IT Retail

API: Customers

January 26, 2026January 26, 2026

Connect your store's Customers information to another application using an Application Programming Interface (API). This article will show you what to place in API Endpoints for multiple purposes involving your customer records.

 

API: Customers

Since API setup involves a lot of technical language, we'll first define some terms so you have a better understanding of this article.

  • Request: This is what you send the API endpoint so it performs a specific task. For example, for the GetAllCustomers function below, you'll paste the Request so the API can get all customer data.

  • Response: The API server will give you a Response to your Request. This will indicate if the task was successful, as well as the data you requested.

  • Guide: We'll provide you with a guide so you know how to read Responses or fill out Requests.

 

GetAllCustomers

These functions will gather all of your customer records.

  • Request

curl --location --request GET 'https://retailnext.itretail.com/api/CustomersData/GetAllCustomers'; \
--header 'Authorization: Bearer vab5uvKIA4tKbAsLn7eRaxw_nmiQ9OePRh1B0tofAgFZSjWqguihzAO1XfY3pMMUqqSVUNFPpp98kUH8TL34ESyUvuLnOCjkITLLGv7ohTKUCymeEtMfV2Tj3lUGsDUuRJId3zx5PTgjhGnrLF8bGY7f6KMMdOiV1L00gGmpplwndAkiKDTh7mLT7xZrqvGVUMp1etJ0NQjrU0BQgH5iEgFoCLtB-DTpkdcS0rEbM10iSTZ4_ctPkA51_Cj6BdOMTOafp7Pfax7vdJ97SMXVz72Ceoag3XfLzhOxkrx6JtN5B9Zh7Sy6pWuxNe2m_snl24UZpjonz3AGtnG1Qr0czAzYxhugoqWxP_jlKkGhQc4uShCI4_jqCEMs-CkMwBokfGpIv4H0-BiAjF7VVFobRXPPCmQRVW-gIrZkAs5hQ70G_bB9pkv2-UfO4mN7dO5AcVxRnJG18pr7w3f47vxFELh8iwo'
  • Example of a Response

[
{
"Id": "070135c5-e228-4518-adc0-042ed2e784d8",
"CardNo": "0061234500020",
"LastName": "Zimmermann",
"FirstName": "Helmut",
"BirthDate": null,
"Phone": null,
"Discount": 10,
"Deleted": false,
"Email": null,
"Balance": 0.0000,
"BalanceLimit": null,
"LoyaltyPoints": 658,
"ExpirationDate": "2021-05-04T00:00:00",
"InstoreChargeEnabled": false
},
{
"Id": "df165306-6401-431e-abd6-136r68c50a31",
"CardNo": "0061234500007",
"LastName": "Von Poe",
"FirstName": "Stephanie",
"BirthDate": null,
"Phone": null,
"Discount": 10,
"Deleted": false,
"Email": null,
"Balance": 320.1900,
"BalanceLimit": 500.0000,
"LoyaltyPoints": 230,
"ExpirationDate": "2021-11-19T22:00:00",
"InstoreChargeEnabled": true
}
]
  • Guide for information in the above Response
Id                   : Guid      - Unique identifier for the customer
CardNo : string - Customer loyalty card number
LastName : string - Last name of the customer
FirstName : string - First name of the customer
BirthDate : DateTime? - Birth date of the customer
Phone : string - Phone number of the customer
Discount : short? - Percentage discount represented as a whole number (e.g. 10% = 10)
Deleted : boolean - Flag to indicate a deleted customer
Email : string - Email address of the customer
Balance : decimal? - Current instore charge balance
BalanceLimit : decimal? - Ceiling amount for the instore charge balance
LoyaltyPoints : int? - Loyalty points accrued by the customer
ExpirationDate : DateTime? - Customer expiration date
InstoreChargeEnabled : boolean - Flag to indicate the ability to make instore charge transactions

 

GetCustomerProductPurchases

These functions will gather all products that customers purchased from a day you specify.

  • Request

curl --location --request GET 'https://retailnext.itretail.com/api/CustomersData/GetCustomerProductPurchases?date=03/08/2021'; \
--header 'Authorization: Bearer vab5uvKIB4tKbAsLn7eRaxw_nmiQ9OePRh1B0tofAgFZSjWqguihzAO1XfY3pMMUqqSVUNFPpp98kUH8TL34ESyUvuLnOCjkITLLGv7ohTKUCymeEtMfV2Tj3lUGsDUuRJId3zx5PTgjhGnrLF8bGY7f6KMMdOiV1L00gGmpplwndAkiKDTh7mLT7xZrqvGVUMp1etJ0NQjrU0BQgH5iEgFoCLtB-DTpkdcS0rEbM10iSTZ4_ctPkA51_Cj6BdOMTOafp7Pfax7vdJ97SMXVz72Ceoag3XfLzhOxkrx6JtN5B9Zh7Sy6pWuxNe2m_snl24UZpjonz3AGtnG1Qr0czAzYxhugoqWxP_jlKkGhQc4uShCI4_jqCEMs-CkMwBokfGpIv4H0-BiAjF7VVFobRXPPCmQRVW-gIrZkAs5hQ70G_bB9pkv2-UfO4mN7dO5AcVxRnJG18pr7w3f47vxFELh8iwo'
  • Example of a Response

