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Building a Camunda 8 connector from an OpenAPI spec

By BPMN Kit · July 6, 2026

BPMN Kit ships 116 pre-built Camunda 8 connectors for common services, but internal APIs and less common third-party services won’t be in that catalog. If the API has an OpenAPI (Swagger) spec, @bpmnkit/connector-gen can generate a Camunda 8 connector element template from it directly — no manual property-by-property template authoring.

Generating from a spec

import { generateFromUrl } from "@bpmnkit/connector-gen";

const { templates } = await generateFromUrl(
  "https://api.example.com/openapi.json",
  {
    idPrefix: "com.mycompany",   // reverse-DNS prefix for generated template IDs
    filter: "^(createOrder|getOrder|cancelOrder)$", // only these operationIds
  },
);

// `templates` is an array of Camunda 8 element templates — one per matched operation

Each generated template becomes a selectable connector in a BPMN editor’s palette, with typed input fields derived from the OpenAPI spec’s request schema — path/query parameters, headers, and request body fields all become configurable properties on the resulting service task, the same way a hand-authored Camunda connector template would.

Generating from a spec you already have locally

If the spec is a local file rather than a URL, generate() takes the spec text directly:

import { readFileSync } from "node:fs";
import { generate } from "@bpmnkit/connector-gen";

const specText = readFileSync("./openapi.json", "utf-8");
const templates = generate(specText, { idPrefix: "com.mycompany" });

Writing templates to disk

Both functions can write the generated templates as files instead of (or as well as) returning them in memory — pass outputDir, and optionally format: "one-per-op" to get one file per operation rather than a single array file:

const { templates, files } = await generateFromUrl(specUrl, {
  idPrefix: "com.mycompany",
  outputDir: "./connector-templates",
  format: "one-per-op",
});

Auth detection

@bpmnkit/connector-gen inspects the spec’s securitySchemes and picks a sensible default auth type (API key, Bearer, Basic, OAuth2 client credentials) automatically — override it with defaultAuthType if the spec’s security definitions don’t match what you actually want the generated template to expose.

Applying a generated template to a process

Once generated, a template is applied the same way as any bundled connector — see applying connectors for the pattern using applyConnectorTemplate() against the bundled catalog; a generated template plugs into the same applyElementTemplate() call.

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