test(policy-server): Run proxy tests serially

This way they don't compete for docker resources on CI.

Signed-off-by: Víctor Cuadrado Juan <vcuadradojuan@suse.de>

Author: viccuad

Cargo.lock

@@ -67,6 +67,7 @@ tokio-stream = "0.1.18"
 
 [dev-dependencies]
 backon         = { version = "1.6", features = ["tokio-sleep"] }
+serial_test    = "3"
 http-body-util = "0.1.3"
 mockall        = "0.14"
 rcgen          = { version = "0.14", features = ["crypto"] }

crates/policy-server/Cargo.toml

@@ -1305,8 +1305,6 @@ fn build_request_client(
 
 // helper functions for testing proxy functionality
 mod proxy_helpers {
-    use std::time::Duration;
-
     use backon::{ConstantBuilder, Retryable};
     use testcontainers::{
         ContainerAsync, GenericImage,
@@ -1348,8 +1346,8 @@ mod proxy_helpers {
         check
             .retry(
                 ConstantBuilder::default()
-                    .with_delay(std::time::Duration::from_millis(100))
-                    .with_max_times(5),
+                    .with_delay(std::time::Duration::from_millis(500))
+                    .with_max_times(20),
             )
             .await
             .is_ok()
@@ -1359,6 +1357,7 @@ mod proxy_helpers {
 #[rstest]
 #[case::both_http_and_https_proxy(true)]
 #[case::https_proxy_only(false)]
+#[serial_test::serial]
 #[tokio::test]
 async fn test_policy_server_with_https_proxy(#[case] set_http_proxy: bool) {
     use proxy_helpers::*;
@@ -1415,6 +1414,7 @@ async fn test_policy_server_with_https_proxy(#[case] set_http_proxy: bool) {
 /// source. The policy is first fetched from ghcr.io, pushed to the local registry, then the policy
 /// server is started with HTTP_PROXY pointing at tinyproxy. Both containers share the default
 /// docker bridge network so the proxy can forward requests to the registry by its bridge IP.
+#[serial_test::serial]
 #[tokio::test]
 async fn test_policy_server_with_http_proxy() {
     use proxy_helpers::*;
@@ -1518,6 +1518,7 @@ async fn test_policy_server_with_http_proxy() {
 /// A real tinyproxy is started and set as HTTPS_PROXY. With NO_PROXY=ghcr.io the policy server
 /// must connect directly to ghcr.io, so startup and validation succeed and the proxy logs must not
 /// contain any reference to ghcr.io.
+#[serial_test::serial]
 #[tokio::test]
 async fn test_policy_server_with_no_proxy() {
     use proxy_helpers::*;