How to integrate SAP Business One with Medusa

Does Medusa have an SAP Business One connector?

Medusa has no first-party SAP Business One connector and no SAP Business One guide. You integrate SAP Business One by writing a custom Medusa module that calls the SAP Business One Service Layer, then running it from workflows, subscribers, and scheduled jobs. The general Medusa ERP integration recipe shows each of these patterns with example code. Everything SAP-specific in this entry is Custom work.

Which SAP Business One API to use from Medusa

The SAP Business One Service Layer is a web API server that exposes SAP Business One business objects over HTTP and OData. It is the API to call from a Node.js application like Medusa.

• Protocol. OData version 3 at Copy to clipboard/b1s/v1 and OData version 4 at Copy to clipboard/b1s/v2. Both support CRUD with GET, POST, PATCH, and DELETE, plus OData query options such as Copy to clipboard$filter, Copy to clipboard$select, and Copy to clipboard$top.
• Session login. You POST Copy to clipboardCompanyDB, Copy to clipboardUserName, and Copy to clipboardPassword to Copy to clipboard/b1s/v1/Login. The response sets a Copy to clipboardB1SESSION cookie that you send on every later request. The sample session timeout is 30 minutes, so your module must log in again when a session expires.
• Batch. The Service Layer supports batch requests, which helps when you sync many items at once.
• Webhooks. As of SAP Business One 10.0 FP 2602, the Service Layer supports webhooks. You enable them per company, create an event subscription (for example, on Copy to clipboardOrders created), and the Webhook Messenger Service delivers notifications with retries.

The Service Layer runs on your SAP Business One server; SAP's examples use port 50000. Your Medusa backend needs network access to it, and SAP needs network access to Medusa if you use webhooks.

How SAP Business One data maps to Medusa

Each row is a sync you build in your SAP Business One module. The Medusa side of every row uses native commerce modules.

Store the SAP key, such as Copy to clipboardItemCode or Copy to clipboardCardCode, on the Medusa record, for example in Copy to clipboardmetadata or the product's Copy to clipboardexternal_id, so later syncs can match records.

Real-time vs scheduled sync with SAP Business One

Medusa supports both timing models with built-in tools. Your SAP Business One version decides how SAP changes reach Medusa.

• Real-time, Medusa to SAP. A subscriber on Copy to clipboardorder.placed runs a workflow that creates the sales order through the Service Layer.
• Real-time, inside checkout. A workflow hook on Copy to clipboardaddToCartWorkflow checks warehouse stock or purchase rules in SAP before an item enters the cart.
• Real-time, SAP to Medusa. On 10.0 FP 2602 or later, a Service Layer webhook posts to a custom Medusa API route that runs an update workflow.
• Scheduled. On older versions, or for full catalog and price refreshes, a scheduled job polls the Service Layer on a cron schedule.

Code skeleton: a Service Layer client in a Medusa module

A Medusa module service holds the connection logic, and workflows resolve it from the Medusa container. This sketch logs in and reuses the Copy to clipboardB1SESSION cookie. Add re-login on 401, error handling, and the item, price, and order methods you need.

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type Options = { url: string; companyDb: string; user: string; password: string }

export default class SapB1ModuleService {
  private options: Options
  private session?: string

  constructor({}, options: Options) {
    this.options = options
  }

  private async login() {
    const res = await fetch(`${this.options.url}/b1s/v1/Login`, {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({
        CompanyDB: this.options.companyDb,
        UserName: this.options.user,
        Password: this.options.password,
      }),
    })

Register the module in Copy to clipboardmedusa-config.ts as described in Modules. Wrap writes to SAP, such as creating a sales order, in a workflow step with a compensation function that cancels the SAP document if a later step fails.

How Medusa compares with prebuilt SAP Business One connectors

A prebuilt connector or iPaaS tool runs the sync outside the store. Medusa runs the integration inside its own backend instead.

When Medusa is not the right choice for SAP Business One

• A prebuilt connector already covers your flows for the platform you run, and you have no developer. A Medusa SAP integration is TypeScript code your team maintains through SAP feature packs.
• Your Service Layer is not reachable from where Medusa runs and you cannot expose it. Every pattern above depends on that connection.

Medusa fits when SAP Business One holds rules the storefront must enforce live, such as business partner special prices, warehouse stock, or who may buy which items.