Only Log Concurrency Warning Message when AWS_LAMBDA_MAX_CONCURRENCY is set (#90)

* Only Log Concurrency Warning Message when AWS_LAMBDA_MAX_CONCURRENCY is set * Var name change --------- Co-authored-by: Mohammed Ehab <moehabe@amazon.com>

Author: M-Elsaeed

aws-lambda-java-runtime-interface-client/src/main/java/com/amazonaws/services/lambda/runtime/api/client/util/ConcurrencyConfig.java

@@ -22,14 +22,23 @@ public ConcurrencyConfig(LambdaContextLogger logger) {
  public ConcurrencyConfig(LambdaContextLogger logger, EnvReader envReader) {
  int readNumOfPlatformThreads = 0;
  try {
- readNumOfPlatformThreads = Integer.parseInt(envReader.getEnv(ReservedRuntimeEnvironmentVariables.AWS_LAMBDA_MAX_CONCURRENCY));
- if (readNumOfPlatformThreads <= 0 || readNumOfPlatformThreads > AWS_LAMBDA_MAX_CONCURRENCY_LIMIT) {
- throw new IllegalArgumentException();
+ String readLambdaMaxConcurrencyEnvVar = envReader.getEnv(ReservedRuntimeEnvironmentVariables.AWS_LAMBDA_MAX_CONCURRENCY);
+
+ // Log only if env var is actually set to an invalid value. Otherwise default to no concurrency silently.
+ if (!(readLambdaMaxConcurrencyEnvVar == null || readLambdaMaxConcurrencyEnvVar.isEmpty())) {
+ readNumOfPlatformThreads = Integer.parseInt(readLambdaMaxConcurrencyEnvVar);
+ if (readNumOfPlatformThreads <= 0 || readNumOfPlatformThreads > AWS_LAMBDA_MAX_CONCURRENCY_LIMIT) {
+ throw new IllegalArgumentException();
+ }
  }
  } catch (Exception e) {
- String message = String.format("User configured %s is not valid. Please make sure it is a positive number more than zero and less than or equal %d\n%s\nDefaulting to no concurrency.", ReservedRuntimeEnvironmentVariables.AWS_LAMBDA_MAX_CONCURRENCY, AWS_LAMBDA_MAX_CONCURRENCY_LIMIT, UserFault.trace(e));
- logger.log(message, logger.getLogFormat() == LogFormat.JSON ? LogLevel.WARN : LogLevel.UNDEFINED);
  readNumOfPlatformThreads = 0;
+ String message = String.format(
+ "User configured %s is not valid. Please make sure it is a positive number more than zero and less than or equal %d\n%s\nDefaulting to no concurrency.",
+ ReservedRuntimeEnvironmentVariables.AWS_LAMBDA_MAX_CONCURRENCY,
+ AWS_LAMBDA_MAX_CONCURRENCY_LIMIT,
+ UserFault.trace(e));
+ logger.log(message, logger.getLogFormat() == LogFormat.JSON ? LogLevel.WARN : LogLevel.UNDEFINED);
  }
 
  this.numberOfPlatformThreads = readNumOfPlatformThreads;

aws-lambda-java-runtime-interface-client/src/test/java/com/amazonaws/services/lambda/runtime/api/client/util/ConcurrencyConfigTest.java

@@ -29,10 +29,10 @@ class ConcurrencyConfigTest {
 
  @Test
  void testDefaultConfiguration() {
- when(lambdaLogger.getLogFormat()).thenReturn(LogFormat.JSON);
  when(envReader.getEnv(ReservedRuntimeEnvironmentVariables.AWS_LAMBDA_MAX_CONCURRENCY)).thenReturn(null);
 
  ConcurrencyConfig config = new ConcurrencyConfig(lambdaLogger, envReader);
+ verifyNoInteractions(lambdaLogger);
  assertEquals(0, config.getNumberOfPlatformThreads());
  assertEquals(false, config.isMultiConcurrent());
  }