fix: no null minRetry value allowed

Author: jimmyjames

CHANGELOG.md

@@ -6,10 +6,13 @@
 - feat: RFC 9110 compliant Retry-After header support with exponential backoff and jitter
 - feat: Enhanced retry strategy with delay calculation
 - feat: Retry-After header value exposed in error objects for better observability
+- feat: Input validation for Configuration.minimumRetryDelay() to prevent negative values
+- feat: Default value (100ms) now explicitly set for minimumRetryDelay configuration
 
 ### Changed
 - **BREAKING**: Maximum allowable retry count is now enforced at 15 (default remains 3)
 - **BREAKING**: FgaError now exposes Retry-After header value via getRetryAfterHeader() method
+- **BREAKING**: Configuration.minimumRetryDelay() now requires non-null values and validates input, throwing IllegalArgumentException for null or negative values
 
 ### Technical Details
 - Implements RFC 9110 compliant Retry-After header parsing (supports both integer seconds and HTTP-date formats)
@@ -21,6 +24,7 @@
 **Migration Guide**: 
 - Update error handling code if using FgaError properties - new getRetryAfterHeader() method available
 - Note: Maximum allowable retries is now enforced at 15 (validation added to prevent exceeding this limit)
+- **IMPORTANT**: Configuration.minimumRetryDelay() now requires non-null values and validates input - ensure you're not passing null or negative Duration values, as this will now throw IllegalArgumentException. Previously null values were silently accepted and would fall back to default behavior at runtime.
 
 ## v0.8.3
 

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

@@ -289,18 +289,26 @@ public Integer getMaxRetries() {
     /**
      * Sets the minimum delay to wait before retrying a failed request.
      *
-     * @param minimumRetryDelay The minimum delay. Must be non-negative.
+     * @param minimumRetryDelay The minimum delay. Must be non-null and non-negative.
      * @return This Configuration instance for method chaining.
-     * @throws IllegalArgumentException if minimumRetryDelay is negative.
+     * @throws IllegalArgumentException if minimumRetryDelay is null or negative.
      */
     public Configuration minimumRetryDelay(Duration minimumRetryDelay) {
-        if (minimumRetryDelay != null && minimumRetryDelay.isNegative()) {
+        if (minimumRetryDelay == null) {
+            throw new IllegalArgumentException("minimumRetryDelay cannot be null");
+        }
+        if (minimumRetryDelay.isNegative()) {
             throw new IllegalArgumentException("minimumRetryDelay cannot be negative");
         }
         this.minimumRetryDelay = minimumRetryDelay;
         return this;
     }
 
+    /**
+     * Gets the minimum delay to wait before retrying a failed request.
+     *
+     * @return The minimum retry delay. Never null.
+     */
     @Override
     public Duration getMinimumRetryDelay() {
         return minimumRetryDelay;

src/test/java/dev/openfga/sdk/api/configuration/ConfigurationTest.java

@@ -295,12 +295,12 @@ void minimumRetryDelay_nullValue() {
         // Given
         Configuration config = new Configuration();
 
-        // When
-        Configuration result = config.minimumRetryDelay(null);
+        // When & Then
+        IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> {
+            config.minimumRetryDelay(null);
+        });
 
-        // Then
-        assertNull(result.getMinimumRetryDelay());
-        assertSame(config, result, "Should return the same Configuration instance for method chaining");
+        assertEquals("minimumRetryDelay cannot be null", exception.getMessage());
     }
 
     @Test