headers modified tests for static handling

modified.js

function modified(req, headers) {
    var modifiedSince = req.headers['if-modified-since'],
        lastModified = headers['Last-Modified'],
        noneMatch = req.headers['if-none-match'],
        etag = headers.ETag,
        etagModified = true,
        dateModified = true;
    // Check If-None-Match
    if (noneMatch && etag && noneMatch === etag) {
        etagModified = false;
    }

    // Check If-Modified-Since
    if (modifiedSince && lastModified) {
        modifiedSince = new Date(modifiedSince);
        lastModified = new Date(lastModified);
        // Ignore invalid dates
        if (!isNaN(modifiedSince.getTime())) {
            if (lastModified <= modifiedSince) {
                dateModified = false;
            }
        }
    }

    return etagModified || dateModified;
}

// testing modified data
// 1. same
console.log(modified({
    headers: {
        'if-modified-since': 'Fri, 30 Nov 2012 21:07:52 GMT',
        'if-none-match': 123
    }
}, {
    'Last-Modified': 'Fri, 30 Nov 2012 21:07:52 GMT',
    'ETag': 123
}));

// 2. req is older
console.log(modified({
    headers: {
        'if-modified-since': 'Fri, 30 Nov 2012 21:01:52 GMT',
        'if-none-match': 123
    }
}, {
    'Last-Modified': 'Fri, 30 Nov 2012 21:07:52 GMT',
    'ETag': 123
}));

// 3. req is newer
console.log(modified({
    headers: {
        'if-modified-since': 'Fri, 30 Nov 2012 21:09:52 GMT',
        'if-none-match': 123
    }
}, {
    'Last-Modified': 'Fri, 30 Nov 2012 21:07:52 GMT',
    'ETag': 123
}));

// 4. invalid
console.log(modified({
    headers: {
        'if-none-match': 123
    }
}, {
    'Last-Modified': 'Fri, 30 Nov 2012 21:07:52 GMT',
    'ETag': 123
}));

// testing etag data
// 1. same (yes duplicated)
console.log(modified({
    headers: {
        'if-modified-since': 'Fri, 30 Nov 2012 21:07:52 GMT',
        'if-none-match': 123
    }
}, {
    'Last-Modified': 'Fri, 30 Nov 2012 21:07:52 GMT',
    'ETag': 123
}));

// 1. different
console.log(modified({
    headers: {
        'if-modified-since': 'Fri, 30 Nov 2012 21:07:52 GMT',
        'if-none-match': 123
    }
}, {
    'Last-Modified': 'Fri, 30 Nov 2012 21:07:52 GMT',
    'ETag': 321
}));

// 1. invalid
console.log(modified({
    headers: {
        'if-modified-since': 'Fri, 30 Nov 2012 21:07:52 GMT'
    }
}, {
    'Last-Modified': 'Fri, 30 Nov 2012 21:07:52 GMT',
    'ETag': 321
}));