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Menghubungkan ke database Amazon Neptune menggunakan otentikasi IAM dengan SPARQL dan Node.js

Kueri menggunakan penandatanganan Signature V4 dan AWS SDK para Javascript V3

Berikut adalah contoh cara menyambung ke Neptune SPARQL menggunakan Node.js otentikasi Signature Versi 4 dan AWS SDK untuk Javascript V3:

const { HttpRequest }  = require('@smithy/protocol-http');
const { fromNodeProviderChain } = require('@aws-sdk/credential-providers');
const { SignatureV4 } = require('@smithy/signature-v4');
const { Sha256 } = require('@aws-crypto/sha256-universal');
const https = require('https');

var region = 'us-west-2'; // e.g. us-west-1
var neptune_endpoint = 'your-Neptune-cluster-endpoint';  // like: 'cluster-id.region.neptune.amazonaws.com'
var query = `query=PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX class: <http://aws.amazon.com/neptune/csv2rdf/class/>
PREFIX resource: <http://aws.amazon.com/neptune/csv2rdf/resource/>
PREFIX prop: <http://aws.amazon.com/neptune/csv2rdf/datatypeProperty/>
PREFIX objprop: <http://aws.amazon.com/neptune/csv2rdf/objectProperty/>

SELECT ?movies ?title WHERE {
  ?jel prop:name "James Earl Jones" .
  ?movies ?p2 ?jel .
  ?movies prop:title ?title
} LIMIT 10`;

runQuery(query);

function runQuery(q) {
  var request = new HttpRequest({
    hostname: neptune_endpoint,
    port: 8182,
    path: 'sparql',
    body: encodeURI(query),
    headers: {
      'Content-Type': 'application/x-www-form-urlencoded',
      'host': neptune_endpoint + ':8182',
    },
    method: 'POST',
  });

  const credentialProvider = fromNodeProviderChain();
  let credentials = credentialProvider();
  credentials.then(
    (cred)=>{
      var signer = new SignatureV4({credentials: cred, region: region, sha256: Sha256, service: 'neptune-db'});
      signer.sign(request).then(
        (req)=>{
          var responseBody = '';
          var sendreq = https.request(
            {
              host: req.hostname,
              port: req.port,
              path: req.path,
              method: req.method,
              headers: req.headers,
            },
          (res) => {
            res.on('data', (chunk) => { responseBody += chunk; });
            res.on('end', () => {
                console.log(JSON.parse(responseBody));
            });
          });
          sendreq.write(req.body);
          sendreq.end();
        }
      );
    },
    (err)=>{
      console.error(err);
    }
  );
}

Kueri menggunakan penandatanganan Signature V4 dan AWS SDK para Javascript V2

Berikut adalah contoh cara menyambung ke Neptune SPARQL menggunakan Node.js otentikasi Signature Versi 4 dan AWS SDK untuk Javascript V2:

var AWS = require('aws-sdk');

var region = 'us-west-2'; // e.g. us-west-1
var neptune_endpoint = 'your-Neptune-cluster-endpoint';  // like: 'cluster-id.region.neptune.amazonaws.com'
var query = `query=PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX class: <http://aws.amazon.com/neptune/csv2rdf/class/>
PREFIX resource: <http://aws.amazon.com/neptune/csv2rdf/resource/>
PREFIX prop: <http://aws.amazon.com/neptune/csv2rdf/datatypeProperty/>
PREFIX objprop: <http://aws.amazon.com/neptune/csv2rdf/objectProperty/>

SELECT ?movies ?title WHERE {
    ?jel prop:name "James Earl Jones" .
    ?movies ?p2 ?jel .
    ?movies prop:title ?title
} LIMIT 10`;

runQuery(query);

function runQuery(q) {

    var endpoint = new AWS.Endpoint(neptune_endpoint);
    endpoint.port = 8182;
    var request = new AWS.HttpRequest(endpoint, region);
    request.path += 'sparql';
    request.body = encodeURI(query);
    request.headers['Content-Type'] = 'application/x-www-form-urlencoded';
    request.headers['host'] = neptune_endpoint;
    request.method = 'POST';

    var credentials = new AWS.CredentialProviderChain();
    credentials.resolve((err, cred)=>{
        var signer = new AWS.Signers.V4(request, 'neptune-db');
        signer.addAuthorization(cred, new Date());
    });

    var client = new AWS.HttpClient();
    client.handleRequest(request, null, function(response) {
        console.log(response.statusCode + ' ' + response.statusMessage);
        var responseBody = '';
        response.on('data', function (chunk) {
            responseBody += chunk;
        });
        response.on('end', function (chunk) {
            console.log('Response body: ' + responseBody);
        });
    }, function(error) {
        console.log('Error: ' + error);
    });
}