[
{
"Id": "24f9831f-a410-49db-ac86-25d2e493ae99",
"CardNumber": "0061234500004",
"ProductsPurchased": [
"0038137117501",
"0001300099490",
"0001111084765",
"0020011200000",
"0023130000000"
]
},
{
"Id": "91c2645c-5c4d-4da4-b789-2f737a388db3",
"CardNumber": "0061234500005",
"ProductsPurchased": [
"0000000000012",
"0000000000012",
"0000000000012",
"0000000000012",
"0000000000001",
"0000000000001",
"0000000000001",
"0000000004015",
]
}
}
  • Guide for information in the above Response
Id                : Guid     - Unique identifier for the customer
CardNumber : string - Loyalty card number for the customer
ProductsPurchased : string[] - Unaggregated array of UPCs that were purchased by the customer for the requested day

 

CreateCustomer

These create a new customer and includes the given fields. Make sure to replace the placeholder terms for First Name, Last Name, Email, and Phone.

  • Request

curl --location --request POST 'https://retailnext.itretail.com/api/CustomersData/Post'; \
--header 'Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.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.iHSrM1KwmJ4IfaT_Cd6UA8XCVcgDc5Y8ojmSItsXLjU' \
--header 'Content-Type: application/json' \
--data-raw '{
FirstName: "Fake",
LastName: "Customer",
Email: "fakecustomer@mail.com",
Phone: "1235551234"
}'
  • Guide for information in above Request (You'll need to fill out this information in the Request yourself)
FirstName         : string   - First name of the customer
LastName : string - Last name of the customer
Email : string - Customer email, must be unique from other customers
Phone : string - Unformatted 10 digit phone number ex. "1235551231"

 

GetCustomer

  • Request

curl --location --request GET 'https://retailnext.itretail.com/api/CustomersData/GetOne/?Id=c5b20c93-210c-464d-b533-58186aca4f4e'; \
--header 'Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cAI6IkpXVCJ9.eyJuYW1lIjoic3VhbkBpdHJldGFpbC5jb20iLCG0Zb5hbvRJZCI6Ijg1MTA2NTk4LTA4YzktNDVlMC04YzUzLTlm-2ReZGYyRwSlZiIs1nBlcX1pc31pb25zIjoiMSwyLDMsNCw2LDcsOCw5LDExLDEyLDE0LDE1LDE2LDE3LDE4LDE5LDIwLDIxLDIzLDMyLDUsMTMsMjIsMjcsMjksMzAsMzEsMzMsMzQsMzUsMzYsMzcsMzgsMzksNDAsNDEsNDQsNTgsNTMsNTQsNTUsNTYsNTcsMjYsNDUsNTIsNDIsNTksMjQsNDMsNDYsNDgsNTAsNTEsNjAsNjEsMTAsMTAwLDYyLDYzIiwiZW1wbG95ZWVJZCI6IjEiLCJhY2Nlc3NMZXZlbCI6IkVtcGxveWVlIiwibmJmIjoxNjI3NDg0MDEzLCJleHAiOjE2Mjg2OTM2MTMsImlzcyI6IklUUmV0YWlsIiwiYXVkIjoiSVRSZXRhaWwifQ.TSGAH6EePS7I372Qky_xwcGBTxe0ZiKJh4JBaW_STGk'
  • Example of a Response

{
"Id": "c5b20c93-210c-464d-b533-58186aca4f4e",
"CardNo": "0041234500897",
"LastName": "Alonzo",
"FirstName": "Theresa",
"BirthDate": null,
"Address1": null,
"Address2": null,
"Phone": null,
"City": null,
"State": null,
"Zip": null,
"CashBack": 0.0000,
"Discount": 10,
"FrequentShopper": null,
"WriteChecks": true,
"Type": null,
"Purchases": 0.0000,
"NumberOfChecks": 0,
"PointsEarned": 0,
"Deleted": false,
"Created": "2021-03-04T08:27:35.56",
"Modified": "2021-07-26T14:57:37.367",
"ModifiedBy": 1,
"ReceiptType": null,
"Email": null,
"Attributes": 4,
"TenantId": "85106598-08c9-45e0-8c53-9f7dcdf297ef",
"PaymentToken": null,
"Inc": 44727,
"Balance": null,
"BalanceLimit": 500.0000,
"LoyaltyPoints": 500,
"expiration_date": "2021-03-16T05:00:00",
"CustomerBalanceOperations": [],
"CustomerCoupons": [],
"CustomerGroupCustomers": [],
"CustomerLoyaltyPointOperations": [],
"TransactionLoyaltyOperations": []
}

 

UpdateCustomer

This will update the customer record. We recommend you first perform a Get function, like GetCustomer, so you can avoid overwriting changes. 

