Spaces:
Sleeping
Sleeping
File size: 12,789 Bytes
05a77ff |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 |
/**
* Specification: http://www.w3.org/TR/2012/WD-cors-20120403/
* W3C Working Draft 3 April 2012
*/
"use strict";
/*jshint node:true */
var simpleMethods, simpleRequestHeaders, simpleResponseHeaders, toLowerCase, checkOriginMatch;
// A method is said to be a simple method if it is a case-sensitive match for one of the following:
Object.defineProperty(exports, "simpleMethods", {
get: function () {
return [
"GET",
"HEAD",
"POST"
];
}
});
simpleMethods = exports.simpleMethods;
// A header is said to be a simple header if the header field name is an ASCII case-insensitive match for one of
// the following:
Object.defineProperty(exports, "simpleRequestHeaders", {
get: function () {
return [
"accept",
"accept-language",
"content-language",
"content-type"
];
}
});
simpleRequestHeaders = exports.simpleRequestHeaders;
// A header is said to be a simple response header if the header field name is an ASCII case-insensitive
// match for one of the following:
Object.defineProperty(exports, "simpleResponseHeaders", {
get: function () {
return [
"cache-control",
"content-language",
"content-type",
"expires",
"last-modified",
"pragma"
];
}
});
simpleResponseHeaders = exports.simpleResponseHeaders;
toLowerCase = function (array) {
return array.map(function (el) {
return el.toLowerCase();
});
};
checkOriginMatch = function (originHeader, origins, callback) {
if (typeof origins === "function") {
origins(originHeader, function (err, allow) {
callback(err, allow);
});
} else if (origins.length > 0) {
callback(null, origins.some(function (origin) {
return origin === originHeader;
}));
} else {
// Always matching is acceptable since the list of origins can be unbounded.
callback(null, true);
}
};
exports.create = function (options) {
options = options || {};
options.origins = options.origins || [];
options.methods = options.methods || simpleMethods;
if (options.hasOwnProperty("requestHeaders") === true) {
options.requestHeaders = toLowerCase(options.requestHeaders);
} else {
options.requestHeaders = simpleRequestHeaders;
}
if (options.hasOwnProperty("responseHeaders") === true) {
options.responseHeaders = toLowerCase(options.responseHeaders);
} else {
options.responseHeaders = simpleResponseHeaders;
}
options.maxAge = options.maxAge || null;
options.supportsCredentials = options.supportsCredentials || false;
if (options.hasOwnProperty("endPreflightRequests") === false) {
options.endPreflightRequests = true;
}
return function (req, res, next) {
var methodMatches, headersMatch, requestMethod, requestHeaders, exposedHeaders, endPreflight;
// If the Origin header is not present terminate this set of steps.
if (!req.headers.hasOwnProperty("origin")) {
// The request is outside the scope of the CORS specification. If there is no Origin header,
// it could be a same-origin request. Let's let the user-agent handle this situation.
next();
} else {
// If the value of the Origin header is not a case-sensitive match for any of the values in
// list of origins, do not set any additional headers and terminate this set of steps.
checkOriginMatch(req.headers.origin, options.origins, function (err, originMatches) {
if (err !== null) {
next(err);
} else {
if (typeof originMatches !== "boolean" || originMatches === false) {
next();
} else {
// Respond to preflight request.
if (req.method === "OPTIONS") {
endPreflight = function () {
if (options.endPreflightRequests === true) {
res.writeHead(204);
res.end();
} else {
next();
}
};
// If there is no Access-Control-Request-Method header or if parsing failed, do not set
// any additional headers and terminate this set of steps.
if (!req.headers.hasOwnProperty("access-control-request-method")) {
endPreflight();
} else {
requestMethod = req.headers["access-control-request-method"];
// If there are no Access-Control-Request-Headers headers let header field-names be the
// empty list. If parsing failed do not set any additional headers and terminate this set
// of steps.
