3 files changed, 107 insertions, 0 deletions

diff --git a/src/error/client.rs b/src/error/client.rs
new file mode 100644
index 0000000..980e3d2
--- /dev/null
+++ b/src/error/client.rs
@@ -0,0 +1,33 @@
+pub enum ClientError {
+    BadJsonBody(String),
+    BadAuthTokenHeader(String),
+    UserAlreadyExists { username: String },
+    InvalidPassword,
+    NotAuthorized,
+}
+
+impl ClientError {
+    pub fn kind(&self) -> String {
+        match self {
+            Self::BadJsonBody(..) => "BadJsonBody",
+            Self::BadAuthTokenHeader(..) => "BadAuthTokenHeader",
+            Self::UserAlreadyExists { .. } => "UserAlreadyExists",
+            Self::InvalidPassword => "InvalidPassword",
+            Self::NotAuthorized => "NotAuthorized",
+        }
+        .to_string()
+    }
+
+    pub fn into_message(self) -> String {
+        match self {
+            Self::BadJsonBody(msg) => msg,
+            Self::BadAuthTokenHeader(msg) => msg,
+            Self::UserAlreadyExists { username } => {
+                format!("user with username `{}` already exists", username)
+            }
+            Self::InvalidPassword => "password is invalid".to_string(),
+
+            Self::NotAuthorized => "user is not authorized".to_string(),
+        }
+    }
+}
diff --git a/src/error/mod.rs b/src/error/mod.rs
new file mode 100644
index 0000000..55d7250
--- /dev/null
+++ b/src/error/mod.rs
@@ -0,0 +1,50 @@
+mod client;
+mod server;
+
+pub use client::ClientError;
+pub use server::ServerError;
+
+use argon2::password_hash::Error as PasswordHashError;
+use axum::extract::rejection::JsonRejection;
+use axum_extra::typed_header::TypedHeaderRejection;
+use sea_orm::DbErr;
+
+pub enum ApiError {
+    Client(ClientError),
+    Server(ServerError),
+}
+
+impl From<ClientError> for ApiError {
+    fn from(value: ClientError) -> Self {
+        Self::Client(value)
+    }
+}
+impl From<ServerError> for ApiError {
+    fn from(value: ServerError) -> Self {
+        Self::Server(value)
+    }
+}
+
+impl From<JsonRejection> for ApiError {
+    fn from(value: JsonRejection) -> Self {
+        Self::Client(ClientError::BadJsonBody(value.body_text()))
+    }
+}
+
+impl From<TypedHeaderRejection> for ApiError {
+    fn from(value: TypedHeaderRejection) -> Self {
+        Self::Client(ClientError::BadAuthTokenHeader(value.to_string()))
+    }
+}
+
+impl From<DbErr> for ApiError {
+    fn from(value: DbErr) -> Self {
+        Self::Server(ServerError::Database(value.to_string()))
+    }
+}
+
+impl From<PasswordHashError> for ApiError {
+    fn from(value: PasswordHashError) -> Self {
+        Self::Server(ServerError::PasswordHash(value.to_string()))
+    }
+}
diff --git a/src/error/server.rs b/src/error/server.rs
new file mode 100644
index 0000000..e67714d
--- /dev/null
+++ b/src/error/server.rs
@@ -0,0 +1,24 @@
+pub enum ServerError {
+    Database(String),
+    PasswordHash(String),
+    Token(String),
+}
+
+impl ServerError {
+    pub fn kind(&self) -> String {
+        match self {
+            Self::Database(..) => "Database",
+            Self::PasswordHash(..) => "PasswordHash",
+            Self::Token(..) => "Token",
+        }
+        .to_string()
+    }
+
+    pub fn into_message(self) -> String {
+        match self {
+            Self::Database(msg) => msg,
+            Self::PasswordHash(msg) => msg,
+            Self::Token(msg) => msg,
+        }
+    }
+}