fix: Accept config to be through file or env vars

Author: carlosvdr

config/src/config.rs

@@ -68,12 +68,16 @@ impl ConfigPrefix {
 }
 
 impl Config {
-    pub fn parse(prefix: ConfigPrefix, filename: &PathBuf) -> Result<Self, String> {
+    pub fn parse(prefix: ConfigPrefix, filename: &Option<PathBuf>) -> Result<Self, String> {
         let config_defaults = include_str!("../default_values.toml");
 
-        let config: ConfigWrapper = Figment::new()
-            .merge(Toml::string(config_defaults))
-            .merge(Toml::file(filename))
+        let mut figment_config = Figment::new().merge(Toml::string(config_defaults));
+
+        if let Some(path) = filename {
+            figment_config = figment_config.merge(Toml::file(path));
+        }
+
+        let config: ConfigWrapper = figment_config
             .merge(Env::prefixed(prefix.get_prefix()).split("__"))
             .extract()
             .map_err(|e| e.to_string())?;
@@ -349,7 +353,7 @@ mod tests {
     fn test_minimal_config() {
         Config::parse(
             ConfigPrefix::Service,
-            &PathBuf::from("minimal-config-example.toml"),
+            &Some(PathBuf::from("minimal-config-example.toml")),
         )
         .unwrap();
     }
@@ -359,7 +363,7 @@ mod tests {
         // Generate full config by deserializing the minimal config and let the code fill in the defaults.
         let max_config = Config::parse(
             ConfigPrefix::Service,
-            &PathBuf::from("minimal-config-example.toml"),
+            &Some(PathBuf::from("minimal-config-example.toml")),
         )
         .unwrap();
         let max_config_file: Config = toml::from_str(
@@ -381,7 +385,7 @@ mod tests {
 
         Config::parse(
             ConfigPrefix::Service,
-            &PathBuf::from("minimal-config-example.toml"),
+            &Some(PathBuf::from("minimal-config-example.toml")),
         )
         .unwrap();
 
@@ -421,7 +425,7 @@ mod tests {
         // This should fail because the subgraphs.network.query_url field is missing
         Config::parse(
             ConfigPrefix::Service,
-            &PathBuf::from(temp_minimal_config_path.path()),
+            &Some(PathBuf::from(temp_minimal_config_path.path())),
         )
         .unwrap_err();
 
@@ -430,7 +434,7 @@ mod tests {
 
         let config = Config::parse(
             ConfigPrefix::Service,
-            &PathBuf::from(temp_minimal_config_path.path()),
+            &Some(PathBuf::from(temp_minimal_config_path.path())),
         )
         .unwrap();
 
@@ -448,7 +452,7 @@ mod tests {
 
         let config = Config::parse(
             ConfigPrefix::Service,
-            &PathBuf::from("minimal-config-example.toml"),
+            &Some(PathBuf::from("minimal-config-example.toml")),
         )
         .unwrap();
 
@@ -533,7 +537,7 @@ mod tests {
         // Parse the config with new datbase vars
         let config = Config::parse(
             ConfigPrefix::Service,
-            &PathBuf::from(temp_minimal_config_path.path()),
+            &Some(PathBuf::from(temp_minimal_config_path.path())),
         )
         .unwrap();
 

service/src/cli.rs

@@ -10,5 +10,5 @@ pub struct Cli {
     /// Path to the configuration file.
     /// See https://github.com/graphprotocol/indexer-rs/tree/main/service for examples.
     #[arg(long, value_name = "FILE", verbatim_doc_comment)]
-    pub config: PathBuf,
+    pub config: Option<PathBuf>,
 }

service/src/service.rs

@@ -133,7 +133,7 @@ pub async fn run() -> anyhow::Result<()> {
         MainConfig::parse(indexer_config::ConfigPrefix::Service, &cli.config).map_err(|e| {
             error!(
                 "Invalid configuration file `{}`: {}",
-                cli.config.display(),
+                cli.config.unwrap_or_default().display(),
                 e
             );
             anyhow!(e)

tap-agent/src/config.rs

@@ -17,7 +17,7 @@ pub struct Cli {
     /// Path to the configuration file.
     /// See https://github.com/graphprotocol/indexer-rs/tree/main/tap-agent for examples.
     #[arg(long, value_name = "FILE", verbatim_doc_comment)]
-    pub config: PathBuf,
+    pub config: Option<PathBuf>,
 }
 
 impl From<IndexerConfig> for Config {