(Visual Basic 6.0) Amazon Pay - Create Checkout Session

See more Amazon Pay Examples

Create a new Amazon Pay Checkout Session.

Note: This example requires Chilkat v9.5.0.89 or later. Contact support@chilkatsoft.com to get a v9.5.0.89 pre-release for testing.

For more information, see https://developer.amazon.com/docs/amazon-pay-api-v2/checkout-session.html#create-checkout-session

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

' This example assumes the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

Dim http As New ChilkatHttp
Dim success As Long

' 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": {}
'       }
'     }
'   }
' }

Dim json As New ChilkatJsonObject
success = json.UpdateString("webCheckoutDetails.checkoutReviewReturnUrl","https://a.com/merchant-review-page")
' Make sure to use your storeId here:
success = json.UpdateString("storeId","amzn1.application-oa2-client.8b5e45312b5248b69eeaStoreId")
Dim i As Long
i = 0
json.I = i
success = json.UpdateString("scopes[i]","name")
i = i + 1
json.I = i
success = json.UpdateString("scopes[i]","email")
i = i + 1
json.I = i
success = json.UpdateString("scopes[i]","phoneNumber")
i = i + 1
json.I = i
success = json.UpdateString("scopes[i]","billingAddress")
success = json.UpdateString("deliverySpecifications.specialRestrictions[0]","RestrictPOBoxes")
success = json.UpdateString("deliverySpecifications.addressRestrictions.type","Allowed")
success = json.UpdateString("deliverySpecifications.addressRestrictions.restrictions.US.statesOrRegions[0]","WA")
success = json.UpdateString("deliverySpecifications.addressRestrictions.restrictions.US.zipCodes[0]","95050")
success = json.UpdateString("deliverySpecifications.addressRestrictions.restrictions.US.zipCodes[1]","93405")
success = json.UpdateString("deliverySpecifications.addressRestrictions.restrictions.GB.zipCodes[0]","72046")
success = json.UpdateString("deliverySpecifications.addressRestrictions.restrictions.GB.zipCodes[1]","72047")
success = json.UpdateString("deliverySpecifications.addressRestrictions.restrictions.IN.statesOrRegions[0]","AP")
success = 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.
Dim privKey As New PrivateKey
success = privKey.LoadPemFile("C:/someDir/myAmazonPayPrivateKey.pem")
If (success = 0) Then
    Debug.Print privKey.LastErrorText
    Exit Sub
End If

' 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
Dim publicKeyId As String
publicKeyId = "SANDBOX-AHEGSJCM3L2S637RBGABLAFW"
success = http.SetAuthPrivateKey(publicKeyId,privKey)
If (success = 0) Then
    Debug.Print http.LastErrorText
    Exit Sub
End If

' 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 PostJson3.
' Also, make sure to use the correct region: pay-api.amazon.com, pay-api.amazon.eu, or pay-api.amazon.jp
Dim resp As ChilkatHttpResponse
Set resp = http.PostJson3("https://pay-api.amazon.eu/sandbox/v2/checkoutSessions/","application/json",json)
If (http.LastMethodSuccess = 0) Then
    Debug.Print http.LastErrorText
    Exit Sub
End If

Dim sbResponseBody As New ChilkatStringBuilder
success = resp.GetBodySb(sbResponseBody)
Dim jResp As New ChilkatJsonObject
success = jResp.LoadSb(sbResponseBody)
jResp.EmitCompact = 0

' If the status code is not equal to 201, this will display error information.
Debug.Print "Response Body:"
Debug.Print jResp.Emit()

Dim respStatusCode As Long
respStatusCode = resp.StatusCode
Debug.Print "Response Status Code = " & respStatusCode
If (respStatusCode <> 201) Then

    ' 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."
    ' 	}

    Debug.Print "Failed."

    Exit Sub
End If

' 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

Dim nullVal As Long
Dim constraintId As String
Dim description As String
Dim strVal As String

