From fc0d8ee8e725b351c1902dd7d0f92a8cc95b5048 Mon Sep 17 00:00:00 2001
From: Isaiah Inuwa <isaiah.inuwa@gmail.com>
Date: Mon, 17 Feb 2020 20:45:46 -0600
Subject: [PATCH] Add send-to-device endpoint

---
 CHANGELOG.md                                  |  1 +
 src/r0.rs                                     |  1 +
 src/r0/client_exchange.rs                     | 71 +++++++++++++++++++
 .../client_exchange/send_event_to_device.rs   | 36 ++++++++++
 4 files changed, 109 insertions(+)
 create mode 100644 src/r0/client_exchange.rs
 create mode 100644 src/r0/client_exchange/send_event_to_device.rs

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1826ebd9..15cb638e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,7 @@ Improvements:
 
 * Add an `Error` type that represents the well-known errors in the client-server API
 * Add OpenID token request endpoint.
+* Add `r0::client_exchange::send_event_to_device` (introduced in r0.3.0)
 
 Breaking changes:
 
diff --git a/src/r0.rs b/src/r0.rs
index 79123f05..9ed2405f 100644
--- a/src/r0.rs
+++ b/src/r0.rs
@@ -4,6 +4,7 @@ pub mod account;
 pub mod alias;
 pub mod appservice;
 pub mod capabilities;
+pub mod client_exchange;
 pub mod config;
 pub mod contact;
 pub mod context;
diff --git a/src/r0/client_exchange.rs b/src/r0/client_exchange.rs
new file mode 100644
index 00000000..033d0fd1
--- /dev/null
+++ b/src/r0/client_exchange.rs
@@ -0,0 +1,71 @@
+//! Endpoints for client devices to exchange information not persisted in room DAG.
+
+use std::{
+    convert::TryFrom,
+    fmt::{Display, Formatter, Result as FmtResult},
+};
+
+use ruma_identifiers::DeviceId;
+use serde::{
+    de::{self, Unexpected},
+    Deserialize, Deserializer, Serialize, Serializer,
+};
+
+pub mod send_event_to_device;
+/// Represents one or all of a user's devices.
+#[derive(Clone, Debug, Hash, PartialEq, Eq)]
+pub enum DeviceIdOrAllDevices {
+    /// Represents a device Id for one of a user's devices.
+    DeviceId(DeviceId),
+    /// Represents all devices for a user.
+    AllDevices,
+}
+
+impl Display for DeviceIdOrAllDevices {
+    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
+        match self {
+            DeviceIdOrAllDevices::DeviceId(device_id) => write!(f, "{}", device_id.to_string()),
+            DeviceIdOrAllDevices::AllDevices => write!(f, "*"),
+        }
+    }
+}
+
+impl TryFrom<&str> for DeviceIdOrAllDevices {
+    type Error = &'static str;
+    fn try_from(device_id_or_all_devices: &str) -> Result<Self, Self::Error> {
+        if device_id_or_all_devices.is_empty() {
+            Err("Device identifier cannot be empty")
+        } else if "*" == device_id_or_all_devices {
+            Ok(DeviceIdOrAllDevices::AllDevices)
+        } else {
+            Ok(DeviceIdOrAllDevices::DeviceId(
+                device_id_or_all_devices.to_string(),
+            ))
+        }
+    }
+}
+
+impl Serialize for DeviceIdOrAllDevices {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        match self {
+            Self::DeviceId(ref device_id) => serializer.serialize_str(&device_id),
+            Self::AllDevices => serializer.serialize_str("*"),
+        }
+    }
+}
+
+impl<'de> Deserialize<'de> for DeviceIdOrAllDevices {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        let value = &String::deserialize(deserializer)?;
+
+        DeviceIdOrAllDevices::try_from(&value[..]).map_err(|_| {
+            de::Error::invalid_value(Unexpected::Str(&value), &"a valid device identifier or '*'")
+        })
+    }
+}
diff --git a/src/r0/client_exchange/send_event_to_device.rs b/src/r0/client_exchange/send_event_to_device.rs
new file mode 100644
index 00000000..36aefd36
--- /dev/null
+++ b/src/r0/client_exchange/send_event_to_device.rs
@@ -0,0 +1,36 @@
+//! [PUT /_matrix/client/r0/sendToDevice/{eventType}/{txnId}](https://matrix.org/docs/spec/client_server/r0.6.0#put-matrix-client-r0-sendtodevice-eventtype-txnid)
+
+use std::collections::HashMap;
+
+use ruma_api::ruma_api;
+use ruma_events::{collections::all, EventResult};
+use ruma_identifiers::UserId;
+
+use super::DeviceIdOrAllDevices;
+
+ruma_api! {
+    metadata {
+        description: "Send an event to a device or devices.",
+        method: PUT,
+        name: "send_event_to_device",
+        path: "/_matrix/client/r0/sendToDevice/:event_type/:txn_id",
+        rate_limited: false,
+        requires_authentication: true,
+    }
+
+    request {
+        /// Type of event being sent to each device.
+        #[ruma_api(path)]
+        event_type: String,
+        /// A request identifier unique to the access token used to send the request.
+        #[ruma_api(path)]
+        txn_id: String,
+        /// A map of users to devices to a message event to be sent to the user's
+        /// device. Individual message events can be sent to devices, but all
+        /// events must be of the same type.
+        #[wrap_incoming(all::Event with EventResult)]
+        messages: HashMap<UserId, HashMap<DeviceIdOrAllDevices, all::Event>>
+    }
+
+    response {}
+}