Latest Contributions by JohnDye

According to this post by RJ Sunderman‌, when you Poll ArcGIS Server for Features and use the Get Incremental Updates method, the input will maintain an in-memory cache. Is there anyway to query this cache to determine what the underlying deltas are? In my case, I want to create a GeoEvent service that will poll a Feature Service for updates every 5 minutes. When it determines that updates have been made to the service (one or more features have been added, one or more features have been edited, or some combination of the two), I want it to actually compare the returned features to its in-memory cache and compile the actual changes so that they can be written as a new feature to a "Change-Log" feature service. If there is not a way to query that in-memory cache (which is my expectation), is there another way for us to determine what the nature of the changes are? We want very granular tracking of every single change made to certain services. We explored using SOIs for this and that was successful to an extent, but the lack of support for Hosted Services has become a show stopper since we're trying very hard to move away from Federated Services. ... View more

Does anyone have an example of what the addField method in the FieldInfo class does? The documentation on it is not particularly helpful. I was wondering if it might be a very efficient method to add a field to a feature layer. ... View more

I was slapping together a toolbox tool today and came across an interesting issue. import arcpy class Toolbox(object):     def __init__(self):         """Define the toolbox (the name of the toolbox is the name of the         .pyt file)."""         self.label = "Toolbox"         self.alias = ""         # List of tool classes associated with this toolbox         self.tools = [Tool] class Tool(object):     def __init__(self):         """Define the tool (tool name is the name of the class)."""         self.label = "Tool"         self.description = ""         self.canRunInBackground = False     def MessageBox(self, Title, Message, ButtonStyle=0, MessageboxType="NOICON"):         """         Raises a system-modal messagebox with the given title and message         with the specified ButtonStyle and MessageboxType. Used to raise         messageboxes from a Python Toolbox tool operating on a Background Thread.         INPUTS:             Title (String)                 Title of the messagebox             Message (String)                 Message to be displayed in the messagebox             ButtonStyle (Integer)                 Value:                   Buttons Shown:                 0                        OK (Default)                 1                        OK | Cancel                 2                        Abort | Retry | Ignore                 3                        Yes | No | Cancel                 4                        Yes | No                 5                        Retry | No                 6                        Cancel | Try Again | Continue             MessageboxType (String)                 Value:                   Description:                 NOICON                   No icon is displayed in the Messagebox                 INFO                     An Information Icon is displayed                 QUESTION                 A Question Mark Icon is displayed                 WARNING                  A Warning Icon is displayed                 ERROR                    An Error Icon is displayed         OUTPUTS:             Button Clicked (Integer)                 Value returned indicates the buttonpressed by the user                 Return Value             Button Pressed                 1                        OK                 2                        Cancel                 3                        Abort                 4                        Retry                 5                        Ignore                 6                        Yes                 7                        No                 10                       Try Again                 11                       Continue         """         if MessageboxType == "NOICON":             MB_STYLE = 0x00         elif MessageboxType == "INFO":             MB_STYLE = 0x40         elif MessageboxType == "QUESTION":             MB_STYLE = 0x20         elif MessageboxType == "WARNING":             MB_STYLE = 0x30         elif MessageboxType == "ERROR":             MB_STYLE = 0x10         else:             raise Exception("Invalid 'MessageboxType' value")         if ButtonStyle not in range(0, 7):             raise Exception("Invalid 'ButtonStyle' value")         import ctypes         buttonPressed = ctypes.windll.user32.MessageBoxA(0                                             , Message                                             , Title                                             , ButtonStyle | MB_STYLE | 0x40000)         return buttonPressed     def getParameterInfo(self):         """Define parameter definitions"""         param0 = arcpy.Parameter(             displayName="Input Features",             name="in_features",             datatype="GPString",             parameterType="Required",             direction="Input")         param0.filter.type="ValueList"         param0.filter.list=["Butter", "Milk", "Bread"]         params = [param0]         return params     def isLicensed(self):         """Set whether tool is licensed to execute."""         return True     def updateParameters(self, parameters):         """Modify the values and properties of parameters before internal         validation is performed.  This method is called whenever a parameter         has been changed."""         if parameters[0].value:             self.MessageBox("Selected Parameter", parameters[0].valueAsText)         return     def updateMessages(self, parameters):         """Modify the messages created by internal validation for each tool         parameter.  This method is called after internal validation."""         return     def execute(self, parameters, messages):         """The source code of the tool."""         arcpy.AddMessage("Parameter 0: " + parameters[0].valueAsText)         return ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ There's nothing crazy going on here. Only thing out of the ordinary is that MessageBox function. Here's the weird thing. My updateParameters function has some logic to raise a Messagebox that displays the value selected by the user in param0. Works fine except that for some reason, the value is being sliced - I'm only getting the first letter of the selected parameter. I also added an AddMessage function to the execute function to print the selected parameter to the Results Window. That actually gives me the full value, so perhaps it is my Messagebox function that is slicing it but I don't think so. Anyone have any insight? ... View more