fix: change target's type in fee estimate map

Author: vladimirfomene

src/async.rs

@@ -380,7 +380,7 @@ impl AsyncClient {
 
     /// Get an map where the key is the confirmation target (in number of blocks)
     /// and the value is the estimated feerate (in sat/vB).
-    pub async fn get_fee_estimates(&self) -> Result<HashMap<String, f64>, Error> {
+    pub async fn get_fee_estimates(&self) -> Result<HashMap<u16, f64>, Error> {
         let resp = self
             .client
             .get(&format!("{}/fee-estimates", self.url,))
@@ -393,7 +393,7 @@ impl AsyncClient {
                 message: resp.text().await?,
             })
         } else {
-            Ok(resp.json::<HashMap<String, f64>>().await?)
+            Ok(resp.json::<HashMap<u16, f64>>().await?)
         }
     }
 

src/blocking.rs

@@ -343,15 +343,15 @@ impl BlockingClient {
 
     /// Get an map where the key is the confirmation target (in number of blocks)
     /// and the value is the estimated feerate (in sat/vB).
-    pub fn get_fee_estimates(&self) -> Result<HashMap<String, f64>, Error> {
+    pub fn get_fee_estimates(&self) -> Result<HashMap<u16, f64>, Error> {
         let resp = self
             .agent
             .get(&format!("{}/fee-estimates", self.url,))
             .call();
 
         let map = match resp {
             Ok(resp) => {
-                let map: HashMap<String, f64> = resp.into_json()?;
+                let map: HashMap<u16, f64> = resp.into_json()?;
                 Ok(map)
             }
             Err(ureq::Error::Status(code, resp)) => Err(Error::HttpResponse {