routing 0.14.0

// Copyright 2015 MaidSafe.net limited.
//
// This SAFE Network Software is licensed to you under (1) the MaidSafe.net Commercial License,
// version 1.0 or later, or (2) The General Public License (GPL), version 3, depending on which
// licence you accepted on initial access to the Software (the "Licences").
//
// By contributing code to the SAFE Network Software, or to this project generally, you agree to be
// bound by the terms of the MaidSafe Contributor Agreement, version 1.0.  This, along with the
// Licenses can be found in the root directory of this project at LICENSE, COPYING and CONTRIBUTOR.
//
// Unless required by applicable law or agreed to in writing, the SAFE Network Software distributed
// under the GPL Licence is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.
//
// Please review the Licences for the specific language governing permissions and limitations
// relating to use of the SAFE Network Software.

#[cfg(not(feature = "use-mock-crust"))]
use maidsafe_utilities::thread::RaiiThreadJoiner;
use sodiumoxide;
#[cfg(feature = "use-mock-crust")]
use std::cell::RefCell;
use std::sync::mpsc::{Receiver, Sender, channel};

use action::Action;
use authority::Authority;
use core::Core;
use data::{Data, DataRequest};
use error::{InterfaceError, RoutingError};
use event::Event;
use messages::{RequestContent, RequestMessage, ResponseContent, ResponseMessage, RoutingMessage};
use xor_name::XorName;
use types::MessageId;

type RoutingResult = Result<(), RoutingError>;

/// Interface for sending and receiving messages to and from other nodes, in the role of a full
/// routing node.
///
/// A node is a part of the network that can route messages and be member of a group authority. Its
/// methods can be used to send requests and responses as either an individual `ManagedNode` or as
/// a part of a group authority. Their `src` argument indicates that role, so it must always either
/// be the `ManagedNode` with this node's name, or the `ClientManager` or `NodeManager` or
/// `NaeManager` with the address of a client, node or data element that this node is close to.
pub struct Node {
    interface_result_tx: Sender<Result<(), InterfaceError>>,
    interface_result_rx: Receiver<Result<(), InterfaceError>>,
    action_sender: ::types::RoutingActionSender,

    #[cfg(feature = "use-mock-crust")]
    core: RefCell<Core>,

    #[cfg(not(feature = "use-mock-crust"))]
    _raii_joiner: ::maidsafe_utilities::thread::RaiiThreadJoiner,
}

impl Node {
    /// Create a new `Node`.
    ///
    /// It will automatically connect to the network in the same way a client does, but then
    /// request a new name and integrate itself into the network using the new name.
    ///
    /// The intial `Node` object will have newly generated keys.
    #[cfg(not(feature = "use-mock-crust"))]
    pub fn new(event_sender: Sender<Event>, use_data_cache: bool) -> Result<Node, RoutingError> {
        sodiumoxide::init();  // enable shared global (i.e. safe to multithread now)

        // start the handler for routing without a restriction to become a full node
        let (action_sender, mut core) = Core::new(event_sender, false, None, use_data_cache);
        let (tx, rx) = channel();

        let raii_joiner = RaiiThreadJoiner::new(thread!("Node thread", move || {
            core.run();
        }));

        Ok(Node {
            interface_result_tx: tx,
            interface_result_rx: rx,
            action_sender: action_sender,
            _raii_joiner: raii_joiner,
        })
    }

    /// Create a new `Node` for unit testing.
    #[cfg(feature = "use-mock-crust")]
    pub fn new(event_sender: Sender<Event>, use_data_cache: bool) -> Result<Node, RoutingError> {
        sodiumoxide::init();  // enable shared global (i.e. safe to multithread now)

        // start the handler for routing without a restriction to become a full node
        let (action_sender, core) = Core::new(event_sender, false, None, use_data_cache);
        let (tx, rx) = channel();

        Ok(Node {
            interface_result_tx: tx,
            interface_result_rx: rx,
            action_sender: action_sender,
            core: RefCell::new(core),
        })
    }

    #[cfg(feature = "use-mock-crust")]
    #[allow(missing_docs)]
    pub fn poll(&self) -> bool {
        self.core.borrow_mut().poll()
    }

    /// Send a `Get` request to `dst` to retrieve data from the network.
    pub fn send_get_request(&self,
                            src: Authority,
                            dst: Authority,
                            data_request: DataRequest,
                            id: MessageId)
                            -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Request(RequestMessage {
            src: src,
            dst: dst,
            content: RequestContent::Get(data_request, id),
        });
        self.send_action(routing_msg)
    }

