diff options
Diffstat (limited to 'src/lightstreamer_client.rs')
| -rw-r--r-- | src/lightstreamer_client.rs | 458 |
1 files changed, 458 insertions, 0 deletions
diff --git a/src/lightstreamer_client.rs b/src/lightstreamer_client.rs new file mode 100644 index 0000000..2012c28 --- /dev/null +++ b/src/lightstreamer_client.rs @@ -0,0 +1,458 @@ +use crate::client_listener::ClientListener; +use crate::client_message_listener::ClientMessageListener; +use crate::connection_details::ConnectionDetails; +use crate::connection_options::ConnectionOptions; +use crate::subscription::Subscription; +use crate::IllegalStateException; + +use cookie::Cookie; + +/// Facade class for the management of the communication to Lightstreamer Server. Used to provide +/// configuration settings, event handlers, operations for the control of the connection lifecycle, +/// Subscription handling and to send messages. +/// +/// An instance of `LightstreamerClient` handles the communication with Lightstreamer Server on a +/// specified endpoint. Hence, it hosts one "Session"; or, more precisely, a sequence of Sessions, +/// since any Session may fail and be recovered, or it can be interrupted on purpose. So, normally, +/// a single instance of `LightstreamerClient` is needed. +/// +/// However, multiple instances of `LightstreamerClient` can be used, toward the same or multiple +/// endpoints. +/// +/// You can listen to the events generated by a session by registering an event listener, such as +/// `ClientListener` or `SubscriptionListener`. These listeners allow you to handle various events, +/// such as session creation, connection status, subscription updates, and server messages. However, +/// you should be aware that the event notifications are dispatched by a single thread, the so-called +/// event thread. This means that if the operations of a listener are slow or blocking, they will +/// delay the processing of the other listeners and affect the performance of your application. +/// Therefore, you should delegate any slow or blocking operations to a dedicated thread, and keep +/// the listener methods as fast and simple as possible. Note that even if you create multiple +/// instances of `LightstreamerClient`, they will all use a single event thread, that is shared +/// among them. +/// +/// # Parameters +/// +/// * `server_address`: the address of the Lightstreamer Server to which this `LightstreamerClient` +/// will connect to. It is possible to specify it later by using `None` here. See +/// `ConnectionDetails.setServerAddress()` for details. +/// * `adapter_set`: the name of the Adapter Set mounted on Lightstreamer Server to be used to handle +/// all requests in the Session associated with this `LightstreamerClient`. It is possible not to +/// specify it at all or to specify it later by using `None` here. See `ConnectionDetails.setAdapterSet()` +/// for details. +/// +/// # Raises +/// +/// * `IllegalArgumentException`: if a not valid address is passed. See `ConnectionDetails.setServerAddress()` +/// for details. +pub struct LightstreamerClient { + server_address: Option<String>, + adapter_set: Option<String>, + /// Data object that contains the details needed to open a connection to a Lightstreamer Server. + /// This instance is set up by the `LightstreamerClient` object at its own creation. Properties + /// of this object can be overwritten by values received from a Lightstreamer Server. + pub connection_details: ConnectionDetails, + /// Data object that contains options and policies for the connection to the server. This instance + /// is set up by the `LightstreamerClient` object at its own creation. Properties of this object + /// can be overwritten by values received from a Lightstreamer Server. + pub connection_options: ConnectionOptions, + listeners: Vec<Box<dyn ClientListener>>, + subscriptions: Vec<Subscription>, +} + +impl LightstreamerClient { + /// A constant string representing the name of the library. + pub const LIB_NAME: &'static str = "rust_client"; + + /// A constant string representing the version of the library. + pub const LIB_VERSION: &'static str = "0.1.0"; + + /// Static method that can be used to share cookies between connections to the Server (performed by + /// this library) and connections to other sites that are performed by the application. With this + /// method, cookies received by the application can be added (or replaced if already present) to + /// the cookie set used by the library to access the Server. Obviously, only cookies whose domain + /// is compatible with the Server domain will be used internally. + /// + /// This