Gestió de contacte

Aquesta secció presentarà com trobar i afegir un contacte del DHT al client. L’ús d’un servidor de noms no s’explicarà aquí. Si vols més detalls sobre això, llegeix Nombre Protocol del servidor.

Presència en la xarxa

Anunciar la presència en el DHT

La presència és bastant senzilla per anunciar en el DHT. De fet, és només un valor que conté el hash del dispositiu (véder la secció anterior, Gestió de comptes) en el hash corresponent a l’imprenta digital de la clau. Així, si tenim el compte bf5f1e21d3eb2c1246946aa49d5dcf3e5b9cb1b9 amb el dispositiu 62fbdff0ce86f368c7d3c2682539e5ba9e06404f, el següent valor definit serà enviat a través del DHT:

/**
 * Device announcement stored on DHT.
 */
struct DeviceAnnouncement : public dht::SignedValue<DeviceAnnouncement>
{
private:
    using BaseClass = dht::SignedValue<DeviceAnnouncement>;

public:
    static const constexpr dht::ValueType& TYPE = dht::ValueType::USER_DATA;
    dht::InfoHash dev;
    std::shared_ptr<dht::crypto::PublicKey> pk;
    MSGPACK_DEFINE_MAP(dev, pk)
};

(aquest valor es pot posar amb dht_.put(h, VALUE, dht::DoneCallback{}, {}, true);, com a un put permanent). Si el dispositiu és anunciat, el dispositiu està present. Per ara, no hi ha manera de eliminar o editar un valor en el DHT (això arribarà quan OpenDHT suportarà ECC). Així, la presència sempre té un retard per ara (d’acord: expiració/2, així que 2min30 per ara).

Contacta si hi ha contacte

Now our presence on the network, it’s time to get if somebody is present on the DHT. With the previous section, it’s easy to do the reverse process. To know if somebody is present on the DHT (ex: bf5f1e21d3eb2c1246946aa49d5dcf3e5b9cb1b9), we have to get value at bf5f1e21d3eb2c1246946aa49d5dcf3e5b9cb1b9 and retrieve the DeviceAnnouncement on this hash. The related code in the daemon is in jamiaccount.cpp:

auto shared = std::static_pointer_cast<RingAccount>(shared_from_this());
auto treatedDevices = std::make_shared<std::set<dht::InfoHash>>();
dht_.get<dht::crypto::RevocationList>(to, [to](dht::crypto::RevocationList&& crl){
    tls::CertificateStore::instance().pinRevocationList(to.toString(), std::move(crl));
    return true;
});
dht_.get<DeviceAnnouncement>(to, [shared,to,treatedDevices,op](DeviceAnnouncement&& dev) {
    if (dev.from != to)
        return true;
    if (treatedDevices->emplace(dev.dev).second)
        op(shared, dev.dev);
    return true;
}, [=](bool /*ok*/){
    {
        std::lock_guard<std::recursive_mutex> lock(shared->buddyInfoMtx);
        auto buddy_info_it = shared->trackedBuddies_.find(to);
        if (buddy_info_it != shared->trackedBuddies_.end()) {
            if (not treatedDevices->empty()) {
                for (auto& device_id : *treatedDevices)
                    shared->onTrackedBuddyOnline(buddy_info_it, device_id);
            } else
                shared->onTrackedBuddyOffline(buddy_info_it);
        }
    }
    RING_DBG("[Account %s] found %lu devices for %s",
                getAccountID().c_str(), treatedDevices->size(), to.to_c_str());
    if (end) end(shared, not treatedDevices->empty());
});

I això és tot.

Client perspective

<method name="subscribeBuddy" tp:name-for-bindings="subscribeBuddy">
    <tp:docstring>
        Ask be be notified when 'uri' presence change
    </tp:docstring>
    <tp:added version="1.3.0"/>
    <arg type="s" name="accountID" direction="in">
        <tp:docstring>
            An account from which get request presence informations
        </tp:docstring>
    </arg>
    <arg type="s" name="uri" direction="in">
        <tp:docstring>
            A SIP uri to watch
        </tp:docstring>
    </arg>
    <arg type="b" name="flag" direction="in">
        <tp:docstring>
        </tp:docstring>
    </arg>
</method>

<signal name="newBuddyNotification" tp:name-for-bindings="newBuddyNotification">
    <tp:added version="1.3.0"/>
    <tp:docstring>
        Notify when a registered presence uri presence informations changes
    </tp:docstring>
    <arg type="s" name="accountID">
        <tp:docstring>
            The associated account
        </tp:docstring>
    </arg>
    <arg type="s" name="buddyUri">
        <tp:docstring>
            The registered URI
        </tp:docstring>
    </arg>
    <arg type="i" name="status">
        <tp:docstring>
            Is the URI present or not
        </tp:docstring>
    </arg>
    <arg type="s" name="lineStatus">
        <tp:docstring>
            A string containing informations from the user (human readable)
        </tp:docstring>
    </arg>
</signal>

<method name="publish" tp:name-for-bindings="publish">
    <tp:added version="1.3.0"/>
    <arg type="s" name="accountID" direction="in">
        <tp:docstring>
            The account from which the presence will be emitted
        </tp:docstring>
    </arg>
    <arg type="b" name="status" direction="in">
        <tp:docstring>
            Is this account present or not
        </tp:docstring>
    </arg>
    <arg type="s" name="note" direction="in">
        <tp:docstring>
            A message transmitted by the server to other users
        </tp:docstring>
    </arg>
</method>

Are the main APIs for clients. subscribeBuddy will listen on the DHT to detect presence changes and newBuddyNotification will be sent whenever a new status is detected:

• The status sent to the client is now 0=offline (no device found on the DHT), 1=dht_presence (at least a device is found on the DHT), 2=connected (with a TCP + SIP channel, so ready to exchange data).