    /// Send a `Put` request to `dst` to store data on the network.
    pub fn send_put_request(&self,
                            src: Authority,
                            dst: Authority,
                            data: Data,
                            id: MessageId)
                            -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Request(RequestMessage {
            src: src,
            dst: dst,
            content: RequestContent::Put(data, id),
        });
        self.send_action(routing_msg)
    }

    /// Send a `Post` request to `dst` to modify data on the network.
    pub fn send_post_request(&self,
                             src: Authority,
                             dst: Authority,
                             data: Data,
                             id: MessageId)
                             -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Request(RequestMessage {
            src: src,
            dst: dst,
            content: RequestContent::Post(data, id),
        });
        self.send_action(routing_msg)
    }

    /// Send a `Delete` request to `dst` to remove data from the network.
    pub fn send_delete_request(&self,
                               src: Authority,
                               dst: Authority,
                               data: Data,
                               id: MessageId)
                               -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Request(RequestMessage {
            src: src,
            dst: dst,
            content: RequestContent::Delete(data, id),
        });
        self.send_action(routing_msg)
    }

    /// Respond to a `Get` request indicating success and sending the requested data.
    pub fn send_get_success(&self,
                            src: Authority,
                            dst: Authority,
                            data: Data,
                            id: MessageId)
                            -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Response(ResponseMessage {
            src: src,
            dst: dst,
            content: ResponseContent::GetSuccess(data, id),
        });
        self.send_action(routing_msg)
    }

    /// Respond to a `Get` request indicating failure.
    pub fn send_get_failure(&self,
                            src: Authority,
                            dst: Authority,
                            request: RequestMessage,
                            external_error_indicator: Vec<u8>,
                            id: MessageId)
                            -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Response(ResponseMessage {
            src: src,
            dst: dst,
            content: ResponseContent::GetFailure {
                id: id,
                request: request,
                external_error_indicator: external_error_indicator,
            },
        });
        self.send_action(routing_msg)
    }

    /// Respond to a `Put` request indicating success.
    pub fn send_put_success(&self,
                            src: Authority,
                            dst: Authority,
                            id: MessageId)
                            -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Response(ResponseMessage {
            src: src,
            dst: dst,
            content: ResponseContent::PutSuccess(id),
        });
        self.send_action(routing_msg)
    }

    /// Respond to a `Put` request indicating failure.
    pub fn send_put_failure(&self,
                            src: Authority,
                            dst: Authority,
                            request: RequestMessage,
                            external_error_indicator: Vec<u8>,
                            id: MessageId)
                            -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Response(ResponseMessage {
            src: src,
            dst: dst,
            content: ResponseContent::PutFailure {
                id: id,
                request: request,
                external_error_indicator: external_error_indicator,
            },
        });
        self.send_action(routing_msg)
    }

    /// Respond to a `Post` request indicating success.
    pub fn send_post_success(&self,
                             src: Authority,
                             dst: Authority,
                             id: MessageId)
                             -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Response(ResponseMessage {
            src: src,
            dst: dst,
            content: ResponseContent::PostSuccess(id),
        });
        self.send_action(routing_msg)
    }

    /// Respond to a `Post` request indicating failure.
    pub fn send_post_failure(&self,
                             src: Authority,
                             dst: Authority,
                             request: RequestMessage,
                             external_error_indicator: Vec<u8>,
                             id: MessageId)
                             -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Response(ResponseMessage {
            src: src,
            dst: dst,
            content: ResponseContent::PostFailure {
                id: id,
                request: request,
                external_error_indicator: external_error_indicator,
            },
        });
        self.send_action(routing_msg)
    }

    /// Respond to a `Delete` request indicating success.
    pub fn send_delete_success(&self,
                               src: Authority,
                               dst: Authority,
                               id: MessageId)
                               -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Response(ResponseMessage {
            src: src,
            dst: dst,
            content: ResponseContent::DeleteSuccess(id),
        });
        self.send_action(routing_msg)
    }

    /// Respond to a `Delete` request indicating failure.
    pub fn send_delete_failure(&self,
                               src: Authority,
                               dst: Authority,
                               request: RequestMessage,
                               external_error_indicator: Vec<u8>,
                               id: MessageId)
                               -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Response(ResponseMessage {
            src: src,
            dst: dst,
            content: ResponseContent::DeleteFailure {
                id: id,
                request: request,
                external_error_indicator: external_error_indicator,
            },
        });
        self.send_action(routing_msg)
    }

