update path pattern matcher

src/backend.rs

@@ -1,8 +1,8 @@
-use crate::backend_opt::UpstreamOption;
-use crate::log::*;
+use crate::{backend_opt::UpstreamOption, log::*};
 use rand::Rng;
 use rustc_hash::{FxHashMap as HashMap, FxHashSet as HashSet};
 use std::{
+  borrow::Cow,
   fs::File,
   io::{self, BufReader, Cursor, Read},
   path::PathBuf,
@@ -15,6 +15,7 @@ use tokio_rustls::rustls::{Certificate, PrivateKey, ServerConfig};
 
 // server name (hostname or ip address) in ascii lower case
 pub type ServerNameLC = Vec<u8>;
+pub type PathNameLC = Vec<u8>;
 
 pub struct Backends {
   pub apps: HashMap<ServerNameLC, Backend>, // TODO: hyper::uriで抜いたhostで引っ掛ける。Stringでいいのか？
@@ -34,8 +35,42 @@ pub struct Backend {
 
 #[derive(Debug, Clone)]
 pub struct ReverseProxy {
-  pub default_upstream: Option<Upstream>,
-  pub upstream: HashMap<String, Upstream>,
+  pub upstream: HashMap<PathNameLC, Upstream>,
+}
+
+impl ReverseProxy {
+  pub fn get<'a>(&self, path_str: impl Into<Cow<'a, str>>) -> Option<&Upstream> {
+    // trie使ってlongest prefix match させてもいいけどルート記述は少ないと思われるので、
+    // コスト的にこの程度で十分
+    let path_lc = path_str.into().to_ascii_lowercase();
+    let path_bytes = path_lc.as_bytes();
+
+    let matched_upstream = self
+      .upstream
+      .iter()
+      .filter(|(route_bytes, _)| {
+        match path_bytes.starts_with(route_bytes) {
+          true => {
+            route_bytes.len() == 1 // route = '/', i.e., default
+            || match path_bytes.get(route_bytes.len()) {
+              None => true, // exact case
+              Some(p) => p == &b'/', // sub-path case
+            }
+          }
+          _ => false,
+        }
+      })
+      .max_by_key(|(route_bytes, _)| route_bytes.len());
+    if let Some((_path, u)) = matched_upstream {
+      debug!(
+        "Found upstream: {:?}",
+        String::from_utf8(_path.to_vec()).unwrap_or_else(|_| "<none>".to_string())
+      );
+      Some(u)
+    } else {
+      None
+    }
+  }
 }
 
 #[allow(dead_code)]

src/config/parse.rs

@@ -1,6 +1,6 @@
 use super::toml::{ConfigToml, ReverseProxyOption};
 use crate::{
-  backend::{Backend, ReverseProxy, Upstream},
+  backend::{Backend, PathNameLC, ReverseProxy, Upstream},
   backend_opt::UpstreamOption,
   constants::*,
   error::*,
@@ -169,8 +169,7 @@ pub fn parse_opts(globals: &mut Globals) -> Result<()> {
 }
 
 fn get_reverse_proxy(rp_settings: &[ReverseProxyOption]) -> Result<ReverseProxy> {
-  let mut upstream: HashMap<String, Upstream> = HashMap::default();
-  let mut default_upstream: Option<Upstream> = None;
+  let mut upstream: HashMap<PathNameLC, Upstream> = HashMap::default();
   rp_settings.iter().for_each(|rpo| {
     let elem = Upstream {
       uri: rpo.upstream.iter().map(|x| x.to_uri().unwrap()).collect(),
@@ -189,17 +188,17 @@ fn get_reverse_proxy(rp_settings: &[ReverseProxyOption]) -> Result<ReverseProxy>
     };
 
     if rpo.path.is_some() {
-      upstream.insert(rpo.path.as_ref().unwrap().to_owned(), elem);
+      upstream.insert(
+        rpo.path.as_ref().unwrap().as_bytes().to_ascii_lowercase(),
+        elem,
+      );
     } else {
-      default_upstream = Some(elem)
+      upstream.insert("/".as_bytes().to_ascii_lowercase(), elem);
     }
   });
   ensure!(
     rp_settings.iter().filter(|rpo| rpo.path.is_none()).count() < 2,
     "Multiple default reverse proxy setting"
   );
-  Ok(ReverseProxy {
-    default_upstream,
-    upstream,
-  })
+  Ok(ReverseProxy { upstream })
 }

src/msg_handler/handler.rs

@@ -54,14 +54,11 @@ where
       return secure_redirection(&backend.server_name, self.globals.https_port, &req);
     }
 
-    ///////////////////////
     // Find reverse proxy for given path and choose one of upstream host
-    // TODO: More flexible path matcher
+    // Longest prefix match
     let path = req.uri().path();
-    let upstream = if let Some(upstream) = backend.reverse_proxy.upstream.get(path) {
+    let upstream = if let Some(upstream) = backend.reverse_proxy.get(path) {
       upstream
-    } else if let Some(default_upstream) = &backend.reverse_proxy.default_upstream {
-      default_upstream
     } else {
       return http_error(StatusCode::NOT_FOUND);
     };
@@ -70,7 +67,6 @@ where
     } else {
       return http_error(StatusCode::INTERNAL_SERVER_ERROR);
     };
-    ///////////////////////
 
     // Upgrade in request header
     let upgrade_in_request = extract_upgrade(req.headers());