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Dart Requires Chilkat v11.0.0+

Amazon Pay - Create Checkout Session

See more Amazon Pay Examples

Create a new Amazon Pay Checkout Session.

Chilkat Dart Downloads

Dart
import 'package:chilkat/chilkat.dart';

void main() {
  // This example assumes the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  final http = CkHttp();

  // Implements the following CURL command:

  // curl "https://pay-api.amazon.com/:version/checkoutSessions/" \
  // -X POST
  // -H "authorization:Px2e5oHhQZ88vVhc0DO%2FsShHj8MDDg%3DEXAMPLESIGNATURE"
  // -H "x-amz-pay-date:20201012T235046Z"
  // -H "x-amz-pay-idempotency-key:AVLo5tI10BHgEk2jEXAMPLEKEY"
  // -d '{
  //     "webCheckoutDetails": {
  //         "checkoutReviewReturnUrl": "https://a.com/merchant-review-page"
  //     },
  //     "storeId": "amzn1.application-oa2-client.8b5e45312b5248b69eeaStoreId",
  //     "scopes": ["name", "email", "phoneNumber", "billingAddress"],
  //     "deliverySpecifications": {
  //         "specialRestrictions": ["RestrictPOBoxes"],
  //         "addressRestrictions": {
  //             "type": "Allowed",
  //             "restrictions": {
  //                 "US": {
  //                     "statesOrRegions": ["WA"],
  //                     "zipCodes": ["95050", "93405"]
  //                 },
  //                 "GB": {
  //                     "zipCodes": ["72046", "72047"]
  //                 },
  //                 "IN": {
  //                     "statesOrRegions": ["AP"]
  //                 },
  //                 "JP": {}
  //             }
  //         }
  //     }
  // }'

  // Use the following online tool to generate HTTP code from a CURL command
  // Convert a cURL Command to HTTP Source Code

  // Use this online tool to generate code from sample JSON:
  // Generate Code to Create JSON

  // The following JSON is sent in the request body.

  // {
  //   "webCheckoutDetails": {
  //     "checkoutReviewReturnUrl": "https://a.com/merchant-review-page"
  //   },
  //   "storeId": "amzn1.application-oa2-client.8b5e45312b5248b69eeaStoreId",
  //   "scopes": [
  //     "name",
  //     "email",
  //     "phoneNumber",
  //     "billingAddress"
  //   ],
  //   "deliverySpecifications": {
  //     "specialRestrictions": [
  //       "RestrictPOBoxes"
  //     ],
  //     "addressRestrictions": {
  //       "type": "Allowed",
  //       "restrictions": {
  //         "US": {
  //           "statesOrRegions": [
  //             "WA"
  //           ],
  //           "zipCodes": [
  //             "95050",
  //             "93405"
  //           ]
  //         },
  //         "GB": {
  //           "zipCodes": [
  //             "72046",
  //             "72047"
  //           ]
  //         },
  //         "IN": {
  //           "statesOrRegions": [
  //             "AP"
  //           ]
  //         },
  //         "JP": {}
  //       }
  //     }
  //   }
  // }

  final json = CkJsonObject();
  json.updateString('webCheckoutDetails.checkoutReviewReturnUrl', 'https://a.com/merchant-review-page');
  // Make sure to use your storeId here:
  json.updateString('storeId', 'amzn1.application-oa2-client.8b5e45312b5248b69eeaStoreId');
  var i = 0;
  json.i = i;
  json.updateString('scopes[i]', 'name');
  i++;
  json.i = i;
  json.updateString('scopes[i]', 'email');
  i++;
  json.i = i;
  json.updateString('scopes[i]', 'phoneNumber');
  i++;
  json.i = i;
  json.updateString('scopes[i]', 'billingAddress');
  json.updateString('deliverySpecifications.specialRestrictions[0]', 'RestrictPOBoxes');
  json.updateString('deliverySpecifications.addressRestrictions.type', 'Allowed');
  json.updateString('deliverySpecifications.addressRestrictions.restrictions.US.statesOrRegions[0]', 'WA');
  json.updateString('deliverySpecifications.addressRestrictions.restrictions.US.zipCodes[0]', '95050');
  json.updateString('deliverySpecifications.addressRestrictions.restrictions.US.zipCodes[1]', '93405');
  json.updateString('deliverySpecifications.addressRestrictions.restrictions.GB.zipCodes[0]', '72046');
  json.updateString('deliverySpecifications.addressRestrictions.restrictions.GB.zipCodes[1]', '72047');
  json.updateString('deliverySpecifications.addressRestrictions.restrictions.IN.statesOrRegions[0]', 'AP');
  json.updateNewObject('deliverySpecifications.addressRestrictions.restrictions.JP');

