WebAPI

System Five Web API - The Legacy TServerMethodsWebAPI Surface
URL class: TServerMethodsWebAPI — /Windward/WebAPI/TServerMethodsWebAPI/... This is the original, largest and most heterogeneous part of the API: 60 publi...
Tue, 13 Oct, 2026 at 8:40 AM
System Five Web API - Invoices
URL class: Invoice — /Windward/WebAPI/Invoice/... Related legacy operations on TServerMethodsWebAPI (Insert_Full_Invoice, Invoices_Get, InvoiceLines_*, Cha...
Tue, 13 Oct, 2026 at 8:37 AM
System Five Web API - Customers
URL class: Customer — /Windward/WebAPI/Customer/... The older customer operations on TServerMethodsWebAPI (Get_Customers, List_Customers, Get_Customer_By_E...
Tue, 13 Oct, 2026 at 8:36 AM
System Five Web API - Inventory
URL class: Inventory — /Windward/WebAPI/Inventory/... The older parts operations on TServerMethodsWebAPI (Get_Parts, Get_Parts_V2, List_Parts, Parts_Read, ...
Tue, 13 Oct, 2026 at 8:34 AM
System Five Web API - AP Bills
URL class: APBill — /Windward/WebAPI/APBill/... The legacy equivalent is POST /TServerMethodsWebAPI/Insert_AP_Bill — see The Legacy TServerMethodsWebAPI Su...
Tue, 13 Oct, 2026 at 8:33 AM
System Five Web API - The Upsert Model
This is the single most important page in this guide, and the one thing Swagger cannot tell you. Read it before writing any code that POSTs. 1. add does n...
Tue, 13 Oct, 2026 at 8:32 AM
System Five Web API - Common Parameters
These parameters recur across many endpoints. Swagger lists them per operation but does not say how they behave, what happens when they are wrong, or how th...
Tue, 13 Oct, 2026 at 8:31 AM
System Five Web API - Response Envelopes and Error Semantics
Read Transport, URLs and Hosting first — in particular, the HTTP status code is always 200 except for authentication failures. Everything below is about fin...
Tue, 13 Oct, 2026 at 8:30 AM
System Five Web API - Transport, URLs and Hosting
This page covers what the Swagger document cannot express: how a URL is actually assembled, which host/port answers, and what the HTTP layer does to your re...
Tue, 13 Oct, 2026 at 8:30 AM
System Five Web API - Health, Readiness and Diagnostics
There are four different "is it working?" endpoints and they answer four different questions. Using the wrong one is the most common monitoring mi...
Tue, 13 Oct, 2026 at 8:29 AM


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