Getting Started

Here are two example on how to use the library.

Hello World Example

Assuming this simple 'Hello World' BPMN example should just print "hello world". \

Then a simple (and verbose) code to execute this looks like this

package main

import (
    "fmt"

    "github.com/nitram509/lib-bpmn-engine/pkg/bpmn_engine"
)

func main() {
    // create a new named engine
    bpmnEngine := bpmn_engine.New()
    // basic example loading a BPMN from file,
    process, err := bpmnEngine.LoadFromFile("simple_task.bpmn")
    if err != nil {
        panic("file \"simple_task.bpmn\" can't be read.")
    }
    // register a handler for a service task by defined task id (there are alternative options for types as well)
    bpmnEngine.NewTaskHandler().Id("hello-world").Handler(printContextHandler)
    // setup some variables
    variables := map[string]interface{}{}
    variables["foo"] = "bar"
    // and execute the process
    bpmnEngine.CreateAndRunInstance(process.ProcessKey, variables)
}

func printContextHandler(job bpmn_engine.ActivatedJob) {
    println("< Hello World >")
    println(fmt.Sprintf("ElementId                = %s", job.ElementId()))
    println(fmt.Sprintf("BpmnProcessId            = %s", job.BpmnProcessId()))
    println(fmt.Sprintf("ProcessDefinitionKey     = %d", job.ProcessDefinitionKey()))
    println(fmt.Sprintf("ProcessDefinitionVersion = %d", job.ProcessDefinitionVersion()))
    println(fmt.Sprintf("CreatedAt                = %s", job.CreatedAt()))
    println(fmt.Sprintf("Variable 'foo'           = %s", job.Variable("foo")))
    job.Complete() // don't forget this one, or job.Fail("foobar")
}