  // Load your Amazon Pay private key.  
  // There are many other ways to load private keys into the Chilkat private key object, such as from different formats,
  // or from in-memory strings or bytes.
  final privKey = CkPrivateKey();
  try {
    privKey.loadPemFile('C:/someDir/myAmazonPayPrivateKey.pem');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Provide your Amazon Pay private key and Public Key ID 
  // Use your public key ID here.  It must be the one associated with the private key.
  // Note: The SetAuthPrivateKey method was added in Chilkat v9.5.0.89
  final publicKeyId = 'SANDBOX-AHEGSJCM3L2S637RBGABLAFW';
  try {
    http.setAuthPrivateKey(publicKeyId, privKey);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Note: When the private key is provided as shown above, Chilkat will automatically add the required x-amz-pay-* headers to the HTTP request,
  // and will also sign the request.  Nothing more is needed.
  // Chilkat automatically generates and adds the following headers:
  // 
  // x-amz-pay-date
  // x-amz-pay-host
  // x-amz-pay-region
  // x-amz-pay-idempotency-key
  // Authorization

  http.accept = 'application/json';

  // To use the live system, replace "sandbox" with "live" in the URL passed to HttpJson.
  // Also, make sure to use the correct region: pay-api.amazon.com, pay-api.amazon.eu, or pay-api.amazon.jp
  final resp = CkHttpResponse();
  try {
    http.httpJson('POST', 'https://pay-api.amazon.eu/sandbox/v2/checkoutSessions/', json, 'application/json', resp);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  final sbResponseBody = CkStringBuilder();
  resp.getBodySb(sbResponseBody);
  final jResp = CkJsonObject();
  jResp.loadSb(sbResponseBody);
  jResp.emitCompact = false;

  // If the status code is not equal to 201, this will display error information.
  print('Response Body:');
  print(jResp.emit());

  final respStatusCode = resp.statusCode;
  print('Response Status Code = $respStatusCode');
  if (respStatusCode != 201) {

    // The jResp would've contained an error message, similar to this:
    // 	{
    // 	  "reasonCode": "InvalidHeaderValue",
    // 	  "message": "The value AF2EGWREIPHV2S2TUFFBRDGM provided for PublicKeyId is invalid. Please verify that you are using the PublicKeyId in the correct region and environment."
    // 	}

    print('Failed.');
    return;
  }

  // Sample JSON response:
  // (Sample code for parsing the JSON response is shown below)

