New perm concept, reference, and adding routes.

src/database/guards/reference.rs

@@ -0,0 +1,52 @@
+use mongodb::bson::{doc, from_bson, Bson};
+use crate::util::result::{Error, Result};
+use serde::{Deserialize, Serialize};
+use crate::database::get_collection;
+use crate::database::entities::*;
+use rocket::request::FromParam;
+use rocket::http::RawStr;
+use validator::Validate;
+
+#[derive(Validate, Serialize, Deserialize)]
+pub struct Ref {
+    #[validate(length(min = 26, max = 26))]
+    id: String,
+}
+
+impl Ref {
+    pub fn from(id: String) -> Result<Ref> {
+        Ok(Ref { id })
+    }
+
+    pub async fn fetch_user(self) -> Result<User> {
+        let doc = get_collection("users")
+            .find_one(
+                doc! {
+                    "_id": self.id
+                },
+                None
+            )
+            .await
+            .map_err(|_| Error::DatabaseError { operation: "find_one", with: "user" })?
+            .ok_or_else(|| Error::UnknownUser)?;
+        
+        Ok(
+            from_bson(Bson::Document(doc))
+                .map_err(|_| Error::DatabaseError { operation: "from_bson", with: "user" })?
+        )
+    }
+}
+
+impl<'r> FromParam<'r> for Ref {
+    type Error = &'r RawStr;
+
+    fn from_param(param: &'r RawStr) -> Result<Self, Self::Error> {
+        if let Ok(result) = Ref::from(param.to_string()) {
+            if result.validate().is_ok() {
+                return Ok(result);
+            }
+        }
+
+        Err(param)
+    }
+}