PlugOS refactor and other tweaks (#631)

* Prep for in-process plug loading (e.g. for CF workers, Deno Deploy)
* Prototype of fixed in-process loading plugs
* Fix: buttons not to scroll with content
* Better positioning of modal especially on mobile
* Move query caching outside query
* Fix annoying mouse behavior when filter box appears
* Page navigator search tweaks

plug-api/lib/async.ts

@@ -37,24 +37,24 @@ export class PromiseQueue {
     resolve: (value: any) => void;
     reject: (error: any) => void;
   }[] = [];
-  private running = false;
+  private processing = false;
 
   runInQueue(fn: () => Promise<any>): Promise<any> {
     return new Promise((resolve, reject) => {
       this.queue.push({ fn, resolve, reject });
-      if (!this.running) {
-        this.run();
+      if (!this.processing) {
+        this.process();
       }
     });
   }
 
-  private async run(): Promise<void> {
+  private async process(): Promise<void> {
     if (this.queue.length === 0) {
-      this.running = false;
+      this.processing = false;
       return;
     }
 
-    this.running = true;
+    this.processing = true;
     const { fn, resolve, reject } = this.queue.shift()!;
 
     try {
@@ -64,7 +64,7 @@ export class PromiseQueue {
       reject(error);
     }
 
-    this.run(); // Continue processing the next promise in the queue
+    this.process(); // Continue processing the next promise in the queue
   }
 }
 

plug-api/lib/frontmatter.ts

@@ -7,6 +7,7 @@ import {
   replaceNodesMatchingAsync,
   traverseTreeAsync,
 } from "$sb/lib/tree.ts";
+import { expandPropertyNames } from "$sb/lib/json.ts";
 
 export type FrontMatter = { tags?: string[] } & Record<string, any>;
 
@@ -116,6 +117,8 @@ export async function extractFrontmatter(
   data.tags = [...new Set([...tags.map((t) => t.replace(/^#/, ""))])];
 
   // console.log("Extracted tags", data.tags);
+  // Expand property names (e.g. "foo.bar" => { foo: { bar: true } })
+  data = expandPropertyNames(data);
 
   return data;
 }

plug-api/lib/limited_map.test.ts

@@ -0,0 +1,23 @@
+import { sleep } from "$sb/lib/async.ts";
+import { assertEquals } from "../../test_deps.ts";
+import { LimitedMap } from "./limited_map.ts";
+
+Deno.test("limited map", async () => {
+  const mp = new LimitedMap<string>(3);
+  mp.set("a", "a");
+  mp.set("b", "b", 5);
+  mp.set("c", "c");
+  assertEquals(mp.get("a"), "a");
+  assertEquals(mp.get("b"), "b");
+  assertEquals(mp.get("c"), "c");
+  // Drops the first key
+  mp.set("d", "d");
+  // console.log(mp.toJSON());
+  assertEquals(mp.get("a"), undefined);
+  await sleep(10);
+  // "b" should have been dropped
+  assertEquals(mp.get("b"), undefined);
+  assertEquals(mp.get("c"), "c");
+
+  console.log(mp.toJSON());
+});

plug-api/lib/limited_map.ts

@@ -0,0 +1,72 @@
+type LimitedMapRecord<V> = {
+  value: V;
+  la: number;
+  expTimer?: number;
+};
+
+export class LimitedMap<V> {
+  private map: Map<string, LimitedMapRecord<V>>;
+
+  constructor(
+    private maxSize: number,
+    initialJson: Record<string, LimitedMapRecord<V>> = {},
+  ) {
+    this.map = new Map(Object.entries(initialJson));
+  }
+
+  /**
+   * @param key
+   * @param value
+   * @param ttl time to live (in ms)
+   */
+  set(key: string, value: V, ttl?: number) {
+    const entry: LimitedMapRecord<V> = { value, la: Date.now() };
+    if (ttl) {
+      const existingEntry = this.map.get(key);
+      if (existingEntry?.expTimer) {
+        clearTimeout(existingEntry.expTimer);
+      }
+      entry.expTimer = setTimeout(() => {
+        this.map.delete(key);
+      }, ttl);
+    }
+    if (this.map.size >= this.maxSize) {
+      // Remove the oldest key before adding a new one
+      const oldestKey = this.getOldestKey();
+      this.map.delete(oldestKey!);
+    }
+    this.map.set(key, entry);
+  }
+
+  get(key: string): V | undefined {
+    const entry = this.map.get(key);
+    if (entry) {
+      // Update the last accessed timestamp
+      entry.la = Date.now();
+      return entry.value;
+    }
+    return undefined;
+  }
+
+  remove(key: string) {
+    this.map.delete(key);
+  }
+
+  toJSON() {
+    return Object.fromEntries(this.map.entries());
+  }
+
+  private getOldestKey(): string | undefined {
+    let oldestKey: string | undefined;
+    let oldestTimestamp: number | undefined;
+
+    for (const [key, entry] of this.map.entries()) {
+      if (!oldestTimestamp || entry.la < oldestTimestamp) {
+        oldestKey = key;
+        oldestTimestamp = entry.la;
+      }
+    }
+
+    return oldestKey;
+  }
+}

plug-api/lib/memory_cache.test.ts

@@ -0,0 +1,17 @@
+import { sleep } from "$sb/lib/async.ts";
+import { ttlCache } from "$sb/lib/memory_cache.ts";
+import { assertEquals } from "../../test_deps.ts";
+
+Deno.test("Memory cache", async () => {
+  let calls = 0;
+  async function expensiveFunction(key: string) {
+    calls++;
+    await sleep(1);
+    return key;
+  }
+  assertEquals("key", await ttlCache("key", expensiveFunction, 0.01));
+  assertEquals(1, calls);
+  assertEquals("key", await ttlCache("key", expensiveFunction, 0.01));
+  assertEquals(1, calls);
+  await sleep(10);
+});

plug-api/lib/memory_cache.ts

@@ -0,0 +1,21 @@
+import { LimitedMap } from "$sb/lib/limited_map.ts";
+
+const cache = new LimitedMap<any>(50);
+
+export async function ttlCache<K, V>(
+  key: K,
+  fn: (key: K) => Promise<V>,
+  ttlSecs?: number,
+): Promise<V> {
+  if (!ttlSecs) {
+    return fn(key);
+  }
+  const serializedKey = JSON.stringify(key);
+  const cached = cache.get(serializedKey);
+  if (cached) {
+    return cached;
+  }
+  const result = await fn(key);
+  cache.set(serializedKey, result, ttlSecs * 1000);
+  return result;
+}

plug-api/plugos-syscall/asset.ts

@@ -2,10 +2,11 @@ import { base64DecodeDataUrl } from "../../plugos/asset_bundle/base64.ts";
 import { syscall } from "./syscall.ts";
 
 export async function readAsset(
+  plugName: string,
   name: string,
   encoding: "utf8" | "dataurl" = "utf8",
 ): Promise<string> {
-  const dataUrl = await syscall("asset.readAsset", name) as string;
+  const dataUrl = await syscall("asset.readAsset", plugName, name) as string;
   switch (encoding) {
     case "utf8":
       return new TextDecoder().decode(base64DecodeDataUrl(dataUrl));

plug-api/types.ts

@@ -73,11 +73,6 @@ export type Query = {
   render?: string;
   renderAll?: boolean;
   distinct?: boolean;
-
-  /**
-   * When set, the DS implementation _may_ cache the result for the given number of seconds.
-   */
-  cacheSecs?: number;
 };
 
 export type KvQuery = Omit<Query, "querySource"> & {