Element owned elements recipe

Learn how to retrieve owned elements programmatically. Each recipe includes a detailed explanation, step-by-step instructions, and sample code.

Recipes covered:

1. Get owned elements

This example demonstrates how to recursively navigate through the hierarchical structure of elements by using the SysON API. The script starts from a specific element identified by its ID and retrieves its details along with any "owned elements." The function calls itself recursively to explore all child elements in the hierarchy, printing their names, IDs, and types in an indented format to show the hierarchy visually.

Example script to get owned elements:

get_owned_element.py
# These examples are adapted from the SysML v2 API Cookbook, available at
# https://github.com/Systems-Modeling/SysML-v2-API-Cookbook, maintained by the
# Object Management Group (OMG).
# The original cookbook is designed for use with Jupyter Lab.
# These examples have been adapted to run as standalone Python scripts, making
# them suitable for use in various environments, including SysON.
# They showcase practical usage scenarios and may include additional functionality
# or modifications tailored to specific needs.

import requests
from init_api import parse_arguments
from init_api import init_sysmlv2_api
from fetch_commits import get_last_commit_id

# Function to fetch an element and print its name and type
def get_element(host, project_id, commit_id, element_id, indent):
     # Fetch the element in the given commit of the given project
    element_url = f"{host}/projects/{project_id}/commits/{commit_id}/elements/{element_id}"  (3)
    response = requests.get(element_url)  (1)

    if response.status_code == 200:
        element_data = response.json()
        element_name_to_print = element_data['name'] if element_data['name'] else 'N/A'
        element_id = element_data ['@id']
        element_type = element_data ['@type']
        print(f"{indent} - {element_name_to_print} (id = {element_id} , type = {element_type})") (2)
        return element_data
    else:
        return None

# Fetches immediate owned elements for a given element
def get_owned_elements_immediate(host, project_id, commit_id, element_id, indent):
    element_data = get_element(host, project_id, commit_id, element_id, indent)
    if element_data:
        owned_elements = element_data['ownedElement']
        if len(owned_elements) > 0:
            for owned_element in owned_elements:
                get_element(host, project_id, commit_id, owned_element['@id'], indent + '  ')
    else:
        print(f"Unable to fetch element with id '{element_id}' in commit '{commit_id}' of project '{project_id}'")

# Fetches owned elements recursively for a given element
def get_owned_elements(host, project_id, commit_id, element_id, indent):
    element_data = get_element(host, project_id, commit_id, element_id, indent)
    if element_data: (3)
        owned_elements = element_data['ownedElement']
        if len(owned_elements) > 0:
            for owned_element in owned_elements:
                get_owned_elements(host, project_id, commit_id, owned_element['@id'], indent+' ')
    else:
        print(f"Unable to fetch element with id '{element_id}' in commit '{commit_id}' of project '{project_id}'")  (4)

if __name__ == "__main__":
    args = parse_arguments()
    host = init_sysmlv2_api()
    project_id = args.project_id
    commit_id = get_last_commit_id(host, project_id)
    element_id = args.element_id

    #Get owned elements (immediate) for the given element in the given commit of the given project
    print("Immediate Owned Elements:")
    get_owned_elements_immediate(host, project_id, commit_id, element_id, '')

    # Get owned elements (recursive) for the given element in the given commit of the given project
    print("\nRecursive Owned Elements:")
    get_owned_elements(host, project_id, commit_id, element_id, '')

What this code does:

1 Fetches an Element: Sends a GET request to the SysON API to retrieve details about an element specified by its ID.
2 Prints Element Details: Displays the element’s name, ID, and type in a formatted, indented way.
3 Processes Owned Elements: Checks for owned elements and calls itself recursively for each one.
4 Recursive Traversal: Continues recursing through hierarchical levels until it explores and prints all owned elements.

This approach helps visualize the structure of complex models or systems, where elements are organized hierarchically. It highlights how to navigate relationships between elements efficiently by using the SysON API.

Run the script:

$ python get_owned_elements.py

Output example:

Commit ID: 63a03bd8-a81a-4818-801a-01790ce8a086
Last Commit ID: 63a03bd8-a81a-4818-801a-01790ce8a086
Immediate Owned Elements:
 - Batmobile (Definition)
   - problemStatement (ReferenceUsage)
   - systemIdea (ReferenceUsage)
   - seat (PartUsage)
   - body (PartUsage)
   - wheels (PartUsage)
   - frontLeftWheel (PartUsage)
   - frontRightWheel (PartUsage)
   - rearLeftWheel (PartUsage)
   - rearRightWheel (PartUsage)
   - battery (PartUsage)
   - batmobileEngine (PartUsage)

Recursive Owned Elements:
 - Batmobile (Definition)
  - problemStatement (ReferenceUsage)
   - N/A (LiteralString)
  - systemIdea (ReferenceUsage)
   - N/A (LiteralString)
  - seat (PartUsage)
  - body (PartUsage)
  - wheels (PartUsage)
  - frontLeftWheel (PartUsage)
  - frontRightWheel (PartUsage)
  - rearLeftWheel (PartUsage)
  - rearRightWheel (PartUsage)
  - battery (PartUsage)
   - powerPort (PortUsage)
   - capacity (AttributeUsage)
  - batmobileEngine (PartUsage)
   - enginePort (PortUsage)