server: refactor server logic into supervisor + session handler

This commit is contained in:
2025-11-26 15:51:54 +09:00
parent f5ff50365f
commit 20331a4429
9 changed files with 397 additions and 214 deletions

View File

@@ -0,0 +1,224 @@
use std::collections::BTreeSet;
use futures_util::{SinkExt, StreamExt};
use indoc::concatdoc;
use tokio::net::UnixStream;
use sqlx::MySqlConnection;
use sqlx::prelude::*;
use crate::core::protocol::SetPasswordError;
use crate::server::sql::database_operations::list_databases;
use crate::{
core::{
common::UnixUser,
protocol::{
Request, Response, ServerToClientMessageStream, create_server_to_client_message_stream,
},
},
server::{
config::{ServerConfig, create_mysql_connection_from_config},
sql::{
database_operations::{create_databases, drop_databases, list_all_databases_for_user},
database_privilege_operations::{
apply_privilege_diffs, get_all_database_privileges, get_databases_privilege_data,
},
user_operations::{
create_database_users, drop_database_users, list_all_database_users_for_unix_user,
list_database_users, lock_database_users, set_password_for_database_user,
unlock_database_users,
},
},
},
};
// TODO: don't use database connection unless necessary.
pub async fn session_handler(
socket: UnixStream,
unix_user: &UnixUser,
config: &ServerConfig,
) -> anyhow::Result<()> {
let mut message_stream = create_server_to_client_message_stream(socket);
log::debug!("Opening connection to database");
let mut db_connection = match create_mysql_connection_from_config(&config.mysql).await {
Ok(connection) => connection,
Err(err) => {
message_stream
.send(Response::Error(
(concatdoc! {
"Server failed to connect to database\n",
"Please check the server logs or contact the system administrators"
})
.to_string(),
))
.await?;
message_stream.flush().await?;
return Err(err);
}
};
log::debug!("Verifying that database connection is valid");
if let Err(e) = db_connection.ping().await {
log::error!("Failed to ping database: {}", e);
message_stream
.send(Response::Error(
(concatdoc! {
"Server failed to connect to database\n",
"Please check the server logs or contact the system administrators"
})
.to_string(),
))
.await?;
message_stream.flush().await?;
close_or_ignore_db_connection(db_connection).await;
return Err(e.into());
}
log::debug!("Successfully connected to database");
let result =
session_handler_with_db_connection(message_stream, unix_user, &mut db_connection).await;
close_or_ignore_db_connection(db_connection).await;
result
}
// TODO: ensure proper db_connection hygiene for functions that invoke
// this function
async fn session_handler_with_db_connection(
mut stream: ServerToClientMessageStream,
unix_user: &UnixUser,
db_connection: &mut MySqlConnection,
) -> anyhow::Result<()> {
stream.send(Response::Ready).await?;
loop {
// TODO: better error handling
let request = match stream.next().await {
Some(Ok(request)) => request,
Some(Err(e)) => return Err(e.into()),
None => {
log::warn!("Client disconnected without sending an exit message");
break;
}
};
// TODO: don't clone the request
let request_to_display = match &request {
Request::PasswdUser((db_user, _)) => {
Request::PasswdUser((db_user.to_owned(), "<REDACTED>".to_string()))
}
request => request.to_owned(),
};
log::info!("Received request: {:#?}", request_to_display);
let response = match request {
Request::CreateDatabases(databases_names) => {
let result = create_databases(databases_names, unix_user, db_connection).await;
Response::CreateDatabases(result)
}
Request::DropDatabases(databases_names) => {
let result = drop_databases(databases_names, unix_user, db_connection).await;
Response::DropDatabases(result)
}
Request::ListDatabases(database_names) => match database_names {
Some(database_names) => {
let result = list_databases(database_names, unix_user, db_connection).await;
Response::ListDatabases(result)
}
None => {
let result = list_all_databases_for_user(unix_user, db_connection).await;
Response::ListAllDatabases(result)
}
},
Request::ListPrivileges(database_names) => match database_names {
Some(database_names) => {
let privilege_data =
get_databases_privilege_data(database_names, unix_user, db_connection)
.await;
Response::ListPrivileges(privilege_data)
}
None => {
let privilege_data =
get_all_database_privileges(unix_user, db_connection).await;
Response::ListAllPrivileges(privilege_data)
}
},
Request::ModifyPrivileges(database_privilege_diffs) => {
let result = apply_privilege_diffs(
BTreeSet::from_iter(database_privilege_diffs),
unix_user,
db_connection,
)
.await;
Response::ModifyPrivileges(result)
}
Request::CreateUsers(db_users) => {
let result = create_database_users(db_users, unix_user, db_connection).await;
Response::CreateUsers(result)
}
Request::DropUsers(db_users) => {
let result = drop_database_users(db_users, unix_user, db_connection).await;
Response::DropUsers(result)
}
Request::PasswdUser((db_user, password)) => {
let result =
set_password_for_database_user(&db_user, &password, unix_user, db_connection)
.await;
Response::SetUserPassword(result)
}
Request::ListUsers(db_users) => match db_users {
Some(db_users) => {
let result = list_database_users(db_users, unix_user, db_connection).await;
Response::ListUsers(result)
}
None => {
let result =
list_all_database_users_for_unix_user(unix_user, db_connection).await;
Response::ListAllUsers(result)
}
},
Request::LockUsers(db_users) => {
let result = lock_database_users(db_users, unix_user, db_connection).await;
Response::LockUsers(result)
}
Request::UnlockUsers(db_users) => {
let result = unlock_database_users(db_users, unix_user, db_connection).await;
Response::UnlockUsers(result)
}
Request::Exit => {
break;
}
};
// TODO: don't clone the response
let response_to_display = match &response {
Response::SetUserPassword(Err(SetPasswordError::MySqlError(_))) => {
Response::SetUserPassword(Err(SetPasswordError::MySqlError(
"<REDACTED>".to_string(),
)))
}
response => response.to_owned(),
};
log::info!("Response: {:#?}", response_to_display);
stream.send(response).await?;
stream.flush().await?;
log::debug!("Successfully processed request");
}
Ok(())
}
async fn close_or_ignore_db_connection(db_connection: MySqlConnection) {
if let Err(e) = db_connection.close().await {
log::error!("Failed to close database connection: {}", e);
log::error!("{}", e);
log::error!("Ignoring...");
}
}