add tests for retrying 429 response status codes

CHANGELOG.md

@@ -9,7 +9,7 @@ Versioning].
 
 ## [Unreleased] <!-- #release:date -->
 
-* Automatically retry HTTP requests on status code 429.
+* Automatically retry HTTP requests that return status code 429. (too many requests)
 
 ## [0.11.0] - 2024-03-29
 

Cargo.toml

@@ -38,6 +38,7 @@ tokio = { version = "1.23.0", features = ["macros"] }
 tokio-stream = "0.1.11"
 tracing = "0.1.37"
 tracing-subscriber = { version = "0.3.16", features = ["env-filter"] }
+wiremock = "0.5.19"
 
 [package.metadata.docs.rs]
 all-features = true

src/client.rs

@@ -66,7 +66,8 @@ impl Client {
         url.path_segments_mut()
             .expect("builder validated URL can be a base")
             .extend(path);
-        // All request methods and paths are assumed to be retryable.
+        // All request methods and paths are included to support retries for
+        // 429 status code.
         self.client_retryable
             .request(method, url)
             .bearer_auth(&self.api_key)

src/config.rs

@@ -73,7 +73,7 @@ impl RetryableStrategy for Retry429 {
 impl ClientBuilder {
     /// Sets the policy for retrying failed API calls.
     ///
-    /// Note that the created [`Client`] will retry all API calls.
+    /// Note that the created [`Client`] will retry all API calls that return a 429 status code.
     pub fn with_retry_policy(mut self, policy: ExponentialBackoff) -> Self {
         self.retry_policy = Some(policy);
         self

tests/api.rs

@@ -36,9 +36,11 @@ use futures::stream::TryStreamExt;
 use once_cell::sync::Lazy;
 use rand::Rng;
 use reqwest::StatusCode;
+use reqwest_retry::policies::ExponentialBackoff;
 use test_log::test;
 use tokio::time::{self, Duration};
 use tracing::info;
+use wiremock::{matchers, Mock, MockServer, ResponseTemplate};
 
 use orb_billing::{
     AddIncrementCreditLedgerEntryRequestParams, AddVoidCreditLedgerEntryRequestParams, Address,
@@ -769,3 +771,45 @@ async fn test_errors() {
     let res = client.get_customer_by_external_id("$NOEXIST$").await;
     assert_error_with_status_code(res, StatusCode::NOT_FOUND);
 }
+
+// Tests that 429 responses are retried automatically by the client for API calls
+#[test(tokio::test)]
+async fn test_retry_429() {
+    // Start a mock orb API server and a client configured to target that
+    // server. The retry policy disables backoff to speed up the tests.
+    const MAX_RETRIES: u32 = 3;
+    let server = MockServer::start().await;
+    let client = Client::builder()
+        .with_endpoint(server.uri().parse().unwrap())
+        .with_retry_policy(
+            ExponentialBackoff::builder()
+                .retry_bounds(Duration::from_millis(1), Duration::from_millis(1))
+                .build_with_max_retries(MAX_RETRIES),
+        )
+        .build(ClientConfig { api_key: "".into() });
+
+    // register a mock for the /customers endpoint that returns a 429 response
+    // code. Ensure the client repeatedly retries the API call until giving
+    // up after `MAX_RETRIES` attempts and returning the error.
+    let mock = Mock::given(matchers::method("POST"))
+        .and(matchers::path("/customers"))
+        .respond_with(ResponseTemplate::new(429))
+        .expect(u64::from(MAX_RETRIES) + 1)
+        .named("put customers");
+    server.register(mock).await;
+    let customer_idx = 0;
+    let res = client
+        .create_customer(&CreateCustomerRequest {
+            name: &format!("{TEST_PREFIX}-{customer_idx}"),
+            email: &format!("orb-testing-{customer_idx}@materialize.com"),
+            external_id: None,
+            payment_provider: Some(CustomerPaymentProviderRequest {
+                kind: PaymentProvider::Stripe,
+                id: &format!("cus_fake_{customer_idx}"),
+            }),
+            ..Default::default()
+        })
+        .await;
+
+    assert!(res.is_err());
+}