19. Manual scenario selection and branch merging

Let the operator approve or reject a set of requests and return to a shared export after the selected action.

Task and prerequisites

Let the operator approve or reject a set of requests and return to a shared export after the selected action.

This example uses demonstration data and settings. Validate the expected result in your own environment before connecting production destinations. Identifiers demo_* are illustrative: select your own training connections or sources in the editor. The JSON below shows the block and connection structure, not a ready-to-transfer flow archive.

Training input data

requests.csv

Request;Status
R1;Draft
R2;Draft

Blocks, connections and exact settings

19. Manual scenario selection and branch merging. Example 19 topology: 6 blocks, 6 connections. Node identifiers and ports from the configured graph are preserved. — **Flow diagram 19**
Example 19 topology: 6 blocks, 6 connections. Node identifiers and ports from the configured graph are preserved.

Add the listed blocks in the designer, open each block's properties and set these values. Names demo_* identify training sources and connections.

Block	Setting
1 File `src`	Role: `source` Source: `demo_approval` Read settings: Sheet: `CSV` Range: `A1:B3` First row is the header: `так` Delimiter: `;`
2 Choice `choice`	Title: `Рішення щодо набору заявок` Read settings: Identifier: `approve` Label: `Погодити` Identifier: `reject` Label: `Відхилити` wizard: `так`
3 Set field values `approved`	assignments: Field: `Status` Source: `constant` Value type: `text` Value: `Approved`
4 Set field values `rejected`	assignments: Field: `Status` Source: `constant` Value type: `text` Value: `Rejected`
5 Merge branches `merge`	Inputs: Identifier: `approved` Label: `Погоджено` Identifier: `rejected` Label: `Відхилено` Mode: `single`
6 Data export `out`	Format: `csv` File name: `decisions` Purpose: `download` Delimiter: `;` Time zone: `Europe/Kyiv`

Port connections

src out → choice in
choice approve → approved in
choice reject → rejected in
approved out → merge approved
rejected out → merge rejected
merge out → out in

Complete graph configuration as JSON

{
  "version": 3,
  "nodes": [
    {
      "id": "src",
      "type": "file",
      "label": "src",
      "config": {
        "role": "source",
        "source_id": "demo_approval",
        "options": {
          "sheet": "CSV",
          "range": "A1:B3",
          "header": true,
          "delimiter": ";"
        }
      }
    },
    {
      "id": "choice",
      "type": "choice",
      "label": "choice",
      "config": {
        "title": "Рішення щодо набору заявок",
        "options": [
          {
            "id": "approve",
            "label": "Погодити"
          },
          {
            "id": "reject",
            "label": "Відхилити"
          }
        ],
        "wizard": true
      }
    },
    {
      "id": "approved",
      "type": "set_fields",
      "label": "approved",
      "config": {
        "assignments": [
          {
            "field": "Status",
            "source": "constant",
            "value_type": "text",
            "value": "Approved"
          }
        ]
      }
    },
    {
      "id": "rejected",
      "type": "set_fields",
      "label": "rejected",
      "config": {
        "assignments": [
          {
            "field": "Status",
            "source": "constant",
            "value_type": "text",
            "value": "Rejected"
          }
        ]
      }
    },
    {
      "id": "merge",
      "type": "merge",
      "label": "merge",
      "config": {
        "inputs": [
          {
            "id": "approved",
            "label": "Погоджено"
          },
          {
            "id": "rejected",
            "label": "Відхилено"
          }
        ],
        "mode": "single"
      }
    },
    {
      "id": "out",
      "type": "export",
      "label": "out",
      "config": {
        "format": "csv",
        "filename": "decisions",
        "destination": "download",
        "delimiter": ";",
        "timezone": "Europe/Kyiv"
      }
    }
  ],
  "edges": [
    {
      "source": "src",
      "target": "choice",
      "source_port": "out",
      "target_port": "in"
    },
    {
      "source": "choice",
      "target": "approved",
      "source_port": "approve",
      "target_port": "in"
    },
    {
      "source": "choice",
      "target": "rejected",
      "source_port": "reject",
      "target_port": "in"
    },
    {
      "source": "approved",
      "target": "merge",
      "source_port": "out",
      "target_port": "approved"
    },
    {
      "source": "rejected",
      "target": "merge",
      "source_port": "out",
      "target_port": "rejected"
    },
    {
      "source": "merge",
      "target": "out",
      "source_port": "out",
      "target_port": "in"
    }
  ]
}

Expected result

After selecting “Approve”, decisions.csv contains R1/Approved and R2/Approved; the rejected branch is skipped. After selecting “Reject”, both statuses are Rejected. This is one decision for the entire input dataset.

Run and verify

Run the flow interactively and select “Approve”.
Verify two updated requests, one active branch and a successful merge.
Run again with “Reject” and verify both Rejected statuses.

Common errors

Choice always requires a user response; it is unsuitable for unattended execution.
Merge single expects one active branch; use Union to append two tables simultaneously.
Do not confuse a manual choice of one scenario with Router, which distributes rows according to conditions.