Backend half

SerpentRace_Backend/node_modules/aws-sdk/lib/signers/v4_credentials.js

@@ -0,0 +1,100 @@
+var AWS = require('../core');
+
+/**
+ * @api private
+ */
+var cachedSecret = {};
+
+/**
+ * @api private
+ */
+var cacheQueue = [];
+
+/**
+ * @api private
+ */
+var maxCacheEntries = 50;
+
+/**
+ * @api private
+ */
+var v4Identifier = 'aws4_request';
+
+/**
+ * @api private
+ */
+module.exports = {
+  /**
+   * @api private
+   *
+   * @param date [String]
+   * @param region [String]
+   * @param serviceName [String]
+   * @return [String]
+   */
+  createScope: function createScope(date, region, serviceName) {
+    return [
+      date.substr(0, 8),
+      region,
+      serviceName,
+      v4Identifier
+    ].join('/');
+  },
+
+  /**
+   * @api private
+   *
+   * @param credentials [Credentials]
+   * @param date [String]
+   * @param region [String]
+   * @param service [String]
+   * @param shouldCache [Boolean]
+   * @return [String]
+   */
+  getSigningKey: function getSigningKey(
+    credentials,
+    date,
+    region,
+    service,
+    shouldCache
+  ) {
+    var credsIdentifier = AWS.util.crypto
+      .hmac(credentials.secretAccessKey, credentials.accessKeyId, 'base64');
+    var cacheKey = [credsIdentifier, date, region, service].join('_');
+    shouldCache = shouldCache !== false;
+    if (shouldCache && (cacheKey in cachedSecret)) {
+      return cachedSecret[cacheKey];
+    }
+
+    var kDate = AWS.util.crypto.hmac(
+      'AWS4' + credentials.secretAccessKey,
+      date,
+      'buffer'
+    );
+    var kRegion = AWS.util.crypto.hmac(kDate, region, 'buffer');
+    var kService = AWS.util.crypto.hmac(kRegion, service, 'buffer');
+
+    var signingKey = AWS.util.crypto.hmac(kService, v4Identifier, 'buffer');
+    if (shouldCache) {
+      cachedSecret[cacheKey] = signingKey;
+      cacheQueue.push(cacheKey);
+      if (cacheQueue.length > maxCacheEntries) {
+        // remove the oldest entry (not the least recently used)
+        delete cachedSecret[cacheQueue.shift()];
+      }
+    }
+
+    return signingKey;
+  },
+
+  /**
+   * @api private
+   *
+   * Empties the derived signing key cache. Made available for testing purposes
+   * only.
+   */
+  emptyCache: function emptyCache() {
+    cachedSecret = {};
+    cacheQueue = [];
+  }
+};