Add add/remove_path_prefix fields to domain settings

src/domain/manager.rs

@@ -252,7 +252,12 @@ impl Manager for ManagerImpl {
             return Err(unexpected::Error::from("origin is proxy, can't serve file").into());
         }
 
-        let f = self.origin_store.get_file(&settings.origin_descr, path)?;
+        let path = settings.process_path(path);
+
+        let f = self
+            .origin_store
+            .get_file(&settings.origin_descr, path.as_ref())?;
+
         Ok(f)
     }
 

src/domain/settings.rs

@@ -1,6 +1,8 @@
 use crate::error::unexpected::{self, Mappable};
 use crate::origin;
 
+use std::borrow;
+
 use hex::ToHex;
 use serde::{Deserialize, Serialize};
 use sha2::{Digest, Sha256};
@@ -11,6 +13,9 @@ use sha2::{Digest, Sha256};
 pub struct Settings {
     #[serde(flatten)]
     pub origin_descr: origin::Descr,
+
+    pub remove_path_prefix: Option<String>,
+    pub add_path_prefix: Option<String>,
 }
 
 impl Settings {
@@ -19,4 +24,104 @@ impl Settings {
         serde_json::to_writer(&mut h, self).or_unexpected()?;
         Ok(h.finalize().encode_hex::<String>())
     }
+
+    fn remove_path_prefix<'path, 'prefix>(
+        path: borrow::Cow<'path, str>,
+        prefix: &'prefix str,
+    ) -> borrow::Cow<'path, str> {
+        if prefix.len() == 0 {
+            return path;
+        }
+
+        let mut prefix = prefix.trim_end_matches('/');
+        prefix = prefix.trim_start_matches('/');
+
+        let mut stripped_path = path.trim_start_matches('/');
+
+        if !stripped_path.starts_with(prefix) {
+            return path;
+        }
+
+        stripped_path = stripped_path.strip_prefix(prefix).unwrap();
+        if stripped_path.len() == 0 {
+            return borrow::Cow::Borrowed("/");
+        }
+
+        borrow::Cow::Owned(stripped_path.to_string())
+    }
+
+    fn add_path_prefix<'path, 'prefix>(
+        path: borrow::Cow<'path, str>,
+        prefix: &'prefix str,
+    ) -> borrow::Cow<'path, str> {
+        if prefix.len() == 0 {
+            return path;
+        }
+
+        let mut prefix = prefix.trim_end_matches('/');
+        prefix = prefix.trim_start_matches('/');
+
+        let mut prefixed_path = String::with_capacity(1 + prefix.len() + path.len());
+
+        prefixed_path.push('/');
+        prefixed_path.push_str(prefix);
+        prefixed_path.push_str(path.as_ref());
+
+        borrow::Cow::Owned(prefixed_path)
+    }
+
+    pub fn process_path<'a>(&self, path: &'a str) -> borrow::Cow<'a, str> {
+        let mut path = borrow::Cow::Borrowed(path);
+
+        if let Some(ref prefix) = self.remove_path_prefix {
+            path = Self::remove_path_prefix(path, prefix);
+        }
+
+        if let Some(ref prefix) = self.add_path_prefix {
+            path = Self::add_path_prefix(path, prefix);
+        }
+
+        path
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::borrow;
+
+    #[test]
+    fn remove_path_prefix() {
+        let assert_remove = |want: &str, path: &str, prefix: &str| {
+            assert_eq!(
+                want,
+                Settings::remove_path_prefix(borrow::Cow::Borrowed(path), prefix).as_ref(),
+            )
+        };
+
+        assert_remove("/bar", "/foo/bar", "/foo");
+        assert_remove("/foo/bar", "/foo/bar", "/baz");
+        assert_remove("/bar", "/foo/bar", "/foo/");
+        assert_remove("/bar", "/foo/bar", "/foo///");
+        assert_remove("/", "/", "/");
+        assert_remove("/", "/foo/bar/", "/foo/bar");
+        assert_remove("/", "/foo/bar", "/foo/bar");
+        assert_remove("/", "/foo/bar", "/foo/bar///");
+        assert_remove("/bar", "/bar", "");
+    }
+
+    #[test]
+    fn add_path_prefix() {
+        let assert_add = |want: &str, path: &str, prefix: &str| {
+            assert_eq!(
+                want,
+                Settings::add_path_prefix(borrow::Cow::Borrowed(path), prefix).as_ref(),
+            )
+        };
+
+        assert_add("/foo/bar", "/bar", "/foo");
+        assert_add("/foo/", "/", "/foo");
+        assert_add("/foo/", "/", "/foo///");
+        assert_add("/bar", "/bar", "");
+    }
 }

src/domain/store.rs

@@ -181,6 +181,8 @@ mod tests {
                 url: "bar".to_string(),
                 branch_name: "baz".to_string(),
             },
+            remove_path_prefix: None,
+            add_path_prefix: None,
         };
 
         assert!(matches!(
@@ -203,6 +205,8 @@ mod tests {
                 url: "BAR".to_string(),
                 branch_name: "BAZ".to_string(),
             },
+            remove_path_prefix: None,
+            add_path_prefix: None,
         };
 
         store.set(&domain, &new_settings).expect("set");

src/origin/proxy.rs

@@ -30,7 +30,7 @@ pub async fn serve_http_request(
     mut req: hyper::Request<hyper::Body>,
     req_is_https: bool,
 ) -> unexpected::Result<hyper::Response<hyper::Body>> {
-    let (proxy_url, request_http_headers) = if let origin::Descr::Proxy {
+    let (url, request_http_headers) = if let origin::Descr::Proxy {
         ref url,
         ref request_http_headers,
     } = settings.origin_descr
@@ -67,12 +67,12 @@ pub async fn serve_http_request(
             .insert("x-forwarded-proto", HeaderValue::from_static("https"));
     }
 
