# POST /api/merchants/{id}/registers Register: creates or replaces a single register on the merchant. Example: `POST /api/merchants/3fa85f64-5717-4562-b3fc-2c963f66afa6/registers` with body ``` { "friendlyId": "LANE1", "name": "Front lane", "enabled": true } ``` Every other register and merchant setting is left untouched. A validation failure is reported under an indexed member name (`Registers[0].friendlyId`), matching the full-document save. POST rather than PUT, deliberately: the path names the collection, and `PUT` there reads as "replace the collection", which is the one thing this endpoint promises not to do. It shares the path with the existing `GET /api/merchants/{id}/registers` list read. **Operation ID:** `registersSaveRegister` ## Authorization Requires: Merchants.Merchants.Update, merchant scope. Requires API key scope: `admin` Required permissions: - `Merchants.Merchants.Update` ## Parameters | Name | In | Required | Type | Description | | --- | --- | --- | --- | --- | | id | path | yes | string(uuid) | The merchant id. | | If-Match | header | no | string | The merchant's concurrency stamp, read from the `If-Match` header. When supplied and stale the write is rejected with 409; when omitted, no concurrency check is performed. | | suppressNulls | query | no | boolean | If true, omit properties with null values. | ## Request Body The register to create or replace. A supplied `legacyNumber` addresses an existing register and a miss is a 404; omitted, a matching `id` replaces and no match creates. Both `id` and `legacyNumber` are server-owned in the result. **Content type:** `application/json` Schema: [`MerchantRegisterDto`](https://devportal.demo.winkpg.io/docs/api/models/MerchantRegisterDto.md) Properties: - `id` (string(uuid)) - `friendlyId` (string) required: A user-friendly identifier for this register. Required. (nullable, min length 3, max length 20) - `name` (string): A unique name for this register. Optional. (nullable) - `description` (string): A brief description of this register and/or its purpose. Optional. (nullable, max length 40) - `enabled` (boolean) - `terminal1` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal2` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal3` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal4` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal5` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `legacyNumber` (integer(int64)): The integer key the v1 API addresses this register by (its `RegisterKey`). Server-owned: allocated once, when the register is first saved, and never reassigned. (nullable) **Content type:** `text/json` Schema: [`MerchantRegisterDto`](https://devportal.demo.winkpg.io/docs/api/models/MerchantRegisterDto.md) Properties: - `id` (string(uuid)) - `friendlyId` (string) required: A user-friendly identifier for this register. Required. (nullable, min length 3, max length 20) - `name` (string): A unique name for this register. Optional. (nullable) - `description` (string): A brief description of this register and/or its purpose. Optional. (nullable, max length 40) - `enabled` (boolean) - `terminal1` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal2` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal3` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal4` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal5` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `legacyNumber` (integer(int64)): The integer key the v1 API addresses this register by (its `RegisterKey`). Server-owned: allocated once, when the register is first saved, and never reassigned. (nullable) **Content type:** `application/*+json` Schema: [`MerchantRegisterDto`](https://devportal.demo.winkpg.io/docs/api/models/MerchantRegisterDto.md) Properties: - `id` (string(uuid)) - `friendlyId` (string) required: A user-friendly identifier for this register. Required. (nullable, min length 3, max length 20) - `name` (string): A unique name for this register. Optional. (nullable) - `description` (string): A brief description of this register and/or its purpose. Optional. (nullable, max length 40) - `enabled` (boolean) - `terminal1` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal2` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal3` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal4` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `terminal5` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)): A terminal slot on a `MerchantRegister`. Fields: - `id` (string(uuid)) - `terminalNumber` (string): The terminal number assigned to this slot. Optional; typically null. (nullable) - `masterKeyPointer` (string): The master key pointer for this slot. Optional; typically null. (nullable) - `workingKey` (string): The working key for this slot. Optional; typically null. (nullable) - `lastRecordNumber` (string): The last record number seen on this slot. Optional; typically null. (nullable) - `legacyNumber` (integer(int64)): The integer key the v1 API addresses this register by (its `RegisterKey`). Server-owned: allocated once, when the register is first saved, and never reassigned. (nullable) ## Responses ### 200 OK **Content type:** `application/json` Schema: [`MerchantRegisterWriteResultDto`](https://devportal.demo.winkpg.io/docs/api/models/MerchantRegisterWriteResultDto.md) Properties: - `merchantId` (string(uuid)): The merchant that owns the register. - `register` ([MerchantRegisterDto](https://devportal.demo.winkpg.io/docs/api/models/MerchantRegisterDto.md)): The register as persisted, including the server-owned `id` and `legacyNumber`. Fields: - `id` (string(uuid)) - `friendlyId` (string) required: A user-friendly identifier for this register. Required. (nullable, min length 3, max length 20) - `name` (string): A unique name for this register. Optional. (nullable) - `description` (string): A brief description of this register and/or its purpose. Optional. (nullable, max length 40) - `enabled` (boolean) - `terminal1` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)) - `terminal2` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)) - `terminal3` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)) - `terminal4` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)) - `terminal5` ([RegisterTerminal](https://devportal.demo.winkpg.io/docs/api/models/RegisterTerminal.md)) - `legacyNumber` (integer(int64)): The integer key the v1 API addresses this register by (its `RegisterKey`). Server-owned: allocated once, when the register is first saved, and never reassigned. (nullable) - `created` (boolean): `true` when the write added a register, `false` when it replaced an existing one. Lets a caller that publishes distinct create and update verbs report the right one without comparing collections before and after. - `merchantConcurrencyStamp` (string): The owning merchant's concurrency stamp after the write. (nullable) ### 403 Forbidden **Content type:** `application/json` Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md) Properties: - `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md)) ### 401 Unauthorized **Content type:** `application/json` Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md) Properties: - `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md)) ### 400 Bad Request **Content type:** `application/json` Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md) Properties: - `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md)) _Example: Request failed validation_ One or more fields were rejected before any rule ran. error.code is null on the envelope and the causes are in validationErrors, one entry per failure. An entry carries code when the validator declared a publishable one, and memberPaths when the full path says more than members does (an element inside a collection, for example). Both keys are omitted when they would add nothing. ```json { "error": { "code": "null", "message": "Your request is not valid!", "details": "The following errors were detected during validation.", "data": { "correlationId": "0123456789abcdef0123456789abcdef" }, "validationErrors": [ { "message": "'Amount' must be greater than 0.", "members": [ "amount" ] }, { "message": "The card has expired.", "members": [ "expirationDate" ], "code": "CardData:CardExpired" }, { "message": "'Value' must not be empty.", "members": [ "value" ], "memberPaths": [ "customFields[2].value" ] } ] } } ``` ### 404 Not Found **Content type:** `application/json` Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md) Properties: - `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md)) _Example: Resource not found_ The id in the path names no record the caller can see. Most resources answer with a null error.code and a message naming the resource type and the id; a resource that publishes a not-found code in the catalog above carries it in error.code instead, so check for one before matching on the message. ```json { "error": { "code": "null", "message": "There is no entity Transaction with id = 7d1f3a52-0c4e-4b8a-9e21-5a6b7c8d9e00!", "details": "null", "data": { "correlationId": "0123456789abcdef0123456789abcdef" }, "validationErrors": "null" } } ``` ### 501 Not Implemented **Content type:** `application/json` Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md) Properties: - `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md)) ### 500 Internal Server Error **Content type:** `application/json` Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md) Properties: - `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md)) ### default The request failed. The body carries the standard error envelope: a machine-readable `error.code`, a human-readable `error.message`, and `error.validationErrors` when the failure was a validation rejection. The [error reference](https://devportal.demo.winkpg.io/docs/errors.md) lists the values `error.code` can take. **Content type:** `application/json` Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md) Properties: - `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md)) _Example: Business rule refused the request_ The request was understood and rejected by a platform rule. This is the shape that carries a code from the catalog above, so branch on error.code rather than on the message text. The HTTP status is the one listed against the code. ```json { "error": { "code": "Transactions:OperationNotAllowed", "message": "The operation 'Void' is not allowed on a Sale transaction with result 'Approved' and settlement state 'Settled'.", "details": "null", "data": { "correlationId": "0123456789abcdef0123456789abcdef" }, "validationErrors": "null" } } ``` ### 429 The request was refused because a rate limit was exceeded, or because something a later retry can clear stopped it. A rate limit refusal carries an `application/problem+json` body: wait at least the interval `Retry-After` names before retrying, then back off. Limits are tuned per deployment, so read the allowance from the response headers rather than assuming a fixed ceiling. Any other refusal carries the standard error envelope as `application/json`, and its `error.code` names the cause. **Content type:** `application/problem+json` Schema: [`RateLimitProblemDetails`](https://devportal.demo.winkpg.io/docs/api/models/RateLimitProblemDetails.md) Properties: - `type` (string) required: The problem type identifier. Always the same value: the failure is the status code itself, so there is no sub-type for a caller to branch on. (nullable) - `title` (string) required: A short, human-readable summary of the problem type. (nullable) - `status` (integer(int32)) required: The HTTP status code, repeated in the body as the problem-details format defines. - `detail` (string) required: A human-readable explanation of this occurrence of the problem. (nullable) - `retryAfterSeconds` (integer(int32)) required: How long to wait before retrying, in whole seconds, carrying the same figure as the `Retry-After` header. Always at least one: a value of zero would invite an immediate retry that is certain to be rejected again. **Content type:** `application/json` Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md) Properties: - `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md)) ## Example request Every block below sends the same request. Replace {{BASE_URL}} with the address of the API you are calling and {{API_KEY}} with your own key. The request body is a MerchantRegisterDto. See the Request body section below for its fields. ### cURL ```bash curl -X POST "{{BASE_URL}}/api/merchants/{id}/registers" \ -H "api-key: {{API_KEY}}" \ -H "Content-Type: application/json" \ -d '{ "friendlyId": "" }' ``` ### PowerShell ```powershell $headers = @{ 'api-key' = '{{API_KEY}}' } $body = @' { "friendlyId": "" } '@ $response = Invoke-RestMethod -Method POST -Uri '{{BASE_URL}}/api/merchants/{id}/registers' ` -Headers $headers -ContentType 'application/json' -Body $body ``` ### TypeScript (SDK) ```bash npm install @winkpg/winkpg-api ``` ```typescript import { Configuration, MerchantsApi } from '@winkpg/winkpg-api'; const api = new MerchantsApi(new Configuration({ basePath: '{{BASE_URL}}', apiKey: '{{API_KEY}}', })); const { data } = await api.registersSaveRegister("3fa85f64-5717-4562-b3fc-2c963f66afa6", { "friendlyId": "" }); ``` ### TypeScript (raw HTTP) ```typescript const response = await fetch('{{BASE_URL}}/api/merchants/{id}/registers', { method: 'POST', headers: { "api-key": "{{API_KEY}}", "Content-Type": "application/json", }, body: JSON.stringify({ "friendlyId": "" }), }); const data = await response.json(); ``` ### C# (SDK) ```bash dotnet add package WinkPg.Api.Client ``` ```csharp using WinkPg.Api.Client.Api; using WinkPg.Api.Client.Client; using System.Text.Json; var config = new Configuration { BasePath = "{{BASE_URL}}" }; config.AddApiKey("api-key", "{{API_KEY}}"); var api = new MerchantsApi(config); var body = JsonSerializer.Deserialize(""" { "friendlyId": "" } """); var result = await api.RegistersSaveRegisterAsync(Guid.Parse("3fa85f64-5717-4562-b3fc-2c963f66afa6"), body); ``` ### C# (raw HTTP) ```csharp using System.Text; using var http = new HttpClient { BaseAddress = new Uri("{{BASE_URL}}") }; var request = new HttpRequestMessage(new HttpMethod("POST"), "/api/merchants/{id}/registers"); request.Headers.Add("api-key", "{{API_KEY}}"); request.Content = new StringContent(""" { "friendlyId": "" } """, Encoding.UTF8, "application/json"); var response = await http.SendAsync(request); response.EnsureSuccessStatusCode(); var json = await response.Content.ReadAsStringAsync(); ``` ### Python (SDK) ```bash pip install winkpg-api ``` ```python import winkpg_api configuration = winkpg_api.Configuration(host="{{BASE_URL}}") configuration.api_key["ApiKey"] = "{{API_KEY}}" with winkpg_api.ApiClient(configuration) as client: api = winkpg_api.MerchantsApi(client) body = winkpg_api.MerchantRegisterDto.from_dict({ "friendlyId": "" }) result = api.registers_save_register("3fa85f64-5717-4562-b3fc-2c963f66afa6", body) ``` ### Python (raw HTTP) ```bash pip install requests ``` ```python import requests headers = { "api-key": "{{API_KEY}}", "Content-Type": "application/json", } body = { "friendlyId": "" } response = requests.request( "POST", "{{BASE_URL}}/api/merchants/{id}/registers", headers=headers, json=body, ) response.raise_for_status() data = response.json() ``` ## See also - [All documentation](https://devportal.demo.winkpg.io/llms.txt): the machine-readable index of every public page on this site.