add mysql2postgres

src/exchange_rate.rs

@@ -0,0 +1,48 @@
+//! Exchange rate conversion via apilayer.com.
+//! Port of `server/pkg/exchangeRate/exchangeRate.go`.
+
+use serde::Deserialize;
+
+const API_BASE: &str = "https://api.apilayer.com";
+
+#[derive(Debug, Deserialize)]
+struct ConvertResponse {
+    success: bool,
+    result: Option<f64>,
+}
+
+/// Convert `amount` from currency `from` to currency `to`.
+///
+/// - `access_key` — API key from apilayer.com (configured in `Config.Currency.AccessKey`)
+///
+/// Returns the converted amount, or an error if the request fails or the API
+/// reports failure.
+pub async fn convert(
+    from: &str,
+    to: &str,
+    amount: f64,
+    access_key: &str,
+) -> anyhow::Result<f64> {
+    let client = reqwest::Client::builder()
+        .timeout(std::time::Duration::from_secs(5))
+        .build()?;
+
+    let resp: ConvertResponse = client
+        .get(format!("{API_BASE}/currency_data/convert"))
+        .header("apikey", access_key)
+        .query(&[
+            ("from", from),
+            ("to", to),
+            ("amount", &amount.to_string()),
+        ])
+        .send()
+        .await?
+        .json()
+        .await?;
+
+    if !resp.success {
+        anyhow::bail!("exchange rate API returned failure for {from}→{to}");
+    }
+    resp.result
+        .ok_or_else(|| anyhow::anyhow!("exchange rate API returned no result"))
+}