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geraintluff
Default format validators
The JSON draft-4 schema suggests that if the optional support for the format keywords is available then the validator should (not must) also support a number of default formats. tv4 does not contain these but I have found it useful to have them. I believe these implementations to be correct but they may not necessarily be efficient:)
function defaultFormatValidators() {
/**
* The JSON Schema draft-04 says these formats SHOULD be support if a validator implements
* support for the format keyword.
*
* tv4 requires a null return value for a pass or a string to indicate an error.
*/
var valDateTime = function(data, schema) {
// A string instance is valid against this attribute if it is a valid date
// representation as defined by RFC 3339, section 5.6 [RFC3339].
// Based on http://stackoverflow.com/questions/11318634/how-to-convert-date-in-rfc-3339-to-the-javascript-date-objectmilliseconds-since
var getDom = function(month, year) {
var domTable = [ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 ];
if(month == 2) {
if((year % 4 == 0) && ((year % 100 != 0) || (year % 400 == 0))) {
domTable[month-1] = 29;
}
}
return(domTable[month-1]);
};
var matchDateRegEx = /^([0-9]{4})-(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):([0-4][0-9]|5[0-9]):([0-5][0-9]|60)(\.[0-9]+)?(Z|([+-][01][0-9]|2[0-3]):([0-4][0-9]|5[0-9]))$/;
try {
var m = matchDateRegEx.exec(data);
if(!m) { throw 'failed to match regex'; }
var year = +m[1]; // 4DIGIT : Any 4 digits
var month = +m[2]; // 2DIGIT : 01-12
var day = +m[3]; // 2DIGIT : 01-28, 01-29, 01-30, 01-31
if(day > getDom(month, year)) { throw 'invalid number of days for month'; }
var hour = +m[4]; // 2DIGIT : 00-23
var minute = +m[5]; // 2DIGIT : 00-59
var second = +m[6]; // 2DIGIT : 00-58, 00-59, 00-60 based on leap second rules
var msec = +m[7]; // 1*DIGIT: (optional)
var tzHour = +m[8]; // 2DIGIT : 00-23
var tzMin = +m[9]; // 2DIGIT : 00-59
return(null);
}
catch(e) {
return('Invalid data for format date-time: ' + e);
}
};
var valEmail = function(data, schema) {
// A string instance is valid against this attribute if it is a valid Internet
// email address as defined by RFC 5322, section 3.4.1 [RFC5322]
try {
var parts = data.split('@');
if(!parts || (parts.length != 2)) {
throw 'wrong number of @';
}
// local-part regex from http://www.regular-expressions.info/email.html
if(!parts[0].match(/^(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*")$/)) {
throw 'local-part failed validation';
}
if(valHostname(parts[1], schema)) {
throw 'hostname failed validation';
}
}
catch(e) {
return('Invalid data for format email: ' + e);
}
};
var valHostname = function(data, schema) {
// A string instance is valid against this attribute if it is a valid
// representation for an Internet host name, as defined by
// RFC 1034, section 3.1 [RFC1034].
try {
// Total length not > 255
if(data.length > 255) { throw 'length too long'; }
var parts = data.split(".");
for(pidx in parts) {
var p = parts[pidx];
// Leading character [a-z]
// Optionally [0-9a-z-] upto 61 times
// Trailing character [0-9a-z]
if(!p.toLowerCase().match(/^[a-z][0-9a-z-]{0,61}[a-z0-9]$/)) {
throw 'invalid label: ' + p
}
}
return(null);
}
catch(e) {
return('Invalid data for format hostname: ' + e);
}
};
var valIpv4 = function(data, schema) {
// A string instance is valid against this attribute if it is a valid
// representation of an IPv4 address according to the "dotted-quad" ABNF
// syntax as defined in RFC 2673, section 3.2 [RFC2673].
// dotted-quad = decbyte "." decbyte "." decbyte "." decbyte
// decbyte = 1*3DIGIT
// Each number represented by a <decbyte> must be between 0 and 255, inclusive.
if(data.match(/^((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$/)) {
return(null);
}
return('Invalid data for format ipv4');
};
var valIpv6 = function(data, schema) {
// A string instance is valid against this attribute if it is a valid representation
// of an IPv6 address as defined in RFC 2373, section 2.2 [RFC2373].
// Replace :: with 0 sections to get to a basic version
if(data.match(/::/)) {
var tgtColon = 7;
// If we have an IPv4 compat version the target number of : is 6
if(data.match(/((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$/)) {
tgtColon = 6;
}
// Handle :: at beginning/end of data
if(data.match(/^::/)) {
data = data.replace('::', '0::');
}
if(data.match(/::$/)) {
data = data.replace('::', '::0');
}
// Expand ::
while(data.match(/:/g).length < tgtColon) {
data = data.replace('::', ':0::');
}
// Replace final ::
data = data.replace('::', ':0:');
}
// The basic version is x:x:x:x:x:x:x:x
if(data.match(/^([0-9a-fA-F]{1,4}:){7}[0-9a-fA-F]{1,4}$/)) {
return(null);
}
// The IPv4 compat version x:x:x:x:x:x:d.d.d.d
if(data.match(/^([0-9a-fA-F]{1,4}:){6}((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$/)) {
return(null);
}
return('Invalid data for format ipv6');
};
var valUri = function(data, schema) {
// A string instance is valid against this attribute if it is a valid URI, according to [RFC3986].
// From http://xml.resource.org/public/rfc/html/rfc3986.html#regexp
if(data.match(/^(([^:\/?#]+):)?(\/\/([^\/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?/)) {
return(null);
}
//var parts = data.match(/^(([^:\/?#]+):)?(\/\/([^\/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?/);
//var cmpnts = {
// scheme: parts[2],
// authority: parts[4],
// path: parts[5],
// query: parts[7],
// fragment: parts[9]
//};
//var comp = '';
//if(cmpnts.scheme) { comp += cmpnts.scheme + ':'; }
//if(cmpnts.authority) { comp += '//' + cmpnts.authority; }
// comp += cmpnts.path;
//if(cmpnts.query) { comp += '?' + cmpnts.query; }
//if(cmpnts.fragment) { comp += '#' + cmpnts.fragment; }
//return(null);
return('Invalid data for format uri');
};
return({
"date-time": valDateTime,
"email": valEmail,
"hostname": valHostname,
"ipv4": valIpv4,
"ipv6": valIpv6,
"uri": valUri
});
}
+1
More kB creep, but cleaned-up and without the comments etc it is not that much code.
Could also be an external inclusion, e.g. tv4.standard-formats.js?
Would just be something like:
tv4.addFormat({
'date-time': ...,
'email': ...,
...
});
so people could include it separately (and maybe something automatic for Node, as there are no bandwidth impacts there?).
I have realised that the hostname regex has a bug in that it requires a minimum length of 2 character / label when a 1 character label is acceptable. I think this version is more correct:
^([a-z]|([a-z][0-9a-z-]{0,61}[a-z0-9]))$ (The .toLowerCase() could be replaced by adding A-Z in the regex but I don't know which is preferable.)
In addition this regex only matches an RFC952 hostname, to match RFC1123 it should be adjusted to ^([0-9a-z]|([0-9a-z][0-9a-z-]{0,61}[a-z0-9]))$
http://en.wikipedia.org/wiki/Hostname
I hadn't take into account the code size issue as I'm not delivering this to a browser but I'm happy to take suggestions on how to shrink it.
Note the community created https://www.npmjs.org/package/tv4-formats with some validators like these.