byQLp3wM

1/**
2 * JavaScript based IAM Authorization for Neptune
3 * protocol WebSocket
4 *
5 * v3 (support for EC2 IAM Roles)
6 * by lior@amazon.com
7 *
8 * IAM Authentication:
9 * See https://docs.aws.amazon.com/sdk-for-javascript/v2/developer-guide/setting-credentials-node.html
10 * Here are the ways you can supply your credentials in order of recommendation:
11 * Loaded from AWS Identity and Access Management (IAM) roles for Amazon EC2 (if running on Amazon EC2)
12 * Loaded from the shared credentials file (~/.aws/credentials) preferrably with a dedicated profile.
13 * Loaded from environment variables
14 *
15 **/
16
17var crypto = require('crypto-js');
18const gremlin = require('gremlin');
19var AWS = require('aws-sdk');
20
21function isUndefined(value) {
22  return typeof value === 'undefined' || value === null;
23};
24
25function makeTwoDigits(n) {
26  if (n > 9) {
27    return n;
28  } else {
29    return '0' + n;
30  }
31}
32
33function getDateTimeString() {
34  var d = new Date();
35
36  //
37  // The additional ''s are used to force JavaScript to interpret the
38  // '+' operator as string concatenation rather than arithmetic.
39  //
40  return d.getUTCFullYear() + '' +
41    makeTwoDigits(d.getUTCMonth() + 1) + '' +
42    makeTwoDigits(d.getUTCDate()) + 'T' + '' +
43    makeTwoDigits(d.getUTCHours()) + '' +
44    makeTwoDigits(d.getUTCMinutes()) + '' +
45    makeTwoDigits(d.getUTCSeconds()) + 'Z';
46}
47
48function getDateString(dateTimeString) {
49  return dateTimeString.substring(0, dateTimeString.indexOf('T'));
50}
51
52function getSignatureKey(key, dateStamp, regionName, serviceName) {
53  var kDate = crypto.HmacSHA256(dateStamp, 'AWS4' + key, {
54    asBytes: true
55  });
56  var kRegion = crypto.HmacSHA256(regionName, kDate, {
57    asBytes: true
58  });
59  var kService = crypto.HmacSHA256(serviceName, kRegion, {
60    asBytes: true
61  });
62  var kSigning = crypto.HmacSHA256('aws4_request', kService, {
63    asBytes: true
64  });
65  return kSigning;
66}
67
68function getSignature(method, scheme, hostname, port, path, accessId, secretKey,
69  region, serviceName, payload, canonicalQueryString, today, datetimeStamp, debug) {
70
71  var canonicalHeaders = 'host:' + hostname.toLowerCase() + ':' + port + '\n' + 'x-amz-date:' + datetimeStamp + '\n';
72  var signedHeaders = 'host;x-amz-date';
73
74  var canonicalRequest = method + '\n' + // method
75    path + '\n' + // path
76    canonicalQueryString + '\n' + // query params
77    canonicalHeaders + // headers
78    '\n' + // required
79    signedHeaders + '\n' + // signed header list
80    crypto.SHA256(payload, {
81      asBytes: true
82    }); // hash of payload (empty string)
83
84  if (debug === true) {
85    console.log('Canonical request: ' + ' \n ' + canonicalRequest.replace(/(\r\n\t|\n|\r\t)/gm," \n ") + '\n');
86  }
87
88  var hashedCanonicalRequest = crypto.SHA256(canonicalRequest, {
89    asBytes: true
90  });
91
92  if (debug === true) {
93    console.log('Hashed canonical request: ' + hashedCanonicalRequest + '\n');
94  }
95
96  var stringToSign = 'AWS4-HMAC-SHA256\n' +
97    datetimeStamp + '\n' +
98    today + '/' + region + '/' + serviceName + '/aws4_request\n' +
99    hashedCanonicalRequest;
100
101  if (debug === true) {
102    console.log('String to sign: ' + ' \n ' + stringToSign.replace(/(\r\n\t|\n|\r\t)/gm," \n ") + '\n');
103  }
104
105  var signingKey = getSignatureKey(secretKey, today, region, serviceName);
106
107  if (debug === true) {
108    console.log('Signing key: ' + signingKey + '\n');
109  }
110
111  var signature = crypto.HmacSHA256(stringToSign, signingKey, {
112    asBytes: true
113  });
114
115  if (debug === true) {
116    console.log('Signature: ' + signature + '\n');
117  }
118
119  return signature;
120}
121
122function getAuthHeader(options, awsAccessId, awsSecretKey, datetimeStamp) {
123  var today = getDateString(datetimeStamp);
124  var signature = getSignature(options.method, options.scheme, options.hostname, options.port, options.path,
125    awsAccessId, awsSecretKey, options.region, options.serviceName, options.payload, options.canonicalQueryString,
126    today, datetimeStamp, options.debug)
127
128  return 'AWS4-HMAC-SHA256 ' +
129    'Credential=' + awsAccessId + '/' + today + '/' + options.region + '/' + options.serviceName + '/aws4_request,' +
130    'SignedHeaders=host;x-amz-date,' +
131    'Signature=' + signature;
132}
133
134AWS.config.getCredentials(Main);
135
136function Main(err) {
137
138  /// Main logic
139
140  if (err) {
141    console.log('Could not load credentials...');
142    throw err;
143  };
144
145  var datetimeStamp = getDateTimeString();
146  var creds = AWS.config.credentials
147
148  //TODO change hostname, region.
149  var options = {
150    method: 'GET',
151    scheme: 'ws://',
152    hostname: 'your.neptune-endpoint.eu-west-1.neptune.amazonaws.com', //either cluster or instance
153    port: 8182,
154    path: '/gremlin',
155    method: 'GET',
156    payload: '', // empty string for HTTP GET
157    canonicalQueryString: '', // empty string for websocket
158    debug: true, // enable verbose output for signature process.
159    region: 'eu-west-1',
160    serviceName: 'neptune-db'
161  };
162
163  //Setup Headers for Authorization
164  if (options.debug === true) {
165    console.log("\x1b[44m%s\x1b[0m", 'Credential source: ' + creds.constructor.name, '\n');
166  };
167
168  var awsheaders = {};
169  awsheaders['Authorization'] = getAuthHeader(options, creds.accessKeyId, creds.secretAccessKey, datetimeStamp);
170  awsheaders['x-amz-date'] = datetimeStamp;
171  if (!isUndefined(AWS.config.credentials.sessionToken)) {
172    awsheaders['X-Amz-Security-Token'] = creds.sessionToken
173  };
174
175  if (options.debug === true) {
176    console.log('Final HTTP headers: ' + JSON.stringify(awsheaders, null, 2) + '\n');
177  };
178
179  //Build the URL
180  var url = options.scheme + options.hostname + ':' + options.port + options.path
181  if (options.debug === true) {
182    console.log('URL to send: ' + url + '\n');
183  };
184
185  //Connect with Gremlin
186  const DriverRemoteConnection = gremlin.driver.DriverRemoteConnection;
187  const Graph = gremlin.structure.Graph;
188  dc = new DriverRemoteConnection(url, {
189    headers: awsheaders
190  });
191
192  // Use Gremlin
193  const graph = new Graph();
194  const g = graph.traversal().withRemote(dc);
195
196  g.V().limit(1).count().next().
197  then(data => {
198    console.log(data);
199    dc.close();
200  }).catch(error => {
201    console.log('ERROR', error);
202    dc.close();
203  });
204}