37 lines
1.3 KiB
JavaScript
37 lines
1.3 KiB
JavaScript
// checkObjProps take an untrusted object and a list of typechecks to perform
|
|
// and will check that the object adheres to the typechecks. If a type is
|
|
// missing or has the wrong type, an error will be returned. This is intended
|
|
// to be used to check untrusted objects after they get decoded from JSON. This
|
|
// is particularly useful when receiving objects from untrusted entities over
|
|
// the network or over postMessage.
|
|
//
|
|
// Below is an example object, followed by the call that you would make to
|
|
// checkObj to verify the object.
|
|
//
|
|
// const expectedObj = {
|
|
// aNum: 35,
|
|
// aStr: "hi",
|
|
// aBig: 10n,
|
|
// };
|
|
//
|
|
// const err = checkObjProps(expectedObj, [
|
|
// ["aNum", "number"],
|
|
// ["aStr", "string"],
|
|
// ["aBig", "bigint"],
|
|
// ]);
|
|
//
|
|
// Over time, we intend to extend this function to support more types than just
|
|
// the default types supported by javascript. For example, we intend to add
|
|
// special cases for arrays, and for cryptographic objects.
|
|
function checkObjProps(obj, checks) {
|
|
for (let i = 0; i < checks.length; i++) {
|
|
const check = checks[i];
|
|
const type = typeof obj[check[0]];
|
|
if (type !== check[1]) {
|
|
return "check failed, expecting " + check[1] + " got " + type;
|
|
}
|
|
}
|
|
return null;
|
|
}
|
|
export { checkObjProps };
|