• lineStatus will contain any custom status sent by the peer (e.g. Lunch Time!)

publish is used for publishing a custom note (status is ignored for Jami accounts, note will contain the custom status).

RFC3863 is used to send status over the SIP connection.

Solicitud pendiente

Enviar una petició

Request d’embarcadors de TODO

Finalment, una vegada que s’ha elaborat la petició de confiança, podem empujar la petició al següent hash: InfoHash("inbox:" + deviceId)

El següent codi s’utilitza en el daemon:

dht_.putEncrypted(dht::InfoHash::get("inbox:"+dev.toString()), dev, dht::TrustRequest(DHT_TYPE_NS, payload));

Recepció d’una petició

Todo

(Acceptar/blocar/descarcarar)

API de Daemon

Tots els mètodes per seguir la presència d’un amic es troben en el PresenceManager com:

<signal name="newBuddyNotification" tp:name-for-bindings="newBuddyNotification">
    <tp:added version="1.3.0"/>
    <tp:docstring>
        Notify when a registered presence uri presence informations changes
    </tp:docstring>
    <arg type="s" name="accountID">
        <tp:docstring>
            The associated account
        </tp:docstring>
    </arg>
    <arg type="s" name="buddyUri">
        <tp:docstring>
            The registered URI
        </tp:docstring>
    </arg>
    <arg type="b" name="status">
        <tp:docstring>
            Is the URI present or not
        </tp:docstring>
    </arg>
    <arg type="s" name="lineStatus">
        <tp:docstring>
            A string containing informations from the user (human readable)
        </tp:docstring>
    </arg>
</signal>

Tots els mètodes i senyals utilitzats per gestionar les peticions de confiança i els contactes es troben en el ConfigurationManager com:

<method name="getTrustRequests" tp:name-for-bindings="getTrustRequests">
    <tp:added version="2.2.0"/>
    <arg type="s" name="accountID" direction="in">
    </arg>
    <annotation name="org.qtproject.QtDBus.QtTypeName.Out0" value="VectorMapStringString"/>
    <arg type="aa{ss}" name="requests" direction="out" >
        <tp:docstring>
            A list of contact request details. Details:
            - from: account ID of sender
            - received: UNIX timestamp of reception date
            - payload: attached payload
        </tp:docstring>
    </arg>
</method>

<method name="acceptTrustRequest" tp:name-for-bindings="acceptTrustRequest">
    <tp:added version="2.2.0"/>
    <arg type="s" name="accountID" direction="in">
    </arg>
    <arg type="s" name="from" direction="in">
    </arg>
    <arg type="b" name="success" direction="out" tp:type="Boolean">
        <tp:docstring>
            True if the operation succeeded.
        </tp:docstring>
    </arg>
</method>

<method name="discardTrustRequest" tp:name-for-bindings="discardTrustRequest">
    <tp:added version="2.2.0"/>
    <arg type="s" name="accountID" direction="in">
    </arg>
    <arg type="s" name="from" direction="in">
    </arg>
    <arg type="b" name="success" direction="out" tp:type="Boolean">
        <tp:docstring>
            True if the operation succeeded.
        </tp:docstring>
    </arg>
</method>

<signal name="incomingTrustRequest" tp:name-for-bindings="incomingTrustRequest">
    <tp:added version="2.2.0"/>
    <tp:docstring>
        Notify clients that a new contact request has been received.
    </tp:docstring>
    <arg type="s" name="accountID">
    </arg>
    <arg type="s" name="from">
    </arg>
    <arg type="ay" name="payload">
    </arg>
    <arg type="t" name="receiveTime">
    </arg>
</signal>

<method name="sendTrustRequest" tp:name-for-bindings="sendTrustRequest">
    <tp:added version="2.2.0"/>
    <arg type="s" name="accountID" direction="in">
    </arg>
    <arg type="s" name="to" direction="in">
    </arg>
    <arg type="ay" name="payload" direction="in">
    </arg>
</method>

<method name="addContact" tp:name-for-bindings="addContact">
    <tp:added version="3.0.0"/>
    <arg type="s" name="accountID" direction="in">
    </arg>
    <arg type="s" name="uri" direction="in">
    </arg>
</method>

<method name="removeContact" tp:name-for-bindings="removeContact">
    <tp:added version="3.0.0"/>
    <arg type="s" name="accountID" direction="in">
    </arg>
    <arg type="s" name="uri" direction="in">
    </arg>
    <arg type="b" name="ban" direction="in" tp:type="Boolean">
        <tp:docstring>
            True if the the contact should be banned.
            If false, the contact is removed from the contact list (banned or not).
        </tp:docstring>
    </arg>
</method>

Si vols alguns exemples, aquests mètodes s’utilitzen en contactmodel.cpp en LRC.