add server settings api

apps/ignis-server/server/routes/settings.js

@@ -0,0 +1,92 @@
+const express = require("express");
+const { writeCoalescer } = require("@ignis/server-core");
+const settings = require("../settings");
+const bootstrapRoutes = require("./bootstrap");
+
+const router = express.Router();
+
+const NUMBER_KEYS = [
+  "contentCacheBytes",
+  "inputCacheBytes",
+  "inputCacheTtlMs",
+  "writeCoalesceMs",
+  "maxBodyBytes",
+];
+const LIST_KEYS = ["proxyAllowlist", "wsOrigins"];
+
+function validate(body) {
+  const clean = {};
+
+  for (const key of NUMBER_KEYS) {
+    if (body[key] === undefined) {
+      continue;
+    }
+
+    const n = body[key];
+
+    if (!Number.isInteger(n) || n < 0) {
+      throw new Error(`${key} must be a non-negative integer`);
+    }
+
+    if (key === "maxBodyBytes" && (n < 1 || n > settings.MAX_BODY_BACKSTOP)) {
+      throw new Error(
+        `maxBodyBytes must be between 1 and ${settings.MAX_BODY_BACKSTOP}`,
+      );
+    }
+
+    clean[key] = n;
+  }
+
+  for (const key of LIST_KEYS) {
+    if (body[key] === undefined) {
+      continue;
+    }
+
+    const list = body[key];
+
+    if (
+      !Array.isArray(list) ||
+      list.some((v) => typeof v !== "string" || !v.trim())
+    ) {
+      throw new Error(`${key} must be an array of non-empty strings`);
+    }
+
+    clean[key] = list.map((v) => v.trim());
+  }
+
+  return clean;
+}
+
+function applySettings(effective, req) {
+  writeCoalescer.configure({ writeCoalesceMs: effective.writeCoalesceMs });
+
+  const wss = req.app.get("wss");
+
+  if (wss && typeof wss.setOriginAllowlist === "function") {
+    wss.setOriginAllowlist(effective.wsOrigins);
+  }
+}
+
+router.get("/", (req, res) => {
+  res.json(settings.getAll());
+});
+
+router.post("/", (req, res) => {
+  let clean;
+
+  try {
+    clean = validate(req.body || {});
+  } catch (e) {
+    return res.status(400).json({ error: e.message });
+  }
+
+  const effective = settings.update(clean);
+  applySettings(effective, req);
+
+  // Cache sizes ride in the bootstrap response; clear it so the next page load picks up new values.
+  bootstrapRoutes.invalidateAll();
+
+  res.json(effective);
+});
+
+module.exports = router;