Please note: All fields have to be successful. If not, any skipped fields will be nullified.

  • Request

curl --location --request PUT 'https://retailnext.itretail.com/api/CustomersData/Put'; \
--header 'Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cAI6IkpXVCJ9.eyJuYW1lIjoic3VhbkBpdHJldGFpbC5jb20iLCG0Zb5hbvRJZCI6Ijg1MTA2NTk4LTA4YzktNDVlMC04YzUzLTlm-2ReZGYyRwSlZiIs1nBlcX1pc31pb25zIjoiMSwyLDMsNCw2LDcsOCw5LDExLDEyLDE0LDE1LDE2LDE3LDE4LDE5LDIwLDIxLDIzLDMyLDUsMTMsMjIsMjcsMjksMzAsMzEsMzMsMzQsMzUsMzYsMzcsMzgsMzksNDAsNDEsNDQsNTgsNTMsNTQsNTUsNTYsNTcsMjYsNDUsNTIsNDIsNTksMjQsNDMsNDYsNDgsNTAsNTEsNjAsNjEsMTAsMTAwLDYyLDYzIiwiZW1wbG95ZWVJZCI6IjEiLCJhY2Nlc3NMZXZlbCI6IkVtcGxveWVlIiwibmJmIjoxNjI3NDg0MDEzLCJleHAiOjE2Mjg2OTM2MTMsImlzcyI6IklUUmV0YWlsIiwiYXVkIjoiSVRSZXRhaWwifQ.TSGAH6EePS7I372Qky_xwcGBTxe0ZiKJh4JBaW_STGk' \
--header 'Content-Type: application/json' \
--data-raw '{
"Id": "c5b20c93-210c-464d-b533-58186aca4f4e",
"CardNo": "0041234500897",
"LastName": "Alonzo",
"FirstName": "Theresa",
"BirthDate": null,
"Address1": null,
"Address2": null,
"Phone": null,
"City": null,
"State": null,
"Zip": null,
"CashBack": 0.0000,
"Discount": 10,
"FrequentShopper": null,
"WriteChecks": true,
"Type": null,
"Purchases": 0.0000,
"NumberOfChecks": 0,
"PointsEarned": 0,
"Deleted": false,
"Created": "2021-03-04T08:27:35.56",
"Modified": "2021-07-26T14:57:37.367",
"ModifiedBy": 1,
"ReceiptType": null,
"Email": null,
"Attributes": 4,
"TenantId": "85106598-08c9-45e0-8c53-9f7dcdf297ef",
"PaymentToken": null,
"Inc": 44727,
"Balance": null,
"BalanceLimit": 500.0000,
"LoyaltyPoints": 50,
"expiration_date": "2021-03-16T05:00:00",
"CustomerBalanceOperations": [],
"CustomerCoupons": [],
"CustomerGroupCustomers": [],
"CustomerLoyaltyPointOperations": [],
"TransactionLoyaltyOperations": []
}'
  • Example of a Response

{
"Id": "c5b20c93-210c-464d-b533-58186aca4f4e",
"CardNo": "0041234500897",
"LastName": "Alonzo",
"FirstName": "Theresa",
"BirthDate": null,
"Address1": null,
"Address2": null,
"Phone": null,
"City": null,
"State": null,
"Zip": null,
"CashBack": 0.0000,
"Discount": 10,
"FrequentShopper": null,
"WriteChecks": true,
"Type": null,
"Purchases": 0.0000,
"NumberOfChecks": 0,
"PointsEarned": 0,
"Deleted": false,
"Created": "2021-03-04T08:27:35.56",
"Modified": "2021-07-28T15:24:47.763091Z",
"ModifiedBy": 1,
"ReceiptType": null,
"Email": null,
"Attributes": 4,
"TenantId": "85106598-08c9-45e0-8c53-9f7dcdf297ef",
"PaymentToken": null,
"Inc": 44727,
"Balance": null,
"BalanceLimit": 500.0000,
"LoyaltyPoints": 50,
"expiration_date": "2021-03-16T05:00:00",
"CustomerBalanceOperations": [],
"CustomerCoupons": [],
"CustomerGroupCustomers": [],
"CustomerLoyaltyPointOperations": [
{
"Id": "d3ee2dd1-67ce-4198-a433-937402fc3cfa",
"TenantId": "85106598-08c9-45e0-8c53-9f7dcdf297ef",
"CustomerId": "c5b20c93-210c-464d-b533-58186aca4f4e",
"LoyaltyPointsAdded": -500,
"LoyaltyPointsAfterAdd": 50,
"OperationDate": "2021-07-28T15:24:47.763091+00:00",
"IsManualUpdate": true,
"TransactionId": null,
"Tenant": null,
"Transaction": null
}
],
"TransactionLoyaltyOperations": []
}

 

Related Articles

API: Customers

API: Tokens

POS Manager API Setup

 

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