foreign/node/src/wire/command.utils.ts

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
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import type { CommandResponse, ClientProvider } from '../client/client.type.js';

/**
 * Represents a command that can be sent to the Iggy server.
 *
 * @typeParam I - Input type for the command arguments
 * @typeParam O - Output type for the command response
 */
export type Command<I, O> = {
  /** Command code identifying the operation */
  code: number,
  /** Function to serialize command arguments to a Buffer */
  serialize: (args: I) => Buffer,
  /** Function to deserialize the server response */
  deserialize: (r: CommandResponse) => O
}


/**
 * Wraps a command definition into an executable function.
 * Creates a function that handles serialization, sending, and deserialization.
 *
 * @typeParam I - Input type for the command arguments
 * @typeParam O - Output type for the command response
 * @param cmd - Command definition with code, serialize, and deserialize functions
 * @returns A function that takes a ClientProvider and returns an async command executor
 */
export function wrapCommand<I, O>(cmd: Command<I, O>) {
  return (getClient: ClientProvider) =>
    async (arg: I) => {
      const payload = cmd.serialize(arg);
      const client = await getClient();
      return cmd.deserialize(await client.sendCommand(cmd.code, payload));
    };
};