fix filter bug + test (#72)

* fix filter bug + test

Author: EItanya

source/extensions/filters/http/aws_lambda/aws_lambda_filter.cc

@@ -83,7 +83,7 @@ AWSLambdaFilter::decodeHeaders(Http::RequestHeaderMap &headers,
     secret_key = &protocol_options_->secretKey().value();
     // attempt to set session_token, ok if nil
     if (protocol_options_->sessionToken().has_value()) {
-      session_token = &protocol_options_->secretKey().value();
+      session_token = &protocol_options_->sessionToken().value();
     }
   } else if (filter_config_) {
     credentials_ = filter_config_->getCredentials();

test/extensions/filters/http/aws_lambda/aws_lambda_filter_test.cc

@@ -131,7 +131,7 @@ TEST_F(AWSLambdaFilterTest, SignsOnHeadersEndStreamWithToken) {
 
   // Check aws headers.
   EXPECT_TRUE(headers.has("Authorization"));
-  EXPECT_TRUE(headers.has(AwsAuthenticatorConsts::get().SecurityTokenHeader));
+  EXPECT_EQ(headers.get(AwsAuthenticatorConsts::get().SecurityTokenHeader)->value(), "session token");
 }
 
 TEST_F(AWSLambdaFilterTest, SignsOnHeadersEndStreamWithConfig) {
@@ -160,7 +160,7 @@ TEST_F(AWSLambdaFilterTest, SignsOnHeadersEndStreamWithConfigWithToken) {
   EXPECT_TRUE(filter_config_->called_);
   // Check aws headers.
   EXPECT_TRUE(headers.has("Authorization"));
-  EXPECT_TRUE(headers.has(AwsAuthenticatorConsts::get().SecurityTokenHeader));
+  EXPECT_EQ(headers.get(AwsAuthenticatorConsts::get().SecurityTokenHeader)->value(), "session token");
 }
 
 TEST_F(AWSLambdaFilterTest, SignsOnHeadersEndStreamWithBadConfig) {