Amazon Selling Partner API Models

Use DownloadHelper to download encrypted documents and read their decrypted contents. The process returns a DownloadBundle which can be used to access the decrypted data stream.

Key components:

• DownloadHelper: The main class for performing downloads.
• DownloadSpecification: Defines the download parameters including the AESCryptoStreamFactory and the document url. You can also specify a CompressionAlgorithm using .withCompressionAlgorithm().
• DownloadBundle: An object returned by download() that implements AutoCloseable. It provides methods like newBufferedReader() to read the decrypted content.
• CompressionAlgorithm: Use CompressionAlgorithm.fromEquivalent(string) to map a string representation to the required algorithm.

import com.amazon.spapi.documents.DownloadHelper;
import com.amazon.spapi.documents.DownloadSpecification;
import com.amazon.spapi.documents.DownloadBundle;
import com.amazon.spapi.documents.CompressionAlgorithm;
import com.amazon.spapi.documents.impl.AESCryptoStreamFactory;
import java.io.BufferedReader;

public void downloadAndDecrypt(String key, String initializationVector, String url, String compressionAlgorithm) {
    AESCryptoStreamFactory aesCryptoStreamFactory = 
            new AESCryptoStreamFactory.Builder(key, initializationVector).build();

    DownloadSpecification downloadSpec = new DownloadSpecification.Builder(aesCryptoStreamFactory, url)
            .withCompressionAlgorithm(CompressionAlgorithm.fromEquivalent(compressionAlgorithm))
            .build();

    DownloadHelper downloadHelper = new DownloadHelper.Builder().build();

    try (DownloadBundle downloadBundle = downloadHelper.download(downloadSpec)) {
        try (BufferedReader reader = downloadBundle.newBufferedReader()) {
            String line;
            while ((line = reader.readLine()) != null) {
                // Process the decrypted line
            }
        }
    } catch (Exception e) {
        // Handle CryptoException, HttpResponseException, IOException, or MissingCharsetException
    }
}

The LWAAuthorizationSigner class handles obtaining and signing HTTP requests with an access token from Login with Amazon (LWA) for a specific endpoint. It is designed to work with Selling Partner API Client Libraries generated via openapi-generator using Guzzle.

To use it, provide LWAAuthorizationCredentials containing your clientId, clientSecret, refreshToken, and the LWA endpoint. You then initialize the signer and pass the configuration to your generated API client.

$lwaAuthorizationCredentials = new LWAAuthorizationCredentials([
"clientId" => '.....',
"clientSecret" => '.....',
"refreshToken" => '.....',
"endpoint" => 'https://api.amazon.com/auth/o2/token'
]);

// Initialize LWAAuthorizationSigner instance
$lwaAuthorizationSigner = new LWAAuthorizationSigner($lwaAuthorizationCredentials);
$config = new Configuration([], $lwaAuthorizationCredentials);

// Setting SP-API endpoint region. Change it according to the desired region
$config->setHost('https://sellingpartnerapi-na.amazon.com');

// Create a new HTTP client
$client = new GuzzleHttp\Client();

// Create an instance of the Orders Api client
$api = new OrdersApi($config, null, $client);

The Merchant Fulfillment V0 API causes a fatal error during SDK generation. To fix this, you must manually modify the model file before running the generation script.

1. Download the models using ./generate-js-sdk.sh.
2. Locate the file: <package root>/models/merchant-fulfillment-api-model/merchantFulfillmentV0.json.
3. Find this block:

"AvailableFormatOptionsForLabel": {
      "$ref": "#/definitions/AvailableFormatOptionsForLabelList"
},

4. Replace it with this snippet:

"AvailableFormatOptionsForLabel": {
    "type": "array",
    "description": "The available label formats.",
    "items": {
        "$ref": "#/definitions/LabelFormatOption"
    }
},

5. Run the generation script again:

$ ./generate-js-sdk.sh -j <path/to/swagger-codegen-cli-2.4.29.jar>

Important: When prompted Found <package root>/models already exists. Would you like to delete all the files under '<package root>/models' and clone again? [y/n]:, answer n. Answering y will overwrite your manual fix.