Cost center and creditor account from the ERP

Your ERP knows each vendor’s cost center and creditor account. The script asks it for the invoice’s vendor through the data source erp and sets both fields, which the workflow declares itself. When the ERP doesn’t know the vendor (status 404) or doesn’t answer, the script attaches a hint to the approval so the invoice is allocated by hand; a failed call doesn’t end the run.

The workflow

The workflow starts for every document of the type incoming-invoice. Its file workflow.yaml:

$schema: 'https://docs.acriva.de/schemas/workflow.schema.json'
format: 1
schemaVersion: 4
sdk: '1.0.0'
key: erp-cost-center
name: Kostenstelle und Kreditorenkonto aus dem ERP
template: custom
trigger:
  documentType: incoming-invoice
fields:
  - key: costCenter
    kind: text
    labelDe: Kostenstelle
    labelEn: Cost center
    documentTypes:
      - incoming-invoice
  - key: creditorAccount
    kind: text
    labelDe: Kreditorenkonto
    labelEn: Creditor account
    documentTypes:
      - incoming-invoice
start: allocate
steps:
  - kind: script
    name: allocate
    label: Kontierung aus dem ERP
    script: allocate.ts
    hook: onDocumentArrived
    inputs:
      - kind: field
        key: vendorName
        type: text
      - kind: source
        key: erp
    returns: []
    exits: []
    next: approve
  - kind: humanTask
    name: approve
    label: Freigabe
    taskKind: approve
    assignees:
      - when: null
        assignee:
          kind: costCenterResponsible
    fallback:
      kind: role
      role: Buchhaltung
    options:
      excludeRequester: true
      excludeActorsOfSteps: []
      pickFile: false
    next: approved
    onRejected: rejected
  - kind: end
    name: approved
    label: Freigegeben
    outcome: approved
  - kind: end
    name: rejected
    label: Zurückgewiesen
    outcome: rejected

The script allocate.ts

Hook: onDocumentArrived · Inputs: vendorName, data source erp · Return values: none

import { defineScript } from '@acriva/workflow-sdk';

/** What the ERP answers to `GET lieferanten?name=…`: the vendor's cost center and its creditor account. */
interface ErpVendor {
  kostenstelle: string;
  kreditorenkonto: string;
}

/** A source's answer is JSON of any shape until the script has checked it. */
const isErpVendor = (data: unknown): data is ErpVendor =>
  typeof data === 'object' &&
  data !== null &&
  typeof (data as ErpVendor).kostenstelle === 'string' &&
  typeof (data as ErpVendor).kreditorenkonto === 'string';

export default defineScript({
  hook: 'onDocumentArrived',
  async run(ctx) {
    const vendor = ctx.document.fields.vendorName;
    if (vendor == null) return;
    const result = await ctx.sources.get('erp', { path: 'lieferanten', query: { name: vendor } });
    // A failed call is a result, not an exception: the invoice is then allocated by hand.
    if (!result.ok) {
      ctx.hint(
        result.status === 404
          ? `„${vendor}“ ist im ERP nicht angelegt. Bitte kontieren Sie die Rechnung von Hand.`
          : `Das ERP hat nicht geantwortet (${result.error}). Bitte kontieren Sie die Rechnung von Hand.`,
      );
      return;
    }
    if (!isErpVendor(result.data)) {
      ctx.hint(
        'Das ERP hat keine Kostenstelle geliefert. Bitte kontieren Sie die Rechnung von Hand.',
      );
      return;
    }
    ctx.setField('costCenter', result.data.kostenstelle);
    ctx.setField('creditorAccount', result.data.kreditorenkonto);
  },
});

What it does

A test runs each of these cases in the sandbox and compares the result.

The ERP doesn’t answer

• Input: vendorName Bürobedarf Schmidt KG
• Data source erp: no data: timeout
• Exit: the default next step
• Changes: hint on the next task: “Das ERP hat nicht geantwortet (timeout). Bitte kontieren Sie die Rechnung von Hand.”

A vendor the ERP knows

• Input: vendorName Telekom Deutschland GmbH
• Data source erp: answers {"kostenstelle":"4400","kreditorenkonto":"70012"}
• Exit: the default next step
• Changes: field costCenter = 4400; field creditorAccount = 70012

A vendor the ERP doesn’t know

• Input: vendorName Neue Firma AG
• Data source erp: no data: http-error (status 404)
• Exit: the default next step
• Changes: hint on the next task: “„Neue Firma AG“ ist im ERP nicht angelegt. Bitte kontieren Sie die Rechnung von Hand.”