Types Creation

client/src/lib.rs

@@ -1,5 +1,65 @@
-pub fn add(left: u64, right: u64) -> u64 {
-    left + right
+use mtp_codec::{CommunicationValue, DataTypeId, DataValue, Version};
+use mtp_common::CommunicationError;
+use mtp_transport::{Policy, Receiver, Sender};
+
+/*
+ * The compiled-in protocol version for this client.
+ *
+ * This is set by the `protocol_version` field in `type-maps.yaml`.
+ * At build time, the generated `builtin_type_maps()` determines
+ * which type maps are available, and the client always advertises
+ * the latest one.
+ */
+pub const PROTOCOL_VERSION: Version = Version(2, 0);
+
+/* Client configuration. */
+pub struct ClientConfig {
+    pub url: String,
+    pub server_cert: Option<Vec<u8>>,
+}
+
+// Established MTP connection with a single negotiated version.
+pub struct MTPConnection {
+    pub version: Version,
+    pub sender: Sender,
+    pub receiver: Receiver,
+}
+
+// High-level MTP client.
+pub struct MTPClient;
+
+impl MTPClient {
+    /*
+     * Connect to an MTP host.
+     *
+     * The first message includes the client's protocol version
+     * (a reserved `Version` data entry) so the host can negotiate.
+     */
+    pub async fn connect(
+        config: ClientConfig,
+        client_id: u64,
+    ) -> Result<MTPConnection, CommunicationError> {
+        let (sender, receiver) =
+            mtp_transport::connect(&config.url, config.server_cert, Policy::default()).await?;
+
+        /*
+         * Build the initial identification message with the protocol
+         * version.  Uses only reserved type IDs (0-31), which are
+         * identical across all protocol versions.
+         */
+        let version_str = format!("{}", PROTOCOL_VERSION);
+        let ident = CommunicationValue::new(mtp_codec::CommunicationTypeId(15))
+            .add_data(DataTypeId(3), DataValue::Str(version_str))
+            .add_data(DataTypeId(6), DataValue::UnsignedNumber(client_id.into()));
+
+        sender.send(&ident).await?;
+
+        Ok(MTPConnection {
+            version: PROTOCOL_VERSION,
+            sender,
+            receiver,
+        })
+    }
 }
 
 #[cfg(test)]
@@ -7,8 +67,7 @@ mod tests {
     use super::*;
 
     #[test]
-    fn it_works() {
-        let result = add(2, 2);
-        assert_eq!(result, 4);
+    fn protocol_version_is_compiled_in() {
+        assert_eq!(PROTOCOL_VERSION, Version(2, 0));
     }
 }