  // {
  //   "checkoutSessionId": "bd504926-f659-4ad7-a1a9-9a747aaf5275",
  //   "webCheckoutDetails": {
  //     "checkoutReviewReturnUrl": "https://a.com/merchant-review-page",
  //     "checkoutResultReturnUrl": null,
  //     "checkoutCancelUrl": null,
  //     "amazonPayRedirectUrl": null
  //   },
  //   "productType": "PayAndShip",
  //   "chargePermissionType": "Recurring",
  //   "recurringMetadata": {
  //     "frequency": {
  //       "unit": "Month",
  //       "value": "1"
  //     },
  //     "amount": {
  //       "amount": "30",
  //       "currencyCode": "USD"
  //     }
  //   },
  //   "paymentDetails": {
  //     "paymentIntent": null,
  //     "canHandlePendingAuthorization": false,
  //     "chargeAmount": null,
  //     "totalOrderAmount": null,
  //     "softDescriptor": null,
  //     "presentmentCurrency": null,
  //     "allowOvercharge": null,
  //     "extendExpiration": null
  //   },
  //   "merchantMetadata": {
  //     "merchantReferenceId": null,
  //     "merchantStoreName": null,
  //     "noteToBuyer": null,
  //     "customInformation": null
  //   },
  //   "supplementaryData": null,
  //   "buyer": null,
  //   "billingAddress": null,
  //   "paymentPreferences": [
  //     null
  //   ],
  //   "statusDetails": {
  //     "state": "Open",
  //     "reasonCode": null,
  //     "reasonDescription": null,
  //     "lastUpdatedTimestamp": "20191015T204327Z"
  //   },
  //   "shippingAddress": null,
  //   "platformId": null,
  //   "chargePermissionId": null,
  //   "chargeId": null,
  //   "constraints": [
  //     {
  //       "constraintId": "BuyerNotAssociated",
  //       "description": "There is no buyer associated with the Checkout Session. Return the checkout session id to the Amazon Pay Button to allow buyer to login."
  //     },
  //     {
  //       "constraintId": "ChargeAmountNotSet",
  //       "description": "chargeAmount is not set."
  //     },
  //     {
  //       "constraintId": "CheckoutResultReturnUrlNotSet",
  //       "description": "checkoutResultReturnUrl is not set."
  //     },
  //     {
  //       "constraintId": "PaymentIntentNotSet",
  //       "description": "paymentIntent is not set."
  //     }
  //   ],
  //   "creationTimestamp": "20191015T204313Z",
  //   "expirationTimestamp": "20191016T204313Z",
  //   "storeId": "amzn1.application-oa2-client.8b5e45312b5248b69eeaStoreId",
  //   "deliverySpecifications": {
  //     "specialRestrictions": [
  //       "RestrictPOBoxes"
  //     ],
  //     "addressRestrictions": {
  //       "type": "Allowed",
  //       "restrictions": {
  //         "US": {
  //           "statesOrRegions": [
  //             "WA"
  //           ],
  //           "zipCodes": [
  //             "95050",
  //             "93405"
  //           ]
  //         },
  //         "GB": {
  //           "zipCodes": [
  //             "72046",
  //             "72047"
  //           ]
  //         },
  //         "IN": {
  //           "statesOrRegions": [
  //             "AP"
  //           ]
  //         },
  //         "JP": {}
  //       }
  //     }
  //   },
  //   "providerMetadata": {
  //     "providerReferenceId": null
  //   },
  //   "releaseEnvironment": "Sandbox"
  // }

  // Sample code for parsing the JSON response...
  // Use the following online tool to generate parsing code from sample JSON:
  // Generate Parsing Code from JSON

  var constraintId = '';
  var description = '';
  var strVal = '';