method should be invoked before calling the `LightstreamerClient.connect()` method. + /// However it can be invoked at any time; it will affect the internal cookie set immediately + /// and the sending of cookies on the next HTTP request or WebSocket establishment. + /// + /// # Parameters + /// + /// * `uri`: the URI from which the supplied cookies were received. It cannot be `None`. + /// * `cookies`: an instance of `http.cookies.SimpleCookie`. + /// + /// See also `getCookies()` + pub fn add_cookies(uri: &str, cookies: &Cookie) { + // Implementation for add_cookies + } + + /// Adds a listener that will receive events from the `LightstreamerClient` instance. + /// + /// The same listener can be added to several different `LightstreamerClient` instances. + /// + /// A listener can be added at any time. A call to add a listener already present will be ignored. + /// + /// # Parameters + /// + /// * `listener`: An object that will receive the events as documented in the `ClientListener` + /// interface. + /// + /// See also `removeListener()` + pub fn add_listener(&mut self, listener: Box<dyn ClientListener>) { + self.listeners.push(listener); + } + + /// Operation method that requests to open a Session against the configured Lightstreamer Server. + /// + /// When `connect()` is called, unless a single transport was forced through `ConnectionOptions.setForcedTransport()`, + /// the so called "Stream-Sense" mechanism is started: if the client does not receive any answer + /// for some seconds from the streaming connection, then it will automatically open a polling + /// connection. + /// + /// A polling connection may also be opened if the environment is not suitable for a streaming + /// connection. + /// + /// Note that as "polling connection" we mean a loop of polling requests, each of which requires + /// opening a synchronous (i.e. not streaming) connection to Lightstreamer Server. + /// + /// Note that the request to connect is accomplished by the client in a separate thread; this + /// means that an invocation to `getStatus()` right after `connect()` might not reflect the change + /// yet. + /// + /// When the request to connect is finally being executed, if the current status of the client + /// is not `DISCONNECTED`, then nothing will be done. + /// + /// # Raises + /// + /// * `IllegalStateException`: if no server address was configured. + /// + /// See also `getStatus()` + /// + /// See also `disconnect()` + /// + /// See also `ClientListener.onStatusChange()` + /// + /// See also `ConnectionDetails.setServerAddress()` + pub fn connect(&mut self) -> Result<(), IllegalStateException> { + if self.server_address.is_none() { + return Err(IllegalStateException::new("No server address was configured.")); + } + + // Implementation for connect + Ok(()) + } + + /// Operation method that requests to close the Session opened against the configured Lightstreamer + /// Server (if any). + /// + /// When `disconnect()` is called, the "Stream-Sense" mechanism is stopped. + /// + /// Note that active `Subscription` instances, associated with this `LightstreamerClient` instance, + /// are preserved to be re-subscribed to on future Sessions. + /// + /// Note that the request to disconnect is accomplished by the client in a separate thread; this + /// means that an invocation to `getStatus()` right after `disconnect()` might not reflect the + /// change yet. + /// + /// When the request to disconnect is finally being executed, if the status of the client is + /// "DISCONNECTED", then nothing will be done. + /// + /// See also `connect()` + pub fn disconnect(&mut self) { + // Implementation for disconnect + } + + /// Static inquiry method that can be used to share cookies between connections to the Server + /// (performed by this library) and connections to other sites that are performed by the application. + /// With this method, cookies received from the Server can be extracted for sending through other + /// connections, according with the URI to be accessed. + /// + /// See `addCookies()` for clarifications on when cookies are directly stored by the library and + /// when not. + /// + /// # Parameters + /// + /// * `uri`: the URI to which the cookies should be sent, or `None`. + /// + /// # Returns + /// + /// A list with the various cookies that can be sent in a HTTP request for the specified URI. + /// If a `None` URI was supplied, all available non-expired cookies will be returned. + pub fn get_cookies(uri: Option<&str>) -> Cookie { + // Implementation for get_cookies + unimplemented!