Merge pull request #55 from owenfarrell/command

Extract business logic to base package

check/main.go

@@ -4,9 +4,8 @@ import (
 	"encoding/json"
 	"fmt"
 	"os"
-	"time"
 
-	"github.com/concourse/time-resource/lord"
+	resource "github.com/concourse/time-resource"
 	"github.com/concourse/time-resource/models"
 )
 
@@ -19,38 +18,13 @@ func main() {
 		os.Exit(1)
 	}
 
-	err = request.Source.Validate()
+	command := resource.CheckCommand{}
+
+	versions, err := command.Run(request)
 	if err != nil {
-		fmt.Fprintln(os.Stderr, "invalid configuration:", err)
+		fmt.Fprintln(os.Stderr, "running command:", err.Error())
 		os.Exit(1)
 	}
 
-	previousTime := request.Version.Time
-	currentTime := time.Now().UTC()
-
-	specifiedLocation := request.Source.Location
-	if specifiedLocation != nil {
-		currentTime = currentTime.In((*time.Location)(specifiedLocation))
-	}
-
-	tl := lord.TimeLord{
-		PreviousTime: previousTime,
-		Location:     specifiedLocation,
-		Start:        request.Source.Start,
-		Stop:         request.Source.Stop,
-		Interval:     request.Source.Interval,
-		Days:         request.Source.Days,
-	}
-
-	versions := []models.Version{}
-
-	if !previousTime.IsZero() {
-		versions = append(versions, models.Version{Time: previousTime})
-	}
-
-	if tl.Check(currentTime) {
-		versions = append(versions, models.Version{Time: currentTime})
-	}
-
 	json.NewEncoder(os.Stdout).Encode(versions)
 }

check_command.go

@@ -0,0 +1,47 @@
+package resource
+
+import (
+	"time"
+
+	"github.com/concourse/time-resource/lord"
+	"github.com/concourse/time-resource/models"
+)
+
+type CheckCommand struct {
+}
+
+func (*CheckCommand) Run(request models.CheckRequest) ([]models.Version, error) {
+	err := request.Source.Validate()
+	if err != nil {
+		return nil, err
+	}
+
+	previousTime := request.Version.Time
+	currentTime := time.Now().UTC()
+
+	specifiedLocation := request.Source.Location
+	if specifiedLocation != nil {
+		currentTime = currentTime.In((*time.Location)(specifiedLocation))
+	}
+
+	tl := lord.TimeLord{
+		PreviousTime: previousTime,
+		Location:     specifiedLocation,
+		Start:        request.Source.Start,
+		Stop:         request.Source.Stop,
+		Interval:     request.Source.Interval,
+		Days:         request.Source.Days,
+	}
+
+	versions := []models.Version{}
+
+	if !previousTime.IsZero() {
+		versions = append(versions, models.Version{Time: previousTime})
+	}
+
+	if tl.Check(currentTime) {
+		versions = append(versions, models.Version{Time: currentTime})
+	}
+
+	return versions, nil
+}