feat: Add a Builder struct and use it in from_[head|tail]_response

src/error.rs

@@ -30,6 +30,10 @@ pub enum AsyncHttpRangeReaderError {
     /// Memory mapping the file failed
     #[error("memory mapping the file failed")]
     MemoryMapError(#[source] Arc<std::io::Error>),
+
+    /// Error building the reader
+    #[error("error building the reader: {0}")]
+    BuilderError(#[source] Arc<AsyncHttpRangeReaderBuilderError>),
 }
 
 impl From<std::io::Error> for AsyncHttpRangeReaderError {
@@ -49,3 +53,25 @@ impl From<reqwest::Error> for AsyncHttpRangeReaderError {
         AsyncHttpRangeReaderError::TransportError(Arc::new(err.into()))
     }
 }
+
+impl From<AsyncHttpRangeReaderBuilderError> for AsyncHttpRangeReaderError {
+    fn from(err: AsyncHttpRangeReaderBuilderError) -> Self {
+        AsyncHttpRangeReaderError::BuilderError(Arc::new(err))
+    }
+}
+
+/// Error type used for [`crate::AsyncHttpRangeReaderBuilder`]
+#[derive(Clone, Debug, thiserror::Error)]
+pub enum AsyncHttpRangeReaderBuilderError {
+    /// Required field 'content_length' is zero
+    #[error("required field 'content_length' is zero")]
+    InvalidContentLength,
+
+    /// Required field 'url' is missing
+    #[error("required field 'url' is missing")]
+    MissingUrl,
+
+    /// Memory mapping the file failed
+    #[error("memory mapping the file failed")]
+    MemoryMapError(#[source] Arc<std::io::Error>),
+}