Merge pull request #2 from project-flogo/feature-microgateway

Feature microgateway

README.md

@@ -0,0 +1,14 @@
+# Microgateway Action
+This is a microgateway action which supports the conditional evaluation of activities. The microgateway has one setting: 'uri' which is the URL of the microgateway JSON resource.
+
+## Resource Schema
+
+The JSON Schema for the Microgateway resource can be found [here](https://github.com/project-flogo/microgateway/tree/master/internal/schema/schema.json).
+
+## Example Flogo JSON Usage of a Microgateway Action
+
+An example of a basic gateway can be found [here](https://github.com/project-flogo/microgateway/tree/master/examples/json/basic-gateway).
+
+## Example Flogo API Usage of a Microgateway Action
+
+An API example can be found [here](https://github.com/project-flogo/microgateway/tree/master/examples/api/basic-gateway).

action.go

@@ -0,0 +1,283 @@
+package microgateway
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+
+	_ "github.com/project-flogo/contrib/function"
+	"github.com/project-flogo/core/action"
+	"github.com/project-flogo/core/activity"
+	"github.com/project-flogo/core/app/resource"
+	"github.com/project-flogo/core/data/expression"
+	_ "github.com/project-flogo/core/data/expression/script"
+	"github.com/project-flogo/core/data/mapper"
+	"github.com/project-flogo/core/data/metadata"
+	"github.com/project-flogo/core/data/resolve"
+	"github.com/project-flogo/core/support/logger"
+	"github.com/project-flogo/microgateway/api"
+	"github.com/project-flogo/microgateway/internal/core"
+	_ "github.com/project-flogo/microgateway/internal/function"
+	"github.com/project-flogo/microgateway/internal/pattern"
+	"github.com/project-flogo/microgateway/internal/schema"
+)
+
+var log = logger.GetLogger("microgateway")
+
+// Action is the microgateway action
+type Action struct {
+	id           string
+	settings     Settings
+	microgateway *core.Microgateway
+}
+
+// Manager loads the microgateway definition resource
+type Manager struct {
+}
+
+func init() {
+	action.Register(&Action{}, &Factory{})
+	resource.RegisterLoader("microgateway", &Manager{})
+}
+
+var actionMetadata = action.ToMetadata(&Settings{}, &Input{}, &Output{})
+
+// LoadResource loads the microgateway definition
+func (m *Manager) LoadResource(config *resource.Config) (*resource.Resource, error) {
+	data := config.Data
+
+	err := schema.Validate(data)
+	if err != nil {
+		return nil, fmt.Errorf("error validating schema: %s", err.Error())
+	}
+
+	var definition *api.Microgateway
+	err = json.Unmarshal(data, &definition)
+	if err != nil {
+		return nil, fmt.Errorf("error marshalling microgateway definition resource with id '%s', %s", config.ID, err.Error())
+	}
+
+	return resource.New("microgateway", definition), nil
+}
+
+// Factory is a microgateway factory
+type Factory struct {
+	*resource.Manager
+}
+
+type initContext struct {
+	settings map[string]interface{}
+}
+
+func (i *initContext) Settings() map[string]interface{} {
+	return i.settings
+}
+
+func (i *initContext) MapperFactory() mapper.Factory {
+	return nil
+}
+
+func (f *Factory) Initialize(ctx action.InitContext) error {
+	f.Manager = ctx.ResourceManager()
+	return nil
+}
+
+// New creates a new microgateway
+func (f *Factory) New(config *action.Config) (action.Action, error) {
+	act := Action{
+		id: config.Id,
+	}
+	if act.id == "" {
+		act.id = config.Ref
+	}
+
+	if len(config.Data) > 0 {
+		err := json.Unmarshal(config.Data, &config.Settings)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	err := metadata.MapToStruct(config.Settings, &act.settings, true)
+	if err != nil {
+		return nil, err
+	}
+
+	var actionData *api.Microgateway
+	if uri := act.settings.URI; uri != "" {
+		if resData := api.GetResource(uri); resData != nil {
+			actionData = resData
+		} else {
+			// Load action data from resources
+			resData := f.Manager.GetResource(uri)
+			if resData == nil {
+				return nil, fmt.Errorf("failed to load microgateway URI data: '%s'", config.Id)
+			}
+			actionData = resData.Object().(*api.Microgateway)
+		}
+	} else if p := act.settings.Pattern; p != "" {
+		definition, err := pattern.Load(p)
+		if err != nil {
+			return nil, err
+		}
+		actionData = definition
+	} else {
+		return nil, errors.New("no definition found for microgateway")
+	}
+
+	services := make(map[string]*core.Service, len(actionData.Services))
+	for i := range actionData.Services {
+		name := actionData.Services[i].Name
+		if _, ok := services[name]; ok {
+			return nil, fmt.Errorf("duplicate service name: %s", name)
+		}
+
+		if ref := actionData.Services[i].Ref; ref != "" {
+			if factory := activity.GetFactory(ref); factory != nil {
+				actvt, err := factory(&initContext{settings: actionData.Services[i].Settings})
