Backend half

SerpentRace_Backend/node_modules/aws-sdk/lib/signers/presign.js

@@ -0,0 +1,119 @@
+var AWS = require('../core');
+var inherit = AWS.util.inherit;
+
+/**
+ * @api private
+ */
+var expiresHeader = 'presigned-expires';
+
+/**
+ * @api private
+ */
+function signedUrlBuilder(request) {
+  var expires = request.httpRequest.headers[expiresHeader];
+  var signerClass = request.service.getSignerClass(request);
+
+  delete request.httpRequest.headers['User-Agent'];
+  delete request.httpRequest.headers['X-Amz-User-Agent'];
+
+  if (signerClass === AWS.Signers.V4) {
+    if (expires > 604800) { // one week expiry is invalid
+      var message = 'Presigning does not support expiry time greater ' +
+                    'than a week with SigV4 signing.';
+      throw AWS.util.error(new Error(), {
+        code: 'InvalidExpiryTime', message: message, retryable: false
+      });
+    }
+    request.httpRequest.headers[expiresHeader] = expires;
+  } else if (signerClass === AWS.Signers.S3) {
+    var now = request.service ? request.service.getSkewCorrectedDate() : AWS.util.date.getDate();
+    request.httpRequest.headers[expiresHeader] = parseInt(
+      AWS.util.date.unixTimestamp(now) + expires, 10).toString();
+  } else {
+    throw AWS.util.error(new Error(), {
+      message: 'Presigning only supports S3 or SigV4 signing.',
+      code: 'UnsupportedSigner', retryable: false
+    });
+  }
+}
+
+/**
+ * @api private
+ */
+function signedUrlSigner(request) {
+  var endpoint = request.httpRequest.endpoint;
+  var parsedUrl = AWS.util.urlParse(request.httpRequest.path);
+  var queryParams = {};
+
+  if (parsedUrl.search) {
+    queryParams = AWS.util.queryStringParse(parsedUrl.search.substr(1));
+  }
+
+  var auth = request.httpRequest.headers['Authorization'].split(' ');
+  if (auth[0] === 'AWS') {
+    auth = auth[1].split(':');
+    queryParams['Signature'] = auth.pop();
+    queryParams['AWSAccessKeyId'] = auth.join(':');
+
+    AWS.util.each(request.httpRequest.headers, function (key, value) {
+      if (key === expiresHeader) key = 'Expires';
+      if (key.indexOf('x-amz-meta-') === 0) {
+        // Delete existing, potentially not normalized key
+        delete queryParams[key];
+        key = key.toLowerCase();
+      }
+      queryParams[key] = value;
+    });
+    delete request.httpRequest.headers[expiresHeader];
+    delete queryParams['Authorization'];
+    delete queryParams['Host'];
+  } else if (auth[0] === 'AWS4-HMAC-SHA256') { // SigV4 signing
+    auth.shift();
+    var rest = auth.join(' ');
+    var signature = rest.match(/Signature=(.*?)(?:,|\s|\r?\n|$)/)[1];
+    queryParams['X-Amz-Signature'] = signature;
+    delete queryParams['Expires'];
+  }
+
+  // build URL
+  endpoint.pathname = parsedUrl.pathname;
+  endpoint.search = AWS.util.queryParamsToString(queryParams);
+}
+
+/**
+ * @api private
+ */
+AWS.Signers.Presign = inherit({
+  /**
+   * @api private
+   */
+  sign: function sign(request, expireTime, callback) {
+    request.httpRequest.headers[expiresHeader] = expireTime || 3600;
+    request.on('build', signedUrlBuilder);
+    request.on('sign', signedUrlSigner);
+    request.removeListener('afterBuild',
+      AWS.EventListeners.Core.SET_CONTENT_LENGTH);
+    request.removeListener('afterBuild',
+      AWS.EventListeners.Core.COMPUTE_SHA256);
+
+    request.emit('beforePresign', [request]);
+
+    if (callback) {
+      request.build(function() {
+        if (this.response.error) callback(this.response.error);
+        else {
+          callback(null, AWS.util.urlFormat(request.httpRequest.endpoint));
+        }
+      });
+    } else {
+      request.build();
+      if (request.response.error) throw request.response.error;
+      return AWS.util.urlFormat(request.httpRequest.endpoint);
+    }
+  }
+});
+
+/**
+ * @api private
+ */
+module.exports = AWS.Signers.Presign;