() + } + + /// Returns a list containing the `ClientListener` instances that were added to this client. + /// + /// # Returns + /// + /// A list containing the listeners that were added to this client. + /// + /// See also `addListener()` + pub fn get_listeners(&self) -> &Vec<Box<dyn ClientListener>> { + &self.listeners + } + + /// Inquiry method that gets the current client status and transport (when applicable). + /// + /// # Returns + /// + /// The current client status. It can be one of the following values: + /// + /// - `"CONNECTING"`: the client is waiting for a Server's response in order to establish a connection; + /// - `"CONNECTED:STREAM-SENSING"`: the client has received a preliminary response from the server + /// and is currently verifying if a streaming connection is possible; + /// - `"CONNECTED:WS-STREAMING"`: a streaming connection over WebSocket is active; + /// - `"CONNECTED:HTTP-STREAMING"`: a streaming connection over HTTP is active; + /// - `"CONNECTED:WS-POLLING"`: a polling connection over WebSocket is in progress; + /// - `"CONNECTED:HTTP-POLLING"`: a polling connection over HTTP is in progress; + /// - `"STALLED"`: the Server has not been sending data on an active streaming connection for + /// longer than a configured time; + /// - `"DISCONNECTED:WILL-RETRY"`: no connection is currently active but one will be opened + /// (possibly after a timeout); + /// - `"DISCONNECTED:TRYING-RECOVERY"`: no connection is currently active, but one will be opened + /// as soon as possible, as an attempt to recover the current session after a connection issue; + /// - `"DISCONNECTED"`: no connection is currently active. + /// + /// See also `ClientListener.onStatusChange()` + pub fn get_status(&self) -> &str { + // Implementation for get_status + unimplemented!() + } + + /// Inquiry method that returns a list containing all the `Subscription` instances that are + /// currently "active" on this `LightstreamerClient`. + /// + /// Internal second-level `Subscription` are not included. + /// + /// # Returns + /// + /// A list, containing all the `Subscription` currently "active" on this `LightstreamerClient`. + /// The list can be empty. + /// + /// See also `subscribe()` + pub fn get_subscriptions(&self) -> &Vec<Subscription> { + &self.subscriptions + } + + /// Removes a listener from the `LightstreamerClient` instance so that it will not receive + /// events anymore. + /// + /// A listener can be removed at any time. + /// + /// # Parameters + /// + /// * `listener`: The listener to be removed. + /// + /// See also `addListener()` + pub fn remove_listener(&mut self, listener: Box<dyn ClientListener>) { + unimplemented!("Implement mechanism to remove listener from LightstreamerClient"); + //self.listeners.remove(&listener); + } + + /// Operation method that sends a message to the Server. The message is interpreted and handled + /// by the Metadata Adapter associated to the current Session. This operation supports in-order + /// guaranteed message delivery with automatic batching. In other words, messages are guaranteed + /// to arrive exactly once and respecting the original order, whatever is the underlying transport + /// (HTTP or WebSockets). Furthermore, high frequency messages are automatically batched, if + /// necessary, to reduce network round trips. + /// + /// Upon subsequent calls to the method, the sequential management of the involved messages is + /// guaranteed. The ordering is determined by the order in which the calls to `sendMessage` are + /// issued. + /// + /// If a message, for any reason, doesn't reach the Server (this is possible with the HTTP transport), + /// it will be resent; however, this may cause the subsequent messages to be delayed. For this + /// reason, each message can specify a "delayTimeout", which is the longest time the message, + /// after reaching the Server, can be kept waiting if one of more preceding messages haven't + /// been received yet. If the "delayTimeout" expires, these preceding messages will be discarded; + /// any discarded message will be notified to the listener through `ClientMessageListener.onDiscarded()`. + /// Note that, because of the parallel transport of the messages, if a zero or very low timeout + /// is set for a message and the previous message was sent immediately before, it is possible + /// that the latter gets discarded even if no communication issues occur. The Server may also + /// enforce its own timeout on missing messages, to prevent keeping the subsequent messages for + /// long time. + /// + /// Sequence identifiers can also be associated with the messages. In this case, the