Studentify database clients and website API adapters

endpraesi/website/src/index.ts

@@ -10,13 +10,6 @@ const arangoKv = arango.collection("kv");
 
 type Timing = { op: string; key: string; ms: number };
 
-type Adapter = {
-  timings: Timing[];
-  getObject: (key: string) => Promise<any>;
-  getField: (key: string, field: string) => Promise<any>;
-  getIds: (key: string) => Promise<string[]>;
-};
-
 function stringifyObj(o: any) {
   if (!o) return null;
   const out: any = {};
@@ -24,74 +17,104 @@ function stringifyObj(o: any) {
   return out;
 }
 
-function redisAdapter(): Adapter {
+function getRedisAdapter() {
   const timings: Timing[] = [];
-  const track = async <T>(op: string, key: string, fn: () => Promise<T>): Promise<T> => {
-    const start = performance.now();
-    const res = await fn();
-    timings.push({ op, key, ms: performance.now() - start });
-    return res;
-  };
   return {
     timings,
-    getObject: (key) =>
-      track("hgetall", key, async () => {
-        const o = await redis.hgetall(key);
-        return o && Object.keys(o).length ? o : null;
-      }),
-    getField: (key, field) => track("hget", key, () => redis.hget(key, field)),
-    getIds: (key) => track("smembers", key, async () => (await redis.smembers(key)) || []),
+    async getObject(key: string) {
+      const start = performance.now();
+      const o = await redis.hgetall(key);
+      timings.push({ op: "hgetall", key, ms: performance.now() - start });
+      return o && Object.keys(o).length ? o : null;
+    },
+    async getField(key: string, field: string) {
+      const start = performance.now();
+      const res = await redis.hget(key, field);
+      timings.push({ op: "hget", key, ms: performance.now() - start });
+      return res;
+    },
+    async getIds(key: string) {
+      const start = performance.now();
+      const res = await redis.smembers(key);
+      timings.push({ op: "smembers", key, ms: performance.now() - start });
+      return res || [];
+    }
   };
 }
 
-function memcachedAdapter(): Adapter {
+function getMemcachedAdapter() {
   const timings: Timing[] = [];
-  const getJson = async (key: string) => {
+  
+  async function getJson(key: string) {
     const { value } = await memcached.get(key);
     return value ? JSON.parse(value.toString()) : null;
-  };
-  const track = async <T>(op: string, key: string, fn: () => Promise<T>): Promise<T> => {
-    const start = performance.now();
-    const res = await fn();
-    timings.push({ op, key, ms: performance.now() - start });
-    return res;
-  };
+  }
+
   return {
     timings,
-    getObject: (key) => track("get", key, async () => stringifyObj(await getJson(key))),
-    getField: (key, field) => track("get", key, async () => (await getJson(key))?.[field] ?? null),
-    getIds: (key) => track("get", key, async () => ((await getJson(key)) || []).map(String)),
+    async getObject(key: string) {
+      const start = performance.now();
+      const res = await getJson(key);
+      timings.push({ op: "get", key, ms: performance.now() - start });
+      return stringifyObj(res);
+    },
+    async getField(key: string, field: string) {
+      const start = performance.now();
+      const res = await getJson(key);
+      timings.push({ op: "get", key, ms: performance.now() - start });
+      return res ? res[field] : null;
+    },
+    async getIds(key: string) {
+      const start = performance.now();
+      const res = await getJson(key);
+      timings.push({ op: "get", key, ms: performance.now() - start });
+      return res ? res.map(String) : [];
+    }
   };
 }
 
-function arangoAdapter(): Adapter {
+function getArangoAdapter() {
   const timings: Timing[] = [];
-  const getVal = async (key: string) => {
+
+  async function getVal(key: string) {
     const doc = await arangoKv.document(key, { graceful: true });
     return doc ? doc.value : null;
-  };
-  const track = async <T>(op: string, key: string, fn: () => Promise<T>): Promise<T> => {
-    const start = performance.now();
-    const res = await fn();
-    timings.push({ op, key, ms: performance.now() - start });
-    return res;
-  };
+  }
+
   return {
     timings,
-    getObject: (key) => track("document", key, async () => stringifyObj(await getVal(key))),
-    getField: (key, field) => track("document", key, async () => (await getVal(key))?.[field] ?? null),
-    getIds: (key) => track("document", key, async () => ((await getVal(key)) || []).map(String)),
+    async getObject(key: string) {
+      const start = performance.now();
+      const res = await getVal(key);
+      timings.push({ op: "document", key, ms: performance.now() - start });
+      return stringifyObj(res);
+    },
+    async getField(key: string, field: string) {
+      const start = performance.now();
+      const res = await getVal(key);
+      timings.push({ op: "document", key, ms: performance.now() - start });
+      return res ? res[field] : null;
+    },
+    async getIds(key: string) {
+      const start = performance.now();
+      const res = await getVal(key);
+      timings.push({ op: "document", key, ms: performance.now() - start });
+      return res ? res.map(String) : [];
+    }
   };
 }
 
-function getAdapter(db: string): Adapter {
-  if (db === "memcached") return memcachedAdapter();
-  if (db === "arangodb") return arangoAdapter();
-  return redisAdapter();
+function getAdapter(db: string) {
+  if (db === "memcached") return getMemcachedAdapter();
+  if (db === "arangodb") return getArangoAdapter();
+  return getRedisAdapter();
 }
 
 function timingSummary(timings: Timing[]) {
-  const total = timings.reduce((s, t) => s + t.ms, 0);
+  let total = 0;
+  for (const t of timings) {
+    total += t.ms;
+  }
   return { count: timings.length, total, ops: timings };
 }