fix: ensure headers can be set and overriden

README.md

@@ -19,6 +19,7 @@ This is an autogenerated Java SDK for OpenFGA. It provides a wrapper around the
 - [Installation](#installation)
 - [Getting Started](#getting-started)
   - [Initializing the API Client](#initializing-the-api-client)
+  - [Custom Headers](#custom-headers)
   - [Get your Store ID](#get-your-store-id)
   - [Calling the API](#calling-the-api)
     - [Stores](#stores)
@@ -236,6 +237,68 @@ public class Example {
 }
 ```
 
+### Custom Headers
+
+#### Default Headers
+
+You can set default headers to be sent with every request by using the `defaultHeaders` property of the `ClientConfiguration` class.
+
+```java
+import com.fasterxml.jackson.databind.ObjectMapper;
+import dev.openfga.sdk.api.client.OpenFgaClient;
+import dev.openfga.sdk.api.configuration.ClientConfiguration;
+
+import java.net.http.HttpClient;
+import java.util.Map;
+
+public class Example {
+    public static void main(String[] args) throws Exception {
+        var config = new ClientConfiguration()
+                .apiUrl(System.getenv("FGA_API_URL"))
+                .storeId(System.getenv("FGA_STORE_ID"))
+                .authorizationModelId(System.getenv("FGA_MODEL_ID"))
+                .defaultHeaders(Map.of(
+                        "X-Custom-Header", "default-value",
+                        "X-Request-Source", "my-app"
+                ));
+
+        var fgaClient = new OpenFgaClient(config);
+    }
+}
+```
+
+#### Per-request Headers
+
+You can set custom headers to be sent with a specific request by using the `additionalHeaders` property of the options classes (e.g. `ClientReadOptions`, `ClientWriteOptions`, etc.).
+
+```java
+import com.fasterxml.jackson.databind.ObjectMapper;
+import dev.openfga.sdk.api.client.OpenFgaClient;
+import dev.openfga.sdk.api.configuration.ClientConfiguration;
+import java.net.http.HttpClient;
+
+public class Example {
+    public static void main(String[] args) throws Exception {
+        var config = new ClientConfiguration()
+                .apiUrl(System.getenv("FGA_API_URL"))
+                .storeId(System.getenv("FGA_STORE_ID"))
+                .authorizationModelId(System.getenv("FGA_MODEL_ID"))
+                .defaultHeaders(Map.of(
+                        "X-Custom-Header", "default-value",
+                        "X-Request-Source", "my-app"
+                ));
+
+        var fgaClient = new OpenFgaClient(config);
+        var options = new ClientReadOptions()
+                    .additionalHeaders(Map.of(
+                            "X-Request-Id", "123e4567-e89b-12d3-a456-426614174000",
+                            "X-Custom-Header", "overridden-value" // this will override the default value for this request only
+                    )
+                );
+        var response = fgaClient.read(request, options).get();
+    }
+}
+```
 
 ### Get your Store ID
 

src/main/java/dev/openfga/sdk/api/client/OpenFgaClient.java

@@ -248,7 +248,13 @@ public CompletableFuture<ClientReadAuthorizationModelResponse> readAuthorization
             ClientReadAuthorizationModelOptions options) throws FgaInvalidParameterException {
         configuration.assertValid();
         String storeId = configuration.getStoreIdChecked();
-        String authorizationModelId = options.getAuthorizationModelIdChecked();
+        // Set authorizationModelId from options if available; otherwise, require a valid configuration value
+        String authorizationModelId;
+        if (options != null && !isNullOrWhitespace(options.getAuthorizationModelId())) {
+            authorizationModelId = options.getAuthorizationModelIdChecked();
+        } else {
+            authorizationModelId = configuration.getAuthorizationModelIdChecked();
+        }
         var overrides = new ConfigurationOverride().addHeaders(options);
         return call(() -> api.readAuthorizationModel(storeId, authorizationModelId, overrides))
                 .thenApply(ClientReadAuthorizationModelResponse::new);
@@ -552,12 +558,12 @@ private CompletableFuture<ClientWriteResponse> writeNonTransaction(
                 ? writeOptions
                 : new ClientWriteOptions().transactionChunkSize(DEFAULT_MAX_METHOD_PARALLEL_REQS);
 
-        if (options.getAdditionalHeaders() == null) {
-            options.additionalHeaders(new HashMap<>());
-        }
-        options.getAdditionalHeaders().putIfAbsent(CLIENT_METHOD_HEADER, "Write");
-        options.getAdditionalHeaders()
-                .putIfAbsent(CLIENT_BULK_REQUEST_ID_HEADER, randomUUID().toString());
+        HashMap<String, String> headers = options.getAdditionalHeaders() != null
+                ? new HashMap<>(options.getAdditionalHeaders())
+                : new HashMap<>();
+        headers.putIfAbsent(CLIENT_METHOD_HEADER, "Write");
+        headers.putIfAbsent(CLIENT_BULK_REQUEST_ID_HEADER, randomUUID().toString());
+        options.additionalHeaders(headers);
 
         int chunkSize = options.getTransactionChunkSize();
 
@@ -832,12 +838,13 @@ public CompletableFuture<List<ClientBatchCheckClientResponse>> clientBatchCheck(
         var options = batchCheckOptions != null
                 ? batchCheckOptions