sequential + /// management is restricted to all subsets of messages with the same sequence identifier associated. + /// + /// Notifications of the operation outcome can be received by supplying a suitable listener. The + /// supplied listener is guaranteed to be eventually invoked; listeners associated with a sequence + /// are guaranteed to be invoked sequentially. + /// + /// The "UNORDERED_MESSAGES" sequence name has a special meaning. For such a sequence, immediate + /// processing is guaranteed, while strict ordering and even sequentialization of the processing + /// is not enforced. Likewise, strict ordering of the notifications is not enforced. However, + /// messages that, for any reason, should fail to reach the Server whereas subsequent messages + /// had succeeded, might still be discarded after a server-side timeout, in order to ensure that + /// the listener eventually gets a notification. + /// + /// Moreover, if "UNORDERED_MESSAGES" is used and no listener is supplied, a "fire and forget" + /// scenario is assumed. In this case, no checks on missing, duplicated or overtaken messages + /// are performed at all, so as to optimize the processing and allow the highest possible throughput. + /// + /// Since a message is handled by the Metadata Adapter associated to the current connection, a + /// message can be sent only if a connection is currently active. If the special `enqueueWhileDisconnected` + /// flag is specified it is possible to call the method at any time and the client will take + /// care of sending the message as soon as a connection is available, otherwise, if the current + /// status is "DISCONNECTED*", the message will be abandoned and the `ClientMessageListener.onAbort()` + /// event will be fired. + /// + /// Note that, in any case, as soon as the status switches again to "DISCONNECTED*", any message + /// still pending is aborted, including messages that were queued with the `enqueueWhileDisconnected` + /// flag set to `true`. + /// + /// Also note that forwarding of the message to the server is made in a separate thread, hence, + /// if a message is sent while the connection is active, it could be aborted because of a subsequent + /// disconnection. In the same way a message sent while the connection is not active might be + /// sent because of a subsequent connection. + /// + /// # Parameters + /// + /// * `message`: a text message, whose interpretation is entirely demanded to the Metadata Adapter + /// associated to the current connection. + /// * `sequence`: an alphanumeric identifier, used to identify a subset of messages to be managed + /// in sequence; underscore characters are also allowed. If the "UNORDERED_MESSAGES" identifier + /// is supplied, the message will be processed in the special way described above. The parameter + /// is optional; if set to `None`, "UNORDERED_MESSAGES" is used as the sequence name. + /// * `delay_timeout`: a timeout, expressed in milliseconds. If higher than the Server configured + /// timeout on missing messages, the latter will be used instead. The parameter is optional; if + /// a negative value is supplied, the Server configured timeout on missing messages will be applied. + /// This timeout is ignored for the special "UNORDERED_MESSAGES" sequence, although a server-side + /// timeout on missing messages still applies. + /// * `listener`: an object suitable for receiving notifications about the processing outcome. The + /// parameter is optional; if not supplied, no notification will be available. + /// * `enqueue_while_disconnected`: if this flag is set to `true`, and the client is in a disconnected + /// status when the provided message is handled, then the message is not aborted right away but + /// is queued waiting for a new session. Note that the message can still be aborted later when + /// a new session is established. + pub fn send_message( + &mut self, + message: &str, + sequence: Option<&str>, + delay_timeout: Option<u64>, + listener: Option<Box<dyn ClientMessageListener>>, + enqueue_while_disconnected: bool, + ) { + // Implementation for send_message + } + + /// Static method that permits to configure the logging system used by the library. The logging + /// system must respect the `LoggerProvider` interface. A custom class can be used to wrap any + /// third-party logging system. + /// + /// If no logging system is specified, all the generated log is discarded. + /// + /// The following categories are available to be consumed: + /// + /// - `lightstreamer.stream`: logs socket activity on Lightstreamer Server connections; at INFO + /// level, socket