ReferencesTypeScript SDK

Referencing functions

Using step.invoke(), you can directly call one Inngest function from another and handle the result. You can use this with referenceFunction to call Inngest functions located in other apps, or to avoid importing dependencies of functions within the same app.

// @/inngest/compute.ts
import { referenceFunction } from "inngest";
import { z } from "zod";
import { type computePi } from "@/inngest/computePi";

// Create a local reference to a function without importing dependencies
export const computePi = referenceFunction<typeof computePi>({
  functionId: "compute-pi",
});

// Create a reference to a function in another application
export const computeSquare = referenceFunction({
  appId: "my-python-app",
  functionId: "compute-square",
  // Schemas are optional, but provide types for your call if specified
  schemas: {
    data: z.object({
      number: z.number(),
    }),
    return: z.object({
      result: z.number(),
    }),
  },
});

// @/inngest/someFn.ts
import { computeSquare } from "@/inngest/compute"; // import the referenece

// square.result is typed as a number
const square = await step.invoke("compute-square-value", {
  function: computeSquare,
  data: { number: 4 }, // input data is typed, requiring input if it's needed
});

How to use referenceFunction

The simplest reference just contains a functionId. When used, this will invoke the function with the given ID in the same app that is used to invoke it.

The input and output types are unknown.

import { referenceFunction } from "inngest";

await step.invoke("start-process", {
  function: referenceFunction({
    functionId: "some-fn",
  }),
});

If referencing a function in a different application, specify an appId too:

import { referenceFunction } from "inngest";

await step.invoke("start-process", {
  function: referenceFunction({
    functionId: "some-fn",
    appId: "some-app",
  }),
});

You can optionally provide schemas, which are a collection of Zod schemas used to provide typing to the input and output of the referenced function.

In the future, this will also validate the input and output.

import { referenceFunction } from "inngest";
import { z } from "zod";

await step.invoke("start-process", {
  function: referenceFunction({
    functionId: "some-fn",
    appId: "some-app",
    schemas: {
      data: z.object({
        foo: z.string(),
      }),
      return: z.object({
        success: z.boolean(),
      }),
    },
  }),
});

Even if functions are within the same app, this can also be used to avoid importing the dependencies of one function into another, which is useful for frameworks like Next.js where edge and serverless logic can be colocated but require different dependencies.

import { referenceFunction } from "inngest";
import { type someInngestFn } from "@/inngest/someFn"; // import only the type

await step.invoke("start-process", {
  function: referenceFunction<typeof someInngestFn>({
    functionId: "some-fn",
  }),
});

Configuration

  • Name
    functionId
    Type
    string
    Required
    required
    Description

    The ID of the function to reference. This can be either a local function ID or the ID of a function that exists in another app.

    If the latter, appId must also be provided. If appId is not provided, the function ID will be assumed to be a local function ID (the app ID of the calling app will be used).

  • Name
    appId
    Type
    string
    Required
    optional
    Description

    The ID of the app that the function belongs to. This is only required if the function being refenced exists in another app.

  • Name
    schemas
    Type
    object
    Required
    optional
    Description

    The schemas of the referenced function, providing typing to the input data and return of invoking the referenced function.

    If not provided and a local function type is not being passed as a generic into referenceFunction(), the schemas will be inferred as unknown.

    Properties
    • Name
      data
      Type
      zod
      Required
      optional
      Description

      The Zod schema to use to provide typing to the data payload required by the referenced function.

    • Name
      return
      Type
      zod
      Required
      optional
      Description

      The Zod schema to use to provide typing to the return value of the referenced function when invoked.