Sarthak | Adds KeyValue

Cargo.toml

@@ -6,3 +6,4 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+bytes = "1.6.1"

src/key_value.rs

@@ -0,0 +1,63 @@
+use std::io::{Error, Read};
+use std::mem;
+
+use bytes::{Buf, BufMut, BytesMut};
+
+const U16_SIZE: usize = mem::size_of::<u16>();
+
+pub(crate) struct KeyValue {
+    key: Vec<u8>,
+    value: Vec<u8>,
+}
+
+impl KeyValue {
+    pub fn new(key: Vec<u8>, value: Vec<u8>) -> KeyValue {
+        assert!(key.len() > 0);
+        assert!(value.len() > 0);
+        KeyValue {key, value}
+    }
+
+    pub(crate) fn encode(&self) -> BytesMut {
+        let mut buffer = BytesMut::new();
+        buffer.put_u16_le(self.key.len() as u16);
+        buffer.put_u16_le(self.value.len() as u16);
+        buffer.put_slice(&self.key);
+        buffer.put_slice(&self.value);
+        return buffer
+    }
+
+    pub(crate) fn decode_from(mut buffer: BytesMut) -> Result<KeyValue, Error> {
+        let key_length = buffer.get_u16_le();
+        let value_length = buffer.get_u16_le();
+
+        let mut buffer_reader = buffer.reader();
+
+        let mut key = Vec::with_capacity(key_length as usize);
+        key.resize(key_length as usize, 0);
+        buffer_reader.read_exact(&mut key)?;
+
+        let mut value = Vec::with_capacity(value_length as usize);
+        value.resize(value_length as usize, 0);
+        buffer_reader.read_exact(&mut value)?;
+
+        println!("Key {:?}", key);
+        println!("Value {:?}", value);
+
+        return Ok(KeyValue::new(key, value))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::key_value::KeyValue;
+
+    #[test]
+    fn encodes_and_decodes_key_value() {
+        let key_value = KeyValue::new(Vec::from(b"raft"), Vec::from(b"consensus"));
+        let encoded = key_value.encode();
+
+        let decoded = KeyValue::decode_from(encoded).expect("Failed to decode the key_value");
+        assert_eq!(b"raft", &decoded.key[..]);
+        assert_eq!(b"consensus", &decoded.value[..]);
+    }
+}

src/main.rs

@@ -1,4 +1,5 @@
 mod memory;
+pub mod key_value;
 
 fn main() {
     println!("Hello, world!");