core

README

Open Integration - a pipeline execution engine

stop using YAMLs

This is not production ready stuff

Until the project has not reached version > 1.x.x it may have breaking changes in the API, please use the latest version before opening issue.

Concepts

• A compiled, binray pipeline

• State - the engine holds the state of all the tasks

• Service - a standalone binary exposing API over http2 (gRPC) that the engine can trigger, called endpoint.

• Task - a request from a service to run some logic.

• Endpoint of a service defined by 2 files of JSON schema, arguments.json and returns.json, the engine will enforce the arguments given by a task and the output created to match the schema.

Example

Hello World

• Copy
• go mod init ...
• go mod tidy
• go run main.go

package main

import (
	"fmt"
	"os"

	"github.com/open-integration/core"
	"github.com/open-integration/core/pkg/state"
)

func main() {
	pipe := core.Pipeline{
		Metadata: core.PipelineMetadata{
			Name: "hello-world",
		},
		Spec: core.PipelineSpec{
			Reactions: []core.EventReaction{
				core.EventReaction{
					Condition: core.ConditionEngineStarted,
					Reaction: func(ev state.Event, state state.State) []core.Task {
						fmt.Println("Hello world")
						return []core.Task{}
					},
				},
			},
		},
	}
	e := core.NewEngine(&core.EngineOptions{
		Pipeline: pipe,
	})
	err := e.Run()
	if err != nil {
		fmt.Println(err.Error())
		os.Exit(1)
	}
}

Real world examples

• JIRA
• Trello

Documentation

Index

• func ConditionEngineStarted(ev state.Event, s state.State) bool
• func ConditionTaskFinished(task string) func(ev state.Event, s state.State) bool
• func ConditionTaskFinishedWithStatus(task string, status string) func(ev state.Event, s state.State) bool
• func HandleEngineError(err error)
• type Engine
  • func NewEngine(opt *EngineOptions) Engine
• type EngineKubernetesOptions
• type EngineOptions
• type EventReaction
• type Pipeline
• type PipelineMetadata
• type PipelineSpec
• type Service

Functions

func ConditionEngineStarted

func ConditionEngineStarted(ev state.Event, s state.State) bool

ConditionEngineStarted returns true once the engine emits started event

func ConditionTaskFinished

func ConditionTaskFinished(task string) func(ev state.Event, s state.State) bool

ConditionTaskFinished returns true once a task reached finished state

func ConditionTaskFinishedWithStatus

func ConditionTaskFinishedWithStatus(task string, status string) func(ev state.Event, s state.State) bool

ConditionTaskFinishedWithStatus returns true once a task is finished with given status

func HandleEngineError

func HandleEngineError(err error)

HandleEngineError prints the error in case the engine.Run was failed and exit

Types

type Engine

type Engine interface {
	Run() error
	Modem() modem.Modem
}

Engine exposes the interface of the engine

func NewEngine

func NewEngine(opt *EngineOptions) Engine

NewEngine create new engine

type EngineKubernetesOptions

type EngineKubernetesOptions struct {
	Path                string
	Context             string
	Namespace           string
	InCluster           bool
	Host                string
	B64Crt              string
	Token               string
	LogsVolumeClaimName string
	LogsVolumeName      string
}

EngineKubernetesOptions when running service on kubernetes cluster

type EngineOptions

type EngineOptions struct {
	Pipeline Pipeline
	// LogsDirectory path where to store logs
	LogsDirectory string
	Kubeconfig    *EngineKubernetesOptions
	Logger        logger.Logger
}

EngineOptions to create new engine

type EventReaction

type EventReaction struct {
	Condition func(ev state.Event, state state.State) bool
	Reaction  func(ev state.Event, state state.State) []task.Task
}

EventReaction is a binding of an event to a function that builds tasks

type Pipeline

type Pipeline struct {
	Metadata PipelineMetadata
	Spec     PipelineSpec
}

Pipeline is the pipeline representation

type PipelineMetadata

type PipelineMetadata struct {
	Name         string
	OS           string
	Architecture string
}

PipelineMetadata holds all the metadata of a pipeline

type PipelineSpec

type PipelineSpec struct {
	Reactions []EventReaction
	Services  []Service
}

PipelineSpec is the spec of a pipeline

type Service

type Service struct {
	// Name is official service which is part of the service catalog (https://github.com/open-integration/core-services/releases)
	Name string
	// Version of the service, empty string will use the latest version from catalog
	Version string
	// Path a location of the local fs the service can be found, Path cannot be set with Name together
	Path string
	// As alias name to refer the service as part of the task implementation
	As string
}

Service is a Service a pipeline should execute