feat: Expose envconfig functionality through C bridge (#986)

* feat: Expose envconfig functionality through C bridge

* formatting

* more formatting fixes

* improve some test flakiness for envconfig module tests

* feat: Replace callback parameters with options structs in C bridge

- Replace multiple function parameters with ClientConfigLoadOptions and
  ClientConfigProfileLoadOptions structs
- Remove async callbacks and change functions
- Improve documentation to clarify byte array formats
- Add ClientConfigOrFail and ClientConfigProfileOrFail result structs

* Update config TLS  field in C bridge to be Option

* Data in DataSource should be Vec<u8>, remove useless disable_file parameter for ClientConfigLoadOptions

* Use TemporalCoreByteArrayRef instead of string pointers

* Revert misc changes to existing tests

* Add Env prefix befor Config in envconfig c-bridge structs. Run envconfig test using system env vars in separate process

* Skip test is env vars aren't set

* Linter complaint

* remaining lint fixes from cargo 1.88.0 update

* cargo test-lint fix

Author: THardy98

client/src/workflow_handle/mod.rs

@@ -200,8 +200,7 @@ where
                 o => Err(anyhow!(
                     "Server returned an event that didn't match the CloseEvent filter. \
                      This is either a server bug or a new event the SDK does not understand. \
-                     Event details: {:?}",
-                    o
+                     Event details: {o:?}"
                 )),
             };
         }

core-api/src/envconfig.rs

@@ -1592,12 +1592,38 @@ address = "some-address"
 
     #[test]
     fn test_load_client_config_profile_from_system_env() {
-        // Set up system env vars. These tests can't be run in parallel.
-        unsafe {
-            std::env::set_var("TEMPORAL_ADDRESS", "system-address");
-            std::env::set_var("TEMPORAL_NAMESPACE", "system-namespace");
-        }
+        let cargo = std::env::var("CARGO").unwrap_or_else(|_| "cargo".to_string());
+        let output = std::process::Command::new(cargo)
+            .arg("test")
+            .arg("-F")
+            .arg("envconfig")
+            .arg("envconfig::tests::test_load_client_config_profile_from_system_env_impl")
+            .arg("--")
+            .arg("--exact")
+            .arg("--ignored")
+            .env("TEMPORAL_ADDRESS", "system-address")
+            .env("TEMPORAL_NAMESPACE", "system-namespace")
+            .output()
+            .expect("Failed to execute subprocess test");
+
+        assert!(
+            output.status.success(),
+            "Subprocess test failed:\nstdout: {}\nstderr: {}",
+            String::from_utf8_lossy(&output.stdout),
+            String::from_utf8_lossy(&output.stderr),
+        );
+    }
 
+    #[test]
+    #[ignore] // Only run when explicitly called
+    fn test_load_client_config_profile_from_system_env_impl() {
+        // Check if we're in the right context
+        if std::env::var("TEMPORAL_ADDRESS").is_err()
+            || std::env::var("TEMPORAL_NAMESPACE").is_err()
+        {
+            eprintln!("Skipping test - required env vars not set");
+            return; // Early return instead of panic
+        }
         let options = LoadClientConfigProfileOptions {
             disable_file: true, // Don't load from any files
             ..Default::default()
@@ -1607,12 +1633,6 @@ address = "some-address"
         let profile = load_client_config_profile(options, None).unwrap();
         assert_eq!(profile.address.as_ref().unwrap(), "system-address");
         assert_eq!(profile.namespace.as_ref().unwrap(), "system-namespace");
-
-        // Clean up
-        unsafe {
-            std::env::remove_var("TEMPORAL_ADDRESS");
-            std::env::remove_var("TEMPORAL_NAMESPACE");
-        }
     }
 
     #[test]

core-c-bridge/Cargo.toml

@@ -19,6 +19,7 @@ prost = { workspace = true }
 # cause non-determinism.
 rand = "0.9.2"
 rand_pcg = "0.9.0"
+serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 tokio = "1.47"
 tokio-stream = "0.1"
@@ -38,6 +39,7 @@ features = ["ephemeral-server"]
 
 [dependencies.temporal-sdk-core-api]
 path = "../core-api"
+features = ["envconfig"]
 
 [dependencies.temporal-sdk-core-protos]
 path = "../sdk-core-protos"

core-c-bridge/include/temporal-sdk-core-c-bridge.h

@@ -240,6 +240,53 @@ typedef void (*TemporalCoreClientRpcCallCallback)(void *user_data,
                                                   const struct TemporalCoreByteArray *failure_message,
                                                   const struct TemporalCoreByteArray *failure_details);
 
