refactor(proto): replace anyhow with thiserror in handshake

proto/src/handshake/errors.rs

@@ -0,0 +1,21 @@
+use thiserror::Error;
+use tokio::io;
+use crate::message::errors::ProtoDeserializeError;
+use crate::reader::errors::{ProtoConsumeError, ProtoPeekError};
+use crate::writer::errors::ProtoWriteError;
+
+#[derive(Debug, Error)]
+pub enum ServerHandshakeError {
+    #[error("startup message not found")]
+    MissingStartupMessage,
+    #[error("reading from socket failed")]
+    Io(#[from] io::Error),
+    #[error("deserialization of inner data failed")]
+    Deserialize(#[from] ProtoDeserializeError),
+    #[error("peeking special message failed")]
+    Peek(#[from] ProtoPeekError),
+    #[error("consuming special message failed")]
+    Consume(#[from] ProtoConsumeError),
+    #[error("writing message to socket failed")]
+    Write(#[from] ProtoWriteError),
+}

proto/src/handshake/mod.rs

@@ -1 +1,2 @@
 pub mod server;
+pub mod errors;

proto/src/handshake/server.rs

@@ -1,3 +1,4 @@
+use crate::handshake::errors::ServerHandshakeError;
 use crate::message::backend::{
     AuthenticationOkData, BackendKeyDataData, BackendMessage, ParameterStatusData,
     ReadyForQueryData,
@@ -13,7 +14,7 @@ pub async fn do_server_handshake(
     name: &str,
     process: i32,
     secret: i32,
-) -> anyhow::Result<StartupMessageData> {
+) -> Result<StartupMessageData, ServerHandshakeError> {
     match &reader.peek_special_message().await? {
         Some(msg @ SpecialMessage::SSLRequest) => {
             reader.consume_special_message(msg).await?;
@@ -31,7 +32,7 @@ pub async fn do_server_handshake(
             data.clone()
         }
         _ => {
-            return Err(anyhow::anyhow!("Expected Startup Message"));
+            return Err(ServerHandshakeError::MissingStartupMessage);
         }
     };