begin header holder implementation with lazy parser by getters, add request::Mode, add common header_bytes helper

src/client/connection/response/success/default.rs

@@ -0,0 +1,27 @@
+pub mod error;
+pub mod header;
+
+pub use error::Error;
+pub use header::Header;
+
+pub const CODE: &[u8] = b"20";
+
+pub struct Default {
+    pub header: Header,
+    pub content: Option<Vec<u8>>,
+}
+
+impl Default {
+    // Constructors
+
+    pub fn parse(buffer: &[u8]) -> Result<Self, Error> {
+        if !buffer.starts_with(CODE) {
+            return Err(Error::Code);
+        }
+        let header = Header::parse(buffer).map_err(|e| Error::Header(e))?;
+        Ok(Self {
+            content: buffer.get(header.len() + 1..).map(|v| v.to_vec()),
+            header,
+        })
+    }
+}