feat(odata): support v1 element template variable format

[vringar]

Summary

Adds backward compatibility so the OData connector can process variables sent by v1 (pre-batch) element templates in addition to the current v2 format. Both the v2 task type (with fallback detection) and the legacy v1 task type are supported.

Problem

The v1 element template sends variables in a flat structure (destination, oDataService, entityOrEntitySet, httpMethod.*, payload) without the requestDetails.requestType discriminator that the v2 connector expects. When context.bindVariables(ODataConnectorRequest.class) receives v1 input, it silently sets requestDetails = null, causing runtime failures downstream.

Additionally, some customer deployments use the legacy task type io.camunda:sap:odata:outbound: (with trailing colon) which no v2 worker listens for.

Approach

Two complementary mechanisms ensure v1 templates work regardless of which task type they use:

1. Fallback in ODataConnector (type io.camunda:sap-odata:2): After binding, if requestDetails is null, the connector re-binds using FallbackODataConnectorRequest and converts to a standard request. This catches v1 templates that happen to target the v2 task type.

2. LegacyODataConnector (type io.camunda:sap:odata:outbound:): A separate connector class registered via SPI that directly binds flat v1 variables through FallbackODataConnectorRequest and delegates to ODataRequestExecutor.

Changes

File	Change
FallbackODataConnectorRequest.java	New — fallback model with validation (@NotEmpty, @Pattern, @Valid) and conversion to ODataConnectorRequest
LegacyODataConnector.java	New — connector worker for legacy task type io.camunda:sap:odata:outbound:
ODataConnector.java	Modified — fallback detection when requestDetails is null after binding
OutboundConnectorFunction (SPI)	Modified — added LegacyODataConnector to service loader
pom.xml	Modified — added Lombok annotation processor path (required for Java 22+ on release/8.7)
s4-v1-get.bpmn	New — example BPMN with v1 flat variable structure for testing
BaseTest.java	New — JSON test case loader
OutboundBaseTest.java	New — connector context builder helper
HotfixBindingTest.java	New — 3 parameterized tests for binding and conversion
hotfix.json	New — test fixture with v1 variable structure

Testing

Unit tests

3 parameterized tests in HotfixBindingTest:

1. Proves ODataConnectorRequest binding produces requestDetails = null for v1 input (documents the problem)
2. Proves FallbackODataConnectorRequest binding succeeds with typed HttpMethod instances
3. Proves toODataConnectorRequest() correctly converts fallback → canonical request

E2E validation on BTP (SaaS 8.7 cluster)

• v2 task type with v1 variables: Deployed s4-v1-get.bpmn (task type io.camunda:sap-odata:2, flat variables). Logs confirmed fallback triggered and OData request constructed correctly.
• Legacy task type: Deployed BPMN with task type io.camunda:sap:odata:outbound:. LegacyODataConnector picked up the job, bound flat variables, and executed the OData request successfully.

[Copilot]

Pull request overview

Adds backward compatibility to the SAP OData connector so it can handle the legacy v1 (pre-batch) element template variable shape where requestDetails.requestType is missing, by rebinding via a fallback model and converting to the current request format.

Changes:

• Introduces FallbackODataConnectorRequest to bind the v1 flat variable structure and convert it to ODataConnectorRequest (wrapping a SimpleRequest).
• Updates ODataConnector.execute() to detect requestDetails == null and re-bind using the fallback model (with an INFO log when used).
• Adds test infrastructure + fixture (hotfix.json) and new binding tests covering the legacy input shape.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
odata-connector/src/main/java/io/camunda/connector/sap/odata/model/FallbackODataConnectorRequest.java	New fallback request record with validation annotations and conversion to the v2 request structure.
odata-connector/src/main/java/io/camunda/connector/sap/odata/ODataConnector.java	Adds runtime fallback re-binding when v1 inputs cause requestDetails to deserialize as null.
odata-connector/src/test/java/io/camunda/connector/sap/odata/BaseTest.java	New shared test helper for loading JSON test cases as strings.
odata-connector/src/test/java/io/camunda/connector/sap/odata/OutboundBaseTest.java	New helper for creating an OutboundConnectorContextBuilder with secrets.
odata-connector/src/test/java/io/camunda/connector/sap/odata/HotfixBindingTest.java	New parameterized tests documenting the binding issue and validating fallback binding + conversion.
odata-connector/src/test/resources/hotfix.json	New legacy-input fixture used by the binding tests.

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