Include full blob key in Azure read operations exceptions

plugins/repository-azure/src/internalClusterTest/java/org/elasticsearch/repositories/azure/AzureBlobStoreRepositoryTests.java

@@ -30,6 +30,7 @@
 
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
+import java.nio.file.NoSuchFileException;
 import java.util.ArrayList;
 import java.util.Base64;
 import java.util.Collection;
@@ -40,6 +41,7 @@
 import java.util.regex.Pattern;
 
 import static org.hamcrest.Matchers.anEmptyMap;
+import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.is;
 
 @SuppressForbidden(reason = "this test uses a HttpServer to emulate an Azure endpoint")
@@ -243,4 +245,12 @@ public void testDeleteBlobsIgnoringIfNotExists() throws Exception {
             assertThat(container.listBlobs(), is(anEmptyMap()));
         }
     }
+
+    public void testNotFoundErrorMessageContainsFullKey() throws Exception {
+        try (BlobStore store = newBlobStore()) {
+            BlobContainer container = store.blobContainer(BlobPath.EMPTY.add("nested").add("dir"));
+            NoSuchFileException exception = expectThrows(NoSuchFileException.class, () -> container.readBlob("blob"));
+            assertThat(exception.getMessage(), equalTo("Blob [nested/dir/blob] not found"));
+        }
+    }
 }

plugins/repository-azure/src/main/java/org/elasticsearch/repositories/azure/AzureBlobContainer.java

@@ -47,6 +47,7 @@ public boolean blobExists(String blobName) throws IOException {
     }
 
     private InputStream openInputStream(String blobName, long position, @Nullable Long length) throws IOException {
+        String blobKey = buildKey(blobName);
         logger.trace("readBlob({}) from position [{}] with length [{}]", blobName, position, length != null ? length : "unlimited");
         if (blobStore.getLocationMode() == LocationMode.SECONDARY_ONLY && blobExists(blobName) == false) {
             // On Azure, if the location path is a secondary location, and the blob does not
@@ -55,18 +56,18 @@ private InputStream openInputStream(String blobName, long position, @Nullable Lo
             // before throwing a storage exception.  This can cause long delays in retrieving
             // snapshots, so we first check if the blob exists before trying to open an input
             // stream to it.
-            throw new NoSuchFileException("Blob [" + blobName + "] does not exist");
+            throw new NoSuchFileException("Blob [" + blobKey + "] not found");
         }
         try {
-            return blobStore.getInputStream(buildKey(blobName), position, length);
+            return blobStore.getInputStream(blobKey, position, length);
         } catch (Exception e) {
             Throwable rootCause = Throwables.getRootCause(e);
             if (rootCause instanceof BlobStorageException) {
                 if (((BlobStorageException) rootCause).getStatusCode() == 404) {
-                    throw new NoSuchFileException("Blob [" + blobName + "] not found");
+                    throw new NoSuchFileException("Blob [" + blobKey + "] not found");
                 }
             }
-            throw new IOException("Unable to get input stream for blob [" + blobName + "]", e);
+            throw new IOException("Unable to get input stream for blob [" + blobKey + "]", e);
         }
     }