Inngest Workflow Provider

The Inngest provider implements the workflow.WorkflowStore interface using Inngest’s HTTP API for persisting workflow state. Inngest is an event-driven durable execution platform that provides reliable state management, retries, and step functions. This provider stores and retrieves workflow state through the Inngest REST API.

Choose Inngest when you want event-driven workflow state persistence with a developer-friendly local dev server. Inngest provides reliable state management through a REST API, making it easy to integrate into serverless or event-driven architectures. For full orchestration with replay, consider Temporal. For simpler key-value persistence, consider NATS.

Installation

go get github.com/lookatitude/beluga-ai/workflow/providers/inngest

Start the Inngest dev server for local development:

npx inngest-cli@latest dev

Quick Start

package main

import (
    "context"
    "fmt"
    "log"

    "github.com/lookatitude/beluga-ai/workflow"
    "github.com/lookatitude/beluga-ai/workflow/providers/inngest"
)

func main() {
    store, err := inngest.New(inngest.Config{
        BaseURL:  "http://localhost:8288",
        EventKey: "my-event-key",
    })
    if err != nil {
        log.Fatal(err)
    }

    executor := workflow.NewExecutor(
        workflow.WithStore(store),
    )

    ctx := context.Background()

    handle, err := executor.Execute(ctx, myWorkflow, workflow.WorkflowOptions{
        ID:    "order-process-1",
        Input: "process payment",
    })
    if err != nil {
        log.Fatal(err)
    }

    result, err := handle.Result(ctx)
    if err != nil {
        log.Fatal(err)
    }
    fmt.Println("Result:", result)
}

func myWorkflow(ctx workflow.WorkflowContext, input any) (any, error) {
    return fmt.Sprintf("completed: %v", input), nil
}

Configuration

Parameter	Type	Default	Description
BaseURL	string	"http://localhost:8288"	Inngest API base URL
EventKey	string	""	Event key for API authentication
Client	inngest.HTTPClient	http.DefaultClient	Custom HTTP client

HTTPClient Interface

The provider accepts a custom HTTP client for advanced connection configuration or testing:

type HTTPClient interface {
    Do(req *http.Request) (*http.Response, error)
}

Custom HTTP Client

store, err := inngest.New(inngest.Config{
    BaseURL: "https://inngest.example.com",
    EventKey: os.Getenv("INNGEST_EVENT_KEY"),
    Client: &http.Client{
        Timeout: 30 * time.Second,
        Transport: &http.Transport{
            MaxIdleConns: 10,
        },
    },
})
if err != nil {
    log.Fatal(err)
}

API Reference

Save

func (s *Store) Save(ctx context.Context, state workflow.WorkflowState) error

Serializes workflow state to JSON and sends it to the Inngest API via PUT /v1/workflows/{workflowID}. The state is also cached in-memory for listing operations. Returns an error if WorkflowID is empty or if the API returns a 4xx/5xx status.

Load

func (s *Store) Load(ctx context.Context, workflowID string) (*workflow.WorkflowState, error)

Retrieves workflow state from the Inngest API via GET /v1/workflows/{workflowID}. Returns nil, nil if the workflow is not found (404 response).

List

func (s *Store) List(_ context.Context, filter workflow.WorkflowFilter) ([]workflow.WorkflowState, error)

Returns workflows from the in-memory cache. Since the Inngest API does not natively support listing, this returns only workflows that have been saved through this store instance. Supports filtering by Status and limiting results with Limit.

Delete

func (s *Store) Delete(ctx context.Context, workflowID string) error

Removes workflow state via DELETE /v1/workflows/{workflowID} and clears the in-memory cache entry. Returns successfully if the workflow was not found (404 is treated as success).

Authentication

When an EventKey is configured, it is sent as a Bearer token in the Authorization header on all API requests:

Authorization: Bearer <event-key>

For production Inngest deployments, set the event key via environment variable:

store, err := inngest.New(inngest.Config{
    BaseURL:  "https://api.inngest.com",
    EventKey: os.Getenv("INNGEST_EVENT_KEY"),
})

Error Handling

HTTP errors are reported with the status code for troubleshooting:

err := store.Save(ctx, state)
if err != nil {
    // Error format: "inngest/save: status 500"
    log.Printf("Failed to save: %v", err)
}

Listing Behavior

The List method returns workflows from an in-memory cache rather than querying the Inngest API. This means:

• Only workflows saved through this store instance are listed.
• The cache resets on process restart.
• Load always queries the Inngest API directly, providing accurate point-in-time state.