From a4372e01890537695932f5c9042a8e884a810d23 Mon Sep 17 00:00:00 2001
From: Adam Chalmers <achalmers@cloudflare.com>
Date: Thu, 9 Jan 2020 12:13:04 -0600
Subject: [PATCH] Trait for async API clients. Mock now implements the async
 API client trait too.

---
 cloudflare-e2e-test/src/main.rs       | 16 ++++++++---
 cloudflare/Cargo.toml                 |  1 +
 cloudflare/src/framework/apiclient.rs |  1 +
 cloudflare/src/framework/async_api.rs | 22 +++++++++++++---
 cloudflare/src/framework/mock.rs      | 38 +++++++++++++++++++--------
 5 files changed, 59 insertions(+), 19 deletions(-)

diff --git a/cloudflare-e2e-test/src/main.rs b/cloudflare-e2e-test/src/main.rs
index fc4f6c1c..adff5118 100644
--- a/cloudflare-e2e-test/src/main.rs
+++ b/cloudflare-e2e-test/src/main.rs
@@ -1,16 +1,24 @@
 use clap::{App, AppSettings, Arg};
-use cloudflare::framework::{async_api, auth::Credentials, Environment, HttpApiClientConfig};
+use cloudflare::framework::{
+    async_api, async_api::ApiClient, auth::Credentials, Environment, HttpApiClientConfig,
+};
 use failure::{Error, Fallible};
 use std::fmt::Display;
 use std::net::{IpAddr, Ipv4Addr};
 
-async fn tests(api_client: &async_api::Client, account_id: &str) -> Fallible<()> {
-    test_lb_pool(&api_client, &account_id).await?;
+async fn tests<ApiClientType: ApiClient>(
+    api_client: &ApiClientType,
+    account_id: &str,
+) -> Fallible<()> {
+    test_lb_pool(api_client, &account_id).await?;
     println!("Tests passed");
     Ok(())
 }
 
-async fn test_lb_pool(api_client: &async_api::Client, account_identifier: &str) -> Fallible<()> {
+async fn test_lb_pool<ApiClientType: ApiClient>(
+    api_client: &ApiClientType,
+    account_identifier: &str,
+) -> Fallible<()> {
     use cloudflare::endpoints::load_balancing::*;
 
     // Create a pool
diff --git a/cloudflare/Cargo.toml b/cloudflare/Cargo.toml
index ada1c989..e8d5e7f4 100644
--- a/cloudflare/Cargo.toml
+++ b/cloudflare/Cargo.toml
@@ -9,6 +9,7 @@ categories = ["api-bindings", "web-programming::http-client"]
 license = "BSD-3-Clause"
 
 [dependencies]
+async-trait = "0.1.22"
 chrono = { version = "0.4", features = ["serde"] }
 http = "0.1.18"
 reqwest = { version = "0.10", features = ["json", "blocking"] }
diff --git a/cloudflare/src/framework/apiclient.rs b/cloudflare/src/framework/apiclient.rs
index abb4db04..654b5183 100644
--- a/cloudflare/src/framework/apiclient.rs
+++ b/cloudflare/src/framework/apiclient.rs
@@ -1,3 +1,4 @@
+//! This module contains the synchronous (blocking) API client.
 use crate::framework::{
     endpoint::Endpoint,
     response::{ApiResponse, ApiResult},
diff --git a/cloudflare/src/framework/async_api.rs b/cloudflare/src/framework/async_api.rs
index d3789038..beb01462 100644
--- a/cloudflare/src/framework/async_api.rs
+++ b/cloudflare/src/framework/async_api.rs
@@ -7,9 +7,22 @@ use crate::framework::{
     response::{ApiResponse, ApiResult},
     Environment, HttpApiClientConfig,
 };
+use async_trait::async_trait;
 use reqwest;
 use serde::Serialize;
 
+#[async_trait]
+pub trait ApiClient {
+    async fn request<ResultType, QueryType, BodyType>(
+        &self,
+        endpoint: &(dyn Endpoint<ResultType, QueryType, BodyType> + Send + Sync),
+    ) -> ApiResponse<ResultType>
+    where
+        ResultType: ApiResult,
+        QueryType: Serialize,
+        BodyType: Serialize;
+}
+
 /// A Cloudflare API client that makes requests asynchronously.
 pub struct Client {
     environment: Environment,
@@ -42,12 +55,13 @@ impl Client {
             http_client,
         })
     }
+}
 
-    // Currently, futures/async fns aren't supported in traits, and won't be for a while.
-    // So unlike ApiClient/HttpApiClient, there's no trait with the request method.
-    pub async fn request<ResultType, QueryType, BodyType>(
+#[async_trait]
+impl ApiClient for Client {
+    async fn request<ResultType, QueryType, BodyType>(
         &self,
-        endpoint: &dyn Endpoint<ResultType, QueryType, BodyType>,
+        endpoint: &(dyn Endpoint<ResultType, QueryType, BodyType> + Send + Sync),
     ) -> ApiResponse<ResultType>
     where
         ResultType: ApiResult,
diff --git a/cloudflare/src/framework/mock.rs b/cloudflare/src/framework/mock.rs
index dd68217e..9192f215 100644
--- a/cloudflare/src/framework/mock.rs
+++ b/cloudflare/src/framework/mock.rs
@@ -1,6 +1,8 @@
 use crate::framework::apiclient::ApiClient;
+use crate::framework::async_api;
 use crate::framework::endpoint::{Endpoint, Method};
 use crate::framework::response::{ApiError, ApiErrors, ApiFailure, ApiResponse, ApiResult};
+use async_trait::async_trait;
 use reqwest;
 use std::collections::HashMap;
 
@@ -22,21 +24,35 @@ impl Endpoint<NoopResult> for NoopEndpoint {
 pub struct NoopResult {}
 impl ApiResult for NoopResult {}
 
+fn mock_response() -> ApiFailure {
+    ApiFailure::Error(
+        reqwest::StatusCode::INTERNAL_SERVER_ERROR,
+        ApiErrors {
+            errors: vec![ApiError {
+                code: 9999,
+                message: "This is a mocked failure response".to_owned(),
+                other: HashMap::new(),
+            }],
+            other: HashMap::new(),
+        },
+    )
+}
+
 impl ApiClient for MockApiClient {
     fn request<ResultType, QueryType, BodyType>(
         &self,
         _endpoint: &dyn Endpoint<ResultType, QueryType, BodyType>,
     ) -> ApiResponse<ResultType> {
-        Err(ApiFailure::Error(
-            reqwest::StatusCode::INTERNAL_SERVER_ERROR,
-            ApiErrors {
-                errors: vec![ApiError {
-                    code: 9999,
-                    message: "This is a mocked failure response".to_owned(),
-                    other: HashMap::new(),
-                }],
-                other: HashMap::new(),
-            },
-        ))
+        Err(mock_response())
+    }
+}
+
+#[async_trait]
+impl async_api::ApiClient for MockApiClient {
+    async fn request<ResultType, QueryType, BodyType>(
+        &self,
+        _endpoint: &(dyn Endpoint<ResultType, QueryType, BodyType> + Send + Sync),
+    ) -> ApiResponse<ResultType> {
+        Err(mock_response())
     }
 }