feat: add query string parser

Cargo.lock

@@ -1362,6 +1362,7 @@ dependencies = [
  "clap",
  "futures-core",
  "linked-hash-map",
+ "percent-encoding",
  "reqwest",
  "rust_util",
  "serde",

Cargo.toml

@@ -19,3 +19,4 @@ actix-rt = "1"
 bytes = "0.5"
 futures-core = "0.3"
 linked-hash-map = "0.5"
+percent-encoding = "2.1"

src/main.rs

@@ -36,11 +36,22 @@ impl futures_core::Stream for ProxyStream {
 }
 
 async fn get_file(req: HttpRequest) -> HttpResponse {
-    println!("{:?}", req);
     let query_string = req.query_string();
-    println!("Q: {}", query_string);
-    // TODO parse url
-    let resp = reqwest::get("http://example.com/").await.unwrap();
+    let parsed_query_string = parse_query_string(query_string);
+    information!("Parsed query string: {:?}", parsed_query_string);
+
+    let url = match parsed_query_string.get("url") {
+        None => None,
+        Some(v) => v.iter().next().clone(),
+    };
+    let url = match url {
+        Some(u) => u, None => {
+            return HttpResponse::BadRequest().content_type("text/plain").body("No url!");
+        },
+    };
+
+    let resp = reqwest::get(url.as_str()).await.unwrap();
+    // TODO ...
     HttpResponse::Ok()
         .content_type("text/plain")
         .streaming(ProxyStream{ inner: Box::new(resp.bytes_stream()) })
@@ -71,7 +82,38 @@ async fn main() -> std::io::Result<()> {
 }
 
 fn parse_query_string(query_string: &str) -> LinkedHashMap<String, Vec<String>> {
-    let map = LinkedHashMap::new();
-    // TODO ...
+    let mut map = LinkedHashMap::new();
+    query_string.split('&').for_each(|kv| {
+        let mut meet_equal = false;
+        let mut k = String::new();
+        let mut v = String::new();
+        kv.chars().for_each(|c| {
+            if meet_equal {
+                v.push(c);
+            } else if c == '=' {
+                meet_equal = true;
+            } else {
+                k.push(c);
+            }
+        });
+        let k = percent_encoding::percent_decode_str(&k).decode_utf8_lossy().into_owned();
+        let v = percent_encoding::percent_decode_str(&v).decode_utf8_lossy().into_owned();
+        match map.get_mut(&k) {
+            None => { map.insert(k, vec![v]); },
+            Some(values) => { values.push(v); },
+        }
+    });
     map
 }
+
+#[test]
+fn test_parse_query_string() {
+    let mut e = LinkedHashMap::new();
+    e.insert("a".to_string(), vec!["b".to_string()]);
+    let m = parse_query_string("a=b");
+    assert_eq!(e, m);
+    let mut e = LinkedHashMap::new();
+    e.insert("a".to_string(), vec!["b".to_string(), "c".to_string()]);
+    let m = parse_query_string("a=b&a=c");
+    assert_eq!(e, m);
+}