My child table data disappears after a few seconds

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1

Context:

I’m working on implementing a custom approval trail (sub-workflow) for a DocType using a custom API. The sub-workflow is supposed to kick in once the document reaches the Pending state (i.e., after it is submitted).

I’ve created a custom function create_approval_trail(doc, approvers, preserve_history=False) that appends entries to a child table field called approval_trail. It works fine initially — the table gets populated with approver data correctly.

Issue:

After submitting the document and entering the Pending state:

  • The approval_trail child table gets populated (as expected).
  • But within a few seconds, the entries disappear — the table becomes empty again.
  • There is no error in the UI or console, but the child table does not persist the data.

Expected Behavior:

  • Once the document is submitted and enters the Pending state,
  • The approval_trail child table should remain populated with the list of approvers until the document is either approved or rejected.

Current Workflow States:

  • Draft (initial)
  • Pending (starts sub-workflow / approval trail)
  • Approve
  • Reject

Code Overview:

Here’s the core part of the create_approval_trail function:

python

CopyEdit

def create_approval_trail(doc, approvers, preserve_history=False):
    if not preserve_history:
        doc.approval_trail = []
    else:
        doc.approval_trail.append({
            'status': 'Resubmitted',
            'comments': 'Document resubmitted with changes',
            ...
        })

    for approver in approvers:
        user = get_approver_user(approver, doc)
        if user:
            doc.append('approval_trail', {
                'user': user,
                'status': 'Pending',
                ...
            })

What I’ve Checked:

  • The data is definitely being appended to doc.approval_trail.
  • The code runs during the transition from Draft → Pending.
  • I suspect something is resetting or overwriting the child table data post-submit (maybe another before_save or on_update_after_submit?).

Question:

  • Why is my approval_trail child table data disappearing after a few seconds?
  • Could this be related to the timing of the workflow state transition vs document save/submit events?
  • Do I need to explicitly doc.save() or doc.db_update() somewhere after appending to the child table?

Let me know if you need my full hook or method trace.

Child Table Fields Not Updating
2

Table Data disappear video (Loom link)

3

Hey,

on which hook you are calling this create_approval_trail?

  • check your network tab, does any API calling which is returning empty child list.
  • On your hook print on first line when this method is actually calling. Is it calling twice?
4

Well this worked for me for now

doc.save()

Complete code

def create_approval_trail(doc, approvers, preserve_history=False):
    if not preserve_history:
        doc.approval_trail = []
    else:
        doc.approval_trail.append({
            'status': 'Resubmitted',
            'comments': 'Document resubmitted with changes',
            ...
        })

    for approver in approvers:
        user = get_approver_user(approver, doc)
        if user:
            doc.append('approval_trail', {
                'user': user,
                'status': 'Pending',
                ...
            })
  doc.save()