...
Before sending the request, the client will add a timestamp to the data in the request, so now the request will be something like:
| Code Block |
|---|
GET /esapis/v1.0/classlist?term=2015SP&subject=8.011×tamp=20140715113137 |
Then (also before the request is sent) to derive the hash value, the client will:
...
| Code Block |
|---|
import urllib2
import json
import hashlib
import datetime
# The base URL:
urlBase="https://mv-ezproxy-com.ezproxyberklee.flo.org/esapis/v1.0/classlist?term=2015SP&subject=8.011"
# For authentication, as well as the base query parameters (term and subject),
# the URL must include these additional query parameters:
# user, timestamp, hash
#
# Form the hash variable (SHA-256 hash of base parameter values + timestamp + shared secret).
user = "gravytrain"
secret = "September"
timeStamp = datetime.datetime.today().strftime('%Y%m%d%H%M%S')
toBeHashed = "2015SP" + "8.011" + timeStamp + secret
hashObj = hashlib.sha256(toBeHashed.encode())
# Complete the URL string by adding the additional parameters (timestamp, user, and hash):
url = urlBase + "×tamp=" + timeStamp + "&user=" + user + "&hash=" + hashObj.hexdigest()
# Get the data from the API in JSON form.
result = json.load(urllib2.urlopen(url))
|
Some Other Languages/Environments
Other languages provide similar capability for generating SHA256 hash values. All the examples are generating hashes for a string with value "some value".
Java:
| Code Block | ||
|---|---|---|
| ||
import java.security.MessageDigest;
...
String textToBeHashed = "some value";
MessageDigest digest = MessageDigest.getInstance(args[1]);
byte[] hash = digest.digest(textToBeHashed.getBytes("UTF-8"));
StringBuffer hexString = new StringBuffer();
for (int i = 0; i < hash.length; i++) {
String hex = Integer.toHexString(0xff & hash[i]);
if(hex.length() == 1) hexString.append('0');
hexString.append(hex);
} |
Bash Shell Command Line:
| Code Block | ||
|---|---|---|
| ||
echo -n "some value"|sha256sum |
Javascript:
| Code Block | ||
|---|---|---|
| ||
<script type="text/javascript" src="sjcl.min.js" ></script>
<script language="JavaScript" type="text/javascript">
var bitArray = sjcl.hash.sha256.hash("some value");
var hash = sjcl.codec.hex.fromBits(bitArray);
</script> |