  final checkoutSessionId = jResp.stringOf('checkoutSessionId');
  final webCheckoutDetailsCheckoutReviewReturnUrl = jResp.stringOf('webCheckoutDetails.checkoutReviewReturnUrl');
  final webCheckoutDetailsCheckoutResultReturnUrl = jResp.stringOf('webCheckoutDetails.checkoutResultReturnUrl');
  final webCheckoutDetailsCheckoutCancelUrl = jResp.stringOf('webCheckoutDetails.checkoutCancelUrl');
  final webCheckoutDetailsAmazonPayRedirectUrl = jResp.stringOf('webCheckoutDetails.amazonPayRedirectUrl');
  final productType = jResp.stringOf('productType');
  final chargePermissionType = jResp.stringOf('chargePermissionType');
  final recurringMetadataFrequencyUnit = jResp.stringOf('recurringMetadata.frequency.unit');
  final recurringMetadataFrequencyValue = jResp.stringOf('recurringMetadata.frequency.value');
  final recurringMetadataAmountAmount = jResp.stringOf('recurringMetadata.amount.amount');
  final recurringMetadataAmountCurrencyCode = jResp.stringOf('recurringMetadata.amount.currencyCode');
  final paymentDetailsPaymentIntent = jResp.stringOf('paymentDetails.paymentIntent');
  final paymentDetailsChargeAmount = jResp.stringOf('paymentDetails.chargeAmount');
  final paymentDetailsTotalOrderAmount = jResp.stringOf('paymentDetails.totalOrderAmount');
  final paymentDetailsSoftDescriptor = jResp.stringOf('paymentDetails.softDescriptor');
  final paymentDetailsPresentmentCurrency = jResp.stringOf('paymentDetails.presentmentCurrency');
  final paymentDetailsAllowOvercharge = jResp.stringOf('paymentDetails.allowOvercharge');
  final paymentDetailsExtendExpiration = jResp.stringOf('paymentDetails.extendExpiration');
  final merchantMetadataMerchantReferenceId = jResp.stringOf('merchantMetadata.merchantReferenceId');
  final merchantMetadataMerchantStoreName = jResp.stringOf('merchantMetadata.merchantStoreName');
  final merchantMetadataNoteToBuyer = jResp.stringOf('merchantMetadata.noteToBuyer');
  final merchantMetadataCustomInformation = jResp.stringOf('merchantMetadata.customInformation');
  final supplementaryData = jResp.stringOf('supplementaryData');
  final buyer = jResp.stringOf('buyer');
  final billingAddress = jResp.stringOf('billingAddress');
  final statusDetailsState = jResp.stringOf('statusDetails.state');
  final statusDetailsReasonCode = jResp.stringOf('statusDetails.reasonCode');
  final statusDetailsReasonDescription = jResp.stringOf('statusDetails.reasonDescription');
  final statusDetailsLastUpdatedTimestamp = jResp.stringOf('statusDetails.lastUpdatedTimestamp');
  final shippingAddress = jResp.stringOf('shippingAddress');
  final platformId = jResp.stringOf('platformId');
  final chargePermissionId = jResp.stringOf('chargePermissionId');
  final chargeId = jResp.stringOf('chargeId');
  final creationTimestamp = jResp.stringOf('creationTimestamp');
  final expirationTimestamp = jResp.stringOf('expirationTimestamp');
  final storeId = jResp.stringOf('storeId');
  final deliverySpecificationsAddressRestrictionsType = jResp.stringOf('deliverySpecifications.addressRestrictions.type');
  final providerMetadataProviderReferenceId = jResp.stringOf('providerMetadata.providerReferenceId');
  final releaseEnvironment = jResp.stringOf('releaseEnvironment');
  i = 0;
  var countI = jResp.sizeOfArray('paymentPreferences');
  while (i < countI) {
    jResp.i = i;
    jResp.isNullOf('paymentPreferences[i]');
    i++;
  }

  i = 0;
  countI = jResp.sizeOfArray('constraints');
  while (i < countI) {
    jResp.i = i;
    constraintId = jResp.stringOf('constraints[i].constraintId');
    description = jResp.stringOf('constraints[i].description');
    i++;
  }

  i = 0;
  countI = jResp.sizeOfArray('deliverySpecifications.specialRestrictions');
  while (i < countI) {
    jResp.i = i;
    strVal = jResp.stringOf('deliverySpecifications.specialRestrictions[i]');
    i++;
  }

  i = 0;
  countI = jResp.sizeOfArray('deliverySpecifications.addressRestrictions.restrictions.US.statesOrRegions');
  while (i < countI) {
    jResp.i = i;
    strVal = jResp.stringOf('deliverySpecifications.addressRestrictions.restrictions.US.statesOrRegions[i]');
    i++;
  }

  i = 0;
  countI = jResp.sizeOfArray('deliverySpecifications.addressRestrictions.restrictions.US.zipCodes');
  while (i < countI) {
    jResp.i = i;
    strVal = jResp.stringOf('deliverySpecifications.addressRestrictions.restrictions.US.zipCodes[i]');
    i++;
  }

  i = 0;
  countI = jResp.sizeOfArray('deliverySpecifications.addressRestrictions.restrictions.GB.zipCodes');
  while (i < countI) {
    jResp.i = i;
    strVal = jResp.stringOf('deliverySpecifications.addressRestrictions.restrictions.GB.zipCodes[i]');
    i++;
  }

  i = 0;
  countI = jResp.sizeOfArray('deliverySpecifications.addressRestrictions.restrictions.IN.statesOrRegions');
  while (i < countI) {
    jResp.i = i;
    strVal = jResp.stringOf('deliverySpecifications.addressRestrictions.restrictions.IN.statesOrRegions[i]');
    i++;
  }
}