Merge pull request #211 from apollographql/GT-317

Author: DaleSeo

crates/apollo-mcp-server/src/main.rs

@@ -38,11 +38,10 @@ struct Args {
 
 #[tokio::main]
 async fn main() -> anyhow::Result<()> {
-    let config: runtime::Config = Args::parse()
-        .config
-        .map(runtime::read_config)
-        .transpose()?
-        .unwrap_or_default();
+    let config: runtime::Config = match Args::parse().config {
+        Some(config_path) => runtime::read_config(config_path)?,
+        None => runtime::read_config_from_env().unwrap_or_default(),
+    };
 
     let mut env_filter = EnvFilter::from_default_env().add_directive(config.logging.level.into());
 

crates/apollo-mcp-server/src/runtime.rs

@@ -26,6 +26,15 @@ pub use schema_source::SchemaSource;
 /// Separator to use when drilling down into nested options in the env figment
 const ENV_NESTED_SEPARATOR: &str = "__";
 
+/// Read configuration from environment variables only (when no config file is provided)
+#[allow(clippy::result_large_err)]
+pub fn read_config_from_env() -> Result<Config, figment::Error> {
+    Figment::new()
+        .join(apollo_common_env())
+        .join(Env::prefixed("APOLLO_MCP_").split(ENV_NESTED_SEPARATOR))
+        .extract()
+}
+
 /// Read in a config from a YAML file, filling in any missing values from the environment
 #[allow(clippy::result_large_err)]
 pub fn read_config(yaml_path: impl AsRef<Path>) -> Result<Config, figment::Error> {