Include njodb statically & fix write stream issue

server/njodb/validators.js

@@ -0,0 +1,69 @@
+"use strict";
+
+const { existsSync } = require("graceful-fs");
+
+const validateSize = (s) => {
+    if (typeof s !== "number") {
+        throw new TypeError("Size must be a number");
+    } else if (s <= 0) {
+        throw new RangeError("Size must be greater than zero");
+    }
+
+    return s;
+};
+
+const validateName = (n) => {
+    if (typeof n !== "string") {
+        throw new TypeError("Name must be a string");
+    } else if (n.trim().length <= 0) {
+        throw new Error("Name must be a non-blank string")
+    }
+
+    return n;
+};
+
+const validatePath = (p) => {
+    if (typeof p !== "string") {
+        throw new TypeError("Path must be a string");
+    } else if (p.trim().length <= 0) {
+        throw new Error("Path must be a non-blank string");
+    } else if (!existsSync(p)) {
+        throw new Error("Path does not exist");
+    }
+
+    return p;
+};
+
+const validateArray = (a) => {
+    if (!Array.isArray(a)) {
+        throw new TypeError("Not an array");
+    }
+
+    return a;
+};
+
+const validateObject = (o) => {
+    if (typeof o !== "object") {
+        throw new TypeError("Not an object");
+    }
+
+    return o;
+};
+
+const validateFunction = (f) => {
+    if (typeof f !== "function") {
+        throw new TypeError("Not a function")
+    } else {
+        const fString = f.toString();
+        if (/\s*function/.test(fString) && !/\W+return\W+/.test(fString)) throw new Error("Function must return a value");
+    }
+
+    return f;
+}
+
+exports.validateSize = validateSize;
+exports.validateName = validateName;
+exports.validatePath = validatePath;
+exports.validateArray = validateArray;
+exports.validateObject = validateObject;
+exports.validateFunction = validateFunction;