Fixes #8: SETTINGS page to keep all settings

packages/plugs/lib/settings_page.ts

@@ -0,0 +1,23 @@
+import { readYamlPage } from "./yaml_page";
+
+export async function readSettings<T extends object>(settings: T): Promise<T> {
+  try {
+    let allSettings = (await readYamlPage("SETTINGS", ["yaml"])) || {};
+    // TODO: I'm sure there's a better way to type this than "any"
+    let collectedSettings: any = {};
+    for (let [key, defaultVal] of Object.entries(settings)) {
+      if (allSettings[key]) {
+        collectedSettings[key] = allSettings[key];
+      } else {
+        collectedSettings[key] = defaultVal;
+      }
+    }
+    return collectedSettings as T;
+  } catch (e: any) {
+    if (e.message === "Page not found") {
+      // No settings yet, return default values for all
+      return settings;
+    }
+    throw e;
+  }
+}

packages/plugs/lib/yaml_page.ts

@@ -0,0 +1,42 @@
+import { findNodeOfType, traverseTree } from "@silverbulletmd/common/tree";
+import { parseMarkdown } from "@silverbulletmd/plugos-silverbullet-syscall/markdown";
+import { readPage } from "@silverbulletmd/plugos-silverbullet-syscall/space";
+import YAML from "yaml";
+
+export async function readYamlPage(
+  pageName: string,
+  allowedLanguages = ["yaml"]
+): Promise<any> {
+  const { text } = await readPage(pageName);
+  let tree = await parseMarkdown(text);
+  let data: any = {};
+
+  traverseTree(tree, (t): boolean => {
+    // Find a fenced code block
+    if (t.type !== "FencedCode") {
+      return false;
+    }
+    let codeInfoNode = findNodeOfType(t, "CodeInfo");
+    if (!codeInfoNode) {
+      return false;
+    }
+    if (!allowedLanguages.includes(codeInfoNode.children![0].text!)) {
+      return false;
+    }
+    let codeTextNode = findNodeOfType(t, "CodeText");
+    if (!codeTextNode) {
+      // Honestly, this shouldn't happen
+      return false;
+    }
+    let codeText = codeTextNode.children![0].text!;
+    try {
+      data = YAML.parse(codeText);
+    } catch (e: any) {
+      console.error("YAML Page parser error", e);
+      throw new Error(`YAML Error: ${e.message}`);
+    }
+    return true;
+  });
+
+  return data;
+}