acl-example-code.js

const OBJECTTYPES = {
    FILES: 1,
    DIRECTORIES: 2
};

const FILEACTIONS = {
    READ: 1,
    WRITE: 2
};

const DIRECTORYACTIONS = {
    READ: 1,
    WRITE: 2
};

var helloAcl = {
    "Alice": [ FILEACTIONS.READ, FILEACTIONS.WRITE ],
    "Bob": [ FILEACTIONS.READ ]
};

var documentsAcl = {
    "Alice": [ DIRECTORYACTIONS.READ, DIRECTORYACTIONS.WRITE ],
    "Bob": [ DIRECTORYACTIONS.READ ]
}

var objects = {
    "hello.txt": { name: "hello.txt", type: OBJECTTYPES.FILES, acl: helloAcl },
    "documents": { name: "documents", type: OBJECTTYPES.DIRECTORIES, acl: documentsAcl }    
};

function check(subject, action, object) {
    
    if (object.acl[subject].includes(action)) {
        return true;
    }
    
    return false;
}

console.log(check("Alice", FILEACTIONS.WRITE, objects["hello.txt"]));
console.log(check("Bob", FILEACTIONS.WRITE, objects["hello.txt"]));