[Bug]: Diagram editor unable to connect output from sections to other nodes/sections

[DillonChew98]

Before proceeding, is there an existing issue or discussion for this?

• I have done a search for similar issues and discussions.

OS and version

Ubuntu 22.04

Open-RMF installation type

Source build

Other Open-RMF installation methods

No response

Open-RMF version or commit hash

f95003c

ROS distribution

Humble

ROS installation type

Source build

Other ROS installation methods

No response

Package or library, if applicable

No response

Description of the bug

Description

Currently there is an issue where it is not possible to connect the output of a defined section to another node/section. This only happens when trying to wire the sections on the UI. Loading up a diagram with predefined connections has no issue.

Link to example diagrams. The wiredup.json contains the fully wired up and working workflow while the bug.json contains the half wired up workflow with the impossible connection.

This seems to be an issue with only the main branch. Tested this with the live demo, which should be on 0.0.6(?) and it works as intended.

Steps to reproduce the bug

1. Create either 2 sections (Can be empty or defined) or 1 node 1 section
2. Try to connect the output from one section to the other

Expected behavior

Sections are able to connect to each other directly and the diagram gets executed.

main branch workflow:

live_demo workflow:

Actual behavior

Section outputs cannot connect directly to other nodes/sections. Have to manually alter the connect field in the diagram.json file

Additional information or screenshots

No response

[ArizmendiWan]

Thank you so much for opening this issue! My understanding is that this is an editor-side validation problem. Newly drawn connections were not automatically selecting the section’s existing named ports, leaving the compatibility check without the port information that a pre-wired diagram already provides.

The proposed fix selects section ports automatically when the choice is unambiguous, and treats unresolved type information as unknown rather than incompatible. This allows unfinished sections to be connected.

Steps to verify

1. Build and open the calculator editor from the fix/compatibility branch.
2. Load bug.json from your example diagrams.
3. Drag from the output of the section using the multiply template to the input of add_section.
4. The connection should now be accepted, with new_output and new_input selected automatically—no manual JSON changes needed.
5. Run the workflow with numeric input 2. The expected result is 15 (2 × 5 + 5), matching the behaviour of wiredup.json.