-    match hyper_reverse_proxy::call(client_ip, proxy_url, req).await {
+    match hyper_reverse_proxy::call(client_ip, url, req).await {
         Ok(res) => Ok(res),
         // ProxyError doesn't actually implement Error :facepalm: so we have to format the error
         // manually
         Err(e) => Err(unexpected::Error::from(
-            format!("error while proxying to {proxy_url}: {e:?}").as_str(),
+            format!("error while proxying to {url}: {e:?}").as_str(),
         )),
     }
 }

src/service/http.rs

@@ -54,7 +54,7 @@ struct BasePresenter<'a, T> {
 }
 
 #[derive(Deserialize)]
-struct DomainGetArgs {
+struct DomainArgs {
     domain: domain::Name,
 }
 
@@ -246,7 +246,7 @@ impl<'svc> Service {
         }
     }
 
-    fn domain_get(&self, args: DomainGetArgs) -> Response<Body> {
+    fn domain(&self, args: DomainArgs) -> Response<Body> {
         #[derive(Serialize)]
         struct Data {
             domain: domain::Name,
@@ -485,10 +485,8 @@ impl<'svc> Service {
                 self.render_page("/index.html", ())
             }
             (form_method, "/domain.html") if form_method == config_form_method => {
-                self.with_query_req(&req, body, |args: DomainGetArgs| async {
+                self.with_query_req(&req, body, |args: DomainArgs| async { self.domain(args) })
-                    self.domain_get(args)
+                    .await
-                })
-                .await
             }
             (form_method, "/domain_init.html") if form_method == config_form_method => {
                 self.with_query_req(&req, body, |args: DomainInitArgs| async {

src/service/http/tpl/domain.html

@@ -49,6 +49,31 @@ automatically updated too!</p>
     </p>
   </fieldset>
 
+  <fieldset>
+    <legend>Advanced Settings</legend>
+    <p>
+    <label>
+    Prefix to remove from URL paths:
+    <input name="domain_setting_remove_path_prefix"
+           type="text"
+           placeholder="/foo/bar"
+           value="{{ data.settings.remove_path_prefix }}"
+           required />
+    </label>
+    </p>
+
+    <p>
+    <label>
+    Prefix to add to URL paths:
+    <input name="domain_setting_add_path_prefix"
+           type="text"
+           placeholder="/foo/bar"
+           value="{{ data.settings.add_path_prefix }}"
+           required />
+    </label>
+    </p>
+  </fieldset>
+
   <input type="submit" value="Next" />
 
 </form>

src/service/util.rs

@@ -1,10 +1,12 @@
 use std::convert::TryFrom;
 
 use serde::{Deserialize, Serialize};
+use serde_with::{serde_as, NoneAsEmptyString};
 
 use crate::{domain, error::unexpected, origin};
 
-#[derive(Serialize, Deserialize, Default)]
+#[serde_as]
+#[derive(Serialize, Deserialize, Default, Debug)]
 pub struct FlatDomainSettings {
     domain_setting_origin_descr_kind: String,
 
@@ -12,6 +14,14 @@ pub struct FlatDomainSettings {
     domain_setting_origin_descr_git_branch_name: Option<String>,
 
     domain_setting_origin_descr_proxy_url: Option<String>,
+
+    #[serde(default)]
+    #[serde_as(as = "NoneAsEmptyString")]
+    domain_setting_remove_path_prefix: Option<String>,
+
+    #[serde(default)]
+    #[serde_as(as = "NoneAsEmptyString")]
+    domain_setting_add_path_prefix: Option<String>,
 }
 
 impl TryFrom<FlatDomainSettings> for domain::Settings {
@@ -31,7 +41,11 @@ impl TryFrom<FlatDomainSettings> for domain::Settings {
             _ => Err("invalid domain_setting_origin_descr_kind".to_string()),
         }?;
 
-        Ok(Self { origin_descr })
+        Ok(Self {
+            origin_descr,
+            remove_path_prefix: v.domain_setting_remove_path_prefix,
+            add_path_prefix: v.domain_setting_add_path_prefix,
+        })
     }
 }
 
@@ -54,6 +68,9 @@ impl TryFrom<domain::Settings> for FlatDomainSettings {
             }
         }
 
+        res.domain_setting_remove_path_prefix = v.remove_path_prefix;
+        res.domain_setting_add_path_prefix = v.add_path_prefix;
+
         Ok(res)
     }
 }