Checklist

• I have looked into the README and have not found a suitable solution or answer.
• I have looked into the documentation and have not found a suitable solution or answer.
• I have searched the issues and have not found a suitable solution or answer.
• I have upgraded to the latest version of OpenFGA and the issue still persists.
• I have searched the Slack community and have not found a suitable solution or answer.
• I agree to the terms within the OpenFGA Code of Conduct.

Description

Summary

Response headers are not being returned in ClientWriteResponse objects for write operations when using transaction mode (the default).

Impact

• Affected versions: v0.9.0, v0.9.1, v0.9.2
• Affected operations: All write operations in transaction mode:
  • write()
  • writeTuples()
  • deleteTuples()

Root Cause

When non-transaction write support was added in v0.9.0, the ClientWriteResponse class added a constructor that hardcodes empty headers:

File: src/main/java/dev/openfga/sdk/api/client/model/ClientWriteResponse.java
Line: 24

public ClientWriteResponse(List<ClientWriteSingleResponse> writes, List<ClientWriteSingleResponse> deletes) {
    this.statusCode = 200;
    this.headers = Collections.emptyMap(); // ❌ Headers hardcoded to empty map
    this.rawResponse = "";
    this.writes = writes != null ? writes : Collections.emptyList();
    this.deletes = deletes != null ? deletes : Collections.emptyList();
}

This constructor is appropriate for non-transaction mode, which aggregates results from multiple API calls. However, it's also being used by OpenFgaClient.writeTransactions() at line ~510, which makes a single API call and should preserve the headers from that response.

Expectation

Expected Behavior

Write operations should return response headers in ClientWriteResponse, allowing users to access HTTP response metadata.

Actual Behavior

response.getHeaders() returns an empty map {} for all write operations in transaction mode.

Reproduction

Sample:

ClientWriteRequest request = new ClientWriteRequest()
    .writes(List.of(new ClientTupleKey()
        .user("user:anne")
        .relation("reader")
        ._object("document:budget")));

ClientWriteResponse response = fgaClient.write(request).get();
Map<String, List<String>> headers = response.getHeaders();
System.out.println(headers); // Prints: {}

OpenFGA SDK version

0.9.2

OpenFGA version

N/A (affects all versions)

SDK Configuration

Standard ClientConfiguration initialization - bug is not configuration-dependent

Logs

No response

References

Additional Context

• The bug was introduced in v0.9.0 (released Aug 15, 2025)
• The issue occurs in multiple locations where ClientWriteResponseis constructed:
  • Line ~510 in writeTransactions() (transaction mode)
  • Line ~656 in writeNonTransaction() (non-transaction mode)
  • Line ~713 in writeTuples()
  • Line ~759 in deleteTuples()
• This does not affect read operations, check operations, or other client methods that correctly preserve headers