print change summary as json (#22)

* print change summary as json

* update test

main.go

@@ -19,6 +19,7 @@ func main() {
 	tree := flag.Bool("tree", false, "[Optional] print changes in tree format")
 	json := flag.Bool("json", false, "[Optional] print changes in json format")
 	html := flag.Bool("html", false, "[Optional] print changes in html format")
+	jsonSum := flag.Bool("json-sum", false, "[Optional] print summary in json format")
 	separateTree := flag.Bool("separate-tree", false, "[Optional] print changes in tree format for add/delete/change/recreate changes")
 	drawable := flag.Bool("draw", false, "[Optional, used only with -tree or -separate-tree] draw trees instead of plain tree")
 	md := flag.Bool("md", false, "[Optional, used only with table view] output table as markdown")
@@ -36,7 +37,7 @@ func main() {
 	}
 
 	args := flag.Args()
-	err := validateFlags(*tree, *separateTree, *drawable, *md, *json, *html, args)
+	err := validateFlags(*tree, *separateTree, *drawable, *md, *json, *jsonSum, *html, args)
 	logIfErrorAndExit("invalid input flags: %s\n", err, flag.Usage)
 
 	newReader, err := reader.CreateReader(args)
@@ -53,7 +54,7 @@ func main() {
 
 	terraformstate.FilterNoOpResources(&terraformState)
 
-	newWriter := writer.CreateWriter(*tree, *separateTree, *drawable, *md, *json, *html, terraformState)
+	newWriter := writer.CreateWriter(*tree, *separateTree, *drawable, *md, *json, *html, *jsonSum, terraformState)
 
 	var outputFile io.Writer = os.Stdout
 
@@ -84,7 +85,7 @@ func logIfErrorAndExit(format string, err error, callback func()) {
 	}
 }
 
-func validateFlags(tree, separateTree, drawable bool, md bool, json bool, html bool, args []string) error {
+func validateFlags(tree, separateTree, drawable bool, md bool, json bool, jsonSum bool, html bool, args []string) error {
 	if tree && md {
 		return fmt.Errorf("both -tree and -md should not be provided")
 	}
@@ -97,8 +98,8 @@ func validateFlags(tree, separateTree, drawable bool, md bool, json bool, html b
 	if !tree && !separateTree && drawable {
 		return fmt.Errorf("drawable should be provided with -tree or -seperate-tree")
 	}
-	if multipleTrueVals(md, json, html) {
-		return fmt.Errorf("only one of -md, -json, or -html should be provided")
+	if multipleTrueVals(md, json, html, jsonSum) {
+		return fmt.Errorf("only one of -md, -json, -json-sum, or -html should be provided")
 	}
 	if len(args) > 1 {
 		return fmt.Errorf("only one argument is allowed which is filename, but got %v", args)

testdata/multiple_format_flags_error.txt

@@ -1,4 +1,4 @@
-invalid input flags: only one of -md, -json, or -html should be provided
+invalid input flags: only one of -md, -json, -json-sum, or -html should be provided
 
 Usage of ./tf-summarize-test [args] [tf-plan.json|tfplan]
 
@@ -8,6 +8,8 @@ Usage of ./tf-summarize-test [args] [tf-plan.json|tfplan]
     	[Optional] print changes in html format
   -json
     	[Optional] print changes in json format
+  -json-sum
+    	[Optional] print summary in json format
   -md
     	[Optional, used only with table view] output table as markdown
   -out string

writer/json-sum.go

@@ -0,0 +1,26 @@
+package writer
+
+import (
+	"fmt"
+	"io"
+
+	"github.com/dineshba/tf-summarize/terraformstate"
+)
+
+type JsonSumWriter struct {
+	changes map[string]terraformstate.ResourceChanges
+}
+
+func (t JsonSumWriter) Write(writer io.Writer) error {
+	result := make(map[string]int, len(t.changes))
+	for k, v := range t.changes {
+		result[k] = len(v)
+	}
+	s, _ := Marshal(map[string]map[string]int{"changes": result})
+	_, err := fmt.Fprint(writer, string(s))
+	return err
+}
+
+func NewJsonSumWriter(changes map[string]terraformstate.ResourceChanges) Writer {
+	return JsonSumWriter{changes: changes}
+}

writer/writer.go

@@ -11,7 +11,7 @@ type Writer interface {
 	Write(writer io.Writer) error
 }
 
-func CreateWriter(tree, separateTree, drawable, mdEnabled, json, html bool, plan tfjson.Plan) Writer {
+func CreateWriter(tree, separateTree, drawable, mdEnabled, json, html bool, jsonSum bool, plan tfjson.Plan) Writer {
 	if tree {
 		return NewTreeWriter(plan.ResourceChanges, drawable)
 	}
@@ -24,6 +24,9 @@ func CreateWriter(tree, separateTree, drawable, mdEnabled, json, html bool, plan
 	if html {
 		return NewHTMLWriter(terraformstate.GetAllResourceChanges(plan), terraformstate.GetAllOutputChanges(plan))
 	}
+	if jsonSum {
+		return NewJsonSumWriter(terraformstate.GetAllResourceChanges(plan))
+	}
 
 	return NewTableWriter(terraformstate.GetAllResourceChanges(plan), terraformstate.GetAllOutputChanges(plan), mdEnabled)
 }