persist command

src/commands/mod.rs

@@ -2,6 +2,7 @@ mod delete;
 mod expire;
 mod get;
 mod has;
+mod persist;
 mod set;
 mod ttl;
 
@@ -12,6 +13,7 @@ use delete::Delete;
 use expire::Expire;
 use get::Get;
 use has::Has;
+use persist::Persist;
 use set::Set;
 use ttl::Ttl;
 
@@ -25,6 +27,7 @@ pub enum Command {
     Has(Has),
     Ttl(Ttl),
     Expire(Expire),
+    Persist(Persist),
 }
 
 impl Command {
@@ -36,6 +39,7 @@ impl Command {
             Command::Has(has) => has.execute(db, connection).await,
             Command::Ttl(ttl) => ttl.execute(db, connection).await,
             Command::Expire(expire) => expire.execute(db, connection).await,
+            Command::Persist(persist) => persist.execute(db, connection).await,
         }
     }
 
@@ -61,6 +65,7 @@ impl Command {
             "has" => Self::Has(Has::parse(bytes)?),
             "ttl" => Self::Ttl(Ttl::parse(bytes)?),
             "expire" => Self::Expire(Expire::parse(bytes)?),
+            "persist" => Self::Persist(Persist::parse(bytes)?),
             _ => return Err(AppError::UnknownCommand(command_name)),
         };
 

src/commands/persist.rs

@@ -0,0 +1,34 @@
+use std::io::Cursor;
+
+use bytes::{Buf as _, Bytes};
+
+use crate::{Result, connection::Connection, database::Database, errors::AppError};
+
+#[derive(Debug, Clone)]
+pub struct Persist {
+    key: String,
+}
+
+impl Persist {
+    pub async fn execute(self, db: &Database, connection: &mut Connection) -> Result<()> {
+        let value = db.persist(&self.key).await?;
+
+        connection
+            .write(Bytes::from_static(if value { &[1] } else { &[0] }))
+            .await?;
+
+        Ok(())
+    }
+
+    pub fn parse(bytes: &mut Cursor<&[u8]>) -> Result<Self> {
+        let key_length = bytes.try_get_u16()? as usize;
+
+        if bytes.remaining() < key_length {
+            return Err(AppError::IncompleteCommandBuffer);
+        }
+
+        let key = String::from_utf8(bytes.copy_to_bytes(key_length).to_vec())?;
+
+        Ok(Self { key })
+    }
+}