add fn to send gzip encoded result

Cargo.toml

@@ -12,4 +12,5 @@ serde_json = "1.0"
 toml = "0.5"
 chrono = {version = "0.4", features = ["serde"]}
 minify = "1.2"
-handlebars_sprig = { version = "0.1.0" }
+handlebars_sprig = { version = "0.1.0" }
+flate2 = "1.0.22"

src/response.rs

@@ -1,3 +1,7 @@
+use flate2::write::GzEncoder;
+use flate2::Compression;
+use std::io::{self, Write};
+
 pub fn not_found(route: String, body: String) {
     eprintln!("Not Found: {}", route);
     println!("Content-Type: text/html; charset=utf-8");
@@ -27,3 +31,23 @@ pub fn send_redirect(route: String, location: String, status: String) {
     eprintln!("redirected {} to {} (Code: {})", route, &location, &status);
     println!("Status: {}\nLocation: {}\n", status, location)
 }
+
+pub fn send_gzip_result(
+    route: String,
+    body: String,
+    content_type: String,
+    status_opt: Option<String>,
+) {
+    eprintln!("responded: {}", route);
+
+    // Intentionally do not override the Wagi default behavior with a default Bartholomew message.
+    if let Some(status) = status_opt {
+        println!("Status: {}", status);
+    }
+    println!("Content-Encoding: {}", "gzip");
+    println!("Content-Type: {}\n", content_type);
+
+    let mut e = GzEncoder::new(Vec::new(), Compression::default());
+    e.write_all(body.as_bytes()).unwrap();
+    io::stdout().write_all(&e.finish().unwrap()).unwrap();
+}