refactor: use helper go functions to handle extracting files from a repository

This standardizes the extraction code and makes it easier to reuse in future implementations of file extraction.

Additionally, this adds a way to extract folders from codebases.

plugins/app-json/triggers.go

@@ -4,8 +4,6 @@ import (
 	"errors"
 	"fmt"
 	"os"
-	"path"
-	"path/filepath"
 	"strings"
 
 	"github.com/dokku/dokku/plugins/common"
@@ -59,95 +57,39 @@ func TriggerAppJSONGetContent(appName string) error {
 	return nil
 }
 
-// TriggerCorePostDeploy sets a property to
-// allow the app to be restored on boot
+// TriggerCorePostDeploy moves the extracted app.json to the app data directory
+// allowing the app to be restored on boot
 func TriggerCorePostDeploy(appName string) error {
-	existingAppJSON := getAppJSONPath(appName)
-	processSpecificAppJSON := fmt.Sprintf("%s.%s", existingAppJSON, os.Getenv("DOKKU_PID"))
-	if common.FileExists(processSpecificAppJSON) {
-		if err := os.Rename(processSpecificAppJSON, existingAppJSON); err != nil {
-			return err
-		}
-	} else if common.FileExists(fmt.Sprintf("%s.missing", processSpecificAppJSON)) {
-		if err := os.Remove(fmt.Sprintf("%s.missing", processSpecificAppJSON)); err != nil {
-			return err
-		}
-
-		if common.FileExists(existingAppJSON) {
-			if err := os.Remove(existingAppJSON); err != nil {
-				return err
-			}
-		}
-	}
-
-	return nil
+	return common.CorePostDeploy(common.CorePostDeployInput{
+		AppName:     appName,
+		Destination: common.GetAppDataDirectory("app-json", appName),
+		PluginName:  "app-json",
+		ExtractedPaths: []common.CorePostDeployPath{
+			{Path: "app.json", IsDirectory: false},
+		},
+	})
 }
 
 // TriggerCorePostExtract ensures that the main app.json is the one specified by app-json-path
 func TriggerCorePostExtract(appName string, sourceWorkDir string) error {
+	destination := common.GetAppDataDirectory("app-json", appName)
 	appJSONPath := strings.Trim(reportComputedAppjsonpath(appName), "/")
 	if appJSONPath == "" {
 		appJSONPath = "app.json"
 	}
 
-	existingAppJSON := getAppJSONPath(appName)
-	files, err := filepath.Glob(fmt.Sprintf("%s.*", existingAppJSON))
-	if err != nil {
-		return err
-	}
-	for _, f := range files {
-		if err := os.Remove(f); err != nil {
-			return err
-		}
-	}
-
-	processSpecificAppJSON := fmt.Sprintf("%s.%s", existingAppJSON, os.Getenv("DOKKU_PID"))
-	results, _ := common.CallPlugnTrigger(common.PlugnTriggerInput{
-		Trigger: "git-get-property",
-		Args:    []string{appName, "source-image"},
-	})
-	appSourceImage := results.StdoutContents()
-
-	results, _ = common.CallPlugnTrigger(common.PlugnTriggerInput{
-		Trigger: "builder-get-property",
-		Args:    []string{appName, "build-dir"},
-	})
-	buildDir := results.StdoutContents()
-
-	repoDefaultAppJSONPath := path.Join(sourceWorkDir, "app.json")
-	if appSourceImage == "" {
-		repoAppJSONPath := path.Join(sourceWorkDir, buildDir, appJSONPath)
-		if !common.FileExists(repoAppJSONPath) {
-			if appJSONPath != "app.json" && common.FileExists(repoDefaultAppJSONPath) {
-				if err := os.Remove(repoDefaultAppJSONPath); err != nil {
-					return err
-				}
-			}
-			return common.TouchFile(fmt.Sprintf("%s.missing", processSpecificAppJSON))
+	validator := func(appName string, path string) error {
+		if !common.FileExists(path) {
+			return nil
 		}
 
-		if err := common.Copy(repoAppJSONPath, processSpecificAppJSON); err != nil {
-			return fmt.Errorf("Unable to extract app.json: %v", err.Error())
-		}
-
-		if appJSONPath != "app.json" {
-			if err := common.Copy(repoAppJSONPath, repoDefaultAppJSONPath); err != nil {
-				return fmt.Errorf("Unable to move app.json into place: %v", err.Error())
-			}
-		}
-	} else {
-		if err := common.CopyFromImage(appName, appSourceImage, path.Join(buildDir, appJSONPath), processSpecificAppJSON); err != nil {
-			return common.TouchFile(fmt.Sprintf("%s.missing", processSpecificAppJSON))
-		}
-	}
-
-	if common.FileExists(processSpecificAppJSON) {
 		result, err := common.CallPlugnTrigger(common.PlugnTriggerInput{
 			Trigger:      "app-json-is-valid",
-			Args:         []string{appName, processSpecificAppJSON},
+			Args:         []string{appName, path},
 			StreamStdout: true,
 			StreamStderr: true,
 		})
+
 		if err != nil {
 			if result.StderrContents() != "" {
 				return errors.New(result.StderrContents())
@@ -155,10 +97,30 @@ func TriggerCorePostExtract(appName string, sourceWorkDir string) error {
 
 			return err
 		}
+		return nil
 	}
 
-	// TODO: add validation to app.json file by ensuring it can be deserialized
-	return nil
+	results, _ := common.CallPlugnTrigger(common.PlugnTriggerInput{
+		Trigger: "builder-get-property",
+		Args:    []string{appName, "build-dir"},
+	})
+	buildDir := results.StdoutContents()
+	return common.CorePostExtract(common.CorePostExtractInput{
+		AppName:       appName,
+		BuildDir:      buildDir,
+		Destination:   destination,
+		PluginName:    "app-json",
+		SourceWorkDir: sourceWorkDir,
+		ToExtract: []common.CorePostExtractToExtract{
+			{
+				Path:        appJSONPath,
+				IsDirectory: false,
+				Name:        "app.json",
+				Destination: "app.json",
+				Validator:   validator,
+			},
+		},
+	})
 }
 
 // TriggerInstall initializes app-json directory structures