/**
 * # File Append
 * A transaction body message to append data to a "file" in state.
 *
 * ### Keywords
 * The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
 * "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
 * document are to be interpreted as described in
 * [RFC2119](https://www.ietf.org/rfc/rfc2119) and clarified in
 * [RFC8174](https://www.ietf.org/rfc/rfc8174).
 */
syntax = "proto3";

package proto;

// SPDX-License-Identifier: Apache-2.0
option java_package = "com.hederahashgraph.api.proto.java";
// <<<pbj.java_package = "com.hedera.hapi.node.file">>> This comment is special code for setting PBJ Compiler java package
option java_multiple_files = true;

import "services/basic_types.proto";

/**
 * A transaction body for an `appendContent` transaction.<br/>
 * This transaction body provides a mechanism to append content to a "file" in
 * network state. Hedera transactions are limited in size, but there are many
 * uses for in-state byte arrays (e.g. smart contract bytecode) which require
 * more than may fit within a single transaction. The `appendFile` transaction
 * exists to support these requirements. The typical pattern is to create a
 * file, append more data until the full content is stored, verify the file is
 * correct, then update the file entry with any final metadata changes (e.g.
 * adding threshold keys and removing the initial upload key).
 *
 * Each append transaction MUST remain within the total transaction size limit
 * for the network (typically 6144 bytes).<br/>
 * The total size of a file MUST remain within the maximum file size limit for
 * the network (typically 1048576 bytes).
 *
 * #### Signature Requirements
 * Append transactions MUST have signatures from _all_ keys in the `KeyList`
 * assigned to the `keys` field of the file.<br/>
 * See the [File Service](#FileService) specification for a detailed
 * explanation of the signature requirements for all file transactions.
 *
 * ### Block Stream Effects
 * None
 */
message FileAppendTransactionBody {
    /**
     * A file identifier.<br/>
     * This identifies the file to which the `contents` will be appended.
     * <p>
     * This field is REQUIRED.<br/>
     * The identified file MUST exist.<br/>
     * The identified file MUST NOT be larger than the current maximum file
     * size limit.<br/>
     * The identified file MUST NOT be deleted.<br/>
     * The identified file MUST NOT be immutable.
     */
    FileID fileID = 2;

    /**
     * An array of bytes to append.<br/>
     * <p>
     * This content SHALL be appended to the identified file if this
     * transaction succeeds.<br/>
     * This field is REQUIRED.<br/>
     * This field MUST NOT be empty.
     */
    bytes contents = 4;
}