FD1 Client Protocol
 
Library Developer Home FD1 Client Protocol Home Concepts Reading Data Writing Data Protocol Defined Servers Connect & Authenticate Proxies & Tunnels
Webhooks & Firehoses Programming Support Logging Minor Facts State Facts Response Format How To Guides eCommerce Sites Custom Point of Sale Customer Access Bulk Downloads Major APIs / Endpoints All Endpoints Products Sales SalesBuilder Session Get Attribute Sale Capture General Purpose Data Capture Devices Barcode Scanners Eftpos IoT Sensors Power Outlets Printing Scales Security Cameras Purchasing / Supply Side Purchase Orders Invoices Invoice Payments Document Capture Rare APIs / Endpoints SSL Certificates API Key Management Diagnositics PosGreen Server to Client Messages Overview Resources / Objects Purchase Order Invoice Payable Invoice Payment Product Supplier Location Sale Lines Sale Delivery Details Sales Price Maps Employees Carriers Payments Product Kits Department 1 Customers

FD1 Server Messages

A Server message is where the FD1 server sends a message to the client that might be unexpected or out of bound. For example a server might send a message advising it is going to close the websocket shortly.

Most activity is driven from the client, your end, and the server responds. This can be a single request-response, or multiple responses request-response/response/response.

A server generated message uses a request packet, and the "a" field starts with "fn1."

{
a: "fn1.link.link_status",
  v: {
    message: "Server is powering down in 15 minutes",
    ...
  }
}

Websocket/Link Advisory Messages

These messages are sent to advise the status of the overall network connecton.

Fields present in "v"

NameDescriptonExample
messageA message broadcast that should ideally be displayed to the end user."Store is closing in 15 minutes"
servers An array of alternative server URLs that can be used instead of the current server. [ { url: "wss://anotherserver.local/usefd1" } ]