operations are logged; at DEBUG level, read/write data exchange is logged. + /// - `lightstreamer.protocol`: logs requests to Lightstreamer Server and Server answers; at INFO + /// level, requests are logged; at DEBUG level, request details and events from the Server are logged. + /// - `lightstreamer.session`: logs Server Session lifecycle events; at INFO level, lifecycle events + /// are logged; at DEBUG level, lifecycle event details are logged. + /// - `lightstreamer.subscriptions`: logs subscription requests received by the clients and the related + /// updates; at WARN level, alert events from the Server are logged; at INFO level, subscriptions + /// and unsubscriptions are logged; at DEBUG level, requests batching and update details are logged. + /// - `lightstreamer.actions`: logs settings / API calls. + /// + /// # Parameters + /// + /// * `provider`: A `LoggerProvider` instance that will be used to generate log messages by the + /// library classes. + pub fn set_logger_provider() { + unimplemented!("Implement mechanism to set logger provider for LightstreamerClient."); + } + /* + pub fn set_logger_provider(provider: LoggerProvider) { + // Implementation for set_logger_provider + } + */ + + /// Provides a mean to control the way TLS certificates are evaluated, with the possibility to + /// accept untrusted ones. + /// + /// May be called only once before creating any `LightstreamerClient` instance. + /// + /// # Parameters + /// + /// * `factory`: an instance of `ssl.SSLContext` + /// + /// # Raises + /// + /// * `IllegalArgumentException`: if the factory is `None` + /// * `IllegalStateException`: if a factory is already installed + pub fn set_trust_manager_factory() { + unimplemented!("Implement mechanism to set trust manager factory for LightstreamerClient."); + } + /* + pub fn set_trust_manager_factory(factory: Option<SslContext>) -> Result<(), IllegalArgumentException> { + if factory.is_none() { + return Err(IllegalArgumentException::new( + "Factory cannot be None", + )); + } + + // Implementation for set_trust_manager_factory + Ok(()) + } + */ + + /// Operation method that adds a `Subscription` to the list of "active" Subscriptions. The `Subscription` + /// cannot already be in the "active" state. + /// + /// Active subscriptions are subscribed to through the server as soon as possible (i.e. as soon + /// as there is a session available). Active `Subscription` are automatically persisted across different + /// sessions as long as a related unsubscribe call is not issued. + /// + /// Subscriptions can be given to the `LightstreamerClient` at any time. Once done the `Subscription` + /// immediately enters the "active" state. + /// + /// Once "active", a `Subscription` instance cannot be provided again to a `LightstreamerClient` + /// unless it is first removed from the "active" state through a call to `unsubscribe()`. + /// + /// Also note that forwarding of the subscription to the server is made in a separate thread. + /// + /// A successful subscription to the server will be notified through a `SubscriptionListener.onSubscription()` + /// event. + /// + /// # Parameters + /// + /// * `subscription`: A `Subscription` object, carrying all the information needed to process real-time + /// values. + /// + /// See also `unsubscribe()` + pub fn subscribe(&mut self, subscription: Subscription) { + self.subscriptions.push(subscription); + // Implementation for subscribe + } + + /// Operation method that removes a `Subscription` that is currently in the "active" state. + /// + /// By bringing back a `Subscription` to the "inactive" state, the unsubscription from all its + /// items is requested to Lightstreamer Server. + /// + /// Subscription can be unsubscribed from at any time. Once done the `Subscription` immediately + /// exits the "active" state. + /// + /// Note that forwarding of the unsubscription to the server is made in a separate thread. + /// + /// The unsubscription will be notified through a `SubscriptionListener.onUnsubscription()` event. + /// + /// # Parameters + /// + /// * `subscription`: An "active" `Subscription` object that was activated by this `LightstreamerClient` + /// instance. + pub fn unsubscribe(&mut self, subscription: Subscription) { + unimplemented!("Implement mechanism to unsubscribe from LightstreamerClient."); + } + /* + pub fn unsubscribe(&mut self, subscription: &Subscription) { + if let Some(index) = self.subscriptions.iter().position(|s| s == subscription) { + self.subscriptions.remove(index); + // Implementation for unsubscribe + } + } + */ +}
\ No newline at end of file |