Ensure closing of InputStream resources (#111)

services/distribution/src/main/java/app/coronawarn/server/services/distribution/crypto/CryptoProvider.java

@@ -17,6 +17,7 @@
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
+import org.springframework.core.io.Resource;
 import org.springframework.core.io.ResourceLoader;
 import org.springframework.stereotype.Component;
 
@@ -72,9 +73,8 @@ private static Certificate getCertificateFromBytes(final byte[] bytes)
    */
   public PrivateKey getPrivateKey() {
     if (this.privateKey == null) {
-      try {
-        InputStream privateKeyStream = resourceLoader.getResource(privateKeyPath)
-            .getInputStream();
+      Resource privateKeyResource = resourceLoader.getResource(privateKeyPath);
+      try (InputStream privateKeyStream = privateKeyResource.getInputStream()) {
         this.privateKey = getPrivateKeyFromStream(privateKeyStream);
       } catch (IOException e) {
         logger.error("Failed to load private key from {}", privateKeyPath, e);
@@ -89,8 +89,8 @@ public PrivateKey getPrivateKey() {
    */
   public Certificate getCertificate() {
     if (this.certificate == null) {
-      try {
-        InputStream certStream = resourceLoader.getResource(certificatePath).getInputStream();
+      Resource certResource = resourceLoader.getResource(certificatePath);
+      try (InputStream certStream = certResource.getInputStream()) {
         this.certificate = getCertificateFromStream(certStream);
       } catch (IOException | CertificateException e) {
         logger.error("Failed to load certificate from {}", certificatePath, e);

services/distribution/src/main/java/app/coronawarn/server/services/distribution/exposureconfig/ExposureConfigurationProvider.java

@@ -6,6 +6,7 @@
 import java.io.IOException;
 import java.io.InputStream;
 import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.Resource;
 import org.yaml.snakeyaml.Yaml;
 import org.yaml.snakeyaml.error.YAMLException;
 import org.yaml.snakeyaml.introspector.BeanAccess;
@@ -47,7 +48,8 @@ public static RiskScoreParameters readFile(String path) throws UnableToLoadFileE
     Yaml yaml = new Yaml(new YamlConstructorForProtoBuf());
     yaml.setBeanAccess(BeanAccess.FIELD); /* no setters on RiskScoreParameters available */
 
-    try (InputStream inputStream = new ClassPathResource(path).getInputStream()) {
+    Resource riskScoreParametersResource = new ClassPathResource(path);
+    try (InputStream inputStream = riskScoreParametersResource.getInputStream()) {
       Builder loaded = yaml.loadAs(inputStream, RiskScoreParameters.newBuilder().getClass());
       if (loaded == null) {
         throw new UnableToLoadFileException(path);