ZIP archive support for multiple YANG files delivery on Schema Set creation using REST

Issue-ID: CPS-180
Change-Id: I7e78a595593b170b981746e9aed1a7e5a45b202a
Signed-off-by: Ruslan Kashapov <ruslan.kashapov@pantheon.tech>

1 files changed, 79 insertions, 9 deletions

diff --git a/cps-rest/src/main/java/org/onap/cps/rest/utils/MultipartFileUtil.java b/cps-rest/src/main/java/org/onap/cps/rest/utils/MultipartFileUtil.java
index c53d1a42a..532a0ca84 100644
--- a/cps-rest/src/main/java/org/onap/cps/rest/utils/MultipartFileUtil.java
+++ b/cps-rest/src/main/java/org/onap/cps/rest/utils/MultipartFileUtil.java
@@ -19,13 +19,18 @@
 
 package org.onap.cps.rest.utils;
 
-import static com.google.common.base.Preconditions.checkNotNull;
 import static org.opendaylight.yangtools.yang.common.YangConstants.RFC6020_YANG_FILE_EXTENSION;
 
 import com.google.common.collect.ImmutableMap;
+import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.io.InputStream;
 import java.nio.charset.StandardCharsets;
+import java.util.Arrays;
+import java.util.Locale;
 import java.util.Map;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipInputStream;
 import lombok.AccessLevel;
 import lombok.NoArgsConstructor;
 import org.onap.cps.spi.exceptions.CpsException;
@@ -35,26 +40,81 @@ import org.springframework.web.multipart.MultipartFile;
 @NoArgsConstructor(access = AccessLevel.PRIVATE)
 public class MultipartFileUtil {
 
+    private static final String ZIP_FILE_EXTENSION = ".zip";
+    private static final String YANG_FILE_EXTENSION = RFC6020_YANG_FILE_EXTENSION;
+    private static final int READ_BUFFER_SIZE = 1024;
+
     /**
      * Extracts yang resources from multipart file instance.
      *
      * @param multipartFile the yang file uploaded
      * @return yang resources as {map} where the key is original file name, and the value is file content
-     * @throws ModelValidationException if the file name extension is not '.yang'
+     * @throws ModelValidationException if the file name extension is not '.yang' or '.zip'
+     *                                  or if zip archive contain no yang files
      * @throws CpsException             if the file content cannot be read
      */
 
     public static Map<String, String> extractYangResourcesMap(final MultipartFile multipartFile) {
-        return ImmutableMap.of(extractYangResourceName(multipartFile), extractYangResourceContent(multipartFile));
+        final String originalFileName = multipartFile.getOriginalFilename();
+        if (resourceNameEndsWithExtension(originalFileName, YANG_FILE_EXTENSION)) {
+            return ImmutableMap.of(originalFileName, extractYangResourceContent(multipartFile));
+        }
+        if (resourceNameEndsWithExtension(originalFileName, ZIP_FILE_EXTENSION)) {
+            return extractYangResourcesMapFromZipArchive(multipartFile);
+        }
+        throw new ModelValidationException("Unsupported file type.",
+            String.format("Filename %s matches none of expected extensions: %s", originalFileName,
+                Arrays.asList(YANG_FILE_EXTENSION, ZIP_FILE_EXTENSION)));
+    }
+
+    private static Map<String, String> extractYangResourcesMapFromZipArchive(final MultipartFile multipartFile) {
+        final ImmutableMap.Builder<String, String> yangResourceMapBuilder = ImmutableMap.builder();
+
+        try (
+            final InputStream inputStream = multipartFile.getInputStream();
+            final ZipInputStream zipInputStream = new ZipInputStream(inputStream);
+        ) {
+            ZipEntry zipEntry;
+            while ((zipEntry = zipInputStream.getNextEntry()) != null) {
+                extractZipEntryToMapIfApplicable(yangResourceMapBuilder, zipEntry, zipInputStream);
+            }
+            zipInputStream.closeEntry();
+
+        } catch (final IOException e) {
+            throw new CpsException("Cannot extract resources from zip archive.", e.getMessage(), e);
+        }
+
+        try {
+            final Map<String, String> yangResourceMap = yangResourceMapBuilder.build();
+            if (yangResourceMap.isEmpty()) {
+                throw new ModelValidationException("Archive contains no YANG resources.",
+                    String.format("Archive contains no files having %s extension.", YANG_FILE_EXTENSION));
+            }
+            return yangResourceMap;
+
+        } catch (final IllegalArgumentException e) {
+            throw new ModelValidationException("Invalid ZIP archive content.",
+                "Multiple resources with same name detected.", e);
+        }
     }
 
-    private static String extractYangResourceName(final MultipartFile multipartFile) {
-        final String fileName = checkNotNull(multipartFile.getOriginalFilename(), "Missing filename.");
-        if (!fileName.endsWith(RFC6020_YANG_FILE_EXTENSION)) {
-            throw new ModelValidationException("Unsupported file type.",
-                String.format("Filename %s does not end with '%s'", fileName, RFC6020_YANG_FILE_EXTENSION));
+    private static void extractZipEntryToMapIfApplicable(
+        final ImmutableMap.Builder<String, String> yangResourceMapBuilder, final ZipEntry zipEntry,
+        final ZipInputStream zipInputStream) throws IOException {
+
+        final String yangResourceName = extractResourceNameFromPath(zipEntry.getName());
+        if (zipEntry.isDirectory() || !resourceNameEndsWithExtension(yangResourceName, YANG_FILE_EXTENSION)) {
+            return;
         }
-        return fileName;
+        yangResourceMapBuilder.put(yangResourceName, extractYangResourceContent(zipInputStream));
+    }
+
+    private static boolean resourceNameEndsWithExtension(final String resourceName, final String extension) {
+        return resourceName != null && resourceName.toLowerCase(Locale.ENGLISH).endsWith(extension);
+    }
+
+    private static String extractResourceNameFromPath(final String path) {
+        return path == null ? "" : path.replaceAll("^.*[\\\\/]", "");
     }
 
     private static String extractYangResourceContent(final MultipartFile multipartFile) {
@@ -65,4 +125,14 @@ public class MultipartFileUtil {
         }
     }
 
+    private static String extractYangResourceContent(final ZipInputStream zipInputStream) throws IOException {
+        try (final ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream()) {
+            final byte[] buffer = new byte[READ_BUFFER_SIZE];
+            int numberOfBytesRead;
+            while ((numberOfBytesRead = zipInputStream.read(buffer, 0, READ_BUFFER_SIZE)) > 0) {
+                byteArrayOutputStream.write(buffer, 0, numberOfBytesRead);
+            }
+            return byteArrayOutputStream.toString(StandardCharsets.UTF_8);
+        }
+    }
 }