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1 month ago
2
Small, pragmatic workflow engine for Go with a built-in web console. Define workflows in Go, persist their execution, and observe/operate them via the web UI.
- Define workflows in Go using a state-machine approach
- each function is idempotent and can be retried
- Persistent storage (Postgres, SQLite, Mysql supported) with action history
- Concurrent execution with executor registration, heartbeats, and stuck-workflow repair
- Web console (dashboard, search, definitions with diagrams, executors, details)
- Mermaid-like flow visualization generated from workflow definitions
- Container-friendly, single-binary deployment
Prerequisites:
- Go 1.24+ (or Docker if you prefer containers)
This starts the demo application with a SQLite database, there are two workflows
-
DemoWorkflow - does some ficticious steps and adds some variables
-
GetIpWorkflow - gets the current public IP address from ifconfig.io and puts it into a state variable
docker run -p 8080:8080 \ -e GFLOW_DATABASE_TYPE=SQLLITE\ -e GFLOW_DATABASE_SQLLITE_FILE_NAME=/data/gflow.db\ -v "$(pwd):/data"\ --security-opt seccomp=unconfined \ juliangpurse/gopherflow:1.1.1
note the --security-opt seccomp=unconfined is required because of sqllite being run in a container
Access the web console at http://localhost:8080/
Username : admin
Password : admin
refer to the example application: https://github.com/RealZimboGuy/gopherflow-examples
go get github.com/RealZimboGuy/[email protected]
a struct that extends the base
type GetIpWorkflow struct {
core.BaseWorkflow
}
the workflow interface must be fully implemented
type Workflow interface {
StateTransitions() map[string][]string // map of state name -> list of next state names
InitialState() string // where to start
Description() string
Setup(wf *domain.Workflow)
GetWorkflowData() *domain.Workflow
GetStateVariables() map[string]string
GetAllStates() []models.WorkflowState
GetRetryConfig() models.RetryConfig
}
import (
"github.com/RealZimboGuy/gopherflow/pkg/gopherflow/core"
domain "github.com/RealZimboGuy/gopherflow/pkg/gopherflow/domain"
models "github.com/RealZimboGuy/gopherflow/pkg/gopherflow/models"
"io"
"log/slog"
"net/http"
"time"
)
// Define a named string type
var StateStart string = "Start"
var StateGetIpData string = "StateGetIpData"
const VAR_IP = "ip"
type GetIpWorkflow struct {
core.BaseWorkflow
}
func (m *GetIpWorkflow) Setup(wf *domain.Workflow) {
m.BaseWorkflow.Setup(wf)
}
func (m *GetIpWorkflow) GetWorkflowData() *domain.Workflow {
return m.WorkflowState
}
func (m *GetIpWorkflow) GetStateVariables() map[string]string {
return m.StateVariables
}
func (m *GetIpWorkflow) InitialState() string {
return StateStart
}
func (m *GetIpWorkflow) Description() string {
return "This is a Demo Workflow showing how it can be used"
}
func (m *GetIpWorkflow) GetRetryConfig() models.RetryConfig {
return models.RetryConfig{
MaxRetryCount: 10,
RetryIntervalMin: time.Second * 10,
RetryIntervalMax: time.Minute * 60,
}
}
func (m *GetIpWorkflow) StateTransitions() map[string][]string {
return map[string][]string{
StateStart: []string{StateGetIpData}, // Init -> StateGetIpData
StateGetIpData: []string{StateFinish}, // StateGetIpData -> finish
}
}
func (m *GetIpWorkflow) GetAllStates() []models.WorkflowState {
states := []models.WorkflowState{
{Name: StateStart, StateType: models.StateStart},
{Name: StateGetIpData, StateType: models.StateNormal},
{Name: StateFinish, StateType: models.StateEnd},
}
return states
}
// Each method returns the next state
func (m *GetIpWorkflow) Start() (*models.NextState, error) {
slog.Info("Starting workflow")
return &models.NextState{
Name: StateGetIpData,
ActionLog: "using ifconfig.io to return the public IP address",
}, nil
}
func (m *GetIpWorkflow) StateGetIpData() (*models.NextState, error) {
resp, err := http.Get("http://ifconfig.io")
if err != nil {
return nil, err
}
defer resp.Body.Close()
ipBytes, err := io.ReadAll(resp.Body)
if err != nil {
return nil, err
}
ip := string(ipBytes)
m.StateVariables[VAR_IP] = ip
return &models.NextState{
Name: StateFinish,
}, nil
}
import (
"log/slog"
"reflect"
"github.com/RealZimboGuy/gopherflow/pkg/gopherflow"
"github.com/RealZimboGuy/gopherflow_example/internal/workflows"
)
func main() {
//you may do your own logger setup here or use this default one with slog
gopherflow.SetupLogger()
gopherflow.WorkflowRegistry = map[string]func() core.Workflow{
"DemoWorkflow": func() core.Workflow {
return &workflows.DemoWorkflow{}
},
"GetIpWorkflow": func() core.Workflow {
// You can inject dependencies here
return &workflows.GetIpWorkflow{
// HTTPClient: httpClient,
// MyService: myService,
}
},
}
//uses the defaul ServeMux
app := gopherflow.Setup()
if err := app.Run(); err != nil {
slog.Error("Engine exited with error", "error", err)
}
}
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