Overview

This node integrates with the SAP Service Layer API to manage various purchase-related entities, including Purchase Tax Invoices. Specifically, for the "Purchase Tax Invoice" resource and the "Get by Key" operation, it retrieves a single purchase tax invoice identified by its unique key (DocEntry). This is useful when you need to fetch detailed information about a specific purchase tax invoice from SAP Business One.

Common scenarios:

• Retrieving details of a particular purchase tax invoice for review or processing.
• Integrating SAP purchase tax invoice data into other systems or workflows.
• Automating reporting or validation tasks that require exact invoice data.

Practical example:
You want to get the full details of a purchase tax invoice with DocEntry 12345 to verify its amounts and tax codes before approving payment.

Properties

Output

The node outputs JSON data representing the purchase tax invoice object as returned by the SAP Service Layer API. This includes all fields and nested objects related to the invoice, such as vendor details, line items, totals, taxes, and status.

If the operation uses $select (not in this case), only specified fields would be returned.

The node does not output binary data.

Dependencies

• Requires an API key credential or authentication credentials for the SAP Service Layer API, including:

  • Base URL of the SAP Service Layer endpoint.
  • Username and password for authentication.
  • Company database name.

• The node performs a login request to obtain session cookies used for subsequent API calls.

• The SAP Service Layer must be accessible from the n8n environment.

Troubleshooting

• Authentication errors: If login fails, check the correctness of the username, password, company DB, and network connectivity to the SAP Service Layer.

• Invalid DocEntry: If the specified DocEntry does not exist, the API will return an error. Verify the ID is correct.

• Network issues: Timeouts or connection errors may occur if the SAP Service Layer is unreachable.

• Permission issues: Ensure the user has sufficient permissions to read purchase tax invoices.

• Error messages: The node returns error messages from the API in the output JSON under an error field. Review these messages for clues.

Links and References

• SAP Business One Service Layer Documentation
• OData Query Options (for $select, $filter usage)

Summary of execute() logic for Resource "Purchase Tax Invoice" and Operation "Get by Key"

• Authenticates to SAP Service Layer via POST /Login with provided credentials.
• Extracts session cookies from login response.
• Constructs a GET request to /PurchaseTaxInvoices({DocEntry}) where {DocEntry} is the input number.
• Sends the request with session cookies.
• Returns the JSON response from SAP as the node output.
• Handles errors by returning them in the output JSON.