Resolution to Issue #313: Error alert for invalid email entry (#320)

* Added ability to access error message/ conditional for invalid email

* added try catch

* renaming variables, adding conditional

src/pages/students/index.tsx

@@ -13,10 +13,30 @@ const Students = () => {
   const createStudent = trpc.case_manager.addStudent.useMutation({
     onSuccess: () => utils.case_manager.getMyStudentsAndIepInfo.invalidate(),
     // TODO(tessa): In a future PR, we could change this to notification instead of browser alert
-    onError: () =>
-      alert(
-        `This student is already assigned to a case manager. Please check your roster if the student is already there. Otherwise, this student is with another case manager.`
-      ),
+    onError: (err) => {
+      // err allows one to access validation, code, message, and path
+      // JSON.parse is utilized because err.message is a string
+      try {
+        const formattedErr = JSON.parse(err.message) as {
+          validation: string;
+          code: string;
+          message: string;
+          path: string[];
+        }[];
+
+        if (formattedErr[0].message == "Invalid email") {
+          alert("The provided email is in the incorrect format- please edit.");
+        }
+        //  can later insert other error messages here, as needed
+        else {
+          alert("An error has occurred.");
+        }
+      } catch {
+        alert(
+          `This student is already assigned to a case manager. Please check your roster if the student is already there. Otherwise, this student is with another case manager.`
+        );
+      }
+    },
   });
 
   // create editStudent