feat: #2 impl an HTTPResponse + update tests

src/handlers/mod.rs

@@ -1,3 +1,5 @@
 pub mod request;
+pub mod response;
 
 pub use request::handle_request;
+pub use response::HTTPResponse;

src/handlers/response.rs

@@ -0,0 +1,98 @@
+//! response handles the incoming request parsed `HTTPRequest`
+//! it will check if the `HTTPRequest` is valid and build an HTTPResponse corresponding to the HTTP
+//! message specs. see: https://developer.mozilla.org/en-US/docs/Web/HTTP/Messages
+//! NOTE: only few parts of the specification has been implemented
+
+use json;
+
+use crate::handlers::request::{HTTPRequest, HTTPVersion};
+
+enum HTTPStatusCode {
+    Http200,
+    Http400,
+    Http404,
+    Http500,
+}
+
+impl Into<String> for HTTPStatusCode {
+    fn into(self) -> String {
+        match self {
+            Self::Http200 => "200".to_string(),
+            Self::Http400 => "400".to_string(),
+            Self::Http404 => "404".to_string(),
+            Self::Http500 => "500".to_string(),
+        }
+    }
+}
+
+pub struct HTTPStatusLine {
+    version: HTTPVersion,
+    status_code: HTTPStatusCode,
+}
+
+impl Default for HTTPStatusLine {
+    fn default() -> HTTPStatusLine {
+        HTTPStatusLine {
+            version: HTTPVersion::Http1_1,
+            status_code: HTTPStatusCode::Http400,
+        }
+    }
+}
+
+impl Into<String> for HTTPStatusLine {
+    fn into(self) -> String {
+        let version: String = self.version.into();
+        let status_code: String = self.status_code.into();
+        format! {"{} {}", version, status_code}
+    }
+}
+
+pub struct HTTPResponse {
+    status_line: HTTPStatusLine,
+    body: json::JsonValue,
+}
+
+impl Default for HTTPResponse {
+    fn default() -> Self {
+        HTTPResponse {
+            status_line: HTTPStatusLine::default(),
+            body: json::parse(r#"{"error": "the incoming request is not valid"}"#).unwrap(),
+        }
+    }
+}
+
+impl From<HTTPRequest> for HTTPResponse {
+    fn from(request: HTTPRequest) -> Self {
+        let mut response = HTTPResponse::default();
+        if !request.is_valid() {
+            return response;
+        }
+
+        let body = json::parse(
+            r#"{"token": "header.payload.signature", "refresh": "header.payload.signature"}"#,
+        )
+        .unwrap();
+
+        response.status_line.version = request.start_line.version;
+        response.status_line.status_code = HTTPStatusCode::Http200;
+        response.body = body;
+
+        response
+    }
+}
+
+impl Into<String> for HTTPResponse {
+    fn into(self) -> String {
+        // move `self.body` into a new var
+        let b = self.body;
+        let body: String = json::stringify(b);
+
+        let status_line: String = self.status_line.into();
+        format!(
+            "{}\r\nContent-Type: application/json\r\nContent-Length: {}\r\n\r\n{}",
+            status_line,
+            body.len(),
+            body
+        )
+    }
+}