// Checking for an empty header is a workaround for a bug Chrome 52:
// https://bugs.chromium.org/p/chromium/issues/detail?id=633729
if (req.headers.hasOwnProperty("access-control-request-headers") && req.headers["access-control-request-headers"] !== "") {
requestHeaders = toLowerCase(req.headers["access-control-request-headers"].split(/,\s*/));
} else {
requestHeaders = [];
}
// If method is not a case-sensitive match for any of the values in list of methods do not
// set any additional headers and terminate this set of steps.
methodMatches = options.methods.indexOf(requestMethod) !== -1;
if (methodMatches === false) {
endPreflight();
} else {
// If any of the header field-names is not a ASCII case-insensitive match for any of
// the values in list of headers do not set any additional headers and terminate this
// set of steps.
headersMatch = requestHeaders.every(function (requestHeader) {
// Browsers automatically add Origin to Access-Control-Request-Headers. However,
// Origin is not one of the simple request headers. Therefore, the header is
// accepted even if it is not in the list of request headers because CORS would
// not work without it.
if (requestHeader === "origin") {
return true;
} else {
if (options.requestHeaders.indexOf(requestHeader) !== -1) {
return true;
} else {
return false;
}
}
});
if (headersMatch === false) {
endPreflight();
} else {
if (options.supportsCredentials === true) {
// If the resource supports credentials add a single Access-Control-Allow-Origin
// header, with the value of the Origin header as value, and add a single
// Access-Control-Allow-Credentials header with the literal string "true"
// as value.
res.setHeader("Access-Control-Allow-Origin", req.headers.origin);
res.setHeader("Access-Control-Allow-Credentials", "true");
} else {
// Otherwise, add a single Access-Control-Allow-Origin header, with either the
// value of the Origin header or the string "*" as value.
if (options.origins.length > 0 || typeof options.origins === "function") {
res.setHeader("Access-Control-Allow-Origin", req.headers.origin);
} else {
res.setHeader("Access-Control-Allow-Origin", "*");
}
}
// Optionally add a single Access-Control-Max-Age header with as value the amount
// of seconds the user agent is allowed to cache the result of the request.
if (options.maxAge !== null) {
res.setHeader("Access-Control-Max-Age", options.maxAge);
}
// Add one or more Access-Control-Allow-Methods headers consisting of (a subset
// of) the list of methods.
res.setHeader("Access-Control-Allow-Methods", options.methods.join(","));
// Add one or more Access-Control-Allow-Headers headers consisting of (a subset
// of) the list of headers.
res.setHeader("Access-Control-Allow-Headers", options.requestHeaders.join(","));
// And out.
endPreflight();
}
}
}
} else {
if (options.supportsCredentials === true) {
// If the resource supports credentials add a single Access-Control-Allow-Origin header,
// with the value of the Origin header as value, and add a single
// Access-Control-Allow-Credentials header with the literal string "true" as value.
res.setHeader("Access-Control-Allow-Origin", req.headers.origin);
res.setHeader("Access-Control-Allow-Credentials", "true");
} else {
// Otherwise, add a single Access-Control-Allow-Origin header, with either the value of
// the Origin header or the literal string "*" as value.
// If the list of origins is empty, use "*" as value.
if (options.origins.length > 0 || typeof options.origins === "function") {
res.setHeader("Access-Control-Allow-Origin", req.headers.origin);
} else {
res.setHeader("Access-Control-Allow-Origin", "*");
}
}
// If the list of exposed headers is not empty add one or more Access-Control-Expose-Headers
// headers, with as values the header field names given in the list of exposed headers.
exposedHeaders = options.responseHeaders.filter(function (optionsResponseHeader) {
return simpleResponseHeaders.indexOf(optionsResponseHeader) === -1;
});
if (exposedHeaders.length > 0) {
res.setHeader("Access-Control-Expose-Headers", exposedHeaders.join(","));
}
// And out.
next();
}
}
}
});
}
};
};
|