+				if err != nil {
+					return nil, err
+				}
+				services[name] = &core.Service{
+					Name:     name,
+					Settings: actionData.Services[i].Settings,
+					Activity: actvt,
+				}
+				continue
+			}
+			actvt := activity.Get(ref)
+			if actvt == nil {
+				return nil, fmt.Errorf("can't find activity %s", ref)
+			}
+			services[name] = &core.Service{
+				Name:     name,
+				Settings: actionData.Services[i].Settings,
+				Activity: actvt,
+			}
+		} else if handler := actionData.Services[i].Handler; handler != nil {
+			services[name] = &core.Service{
+				Name:     name,
+				Settings: actionData.Services[i].Settings,
+				Activity: &core.Adapter{Handler: handler},
+			}
+		} else {
+			return nil, fmt.Errorf("no ref or handler for service: %s", name)
+		}
+	}
+
+	expressionFactory := expression.NewFactory(resolve.GetBasicResolver())
+	getExpression := func(value interface{}) (*core.Expr, error) {
+		if stringValue, ok := value.(string); ok && len(stringValue) > 0 && stringValue[0] == '=' {
+			expr, err := expressionFactory.NewExpr(stringValue[1:])
+			if err != nil {
+				return nil, err
+			}
+			return core.NewExpr(stringValue, expr), nil
+		}
+		return core.NewExpr(fmt.Sprintf("%v", value), expression.NewLiteralExpr(value)), nil
+	}
+
+	steps, responses := actionData.Steps, actionData.Responses
+	microgateway := core.Microgateway{
+		Name:          actionData.Name,
+		Async:         act.settings.Async,
+		Steps:         make([]core.Step, len(steps)),
+		Responses:     make([]core.Response, len(responses)),
+		Configuration: config.Settings,
+	}
+	for j := range steps {
+		if condition := steps[j].Condition; condition != "" {
+			expr, err := expressionFactory.NewExpr(condition)
+			if err != nil {
+				log.Infof("condition parsing error: %s", condition)
+				return nil, err
+			}
+			microgateway.Steps[j].Condition = core.NewExpr(condition, expr)
+		}
+
+		service := services[steps[j].Service]
+		if service == nil {
+			return nil, fmt.Errorf("service not found: %s", steps[j].Service)
+		}
+		microgateway.Steps[j].Service = service
+
+		input := steps[j].Input
+		inputExpression := make(map[string]*core.Expr, len(input))
+		for key, value := range input {
+			inputExpression[key], err = getExpression(value)
+			if err != nil {
+				return nil, err
+			}
+		}
+		microgateway.Steps[j].Input = inputExpression
+
+		if condition := steps[j].HaltCondition; condition != "" {
+			expr, err := expressionFactory.NewExpr(condition)
+			if err != nil {
+				log.Infof("halt condition parsing error: %s", condition)
+				return nil, err
+			}
+			microgateway.Steps[j].HaltCondition = core.NewExpr(condition, expr)
+		}
+	}
+
+	for j := range responses {
+		if condition := responses[j].Condition; condition != "" {
+			expr, err := expressionFactory.NewExpr(condition)
+			if err != nil {
+				log.Infof("condition parsing error: %s", condition)
+				return nil, err
+			}
+			microgateway.Responses[j].Condition = core.NewExpr(condition, expr)
+		}
+
+		microgateway.Responses[j].Error = responses[j].Error
+
+		microgateway.Responses[j].Output.Code, err = getExpression(responses[j].Output.Code)
+		if err != nil {
+			return nil, err
+		}
+
+		data := responses[j].Output.Data
+		if hashMap, ok := data.(map[string]interface{}); ok {
+			dataExpressions := make(map[string]*core.Expr, len(hashMap))
+			for key, value := range hashMap {
+				dataExpressions[key], err = getExpression(value)
+				if err != nil {
+					return nil, err
+				}
+			}
+			microgateway.Responses[j].Output.Datum = dataExpressions
+		} else {
+			microgateway.Responses[j].Output.Data, err = getExpression(data)
+			if err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	act.microgateway = &microgateway
+
+	return &act, nil
+}
+
+// Metadata returns the metadata for the microgateway
+func (a *Action) Metadata() *action.Metadata {
+	return actionMetadata
+}
+
+// IOMetadata returns the iometadata for the microgateway
+func (a *Action) IOMetadata() *metadata.IOMetadata {
+	return actionMetadata.IOMetadata
+}
+
+// Run executes the microgateway
+func (a *Action) Run(ctx context.Context, input map[string]interface{}) (map[string]interface{}, error) {
+	code, mData, err := core.Execute(a.id, input, a.microgateway, a.IOMetadata())
+	output := make(map[string]interface{}, 8)
+	output["code"] = code
+	output["data"] = mData
+
+	return output, err
+}

action.json

@@ -0,0 +1,9 @@
+{
+  "name": "microgateway",
+  "type": "flogo:action",
+  "ref": "github.com/project-flogo/microgateway",
+  "version": "0.0.1",
+  "title": "Microgateway Action",
+  "description": "Action implementing the microgateway features.",
+  "homepage": "https://github.com/project-flogo/microgateway"
+}