Add validator

src/main.rs

@@ -17,6 +17,7 @@ use maud::{html, Escaper, Markup, PreEscaped, DOCTYPE};
 use serde::{Deserialize, Serialize};
 use store::Store;
 use tokio::net::TcpListener;
+use validator::{Validate, ValidationError};
 
 mod common;
 mod store;
@@ -146,35 +147,38 @@ async fn topic(Path(name): Path<String>, State(state): State<MainState>) -> impl
     )
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize, Validate)]
 struct PostContent {
+    #[validate(length(min = 1, max = 32), custom(function = "validate_topic"))]
     topic: String,
+    #[validate(length(min = 10, max = 10_000))]
     content: String,
+    #[validate(length(min = 2, max = 32))]
     author: String,
 }
 
-async fn post(
-    State(state): State<MainState>,
-    Form(PostContent {
+fn validate_topic(topic: &str) -> Result<(), ValidationError> {
+    if topic.starts_with('_') || topic.ends_with('_') {
+        return Err(ValidationError::new("Bad topic format."));
+    }
+    Ok(())
+}
+
+async fn post(State(state): State<MainState>, Form(post_content): Form<PostContent>) -> Response {
+    let mut store = state.store.write().unwrap();
+    let date = Utc::now().format("%d/%m/%Y");
+
+    if post_content.validate().is_err() {
+        return (StatusCode::BAD_REQUEST, "Bad input.").into_response();
+    }
+
+    let PostContent {
         topic,
         content,
         author,
-    }): Form<PostContent>,
-) -> Response {
-    let mut store = state.store.write().unwrap();
-    let date = Utc::now().format("%d/%m/%Y");
-    let topic = sanithize_identifier(topic.trim());
-    let content = content.trim();
+    } = post_content;
 
-    if content.len() < 10 || content.len() > 10_000 {
-        return (StatusCode::BAD_REQUEST, "Bad content.").into_response();
-    }
-    if author.len() > 2 || author.len() > 32 {
-        return (StatusCode::BAD_REQUEST, "Bad author.").into_response();
-    }
-    if topic.len() > 32 || topic.is_empty() || topic.starts_with('_') || topic.ends_with('_') {
-        return (StatusCode::BAD_REQUEST, "Bad topic.").into_response();
-    }
+    let topic = sanithize_identifier(&topic);
 
     let content = format!("{content}\n\t~{author}, {date}");
     store.insert(&topic, content).unwrap();