add validation

Author: sameer2210

backend/src/middleware/validate.middleware.js

@@ -0,0 +1,106 @@
+const formatValidationErrors = (error) => {
+  if (!error) return ["Invalid request"];
+
+  if (Array.isArray(error)) {
+    return error
+      .map((item) => item?.message || item?.msg || (typeof item === "string" ? item : null))
+      .filter(Boolean);
+  }
+
+  if (Array.isArray(error.errors)) {
+    return error.errors
+      .map((item) => item?.message || item?.msg || (typeof item === "string" ? item : null))
+      .filter(Boolean);
+  }
+
+  if (Array.isArray(error.details)) {
+    return error.details
+      .map((detail) => detail?.message || detail?.msg || (typeof detail === "string" ? detail : null))
+      .filter(Boolean);
+  }
+
+  if (Array.isArray(error.issues)) {
+    return error.issues
+      .map((issue) => issue?.message || issue?.msg || (typeof issue === "string" ? issue : null))
+      .filter(Boolean);
+  }
+
+  if (error.message) return [error.message];
+
+  return ["Invalid request"];
+};
+
+export const validate = (schema, source = "body") => (req, res, next) => {
+  if (!schema) return next();
+
+  const data = req[source];
+
+  try {
+    if (typeof schema.safeParse === "function") {
+      const result = schema.safeParse(data);
+      if (!result.success) {
+        res.status(400);
+        const errors = formatValidationErrors(result.error);
+        return next(new Error(errors.join(", ")));
+      }
+      req[source] = result.data;
+      return next();
+    }
+
+    if (typeof schema.parse === "function") {
+      const parsed = schema.parse(data);
+      req[source] = parsed;
+      return next();
+    }
+
+    if (typeof schema.validate === "function") {
+      const { error, value } = schema.validate(data, {
+        abortEarly: false,
+        stripUnknown: true,
+      });
+      if (error) {
+        res.status(400);
+        const errors = formatValidationErrors(error);
+        return next(new Error(errors.join(", ")));
+      }
+      if (value !== undefined) {
+        req[source] = value;
+      }
+      return next();
+    }
+
+    if (typeof schema === "function") {
+      const result = schema(data, req);
+      if (result === true || result === undefined) return next();
+      if (result === false) {
+        res.status(400);
+        return next(new Error("Validation failed"));
+      }
+      if (typeof result === "string") {
+        res.status(400);
+        return next(new Error(result));
+      }
+      if (Array.isArray(result)) {
+        res.status(400);
+        return next(new Error(result.join(", ")));
+      }
+      if (result && result.error) {
+        res.status(400);
+        const errors = formatValidationErrors(result.error);
+        return next(new Error(errors.join(", ")));
+      }
+      return next();
+    }
+
+    return next();
+  } catch (error) {
+    if (res.statusCode === 200) {
+      res.status(400);
+    }
+    return next(error);
+  }
+};
+
+export const validateBody = (schema) => validate(schema, "body");
+export const validateParams = (schema) => validate(schema, "params");
+export const validateQuery = (schema) => validate(schema, "query");