public com.google.protobuf.ByteString getCdnKeyIdBytes() {
      java.lang.Object ref = cdnKeyId_;
      if (ref instanceof String) {
        com.google.protobuf.ByteString b =
            com.google.protobuf.ByteString.copyFromUtf8((java.lang.String) ref);
        cdnKeyId_ = b;
        return b;
      } else {
        return (com.google.protobuf.ByteString) ref;
      }
    }
<pre>
Required. The ID to use for the CDN key, which will become the final
component of the CDN key's resource name.

This value should conform to RFC-1034, which restricts to
lower-case letters, numbers, and hyphen, with the first character a
letter, the last a letter or a number, and a 63 character maximum.
</pre>

<code>string cdn_key_id = 3 [(.google.api.field_behavior) = REQUIRED];</code>

@return The bytes for cdnKeyId.
java-video-stitcher/proto-google-cloud-video-stitcher-v1/src/main/java/com/google/cloud/video/stitcher/v1/CreateCdnKeyRequest.java