From a78a52eb6aefa682cc7b4424df53184c124b1355 Mon Sep 17 00:00:00 2001
From: Alexandre Gomez <gomez.a.corneille@gmail.com>
Date: Sat, 20 Aug 2022 21:48:28 +0200
Subject: [PATCH] feat: implement grpc client

Signed-off-by: Alexandre Gomez <gomez.a.corneille@gmail.com>
---
 controller/lib/src/grpc_client/interface.rs | 124 ++++++++++++++++++++
 controller/lib/src/grpc_client/mod.rs       |   1 +
 controller/lib/src/lib.rs                   |   1 +
 3 files changed, 126 insertions(+)
 create mode 100644 controller/lib/src/grpc_client/interface.rs
 create mode 100644 controller/lib/src/grpc_client/mod.rs

diff --git a/controller/lib/src/grpc_client/interface.rs b/controller/lib/src/grpc_client/interface.rs
new file mode 100644
index 00000000..3f93a53b
--- /dev/null
+++ b/controller/lib/src/grpc_client/interface.rs
@@ -0,0 +1,124 @@
+use log::{error, info};
+use proto::scheduler::instance_service_client::InstanceServiceClient;
+use proto::scheduler::{Instance, InstanceIdentifier, InstanceStatus};
+use tonic::transport::{Channel, Error};
+use tonic::{Request, Response, Status, Streaming};
+
+#[derive(Debug)]
+pub enum SchedulerClientInterfaceError {
+    ConnectionError(Error),
+    RequestFailed(Status),
+}
+
+pub struct SchedulerClientInterface {
+    instance_client: InstanceServiceClient<Channel>,
+}
+
+impl SchedulerClientInterface {
+    pub async fn new(
+        instance_client_address: String,
+    ) -> Result<Self, SchedulerClientInterfaceError> {
+        info!(
+            "Starting gRPC client for scheduler Instance Service on {}",
+            instance_client_address,
+        );
+
+        let instance_client = InstanceServiceClient::connect(instance_client_address)
+            .await
+            .map_err(SchedulerClientInterfaceError::ConnectionError)?;
+
+        Ok(Self { instance_client })
+    }
+
+    pub async fn create_instance(
+        &mut self,
+        request: Request<Instance>,
+    ) -> Result<Response<Streaming<InstanceStatus>>, SchedulerClientInterfaceError> {
+        let remote_address = match request.remote_addr() {
+            Some(addr) => addr.to_string(),
+            None => {
+                error!("\"create_instance\" Failed to get remote address from request");
+                "Error getting address".to_string()
+            }
+        };
+
+        info!(
+            "Calling gRPC procedure \"create_instance\" to {}",
+            remote_address
+        );
+
+        self.instance_client
+            .create(request)
+            .await
+            .map_err(SchedulerClientInterfaceError::RequestFailed)
+    }
+
+    pub async fn destroy_instance(
+        &mut self,
+        request: Request<InstanceIdentifier>,
+    ) -> Result<Response<()>, SchedulerClientInterfaceError> {
+        let remote_address = match request.remote_addr() {
+            Some(addr) => addr.to_string(),
+            None => {
+                error!("\"create_instance\" Failed to get remote address from request");
+                "Error getting address".to_string()
+            }
+        };
+
+        info!(
+            "Calling gRPC procedure \"destroy_instance\" to {}",
+            remote_address
+        );
+
+        self.instance_client
+            .destroy(request)
+            .await
+            .map_err(SchedulerClientInterfaceError::RequestFailed)
+    }
+
+    pub async fn start_instance(
+        &mut self,
+        request: Request<InstanceIdentifier>,
+    ) -> Result<Response<()>, SchedulerClientInterfaceError> {
+        let remote_address = match request.remote_addr() {
+            Some(addr) => addr.to_string(),
+            None => {
+                error!("\"create_instance\" Failed to get remote address from request");
+                "Error getting address".to_string()
+            }
+        };
+
+        info!(
+            "Calling gRPC procedure \"start_instance\" to {}",
+            remote_address
+        );
+
+        self.instance_client
+            .start(request)
+            .await
+            .map_err(SchedulerClientInterfaceError::RequestFailed)
+    }
+
+    pub async fn stop_instance(
+        &mut self,
+        request: Request<InstanceIdentifier>,
+    ) -> Result<Response<()>, SchedulerClientInterfaceError> {
+        let remote_address = match request.remote_addr() {
+            Some(addr) => addr.to_string(),
+            None => {
+                error!("\"create_instance\" Failed to get remote address from request");
+                "Error getting address".to_string()
+            }
+        };
+
+        info!(
+            "Calling gRPC procedure \"stop_instance\" to {}",
+            remote_address
+        );
+
+        self.instance_client
+            .stop(request)
+            .await
+            .map_err(SchedulerClientInterfaceError::RequestFailed)
+    }
+}
diff --git a/controller/lib/src/grpc_client/mod.rs b/controller/lib/src/grpc_client/mod.rs
new file mode 100644
index 00000000..8d3d626b
--- /dev/null
+++ b/controller/lib/src/grpc_client/mod.rs
@@ -0,0 +1 @@
+pub mod interface;
diff --git a/controller/lib/src/lib.rs b/controller/lib/src/lib.rs
index 91866edd..1bacc8d0 100644
--- a/controller/lib/src/lib.rs
+++ b/controller/lib/src/lib.rs
@@ -1,2 +1,3 @@
 pub mod external_api;
+pub mod grpc_client;
 pub mod internal_api;