Welcome to the world of MicroStation Python! In our previous wikis, we delved into creating, attaching, and detaching Item Types. Now, let us take it a step further. In this wiki, you will learn how to update the "RoomDetails" Item Type values from a JSON file hosted on a web server.

To set up a local JSON server, refer to this comprehensive tutorial: Set Up JSON Server

Update Item Type

To get started, refer to the Python Manager wiki for instructions on creating and loading a new Python project. Name your project "ItemType_UpdateItem.py" and save it in a convenient location. Once created, open the project in your preferred code editor to begin writing your Python script.

The script retrieves the 'RoomDetails' values from a JSON server, scans the DGN file for Shape elements, and updates the attached Item Types with the fetched values.

We use the requests library to retrieve the 'RoomDetails' values from a JSON server. To install the requests library, open a command prompt (CMD.exe), navigate to the folder C:\ProgramData\Bentley\PowerPlatformPython\python\, and key-in “python -m pip install requests”.

Here is the complete script.

import requests
from MSPyBentley import *
from MSPyBentleyGeom import *
from MSPyECObjects import *
from MSPyDgnPlatform import *
from MSPyMstnPlatform import *
from MSPyDgnView import *

g_room_data_dict = []


# Get data from dictionary.
def getRoomData(room_id):
    return next((room for room in g_room_data_dict if room["room_id"] == room_id), None)


# Scan Room Shapes
def scanRoomsUpdateData():
    dgnFile = ISessionMgr.GetActiveDgnFile()
    if dgnFile is None:
        return False

    dgnModel = ISessionMgr.ActiveDgnModel
    if dgnModel is None:
        return False

    graphicalElements = dgnModel.GetGraphicElements()

    for elmRef in graphicalElements:
        eeh = EditElementHandle(elmRef, dgnModel)

        msElement = eeh.GetElement()
        isGraphics = msElement.ehdr.isGraphics
        isVisible = not(msElement.hdr.dhdr.props.b.invisible)
        eleType = eeh.GetElementType()

        if (isGraphics and isVisible and eleType == 6):
            itemHost = CustomItemHost(eeh, False)
            if (itemHost == None):
                print ("itemHost is null...")
                return False
                
            dgnecinstance_0 = itemHost.GetCustomItem("Project_001", "RoomDetails")
            if (dgnecinstance_0 == None):
                print ("dgnecinstance_0 is null...")
                return False

            if None == dgnecinstance_0:
                print ('ERROR in retrieving item type from element...\n')
            else:
                # Update Data here
                propValue = ECValue()
                dgnecinstance_0.GetValue(propValue, 'ID')
                #print('Room ID :' + str(propValue.GetInteger()) + '\n')

                r_id = propValue.GetInteger()
                room_info = getRoomData(r_id)
                #print (room_info)

                dgnecinstance_0.SetValue('Description', ECValue(room_info["description"]))

                date_string = room_info["date_time"]
                date_part, time_part = date_string.split()
                MO, DD, YY = date_part.split('-')
                HH, MM = time_part.split(':')
                SS = 0
                updateDate = BeDateTime (BeDateTime.Kind.eUnspecified, int(YY), 
                                         int(MO), int(DD), int(HH), int(MM), SS)
                dgnecinstance_0.SetValue('Date', ECValue(updateDate))

                temp = float(room_info["temperature"])
                dgnecinstance_0.SetValue('Temperature', ECValue(temp))        

                humi = float(room_info["humidity"])        
                dgnecinstance_0.SetValue('Humidity', ECValue(humi))    

                occ = int(room_info["occupied"])
                if (occ == 1):
                    dgnecinstance_0.SetValue('Occupied', ECValue(True, occ))
                else:
                    dgnecinstance_0.SetValue('Occupied', ECValue(False, occ))

                dgnecinstance_0.WriteChanges()

    print ("Data updated to elements...")

    return True


# Get Data from Server
def getDataFromServer():
    global g_room_data_dict

    url = 'http://localhost:8000/RoomDetails'

    try:
        response = requests.get(url)
        response.raise_for_status()

        #print ("Response Code : ")
        #print (response.status_code)
    
        if response.status_code == 404:
            print("Page Not found...")
            return False
        elif response.status_code == 500:
            print("Internal server error...")
            return False
        elif response.status_code == 200:
            data = response.json()

            if isinstance(data, list):
                print("*** Room Details ***")

            for item in data:
                new_room = {"room_id": item["room_id"], "description": item["description"], 
                            "temperature": item["temperature"], "humidity": item["humidity"], 
                            "date_time": item["date_time"], "occupied": item["occupied"]}
                g_room_data_dict.append(new_room)
                #print (new_room)

            pass
        else:
            print("Other error...")
            #return False
    except requests.exceptions.ConnectionError as e:
        print("Server Connection error...", e)
        return False
    except requests.exceptions.Timeout as e:
        print("Server Request timed out...", e)
        return False
    except requests.exceptions.RequestException as e:
        print("Server Request error...", e)
        return False

    return True


# Main function
def main():
    PyCadInputQueue.SendKeyin("set view wireframe; selview all")

    if (True != getDataFromServer()):
        print ("Data extraction failed...")
    else:
        print ("Data extracted from local JSON server...")
        if (True == scanRoomsUpdateData()):
            print ("Applying Display Style...")
            PyCadInputQueue.SendKeyin("Change view custom RoomTempThematic 1; selview all")


# Main
if __name__ == "__main__":
    print ("**** Update Item Type values from Server/JSON ****")

    main()

Run/Execute project

Load the project “ItemType_UpdateItem.py” from the Python Manager dialog and Run/Execute the python script.

Download “RoomDetails” JSON file, “Building_Update.dgn” DGN file.

Item Type “RoomDetails” values are updated to all Shape elements as illustrated below.

Before

After

A display style is applied to add color to the Temperature values.

Happy coding!

MicroStation Python: Update Item Type

Run/Execute project