From da2cde9af35ed684d6c316ec2417b741026dc8b9 Mon Sep 17 00:00:00 2001
From: Joshua Potter <jrpotter2112@gmail.com>
Date: Wed, 26 Jul 2023 13:48:54 -0600
Subject: [PATCH] `declaration-data.js` changes up to `9b524d7`.

---
 static/declaration-data.js | 54 ++++++++++++++++++++++----------------
 1 file changed, 32 insertions(+), 22 deletions(-)

diff --git a/static/declaration-data.js b/static/declaration-data.js
index ae34585..291e09c 100644
--- a/static/declaration-data.js
+++ b/static/declaration-data.js
@@ -24,7 +24,7 @@ export class DeclarationDataCenter {
   /**
    * Used to implement the singleton, in case we need to fetch data mutiple times in the same page.
    */
-  static singleton = null;
+  static requestSingleton = null;
 
   /**
    * Construct a DeclarationDataCenter with given data.
@@ -41,26 +41,31 @@ export class DeclarationDataCenter {
    * @returns {Promise<DeclarationDataCenter>}
    */
   static async init() {
-    if (!DeclarationDataCenter.singleton) {
-      const dataListUrl = new URL(
-        `${SITE_ROOT}/declarations/declaration-data.bmp`,
-        window.location
-      );
-
-      // try to use cache first
-      const data = await fetchCachedDeclarationData().catch(_e => null);
-      if (data) {
-        // if data is defined, use the cached one.
-        DeclarationDataCenter.singleton = new DeclarationDataCenter(data);
-      } else {
-        // undefined. then fetch the data from the server.
-        const dataListRes = await fetch(dataListUrl);
-        const data = await dataListRes.json();
-        await cacheDeclarationData(data);
-        DeclarationDataCenter.singleton = new DeclarationDataCenter(data);
-      }
+    if (DeclarationDataCenter.requestSingleton === null) {
+      DeclarationDataCenter.requestSingleton = DeclarationDataCenter.getData();
+    }
+    return await DeclarationDataCenter.requestSingleton;
+  }
+
+  static async getData() {
+    const dataListUrl = new URL(
+      `${SITE_ROOT}/declarations/declaration-data.bmp`,
+      window.location
+    );
+
+    // try to use cache first
+    const data = await fetchCachedDeclarationData().catch(_e => null);
+    if (data) {
+      // if data is defined, use the cached one.
+      return new DeclarationDataCenter(data);
+    } else {
+      // undefined. then fetch the data from the server.
+      const dataListRes = await fetch(dataListUrl);
+      const data = await dataListRes.json();
+      // TODO https://github.com/leanprover/doc-gen4/issues/133
+      // await cacheDeclarationData(data);
+      return new DeclarationDataCenter(data);
     }
-    return DeclarationDataCenter.singleton;
   }
 
   /**
@@ -268,10 +273,15 @@ async function fetchCachedDeclarationData() {
   return new Promise((resolve, reject) => {
     let transactionRequest = store.get(CACHE_DB_KEY);
     transactionRequest.onsuccess = function (event) {
-      resolve(event.result);
+      // TODO: This API is not thought 100% through. If we have a DB cached
+      // already it will not even ask the remote for a new one so we end up
+      // with outdated declaration-data. This has to have some form of cache
+      // invalidation: https://github.com/leanprover/doc-gen4/issues/133
+      // resolve(event.target.result);
+      resolve(undefined);
     };
     transactionRequest.onerror = function (event) {
       reject(new Error(`fail to store declaration data`));
     };
   });
-}
+}
\ No newline at end of file