feature/IO-3052-Skia-Canvas-Handler: Fix missing checks

Signed-off-by: Dave Richer <dave@imexsystems.ca>

server/middleware/validateCanvasInputMiddleware.js

@@ -1,7 +1,7 @@
 const { isObject } = require("lodash");
 
 const validateCanvasInputMiddleware = (req, res, next) => {
-  const { values, keys, override } = req.body;
+  const { values, keys, override, w, h } = req.body;
 
   if (!Array.isArray(values) || !Array.isArray(keys)) {
     return res.status(400).send("Invalid input: 'values' and 'keys' must be arrays.");
@@ -19,6 +19,13 @@ const validateCanvasInputMiddleware = (req, res, next) => {
     return res.status(400).send("Override must be an object");
   }
 
+  if (w && (!Number.isFinite(w) || w <= 0)) {
+    return res.status(400).send("Width must be a positive number");
+  }
+  if (h && (!Number.isFinite(h) || h <= 0)) {
+    return res.status(400).send("Height must be a positive number");
+  }
+
   next(); // Proceed to the next middleware or route handler
 };