From 8351858be7e3e58354288445583d3d45b533eb40 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Damir=20Jeli=C4=87?= <poljar@termina.org.uk>
Date: Wed, 12 Aug 2020 12:48:22 +0200
Subject: [PATCH] crypto: Expose a method to get a users device.

---
 matrix_sdk_crypto/Cargo.toml     |  1 +
 matrix_sdk_crypto/src/machine.rs | 38 ++++++++++++++++++++++++++++++--
 2 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/matrix_sdk_crypto/Cargo.toml b/matrix_sdk_crypto/Cargo.toml
index 64f2d2f3..d532a09d 100644
--- a/matrix_sdk_crypto/Cargo.toml
+++ b/matrix_sdk_crypto/Cargo.toml
@@ -46,6 +46,7 @@ features = ["runtime-tokio", "sqlite"]
 
 [dev-dependencies]
 tokio = { version = "0.2.22", features = ["rt-threaded", "macros"] }
+futures = "0.3.5"
 proptest = "0.10.0"
 serde_json = "1.0.57"
 tempfile = "3.1.0"
diff --git a/matrix_sdk_crypto/src/machine.rs b/matrix_sdk_crypto/src/machine.rs
index 7cad462b..7a5486bf 100644
--- a/matrix_sdk_crypto/src/machine.rs
+++ b/matrix_sdk_crypto/src/machine.rs
@@ -23,6 +23,8 @@ use std::{
 };
 
 use dashmap::DashMap;
+use serde_json::Value;
+use tracing::{debug, error, info, instrument, trace, warn};
 
 use api::r0::{
     keys::{claim_keys, get_keys, upload_keys, DeviceKeys, OneTimeKey},
@@ -44,8 +46,6 @@ use matrix_sdk_common::{
     uuid::Uuid,
     Raw,
 };
-use serde_json::Value;
-use tracing::{debug, error, info, instrument, trace, warn};
 
 #[cfg(feature = "sqlite-cryptostore")]
 use super::store::sqlite::SqliteStore;
@@ -1231,6 +1231,40 @@ impl OlmMachine {
     pub async fn users_for_key_query(&self) -> HashSet<UserId> {
         self.store.users_for_key_query()
     }
+
+    /// Get a specific device of a user.
+    ///
+    /// # Arguments
+    ///
+    /// * `user_id` - The unique id of the user that the device belongs to.
+    ///
+    /// * `device_id` - The unique id of the device.
+    ///
+    /// Returns a `Device` if one is found and the crypto store didn't throw an
+    /// error.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// # use std::convert::TryFrom;
+    /// # use matrix_sdk_crypto::OlmMachine;
+    /// # use matrix_sdk_common::identifiers::UserId;
+    /// # use futures::executor::block_on;
+    /// # let alice = UserId::try_from("@alice:example.org").unwrap();
+    /// # let machine = OlmMachine::new(&alice, "DEVICEID".into());
+    /// # block_on(async {
+    /// let device = machine.get_device(&alice, "DEVICEID".into()).await;
+    ///
+    /// println!("{:?}", device);
+    /// # });
+    /// ```
+    pub async fn get_device(&self, user_id: &UserId, device_id: &DeviceId) -> Option<Device> {
+        self.store
+            .get_device(user_id, device_id)
+            .await
+            .ok()
+            .flatten()
+    }
 }
 
 #[cfg(test)]