datasynth_server/
config_loader.rs

1//! External config loading for multi-instance deployments.
2//!
3//! Supports loading configuration from file, URL, inline string, or defaults.
4
5use datasynth_config::schema::GeneratorConfig;
6use serde::{Deserialize, Serialize};
7use std::path::PathBuf;
8use std::sync::Arc;
9use tokio::sync::RwLock;
10use tracing::info;
11
12/// Source for loading configuration.
13#[derive(Debug, Clone, Default, Serialize, Deserialize)]
14#[serde(tag = "type", rename_all = "snake_case")]
15pub enum ConfigSource {
16    /// Load from a YAML file.
17    File { path: PathBuf },
18    /// Load from a URL (HTTP GET) - requires an external fetch.
19    Url { url: String },
20    /// Inline YAML/JSON string.
21    Inline { content: String },
22    /// Use default configuration.
23    #[default]
24    Default,
25}
26
27/// Loads a GeneratorConfig from the specified source.
28pub async fn load_config(source: &ConfigSource) -> Result<GeneratorConfig, ConfigLoadError> {
29    match source {
30        ConfigSource::File { path } => {
31            info!("Loading config from file: {}", path.display());
32            let content = tokio::fs::read_to_string(path).await.map_err(|e| {
33                ConfigLoadError::Io(format!("Failed to read {}: {}", path.display(), e))
34            })?;
35            let config: GeneratorConfig = serde_yaml::from_str(&content)
36                .map_err(|e| ConfigLoadError::Parse(format!("Failed to parse YAML: {}", e)))?;
37            Ok(config)
38        }
39        ConfigSource::Url { url } => {
40            // URL loading uses a simple blocking HTTP client to avoid adding reqwest dependency
41            info!("Loading config from URL: {}", url);
42            Err(ConfigLoadError::Io(format!(
43                "URL config loading not yet supported. Use file or inline config instead. URL: {}",
44                url
45            )))
46        }
47        ConfigSource::Inline { content } => {
48            info!("Loading inline config ({} bytes)", content.len());
49            let config: GeneratorConfig = serde_yaml::from_str(content)
50                .map_err(|e| ConfigLoadError::Parse(format!("Failed to parse YAML: {}", e)))?;
51            Ok(config)
52        }
53        ConfigSource::Default => {
54            info!("Using default generator config");
55            Ok(crate::grpc::service::default_generator_config())
56        }
57    }
58}
59
60/// Reloads configuration from a source into shared state.
61pub async fn reload_config(
62    source: &ConfigSource,
63    config_lock: &Arc<RwLock<GeneratorConfig>>,
64) -> Result<(), ConfigLoadError> {
65    let new_config = load_config(source).await?;
66    let mut config = config_lock.write().await;
67    *config = new_config;
68    info!("Configuration reloaded successfully");
69    Ok(())
70}
71
72/// Error type for config loading.
73#[derive(Debug, Clone)]
74pub enum ConfigLoadError {
75    /// I/O error (file not found, network error).
76    Io(String),
77    /// Parse error (invalid YAML/JSON).
78    Parse(String),
79}
80
81impl std::fmt::Display for ConfigLoadError {
82    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
83        match self {
84            Self::Io(msg) => write!(f, "Config I/O error: {}", msg),
85            Self::Parse(msg) => write!(f, "Config parse error: {}", msg),
86        }
87    }
88}
89
90impl std::error::Error for ConfigLoadError {}
91
92#[cfg(test)]
93#[allow(clippy::unwrap_used)]
94mod tests {
95    use super::*;
96
97    #[tokio::test]
98    async fn test_load_default_config() {
99        let config = load_config(&ConfigSource::Default).await.unwrap();
100        assert!(!config.companies.is_empty());
101    }
102
103    #[tokio::test]
104    async fn test_load_inline_config() {
105        let yaml = r#"
106global:
107  industry: manufacturing
108  start_date: "2024-01-01"
109  period_months: 1
110  seed: 42
111  parallel: false
112  group_currency: USD
113  worker_threads: 1
114  memory_limit_mb: 512
115companies:
116  - code: TEST
117    name: Test Company
118    currency: USD
119    country: US
120    annual_transaction_volume: ten_k
121    volume_weight: 1.0
122    fiscal_year_variant: K4
123chart_of_accounts:
124  complexity: small
125output:
126  output_directory: ./output
127"#;
128        let source = ConfigSource::Inline {
129            content: yaml.to_string(),
130        };
131        let config = load_config(&source).await.unwrap();
132        assert_eq!(config.companies[0].code, "TEST");
133    }
134
135    #[tokio::test]
136    async fn test_load_missing_file() {
137        let source = ConfigSource::File {
138            path: PathBuf::from("/nonexistent/config.yaml"),
139        };
140        assert!(load_config(&source).await.is_err());
141    }
142
143    #[tokio::test]
144    async fn test_load_invalid_yaml() {
145        let source = ConfigSource::Inline {
146            content: "{{invalid yaml:".to_string(),
147        };
148        assert!(load_config(&source).await.is_err());
149    }
150
151    #[tokio::test]
152    async fn test_reload_config() {
153        let initial = crate::grpc::service::default_generator_config();
154        let config_lock = Arc::new(RwLock::new(initial));
155
156        reload_config(&ConfigSource::Default, &config_lock)
157            .await
158            .unwrap();
159
160        let config = config_lock.read().await;
161        assert!(!config.companies.is_empty());
162    }
163}
datasynth_server/config_loader.rs

datasynth_server/
config_loader.rs
