From 9c5342a053e530113f7f2bb459c215c4863e8545 Mon Sep 17 00:00:00 2001
From: realaravinth <realaravinth@batsense.net>
Date: Thu, 25 Nov 2021 12:35:47 +0530
Subject: [PATCH] light weight graphql query to fetch data to construct post
 URL

---
 schemas/query.graphql  | 10 ++++++++++
 schemas/schema.graphql |  1 +
 src/data.rs            | 41 ++++++++++++++++++++++++++++++++++++++++-
 src/proxy.rs           |  9 ++++-----
 4 files changed, 55 insertions(+), 6 deletions(-)

diff --git a/schemas/query.graphql b/schemas/query.graphql
index 6a1768f..3bc9943 100644
--- a/schemas/query.graphql
+++ b/schemas/query.graphql
@@ -8,6 +8,7 @@ query GetPost($id: ID!) {
             name
             id
 			imageId
+            username
         }
         previewImage {
             id
@@ -49,3 +50,12 @@ query GetPost($id: ID!) {
         }
     }
 }
+
+query GetPostLight($id: ID!) {
+    post(id: $id) {
+        uniqueSlug
+        creator {
+            username
+        }
+    }
+}
diff --git a/schemas/schema.graphql b/schemas/schema.graphql
index ec6a74e..b0ec1ab 100644
--- a/schemas/schema.graphql
+++ b/schemas/schema.graphql
@@ -55,6 +55,7 @@ type User {
     id: String!
     name: String!
     imageId: String!
+    username: String!
 }
 
 type Post {
diff --git a/src/data.rs b/src/data.rs
index 2d49398..6be4bd3 100644
--- a/src/data.rs
+++ b/src/data.rs
@@ -26,7 +26,7 @@ use sled::{Db, Tree};
 use crate::proxy::StringUtils;
 use crate::SETTINGS;
 
-const POST_CACHE_VERSION: usize = 2;
+const POST_CACHE_VERSION: usize = 3;
 const GIST_CACHE_VERSION: usize = 1;
 
 #[derive(Clone)]
@@ -87,6 +87,20 @@ impl GistFile {
     }
 }
 
+#[derive(GraphQLQuery)]
+#[graphql(
+    schema_path = "schemas/schema.graphql",
+    query_path = "schemas/query.graphql",
+    response_derives = "Debug, Serialize, Deserialize, Clone"
+)]
+pub struct GetPostLight;
+
+#[derive(Debug, Clone)]
+pub struct PostUrl {
+    pub slug: String,
+    pub username: String,
+}
+
 impl Data {
     pub fn new() -> AppData {
         let path = Path::new(SETTINGS.cache.as_ref().unwrap()).join("posts_cache");
@@ -152,6 +166,31 @@ impl Data {
         }
     }
 
+    pub async fn get_post_light(&self, id: &str) -> PostUrl {
+        match self.posts.get(id) {
+            Ok(Some(v)) => {
+                let cached: PostResp = bincode::deserialize(&v[..]).unwrap();
+                PostUrl {
+                    slug: cached.unique_slug,
+                    username: cached.creator.username,
+                }
+            }
+            _ => {
+                let vars = get_post_light::Variables { id: id.to_owned() };
+                const URL: &str = "https://medium.com/_/graphql";
+
+                let res = post_graphql::<GetPostLight, _>(&self.client, URL, vars)
+                    .await
+                    .unwrap();
+                let res = res.data.expect("missing response data").post.unwrap();
+                PostUrl {
+                    slug: res.unique_slug,
+                    username: res.creator.username,
+                }
+            }
+        }
+    }
+
     pub async fn get_gist(&self, id: String) -> (String, GistContent) {
         match self.gists.get(&id) {
             Ok(Some(v)) => (id, bincode::deserialize(&v[..]).unwrap()),
diff --git a/src/proxy.rs b/src/proxy.rs
index 43c0d69..45a2d3c 100644
--- a/src/proxy.rs
+++ b/src/proxy.rs
@@ -151,14 +151,13 @@ async fn assets(path: web::Path<String>, data: AppData) -> impl Responder {
 
 #[my_codegen::get(path = "crate::V1_API_ROUTES.proxy.by_post_id")]
 async fn by_post_id(path: web::Path<String>, data: AppData) -> impl Responder {
-    let post_data = data.get_post(&path).await;
-    let author = format!("@{}", post_data.creator.username);
+    let post_data = data.get_post_light(&path).await;
     HttpResponse::Found()
         .append_header((
             header::LOCATION,
             crate::V1_API_ROUTES
                 .proxy
-                .get_page(&author, &post_data.unique_slug),
+                .get_page(&post_data.username, &post_data.slug),
         ))
         .finish()
 }
@@ -260,8 +259,8 @@ mod tests {
         }
 
         let urls = vec![
-            "/@ftrain/big-data-small-effort-b62607a43a8c",
-            "/@shawn-shi/rest-api-best-practices-decouple-long-running-tasks-from-http-request-processing-9fab2921ace8",
+            "/ftrain/big-data-small-effort-b62607a43a8c",
+            "/shawn-shi/rest-api-best-practices-decouple-long-running-tasks-from-http-request-processing-9fab2921ace8",
         ];
 
         for uri in urls.iter() {