Refactor: lookup command

1 files changed, 59 insertions, 29 deletions

diff --git a/lib/instance.go b/lib/instance.go
index 0a16442e..d2f5e00b 100644
--- a/lib/instance.go
+++ b/lib/instance.go
@@ -9,21 +9,31 @@ import (
 	"github.com/tailscale/hujson"
 )
 
-type Instance struct {
-	config *config
+type Instance interface {
+	InitConfig(configFile string) error
+	InitConfigFromBytes(content []byte) error
+	AddInput(InputConverter)
+	AddOutput(OutputConverter)
+	ResetInput()
+	ResetOutput()
+	RunInput(Container) error
+	RunOutput(Container) error
+	Run() error
+}
+
+type instance struct {
 	input  []InputConverter
 	output []OutputConverter
 }
 
-func NewInstance() (*Instance, error) {
-	return &Instance{
-		config: new(config),
+func NewInstance() (Instance, error) {
+	return &instance{
 		input:  make([]InputConverter, 0),
 		output: make([]OutputConverter, 0),
 	}, nil
 }
 
-func (i *Instance) Init(configFile string) error {
+func (i *instance) InitConfig(configFile string) error {
 	var content []byte
 	var err error
 	configFile = strings.TrimSpace(configFile)
@@ -36,50 +46,48 @@ func (i *Instance) Init(configFile string) error {
 		return err
 	}
 
+	return i.InitConfigFromBytes(content)
+}
+
+func (i *instance) InitConfigFromBytes(content []byte) error {
+	config := new(config)
+
 	// Support JSON with comments and trailing commas
 	content, _ = hujson.Standardize(content)
 
-	if err := json.Unmarshal(content, &i.config); err != nil {
+	if err := json.Unmarshal(content, &config); err != nil {
 		return err
 	}
 
-	for _, input := range i.config.Input {
+	for _, input := range config.Input {
 		i.input = append(i.input, input.converter)
 	}
 
-	for _, output := range i.config.Output {
+	for _, output := range config.Output {
 		i.output = append(i.output, output.converter)
 	}
 
 	return nil
 }
 
-func (i *Instance) InitFromBytes(content []byte) error {
-	// Support JSON with comments and trailing commas
-	content, _ = hujson.Standardize(content)
-
-	if err := json.Unmarshal(content, &i.config); err != nil {
-		return err
-	}
-
-	for _, input := range i.config.Input {
-		i.input = append(i.input, input.converter)
-	}
+func (i *instance) AddInput(ic InputConverter) {
+	i.input = append(i.input, ic)
+}
 
-	for _, output := range i.config.Output {
-		i.output = append(i.output, output.converter)
-	}
+func (i *instance) AddOutput(oc OutputConverter) {
+	i.output = append(i.output, oc)
+}
 
-	return nil
+func (i *instance) ResetInput() {
+	i.input = make([]InputConverter, 0)
 }
 
-func (i *Instance) Run() error {
-	if len(i.input) == 0 || len(i.output) == 0 {
-		return errors.New("input type and output type must be specified")
-	}
+func (i *instance) ResetOutput() {
+	i.output = make([]OutputConverter, 0)
+}
 
+func (i *instance) RunInput(container Container) error {
 	var err error
-	container := NewContainer()
 	for _, ic := range i.input {
 		container, err = ic.Input(container)
 		if err != nil {
@@ -87,6 +95,10 @@ func (i *Instance) Run() error {
 		}
 	}
 
+	return nil
+}
+
+func (i *instance) RunOutput(container Container) error {
 	for _, oc := range i.output {
 		if err := oc.Output(container); err != nil {
 			return err
@@ -95,3 +107,21 @@ func (i *Instance) Run() error {
 
 	return nil
 }
+
+func (i *instance) Run() error {
+	if len(i.input) == 0 || len(i.output) == 0 {
+		return errors.New("input type and output type must be specified")
+	}
+
+	container := NewContainer()
+
+	if err := i.RunInput(container); err != nil {
+		return err
+	}
+
+	if err := i.RunOutput(container); err != nil {
+		return err
+	}
+
+	return nil
+}