Navigating OAuth2 Authentication with Yahoo DSP: A Comprehensive Guide with Code Examples
Securing and integrating applications with Yahoo's Demand-Side Platform (DSP) APIs necessitates a thorough understanding of OAuth2 authentication. This guide not only walks you through the authentication process but also includes relevant code snippets to ease your journey in generating an access token essential for API access.
Step 1: Generate Your Access Token
The journey to secure API access begins with the generation of an access token, utilizing your client ID and secret. This token is your key to unlocking the extensive features of Yahoo DSP's APIs.
Setting Up Headers for API Access
Incorporate your access token into API requests by adding the following headers:
- X-Auth-Method: Always set to "OAuth2".
- X-Auth-Token: Include the access token generated using your client ID and secret.
Understanding Access Tokens
Yahoo DSP uses the OAuth2 client_credentials workflow, identifying clients through a JSON Web Token (JWT). Although generating this token might seem complex, numerous libraries automate this process for you.
The Anatomy of a JSON Web Token (JWT)
A JWT comprises three components:
1. Header: Indicates the signing algorithm (`HS256`) and token type.
2. Payload: Contains claims and additional data pertinent to Yahoo DSP.
3. Signature: Verifies the token's integrity, created by encoding and signing the header and payload.
Generating a JWT for Yahoo DSP
Here's a step-by-step guide to create your JWT:
1. Header:
```json
{
"alg": "HS256",
"typ": "JWT"
}
```
2. Payload:
```json
{
"aud": "https://id.b2b.yahooinc.com/identity/oauth2/access_token?realm=dsp",
"iss": "<client_id>",
"sub": "<client_id>",
"exp": <Expiry time as Unix Epoch in seconds>,
"iat": <Issued at time as Unix Epoch in seconds>,
"jti": "<UUID>"
}
```
3. Signature:
Generate the signature by encoding the header and payload, then sign it using your client secret.
Code Example: Generating JWT Signature
static async Task GetToken()
{
string clientId = "clientId ";
string clientSecret = "clientSecret ";
string aud = "https://id.b2b.yahooinc.com/identity/oauth2/access_token?realm=dsp";
long exp = (long)(DateTime.UtcNow.AddHours(1) - new DateTime(1970, 1, 1)).TotalSeconds; // Expiry time in Unix Epoch in seconds (1 hour from now)
long iat = (long)(DateTime.UtcNow - new DateTime(1970, 1, 1)).TotalSeconds; // Issued at time in Unix Epoch in seconds
string jti = Guid.NewGuid().ToString(); // Unique identifier for the JWT
// Create JWT payload
var payload = new
{
aud = aud,
iss = clientId,
sub = clientId,
exp = exp,
iat = iat,
jti = jti
};
// Convert payload to JSON
string payloadJson = JsonConvert.SerializeObject(payload);
// Base64 URL encode the payload
string base64Payload = Base64UrlEncode(Encoding.UTF8.GetBytes(payloadJson));
// Create JWT header
var header = new
{
alg = "HS256",
typ = "jwt"
};
// Convert header to JSON
string headerJson = JsonConvert.SerializeObject(header);
// Base64 URL encode the header
string base64Header = Base64UrlEncode(Encoding.UTF8.GetBytes(headerJson));
// Concatenate header and payload
string jwtSigningString = base64Header + "." + base64Payload;
// Create signature using HMAC-SHA256
byte[] key = Encoding.UTF8.GetBytes(clientSecret);
byte[] signatureBytes = HmacSha256(jwtSigningString, key);
string signature = Base64UrlEncode(signatureBytes);
// Create final JWT
string jwt = jwtSigningString + "." + signature;
Console.WriteLine(jwt);
}
static byte[] HmacSha256(string message, byte[] key)
{
using (var hmac = new HMACSHA256(key))
{
return hmac.ComputeHash(Encoding.UTF8.GetBytes(message));
}
}
static string Base64UrlEncode(byte[] input)
{
return Convert.ToBase64String(input)
.Replace('+', '-')
.Replace('/', '_')
.Replace("=", "");
}
Using the JWT to Obtain an Access Token
With your JWT ready, request an access token from Yahoo DSP. Here's a sample `postman` to guide you:
Sample Postman
Accessing Yahoo Protected API
Finally, with your access token, you can dive into Yahoo DSP's APIs. Remember to include your token in the `Authorization` header for authentication.
This comprehensive guide, equipped with code examples, demystifies the OAuth2 authentication process for Yahoo DSP, ensuring you can securely and effectively access its APIs. With these tools at your disposal, your applications can harness the full power of Yahoo DSP's capabilities, driving your digital advertising strategies forward.
Comments
Post a Comment