Struct nx_request_handler::RequestEngine

pub struct RequestEngine { /* private fields */ }

An engine for streamlining the handling of backend requests by skyline-web applications.

Implementations

impl RequestEngine

pub fn new(session: WebSession) -> Self

Creates a new RequestEngine, taking ownership of the session in the process.

pub fn register<S: ToString>(
    &mut self,
    request_name: S,
    arg_count: Option<usize>,
    handler: impl Fn(&mut MessageContext<'_>) -> Result<String, String> + 'static
) -> &mut Self

Registers a handler for requests with the given name.

Arguments

• request_name - the name of the request to listen for
• arg_count - an optional number of arguments to expect. If None is supplied, this argument does nothing. If Some is supplied, then the engine will validate that the inbound request has the required arguments present before calling the registered handler. If the argument count is incorrect, the handler will not be called and an error will be returned to the frontend instead.
• handler - this is a closure or function, which takes a MessageContext and must return Result<String, String>. The returned value (Ok or Err) is then sent to the frontend as an accept() or reject() on the original Promise. Note that the returned string can be populated with JSON data. Such JSON can then be used in the frontend via JSON.parse() to retreive complex structures.

Example:

engine.register("my_call_name", Some(3), |context| {
    let args = context.arguments.unwrap();
    return Ok(format!("args: {}, {}, {}", args[0], args[1], args[2]));
})

pub fn register_defaults(&mut self) -> &mut Self

Registers the “default” handlers for some common functionality. This aligns with the nx-request-api NPM package’s DefaultMessenger. Default calls:

• ping
  • returns ok if the backend responded to the request
• read_file
  • returns the file’s contents as a string
• download_file
  • downloads the given file to the given location
• delete_file
  • deletes the given file
• write_file
  • writes the given string to the given file location
• get_md5
  • returns the md5 checksum of the given file
• unzip
  • unzips the given file as to the given location
• file_exists
  • returns whether the given path exists and is a file
• dir_exists
  • returns whether the given path exists and is a directory
• list_all_files
  • returns a tree structure of the given directory, recursively
• list_dir
  • returns a list of the files and directories in the given path (non recursive)
• get_request
  • performs a GET request (using smashnet) and returns the body as a string
• exit_session
  • signals the engine to shutdown and the session to close, unblocking start()
• exit_application
  • closes the application entirely (you will return to the home menu)

pub fn start(&mut self)

Start the request engine. This will block and internally loop until shutdown() has been called by a handler (such as with exitSession() in the DefaultMessenger, or via context.shutdown() in a registered custom handler);