Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/cschleiden/go-workflows
Embedded durable workflows for Golang similar to DTFx/Cadence/Temporal
https://github.com/cschleiden/go-workflows
durabletask go golang orchestration workflow workflows
Last synced: 7 days ago
JSON representation
Embedded durable workflows for Golang similar to DTFx/Cadence/Temporal
- Host: GitHub
- URL: https://github.com/cschleiden/go-workflows
- Owner: cschleiden
- License: mit
- Created: 2021-12-02T20:33:40.000Z (almost 3 years ago)
- Default Branch: main
- Last Pushed: 2024-05-17T04:42:49.000Z (6 months ago)
- Last Synced: 2024-05-17T22:26:44.425Z (6 months ago)
- Topics: durabletask, go, golang, orchestration, workflow, workflows
- Language: Go
- Homepage: https://cschleiden.github.io/go-workflows/
- Size: 8.07 MB
- Stars: 166
- Watchers: 7
- Forks: 42
- Open Issues: 18
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# Durable workflows using Go
[](https://github.com/cschleiden/go-workflows/actions/workflows/go.yml)
Borrows heavily from [Temporal](https://github.com/temporalio/temporal) (and since it's a fork also [Cadence](https://github.com/uber/cadence)) as well as [DTFx](https://github.com/Azure/durabletask).
See also:
- https://cschleiden.dev/blog/2022-02-13-go-workflows-part1/
- https://cschleiden.dev/blog/2022-05-02-go-workflows-part2/
## Docs
See http://cschleiden.github.io/go-workflows for the current version of the documentation.
## Simple example
### Workflow
Workflows are written in Go code. The only exception is they must not use any of Go's non-deterministic features (`select`, iteration over a `map`, etc.). Inputs and outputs for workflows and activities have to be serializable:
```go
func Workflow1(ctx workflow.Context, input string) error {
r1, err := workflow.ExecuteActivity[int](ctx, workflow.DefaultActivityOptions, Activity1, 35, 12).Get(ctx)
if err != nil {
panic("error getting activity 1 result")
}
log.Println("A1 result:", r1)
r2, err := workflow.ExecuteActivity[int](ctx, workflow.DefaultActivityOptions, Activity2).Get(ctx)
if err != nil {
panic("error getting activity 1 result")
}
log.Println("A2 result:", r2)
return nil
}
```
### Activities
Activities can have side-effects and don't have to be deterministic. They will be executed only once and the result is persisted:
```go
func Activity1(ctx context.Context, a, b int) (int, error) {
return a + b, nil
}
func Activity2(ctx context.Context) (int, error) {
return 12, nil
}
```
### Worker
The worker is responsible for executing `Workflows` and `Activities`, both need to be registered with it.
```go
func runWorker(ctx context.Context, mb backend.Backend) {
w := worker.New(mb, nil)
w.RegisterWorkflow(Workflow1)
w.RegisterActivity(Activity1)
w.RegisterActivity(Activity2)
if err := w.Start(ctx); err != nil {
panic("could not start worker")
}
}
```
### Backend
The backend is responsible for persisting the workflow events. Currently there is an in-memory backend implementation for testing, one using [SQLite](http://sqlite.org), one using MySql, and one using Redis.
```go
b := sqlite.NewSqliteBackend("simple.sqlite")
```
### Putting it all together
We can start workflows from the same process the worker runs in -- or they can be separate. Here we use the SQLite backend, spawn a single worker (which then executes both `Workflows` and `Activities`), and then start a single instance of our workflow
```go
func main() {
ctx := context.Background()
b := sqlite.NewSqliteBackend("simple.sqlite")
go runWorker(ctx, b)
c := client.New(b)
wf, err := c.CreateWorkflowInstance(ctx, client.WorkflowInstanceOptions{
InstanceID: uuid.NewString(),
}, Workflow1, "input-for-workflow")
if err != nil {
panic("could not start workflow")
}
c2 := make(chan os.Signal, 1)
signal.Notify(c2, os.Interrupt)
<-c2
}
```