+/**
+ * OrFail result for client config loading operations.
+ * Either success or fail will be null, but never both.
+ * If success is not null, it contains JSON-serialized client configuration data.
+ * If fail is not null, it contains UTF-8 encoded error message.
+ * The returned ByteArrays must be freed by the caller.
+ */
+typedef struct TemporalCoreClientEnvConfigOrFail {
+  const struct TemporalCoreByteArray *success;
+  const struct TemporalCoreByteArray *fail;
+} TemporalCoreClientEnvConfigOrFail;
+
+/**
+ * Options for loading client configuration.
+ */
+typedef struct TemporalCoreClientEnvConfigLoadOptions {
+  struct TemporalCoreByteArrayRef path;
+  struct TemporalCoreByteArrayRef data;
+  bool config_file_strict;
+  struct TemporalCoreByteArrayRef env_vars;
+} TemporalCoreClientEnvConfigLoadOptions;
+
+/**
+ * OrFail result for client config profile loading operations.
+ * Either success or fail will be null, but never both.
+ * If success is not null, it contains JSON-serialized client configuration profile data.
+ * If fail is not null, it contains UTF-8 encoded error message.
+ * The returned ByteArrays must be freed by the caller.
+ */
+typedef struct TemporalCoreClientEnvConfigProfileOrFail {
+  const struct TemporalCoreByteArray *success;
+  const struct TemporalCoreByteArray *fail;
+} TemporalCoreClientEnvConfigProfileOrFail;
+
+/**
+ * Options for loading a specific client configuration profile.
+ */
+typedef struct TemporalCoreClientEnvConfigProfileLoadOptions {
+  struct TemporalCoreByteArrayRef profile;
+  struct TemporalCoreByteArrayRef path;
+  struct TemporalCoreByteArrayRef data;
+  bool disable_file;
+  bool disable_env;
+  bool config_file_strict;
+  struct TemporalCoreByteArrayRef env_vars;
+} TemporalCoreClientEnvConfigProfileLoadOptions;
+
 typedef union TemporalCoreMetricAttributeValue {
   struct TemporalCoreByteArrayRef string_value;
   int64_t int_value;
@@ -771,6 +818,20 @@ void temporal_core_client_rpc_call(struct TemporalCoreClient *client,
                                    void *user_data,
                                    TemporalCoreClientRpcCallCallback callback);
 
+/**
+ * Load all client profiles from given sources.
+ * Returns ClientConfigOrFail with either success JSON or error message.
+ * The returned ByteArrays must be freed by the caller.
+ */
+struct TemporalCoreClientEnvConfigOrFail temporal_core_client_env_config_load(const struct TemporalCoreClientEnvConfigLoadOptions *options);
+
+/**
+ * Load a single client profile from given sources with env overrides.
+ * Returns ClientConfigProfileOrFail with either success JSON or error message.
+ * The returned ByteArrays must be freed by the caller.
+ */
+struct TemporalCoreClientEnvConfigProfileOrFail temporal_core_client_env_config_profile_load(const struct TemporalCoreClientEnvConfigProfileLoadOptions *options);
+
 struct TemporalCoreMetricMeter *temporal_core_metric_meter_new(struct TemporalCoreRuntime *runtime);
 
 void temporal_core_metric_meter_free(struct TemporalCoreMetricMeter *meter);

core-c-bridge/src/client.rs

@@ -685,7 +685,7 @@ async fn call_workflow_service(
         "UpdateWorkerBuildIdCompatibility" => {
             rpc_call!(client, call, update_worker_build_id_compatibility)
         }
-        rpc => Err(anyhow::anyhow!("Unknown RPC call {}", rpc)),
+        rpc => Err(anyhow::anyhow!("Unknown RPC call {rpc}")),
     }
 }
 
@@ -715,7 +715,7 @@ async fn call_operator_service(
         "UpdateNexusEndpoint" => {
             rpc_call_on_trait!(client, call, OperatorService, update_nexus_endpoint)
         }
-        rpc => Err(anyhow::anyhow!("Unknown RPC call {}", rpc)),
+        rpc => Err(anyhow::anyhow!("Unknown RPC call {rpc}")),
     }
 }
 
@@ -785,7 +785,7 @@ async fn call_cloud_service(client: &CoreClient, call: &RpcCallOptions) -> anyho
         "GetConnectivityRule" => rpc_call!(client, call, get_connectivity_rule),
         "GetConnectivityRules" => rpc_call!(client, call, get_connectivity_rules),
         "DeleteConnectivityRule" => rpc_call!(client, call, delete_connectivity_rule),
-        rpc => Err(anyhow::anyhow!("Unknown RPC call {}", rpc)),
+        rpc => Err(anyhow::anyhow!("Unknown RPC call {rpc}")),
     }
 }
 
@@ -799,7 +799,7 @@ async fn call_test_service(client: &CoreClient, call: &RpcCallOptions) -> anyhow
         "Sleep" => rpc_call!(client, call, sleep),
         "UnlockTimeSkippingWithSleep" => rpc_call!(client, call, unlock_time_skipping_with_sleep),
         "UnlockTimeSkipping" => rpc_call!(client, call, unlock_time_skipping),
-        rpc => Err(anyhow::anyhow!("Unknown RPC call {}", rpc)),
+        rpc => Err(anyhow::anyhow!("Unknown RPC call {rpc}")),
     }
 }
 
@@ -814,7 +814,7 @@ async fn call_health_service(
         "Watch" => Err(anyhow::anyhow!(
             "Health service Watch method is not implemented in C bridge"
         )),
-        rpc => Err(anyhow::anyhow!("Unknown RPC call {}", rpc)),
+        rpc => Err(anyhow::anyhow!("Unknown RPC call {rpc}")),
     }
 }