
-        it "should validate presence of mode" do
-            @checker.options[:mode] = ""
-            @checker.should_not be_valid
-        end
-
-        it "should validate presence of skip_agent" do
-            @checker.options[:skip_agent] = ""
-            @checker.should_not be_valid
-        end
-
-        it "should validate presence of skip_created_at" do
-            @checker.options[:skip_created_at] = ""
-            @checker.should_not be_valid
-        end
+    it "should accept skip_agent" do
+      @checker.receive([@event])
+      Event.last.payload[:agent].should == "WeatherAgent"
+      @checker.options[:skip_agent] = "true"
+      @checker.receive([@event])
+      Event.last.payload[:agent].should == nil
     end
+
+    it "should accept skip_created_at" do
+      @checker.receive([@event])
+      Event.last.payload[:created_at].should_not == nil
+      @checker.options[:skip_created_at] = "true"
+      @checker.receive([@event])
+      Event.last.payload[:created_at].should == nil
+    end
+
+    it "should handle JSONPaths in instructions" do
+      @checker.receive([@event])
+      Event.last.payload[:message].should == "Received Some Lorem Ipsum from somevalue ."
+      Event.last.payload[:subject].should == "Weather looks like someothervalue"
+    end
+
+    it "should allow escaping" do
+      @event.payload[:content][:name] = "escape this!?"
+      @event.save!
+      @checker.options[:instructions][:message] = "Escaped: <escape $.content.name>\nNot escaped: <$.content.name>"
+      @checker.save!
+      @checker.receive([@event])
+      Event.last.payload[:message].should == "Escaped: escape+this%21%3F\nNot escaped: escape this!?"
+    end
+
+    it "should handle multiple events" do
+      event1 = Event.new
+      event1.agent = agents(:bob_weather_agent)
+      event1.payload = {
+          :content => {
+              :text => "Some Lorem Ipsum",
+              :name => "somevalue"
+          },
+          :conditions => "someothervalue"
+      }
+
+      event2 = Event.new
+      event2.agent = agents(:bob_weather_agent)
+      event2.payload = {
+          :content => {
+              :text => "Some Lorem Ipsum",
+              :name => "somevalue"
+          },
+          :conditions => "someothervalue"
+      }
+
+      lambda {
+        @checker.receive([event2, event1])
+      }.should change { Event.count }.by(2)
+    end
+  end
+
+  describe "validation" do
+    before do
+      @checker.should be_valid
+    end
+
+    it "should validate presence of instructions" do
+      @checker.options[:instructions] = ""
+      @checker.should_not be_valid
+    end
+
+    it "should validate presence of mode" do
+      @checker.options[:mode] = ""
+      @checker.should_not be_valid
+    end
+
+    it "should validate presence of skip_agent" do
+      @checker.options[:skip_agent] = ""
+      @checker.should_not be_valid
+    end
+
+    it "should validate presence of skip_created_at" do
+      @checker.options[:skip_created_at] = ""
+      @checker.should_not be_valid
+    end
+  end
 end