added creating CompanyInfo mapping

src/config.rs

@@ -1,14 +1,23 @@
-// src/config.rs
-#[derive(Debug, Clone)]
+use anyhow::{Context, Result};
+use chrono::{self, Duration};
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Config {
     // Economic calendar start (usually the earliest available on finanzen.net)
     pub economic_start_date: String,     // e.g. "2007-02-13"
-
     // Corporate earnings & price history start
     pub corporate_start_date: String,    // e.g. "2000-01-01" or "2010-01-01"
-
     // How far into the future we scrape economic events
     pub economic_lookahead_months: u32,  // default: 3
+    /// Maximum number of parallel scraping tasks (default: 10).
+    /// This limits concurrency to protect system load and prevent website spamming.
+    #[serde(default = "default_max_parallel")]
+    pub max_parallel_tasks: usize,
+}
+
+fn default_max_parallel() -> usize {
+    10
 }
 
 impl Default for Config {
@@ -17,11 +26,52 @@ impl Default for Config {
             economic_start_date: "2007-02-13".to_string(),
             corporate_start_date: "2010-01-01".to_string(),
             economic_lookahead_months: 3,
+            max_parallel_tasks: default_max_parallel(),
         }
     }
 }
 
 impl Config {
+    /// Loads the configuration from environment variables using dotenvy.
+    ///
+    /// This function loads a `.env` file if present (via `dotenvy::dotenv()`),
+    /// then retrieves each configuration value from environment variables.
+    /// If a variable is missing, it falls back to the default value.
+    /// Variable names are uppercase with underscores (e.g., ECONOMIC_START_DATE).
+    ///
+    /// # Returns
+    /// The loaded Config on success.
+    ///
+    /// # Errors
+    /// Returns an error if parsing fails (e.g., invalid integer for lookahead months).
+    pub fn load() -> Result<Self> {
+        // Load .env file if it exists; ignore if not found (dotenvy::dotenv returns Ok if no file)
+        let _ = dotenvy::dotenv().context("Failed to load .env file (optional)")?;
+
+        let economic_start_date = dotenvy::var("ECONOMIC_START_DATE")
+            .unwrap_or_else(|_| "2007-02-13".to_string());
+
+        let corporate_start_date = dotenvy::var("CORPORATE_START_DATE")
+            .unwrap_or_else(|_| "2010-01-01".to_string());
+
+        let economic_lookahead_months: u32 = dotenvy::var("ECONOMIC_LOOKAHEAD_MONTHS")
+            .unwrap_or_else(|_| "3".to_string())
+            .parse()
+            .context("Failed to parse ECONOMIC_LOOKAHEAD_MONTHS as u32")?;
+
+        let max_parallel_tasks: usize = dotenvy::var("MAX_PARALLEL_TASKS")
+            .unwrap_or_else(|_| "10".to_string())
+            .parse()
+            .context("Failed to parse MAX_PARALLEL_TASKS as usize")?;
+
+        Ok(Self {
+            economic_start_date,
+            corporate_start_date,
+            economic_lookahead_months,
+            max_parallel_tasks,
+        })
+    }
+
     pub fn target_end_date(&self) -> String {
         let now = chrono::Local::now().naive_local().date();
         let future = now + chrono::Duration::days(30 * self.economic_lookahead_months as i64);