                 : new ClientBatchCheckClientOptions().maxParallelRequests(DEFAULT_MAX_METHOD_PARALLEL_REQS);
-        if (options.getAdditionalHeaders() == null) {
-            options.additionalHeaders(new HashMap<>());
-        }
-        options.getAdditionalHeaders().putIfAbsent(CLIENT_METHOD_HEADER, "ClientBatchCheck");
-        options.getAdditionalHeaders()
-                .putIfAbsent(CLIENT_BULK_REQUEST_ID_HEADER, randomUUID().toString());
+
+        HashMap<String, String> headers = options.getAdditionalHeaders() != null
+                ? new HashMap<>(options.getAdditionalHeaders())
+                : new HashMap<>();
+        headers.putIfAbsent(CLIENT_METHOD_HEADER, "ClientBatchCheck");
+        headers.putIfAbsent(CLIENT_BULK_REQUEST_ID_HEADER, randomUUID().toString());
+        options.additionalHeaders(headers);
 
         int maxParallelRequests = options.getMaxParallelRequests() != null
                 ? options.getMaxParallelRequests()
@@ -892,12 +899,13 @@ public CompletableFuture<ClientBatchCheckResponse> batchCheck(
                 : new ClientBatchCheckOptions()
                         .maxParallelRequests(DEFAULT_MAX_METHOD_PARALLEL_REQS)
                         .maxBatchSize(DEFAULT_MAX_BATCH_SIZE);
-        if (options.getAdditionalHeaders() == null) {
-            options.additionalHeaders(new HashMap<>());
-        }
-        options.getAdditionalHeaders().putIfAbsent(CLIENT_METHOD_HEADER, "BatchCheck");
-        options.getAdditionalHeaders()
-                .putIfAbsent(CLIENT_BULK_REQUEST_ID_HEADER, randomUUID().toString());
+
+        HashMap<String, String> headers = options.getAdditionalHeaders() != null
+                ? new HashMap<>(options.getAdditionalHeaders())
+                : new HashMap<>();
+        headers.putIfAbsent(CLIENT_METHOD_HEADER, "BatchCheck");
+        headers.putIfAbsent(CLIENT_BULK_REQUEST_ID_HEADER, randomUUID().toString());
+        options.additionalHeaders(headers);
 
         Map<String, ClientBatchCheckItem> correlationIdToCheck = new HashMap<>();
 
@@ -1124,12 +1132,13 @@ public CompletableFuture<ClientListRelationsResponse> listRelations(
         var options = listRelationsOptions != null
                 ? listRelationsOptions
                 : new ClientListRelationsOptions().maxParallelRequests(DEFAULT_MAX_METHOD_PARALLEL_REQS);
-        if (options.getAdditionalHeaders() == null) {
-            options.additionalHeaders(new HashMap<>());
-        }
-        options.getAdditionalHeaders().putIfAbsent(CLIENT_METHOD_HEADER, "ListRelations");
-        options.getAdditionalHeaders()
-                .putIfAbsent(CLIENT_BULK_REQUEST_ID_HEADER, randomUUID().toString());
+
+        HashMap<String, String> headers = options.getAdditionalHeaders() != null
+                ? new HashMap<>(options.getAdditionalHeaders())
+                : new HashMap<>();
+        headers.putIfAbsent(CLIENT_METHOD_HEADER, "ListRelations");
+        headers.putIfAbsent(CLIENT_BULK_REQUEST_ID_HEADER, randomUUID().toString());
+        options.additionalHeaders(headers);
 
         var batchCheckRequests = request.getRelations().stream()
                 .map(relation -> new ClientCheckRequest()

src/main/java/dev/openfga/sdk/api/configuration/ClientBatchCheckClientOptions.java

@@ -13,6 +13,7 @@
 package dev.openfga.sdk.api.configuration;
 
 import dev.openfga.sdk.api.model.ConsistencyPreference;
+import java.util.HashMap;
 import java.util.Map;
 
 public class ClientBatchCheckClientOptions implements AdditionalHeadersSupplier {
@@ -60,7 +61,7 @@ public ConsistencyPreference getConsistency() {
 
     public ClientCheckOptions asClientCheckOptions() {
         return new ClientCheckOptions()
-                .additionalHeaders(additionalHeaders)
+                .additionalHeaders(additionalHeaders != null ? new HashMap<>(additionalHeaders) : null)
                 .authorizationModelId(authorizationModelId)
                 .consistency(consistency);
     }

src/main/java/dev/openfga/sdk/api/configuration/ClientConfiguration.java

@@ -140,4 +140,10 @@ public ClientConfiguration telemetryConfiguration(TelemetryConfiguration telemet
         super.telemetryConfiguration(telemetryConfiguration);
         return this;
     }
+
+    @Override
+    public ClientConfiguration defaultHeaders(java.util.Map<String, String> defaultHeaders) {
+        super.defaultHeaders(defaultHeaders);
+        return this;
+    }
 }

src/main/java/dev/openfga/sdk/api/configuration/ClientListRelationsOptions.java

@@ -13,6 +13,7 @@
 package dev.openfga.sdk.api.configuration;
 
 import dev.openfga.sdk.api.model.ConsistencyPreference;
+import java.util.HashMap;
 import java.util.Map;
 
 public class ClientListRelationsOptions implements AdditionalHeadersSupplier {
@@ -61,6 +62,7 @@ public ConsistencyPreference getConsistency() {
     public ClientBatchCheckClientOptions asClientBatchCheckClientOptions() {
         return new ClientBatchCheckClientOptions()
                 .authorizationModelId(authorizationModelId)
+                .additionalHeaders(additionalHeaders != null ? new HashMap<>(additionalHeaders) : null)
                 .maxParallelRequests(maxParallelRequests)
                 .consistency(consistency);
     }