Dim checkoutSessionId As String
checkoutSessionId = jResp.StringOf("checkoutSessionId")
Dim webCheckoutDetailsCheckoutReviewReturnUrl As String
webCheckoutDetailsCheckoutReviewReturnUrl = jResp.StringOf("webCheckoutDetails.checkoutReviewReturnUrl")
Dim webCheckoutDetailsCheckoutResultReturnUrl As String
webCheckoutDetailsCheckoutResultReturnUrl = jResp.StringOf("webCheckoutDetails.checkoutResultReturnUrl")
Dim webCheckoutDetailsCheckoutCancelUrl As String
webCheckoutDetailsCheckoutCancelUrl = jResp.StringOf("webCheckoutDetails.checkoutCancelUrl")
Dim webCheckoutDetailsAmazonPayRedirectUrl As String
webCheckoutDetailsAmazonPayRedirectUrl = jResp.StringOf("webCheckoutDetails.amazonPayRedirectUrl")
Dim productType As String
productType = jResp.StringOf("productType")
Dim chargePermissionType As String
chargePermissionType = jResp.StringOf("chargePermissionType")
Dim recurringMetadataFrequencyUnit As String
recurringMetadataFrequencyUnit = jResp.StringOf("recurringMetadata.frequency.unit")
Dim recurringMetadataFrequencyValue As String
recurringMetadataFrequencyValue = jResp.StringOf("recurringMetadata.frequency.value")
Dim recurringMetadataAmountAmount As String
recurringMetadataAmountAmount = jResp.StringOf("recurringMetadata.amount.amount")
Dim recurringMetadataAmountCurrencyCode As String
recurringMetadataAmountCurrencyCode = jResp.StringOf("recurringMetadata.amount.currencyCode")
Dim paymentDetailsPaymentIntent As String
paymentDetailsPaymentIntent = jResp.StringOf("paymentDetails.paymentIntent")
Dim paymentDetailsCanHandlePendingAuthorization As Long
paymentDetailsCanHandlePendingAuthorization = jResp.BoolOf("paymentDetails.canHandlePendingAuthorization")
Dim paymentDetailsChargeAmount As String
paymentDetailsChargeAmount = jResp.StringOf("paymentDetails.chargeAmount")
Dim paymentDetailsTotalOrderAmount As String
paymentDetailsTotalOrderAmount = jResp.StringOf("paymentDetails.totalOrderAmount")
Dim paymentDetailsSoftDescriptor As String
paymentDetailsSoftDescriptor = jResp.StringOf("paymentDetails.softDescriptor")
Dim paymentDetailsPresentmentCurrency As String
paymentDetailsPresentmentCurrency = jResp.StringOf("paymentDetails.presentmentCurrency")
Dim paymentDetailsAllowOvercharge As String
paymentDetailsAllowOvercharge = jResp.StringOf("paymentDetails.allowOvercharge")
Dim paymentDetailsExtendExpiration As String
paymentDetailsExtendExpiration = jResp.StringOf("paymentDetails.extendExpiration")
Dim merchantMetadataMerchantReferenceId As String
merchantMetadataMerchantReferenceId = jResp.StringOf("merchantMetadata.merchantReferenceId")
Dim merchantMetadataMerchantStoreName As String
merchantMetadataMerchantStoreName = jResp.StringOf("merchantMetadata.merchantStoreName")
Dim merchantMetadataNoteToBuyer As String
merchantMetadataNoteToBuyer = jResp.StringOf("merchantMetadata.noteToBuyer")
Dim merchantMetadataCustomInformation As String
merchantMetadataCustomInformation = jResp.StringOf("merchantMetadata.customInformation")
Dim supplementaryData As String
supplementaryData = jResp.StringOf("supplementaryData")
Dim buyer As String
buyer = jResp.StringOf("buyer")
Dim billingAddress As String
billingAddress = jResp.StringOf("billingAddress")
Dim statusDetailsState As String
statusDetailsState = jResp.StringOf("statusDetails.state")
Dim statusDetailsReasonCode As String
statusDetailsReasonCode = jResp.StringOf("statusDetails.reasonCode")
Dim statusDetailsReasonDescription As String
statusDetailsReasonDescription = jResp.StringOf("statusDetails.reasonDescription")
Dim statusDetailsLastUpdatedTimestamp As String
statusDetailsLastUpdatedTimestamp = jResp.StringOf("statusDetails.lastUpdatedTimestamp")
Dim shippingAddress As String
shippingAddress = jResp.StringOf("shippingAddress")
Dim platformId As String
platformId = jResp.StringOf("platformId")
Dim chargePermissionId As String
chargePermissionId = jResp.StringOf("chargePermissionId")
Dim chargeId As String
chargeId = jResp.StringOf("chargeId")
Dim creationTimestamp As String
creationTimestamp = jResp.StringOf("creationTimestamp")
Dim expirationTimestamp As String
expirationTimestamp = jResp.StringOf("expirationTimestamp")
Dim storeId As String
storeId = jResp.StringOf("storeId")
Dim deliverySpecificationsAddressRestrictionsType As String
deliverySpecificationsAddressRestrictionsType = jResp.StringOf("deliverySpecifications.addressRestrictions.type")
Dim providerMetadataProviderReferenceId As String
providerMetadataProviderReferenceId = jResp.StringOf("providerMetadata.providerReferenceId")
Dim releaseEnvironment As String
releaseEnvironment = jResp.StringOf("releaseEnvironment")
i = 0
Dim count_i As Long
count_i = jResp.SizeOfArray("paymentPreferences")
Do While i < count_i
    jResp.I = i
    nullVal = jResp.IsNullOf("paymentPreferences[i]")
    i = i + 1
Loop
i = 0
count_i = jResp.SizeOfArray("constraints")
Do While i < count_i
    jResp.I = i
    constraintId = jResp.StringOf("constraints[i].constraintId")
    description = jResp.StringOf("constraints[i].description")
    i = i + 1
Loop
i = 0
count_i = jResp.SizeOfArray("deliverySpecifications.specialRestrictions")
Do While i < count_i
    jResp.I = i
    strVal = jResp.StringOf("deliverySpecifications.specialRestrictions[i]")
    i = i + 1
Loop
i = 0
count_i = jResp.SizeOfArray("deliverySpecifications.addressRestrictions.restrictions.US.statesOrRegions")
Do While i < count_i
    jResp.I = i
    strVal = jResp.StringOf("deliverySpecifications.addressRestrictions.restrictions.US.statesOrRegions[i]")
    i = i + 1
Loop
i = 0
count_i = jResp.SizeOfArray("deliverySpecifications.addressRestrictions.restrictions.US.zipCodes")
Do While i < count_i
    jResp.I = i
    strVal = jResp.StringOf("deliverySpecifications.addressRestrictions.restrictions.US.zipCodes[i]")
    i = i + 1
Loop
i = 0
count_i = jResp.SizeOfArray("deliverySpecifications.addressRestrictions.restrictions.GB.zipCodes")
Do While i < count_i
    jResp.I = i
    strVal = jResp.StringOf("deliverySpecifications.addressRestrictions.restrictions.GB.zipCodes[i]")
    i = i + 1
Loop
i = 0
count_i = jResp.SizeOfArray("deliverySpecifications.addressRestrictions.restrictions.IN.statesOrRegions")
Do While i < count_i
    jResp.I = i
    strVal = jResp.StringOf("deliverySpecifications.addressRestrictions.restrictions.IN.statesOrRegions[i]")
    i = i + 1
Loop