This Node.js function is designed to retrieve data from Analytics:
function getDataFromGA(Dimension, Metric, StartDate, EndDate, MaxResults) {
var fs = require('fs'),
crypto = require('crypto'),
request = require('request'); // This module is external
var authHeader = {
'alg': 'RS256',
'typ': 'JWT'
},
authClaimSet = {
'iss': '***<a href="/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="b0c4f0d4d5c6d5dcdfc0d5c29ed7c3d5c2c6d9d3d5d1d3d3dfc5dec49ed3dfdd">[email protected]</a>', // Service account email
'scope': 'https://www.googleapis.com/auth/analytics.readonly',
// Only want to read data
'aud': 'https://accounts.google.com/o/oauth2/token'
},
SIGNATURE_ALGORITHM = '**',
SIGNATURE_ENCODE_METHOD = '**',
GA_KEY_PATH = '**',
//appends private key to the directory
gaKey;
function urlEscape(source) {
return source.replace(/\+/g, '-').replace(/\//g, '_').replace(/\=+$/, '');
}
function base64Encode(obj) {
var encoded = new Buffer(JSON.stringify(obj), 'utf8').toString('base64');
return urlEscape(encoded);
}
function readPrivateKey() {
if (!gaKey) {
gaKey = fs.readFileSync(GA_KEY_PATH, 'utf8');
}
return gaKey;
}
var authorize = function (callback) {
var self = this,
now = parseInt(Date.now() / 1000, 10), // Google prefers seconds
cipher,
signatureInput,
signatureKey = readPrivateKey(),
signature,
jwt;
// Setup time values
authClaimSet.iat = now;
authClaimSet.exp = now + 60; // Token valid for one minute
// Setup JWT source
signatureInput = base64Encode(authHeader) + '.' + base64Encode(authClaimSet);
// Generate JWT
cipher = crypto.createSign('RSA-SHA256');
cipher.update(signatureInput);
signature = cipher.sign(signatureKey, 'base64');
jwt = signatureInput + '.' + urlEscape(signature);
// Send request to authorize this application
request({
method: 'POST',
headers: {
'Content-Type': 'application/x-www-form-urlencoded'
},
uri: 'https://accounts.google.com/o/oauth2/token',
body: 'grant_type=' + escape('urn:ietf:params:oauth:grant-type:jwt-bearer') +
'&assertion=' + jwt
}, function (error, response, body) {
if (error) {
console.log(error);
callback(new Error(error));
} else {
var gaResult = JSON.parse(body);
if (gaResult.error) {
callback(new Error(gaResult.error));
} else {
callback(null, gaResult.access_token);
// console.log(gaResult);
console.log("Authorized");
}
}
});
};
var request = require('request'),
qs = require('querystring');
authorize(function (err, token) {
if (!err) {
// Retrieve total visits for a month
var requestConfig = {
'ids': 'ga:72333024',
'dimensions': Dimension,
'metrics': Metric,
// 'sort': '-ga:users',
'start-date': StartDate,
'end-date': EndDate,
'max-results': MaxResults
};
request({
method: 'GET',
headers: {
'Authorization': 'Bearer ' + token // Use the auth token here
},
uri: 'https://www.googleapis.com/analytics/v3/data/ga?' + qs.stringify(requestConfig)
}, function (error, resp, body) {
console.log(body);
var data = JSON.parse(body);
console.log(data.totalsForAllResults);
console.log(data.rows);
});
}
});
}
Attempting to access it externally:
var gaJSON = utils.getDataFromGA("ga:country", "ga:pageviews", "2011-08-04", "2014-09-12", "50");
res.send(gaJSON);
Questioning how to access the data variable at the end of the first method and call it externally.