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/// Configuration struct for WebSocket client (native Tungstenite connections only)
/// This `WebSocketConfig` is mirrored from Tungstenite, and has no effect when
/// used in the WASM (browser) environment due to lack of control in browser
/// websockets.
#[derive(Clone, Debug)]
pub struct WebSocketConfig {
    /// The target minimum size of the write buffer to reach before writing the data
    /// to the underlying stream.
    /// The default value is 128 KiB.
    ///
    /// If set to `0` each message will be eagerly written to the underlying stream.
    /// It is often more optimal to allow them to buffer a little, hence the default value.
    ///
    /// Note: [`flush`](WebSocket::flush) will always fully write the buffer regardless.
    pub write_buffer_size: usize,
    /// The max size of the write buffer in bytes. Setting this can provide backpressure
    /// in the case the write buffer is filling up due to write errors.
    /// The default value is unlimited.
    ///
    /// Note: The write buffer only builds up past [`write_buffer_size`](Self::write_buffer_size)
    /// when writes to the underlying stream are failing. So the **write buffer can not
    /// fill up if you are not observing write errors even if not flushing**.
    ///
    /// Note: Should always be at least [`write_buffer_size + 1 message`](Self::write_buffer_size)
    /// and probably a little more depending on error handling strategy.
    pub max_write_buffer_size: usize,
    /// The maximum size of a message. `None` means no size limit. The default value is 64 MiB
    /// which should be reasonably big for all normal use-cases but small enough to prevent
    /// memory eating by a malicious user.
    pub max_message_size: Option<usize>,
    /// The maximum size of a single message frame. `None` means no size limit. The limit is for
    /// frame payload NOT including the frame header. The default value is 16 MiB which should
    /// be reasonably big for all normal use-cases but small enough to prevent memory eating
    /// by a malicious user.
    pub max_frame_size: Option<usize>,
    /// When set to `true`, the server will accept and handle unmasked frames
    /// from the client. According to the RFC 6455, the server must close the
    /// connection to the client in such cases, however it seems like there are
    /// some popular libraries that are sending unmasked frames, ignoring the RFC.
    /// By default this option is set to `false`, i.e. according to RFC 6455.
    pub accept_unmasked_frames: bool,
}

impl Default for WebSocketConfig {
    fn default() -> Self {
        WebSocketConfig {
            write_buffer_size: 128 * 1024,
            max_write_buffer_size: usize::MAX,
            max_message_size: Some(64 << 20),
            max_frame_size: Some(16 << 20),
            accept_unmasked_frames: false,
        }
    }
}