    /// Send a `Refresh` request from `src` to `src` to trigger churn.
    ///
    /// This is intended to be sent from a group authority (`src`) to itself whenever a node joins
    /// or leaves the group. If the quorum is reached, i. e. enough members agree that a change has
    /// happened, the churn mechanism is triggered to adapt to the change.
    pub fn send_refresh_request(&self,
                                src: Authority,
                                dst: Authority,
                                content: Vec<u8>,
                                id: MessageId)
                                -> Result<(), InterfaceError> {
        let routing_msg = RoutingMessage::Request(RequestMessage {
            src: src,
            dst: dst,
            content: RequestContent::Refresh(content, id),
        });
        self.send_action(routing_msg)
    }

    /// Returns the names of the nodes in the routing table which are closest to the given one.
    pub fn close_group(&self, name: XorName) -> Result<Option<Vec<XorName>>, InterfaceError> {
        let (result_tx, result_rx) = channel();
        try!(self.action_sender.send(Action::CloseGroup {
            name: name,
            result_tx: result_tx,
        }));

        self.receive_action_result(&result_rx)
    }

    /// Returns the name of this node.
    pub fn name(&self) -> Result<XorName, InterfaceError> {
        let (result_tx, result_rx) = channel();
        try!(self.action_sender.send(Action::Name { result_tx: result_tx }));

        self.receive_action_result(&result_rx)
    }

    /// Returns the name of this node.
    pub fn quorum_size(&self) -> Result<usize, InterfaceError> {
        let (result_tx, result_rx) = channel();
        try!(self.action_sender.send(Action::QuorumSize { result_tx: result_tx }));

        self.receive_action_result(&result_rx)
    }

    fn send_action(&self, routing_msg: RoutingMessage) -> Result<(), InterfaceError> {
        try!(self.action_sender.send(Action::NodeSendMessage {
            content: routing_msg,
            result_tx: self.interface_result_tx.clone(),
        }));

        try!(self.receive_action_result(&self.interface_result_rx))
    }

    #[cfg(not(feature = "use-mock-crust"))]
    fn receive_action_result<T>(&self, rx: &Receiver<T>) -> Result<T, InterfaceError> {
        Ok(try!(rx.recv()))
    }

    #[cfg(feature = "use-mock-crust")]
    fn receive_action_result<T>(&self, rx: &Receiver<T>) -> Result<T, InterfaceError> {
        while self.poll() {}
        Ok(try!(rx.recv()))
    }
}

impl Drop for Node {
    fn drop(&mut self) {
        if let Err(err) = self.action_sender.send(Action::Terminate) {
            error!("Error {:?} sending event Core", err);
        }
    }
}

// #[cfg(test)]
// mod test {

// pub struct RoutingNetwork;

// impl RoutingNetwork {

//         fn new(size: u32) -> RoutingNetwork {
//             ::utils::initialise_logger(true);


//             let node = || { let _ =
//                 ::std::thread::spawn(move || ::test_utils::node::Node::new().run());
//             };
//             for i in 0..size { node(); ::std::thread::sleep_ms(1000 + i * 1000); }
//             ::std::thread::sleep_ms(size * 1000);

//             RoutingNetwork
//         }
//     }

//     fn calculate_key_name(key: &::std::string::String) -> XorName {
//         XorName::new(::sodiumoxide::crypto::hash::sha512::hash(key.as_bytes()).0)
//     }

//     #[test]
//     fn unit_client_put_get() {
//         // let _ = RoutingNetwork::new(10u32);
//         debug!("Starting client");
//         let mut client = ::test_utils::client::Client::new();
//         ::std::thread::sleep_ms(2000);

//         let key = ::std::string::String::from("key");
//         let value = ::std::string::String::from("value");
//         let name = calculate_key_name(&key.clone());
//         let data = unwrap_result!(::utils::encode(&(key, value)));
//         let data = ::data::Data::PlainData(::plain_data::PlainData::new(name.clone(), data));

//         debug!("Putting data {:?}", data);
//         client.put(data.clone());
//         ::std::thread::sleep_ms(5000);

//         let recovered_data = match client.get(::data::DataRequest::PlainData(name)) {
//             Some(data) => data,
//             None => panic!("Failed to recover stored data: {}.", name),
//         };

//         debug!("Recovered data {:?}", recovered_data);
//         assert_eq!(recovered_data, data);
//     }
// }