chore: added crc to upload part

Author: ShreyasSinha

google-cloud-storage/src/main/java/com/google/cloud/storage/ChecksumResponseParser.java

@@ -22,19 +22,21 @@
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.List;
 import java.util.Map;
-import java.util.Optional;
 import java.util.stream.Collectors;
 
-/** A utility class to parse {@link HttpResponse} and create a {@link UploadPartResponse}. */
+/** A utility class to parse checksums from an {@link HttpResponse}. */
 final class ChecksumResponseParser {
 
+  private static final String X_GOOG_HASH = "x-goog-hash";
+
   private ChecksumResponseParser() {}
 
   static UploadPartResponse parseUploadResponse(HttpResponse response) {
     String eTag = response.getHeaders().getETag();
     Map<String, String> hashes = extractHashesFromHeader(response);
-    return UploadPartResponse.builder().eTag(eTag).md5(hashes.get("md5")).build();
+    return UploadPartResponse.builder().eTag(eTag).md5(hashes.get("md5")).crc32c(hashes.get("crc32c")).build();
   }
 
   static CompleteMultipartUploadResponse parseCompleteResponse(HttpResponse response)
@@ -52,14 +54,18 @@ static CompleteMultipartUploadResponse parseCompleteResponse(HttpResponse respon
   }
 
   static Map<String, String> extractHashesFromHeader(HttpResponse response) {
-    return Optional.ofNullable(response.getHeaders().getFirstHeaderStringValue("x-goog-hash"))
-        .map(
-            h ->
-                Arrays.stream(h.split(","))
-                    .map(s -> s.trim().split("=", 2))
-                    .filter(a -> a.length == 2)
-                    .filter(a -> "crc32c".equalsIgnoreCase(a[0]) || "md5".equalsIgnoreCase(a[0]))
-                    .collect(Collectors.toMap(a -> a[0].toLowerCase(), a -> a[1], (v1, v2) -> v1)))
-        .orElse(Collections.emptyMap());
+    List<String> hashHeaders = response.getHeaders().getHeaderStringValues(X_GOOG_HASH);
+    if (hashHeaders == null || hashHeaders.isEmpty()) {
+      return Collections.emptyMap();
+    }
+
+    return hashHeaders.stream()
+        .flatMap(h -> Arrays.stream(h.split(",")))
+        .map(String::trim)
+        .filter(s -> !s.isEmpty())
+        .map(s -> s.split("=", 2))
+        .filter(a -> a.length == 2)
+        .filter(a -> "crc32c".equalsIgnoreCase(a[0]) || "md5".equalsIgnoreCase(a[0]))
+        .collect(Collectors.toMap(a -> a[0].toLowerCase(), a -> a[1], (v1, v2) -> v1));
   }
 }

google-cloud-storage/src/main/java/com/google/cloud/storage/multipartupload/model/UploadPartResponse.java

@@ -31,10 +31,12 @@ public final class UploadPartResponse {
 
   private final String eTag;
   private final String md5;
+  private final String crc32c;
 
   private UploadPartResponse(Builder builder) {
     this.eTag = builder.etag;
     this.md5 = builder.md5;
+    this.crc32c = builder.crc32c;
   }
 
   /**
@@ -59,6 +61,17 @@ public String md5() {
     return md5;
   }
 
+  /**
+   * Returns the CRC32C checksum of the uploaded part.
+   *
+   * @return The CRC32C checksum.
+   * @since 2.60.0 This new api is in preview and is subject to breaking changes.
+   */
+  @BetaApi
+  public String crc32c() {
+    return crc32c;
+  }
+
   @Override
   public boolean equals(Object o) {
     if (this == o) {
@@ -68,17 +81,23 @@ public boolean equals(Object o) {
       return false;
     }
     UploadPartResponse that = (UploadPartResponse) o;
-    return Objects.equals(eTag, that.eTag) && Objects.equals(md5, that.md5);
+    return Objects.equals(eTag, that.eTag)
+        && Objects.equals(md5, that.md5)
+        && Objects.equals(crc32c, that.crc32c);
   }
 
   @Override
   public int hashCode() {
-    return Objects.hash(eTag, md5);
+    return Objects.hash(eTag, md5, crc32c);
   }
 
   @Override
   public String toString() {
-    return MoreObjects.toStringHelper(this).add("etag", eTag).add("md5", md5).toString();
+    return MoreObjects.toStringHelper(this)
+        .add("etag", eTag)
+        .add("md5", md5)
+        .add("crc32c", crc32c)
+        .toString();
   }
 
   /**
@@ -101,6 +120,7 @@ public static Builder builder() {
   public static class Builder {
     private String etag;
     private String md5;
+    private String crc32c;
 
     private Builder() {}
 
@@ -130,6 +150,19 @@ public Builder md5(String md5) {
       return this;
     }
 
+    /**
+     * Sets the CRC32C checksum for the uploaded part.
+     *
+     * @param crc32c The CRC32C checksum.
+     * @return This builder.
+     * @since 2.60.0 This new api is in preview and is subject to breaking changes.
+     */
+    @BetaApi
+    public Builder crc32c(String crc32c) {
+      this.crc32c = crc32c;
+      return this;
+    }
+
     /**
      * Builds the {@code UploadPartResponse} object.
      *