support -html flag to render output as HTML

This addresses issue #69 to support HTML output.

This also...

- updates the README usage docs
- validates that multiple, conflicting format flags are not provided
- fixes a bug in the tests to properly validate expected tf-summarize errors

Signed-off-by: Mike Ball <mikedball@gmail.com>

README.md

@@ -110,10 +110,16 @@ Usage of tf-summarize [args] [tf-plan.json|tfplan]
 
  -draw
  [Optional, used only with -tree or -separate-tree] draw trees instead of plain tree
+ -html
+ [Optional] print changes in html format
+ -json
+ [Optional] print changes in json format
+ -md
+ [Optional, used only with table view] output table as markdown
  -out string
  [Optional] write output to file
  -separate-tree
- [Optional] print changes in tree format for each add/delete/change/recreate changes
+ [Optional] print changes in tree format for add/delete/change/recreate changes
  -tree
  [Optional] print changes in tree format
  -v print version

main.go

@@ -18,6 +18,7 @@ func main() {
  printVersion := flag.Bool("v", false, "print version")
  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")
  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")
@@ -35,7 +36,7 @@ func main() {
  }
 
  args := flag.Args()
- err := validateFlags(*tree, *separateTree, *drawable, *md, args)
+ err := validateFlags(*tree, *separateTree, *drawable, *md, *json, *html, args)
  logIfErrorAndExit("invalid input flags: %s\n", err, flag.Usage)
 
  newReader, err := reader.CreateReader(args)
@@ -52,7 +53,7 @@ func main() {
 
  terraformstate.FilterNoOpResources(&terraformState)
 
- newWriter := writer.CreateWriter(*tree, *separateTree, *drawable, *md, *json, terraformState)
+ newWriter := writer.CreateWriter(*tree, *separateTree, *drawable, *md, *json, *html, terraformState)
 
  var outputFile io.Writer = os.Stdout
 
@@ -83,7 +84,7 @@ func logIfErrorAndExit(format string, err error, callback func()) {
  }
 }
 
-func validateFlags(tree, separateTree, drawable bool, md bool, args []string) error {
+func validateFlags(tree, separateTree, drawable bool, md bool, json bool, html bool, args []string) error {
  if tree && md {
  return fmt.Errorf("both -tree and -md should not be provided")
  }
@@ -96,8 +97,23 @@ func validateFlags(tree, separateTree, drawable bool, md bool, args []string) er
  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 len(args) > 1 {
  return fmt.Errorf("only one argument is allowed which is filename, but got %v", args)
  }
  return nil
 }
+
+func multipleTrueVals(vals ...bool) bool {
+ v := []bool{}
+
+ for _, val := range vals {
+ if val {
+ v = append(v, val)
+ }
+ }
+
+ return len(v) > 1
+}

main_test.go

@@ -61,13 +61,20 @@ func TestTFSummarize(t *testing.T) {
  }, {
  command: fmt.Sprintf("cat example/tfplan.json | ./%s -md", testExecutable),
  expectedOutput: "basic.txt",
+ }, {
+ command: fmt.Sprintf("cat example/tfplan.json | ./%s -html", testExecutable),
+ expectedOutput: "basic.html",
+ }, {
+ command: fmt.Sprintf("cat example/tfplan.json | ./%s -md -html", testExecutable),
+ expectedError: fmt.Errorf("exit status 1"),
+ expectedOutput: "multiple_format_flags_error.txt",
  }}
 
  for _, test := range tests {
  t.Run(fmt.Sprintf("when tf-summarize is passed '%q'", test.command), func(t *testing.T) {
- output, err := exec.Command("/bin/sh", "-c", test.command).CombinedOutput()
- if err != nil && test.expectedError == nil {
- t.Errorf("expected '%s' not to error; got '%v'", test.command, err)
+ output, cmdErr := exec.Command("/bin/sh", "-c", test.command).CombinedOutput()
+ if cmdErr != nil && test.expectedError == nil {
+ t.Errorf("expected '%s' not to error; got '%v'", test.command, cmdErr)
  }
 
  b, err := os.ReadFile(fmt.Sprintf("testdata/%s", test.expectedOutput))
@@ -77,12 +84,12 @@ func TestTFSummarize(t *testing.T) {
 
  expected := string(b)
 
- if test.expectedError != nil && err == nil {
- t.Errorf("expected error '%s'; got '%v'", test.expectedError.Error(), err)
+ if test.expectedError != nil && cmdErr == nil {
+ t.Errorf("expected error '%s'; got '%v'", test.expectedError.Error(), cmdErr)
  }
 
- if test.expectedError != nil && err != nil && test.expectedError.Error() != err.Error() {
- t.Errorf("expected error '%s'; got '%v'", test.expectedError.Error(), err.Error())
+ if test.expectedError != nil && cmdErr != nil && test.expectedError.Error() != cmdErr.Error() {
+ t.Errorf("expected error '%s'; got '%v'", test.expectedError.Error(), cmdErr.Error())
  }
 
  if string(output) != expected {

testdata/basic.html

@@ -0,0 +1,20 @@
+<table>
+ <tr>
+ <th>CHANGE</th>
+ <th>RESOURCE</th>
+ </tr>
+ <tr>
+ <td>add</td>
+ <td>
+ <ul>
+ <li>github_repository.terraform_plan_summary</li>
+ <li>module.github["demo-repository"].github_branch.development</li>
+ <li>module.github["demo-repository"].github_branch.main</li>
+ <li>module.github["demo-repository"].github_repository.repository</li>
+ <li>module.github["terraform-plan-summary"].github_branch.development</li>
+ <li>module.github["terraform-plan-summary"].github_branch.main</li>
+ <li>module.github["terraform-plan-summary"].github_repository.repository</li>
+ </ul>
+ </td>
+ </tr>
+</table>

testdata/multiple_format_flags_error.txt

@@ -0,0 +1,19 @@
+invalid input flags: only one of -md, -json, or -html should be provided
+
+Usage of ./tf-summarize-test [args] [tf-plan.json|tfplan]
+
+ -draw
+ [Optional, used only with -tree or -separate-tree] draw trees instead of plain tree
+ -html
+ [Optional] print changes in html format
+ -json
+ [Optional] print changes in json format
+ -md
+ [Optional, used only with table view] output table as markdown
+ -out string
+ [Optional] write output to file
+ -separate-tree
+ [Optional] print changes in tree format for add/delete/change/recreate changes
+ -tree
+ [Optional] print changes in tree format
+ -v print version

writer/html.go

@@ -0,0 +1,50 @@
+package writer
+
+import (
+ "io"
+ "path"
+ "text/template"
+
+ "github.com/dineshba/tf-summarize/terraformstate"
+)
+
+// HTMLWriter is a Writer that writes HTML.
+type HTMLWriter struct {
+ ResourceChanges map[string]terraformstate.ResourceChanges
+ OutputChanges map[string][]string
+}
+
+// Write outputs the HTML summary to the io.Writer it's passed.
+func (t HTMLWriter) Write(writer io.Writer) error {
+ templatesDir := "templates"
+ rcTmpl := "resourceChanges.html"
+ tmpl, err := template.New(rcTmpl).ParseFS(templates, path.Join(templatesDir, rcTmpl))
+ if err != nil {
+ return err
+ }
+
+ err = tmpl.Execute(writer, t)
+ if err != nil {
+ return err
+ }
+
+ if !hasOutputChanges(t.OutputChanges) {
+ return nil
+ }
+
+ ocTmpl := "outputChanges.html"
+ outputTmpl, err := template.New(ocTmpl).ParseFS(templates, path.Join(templatesDir, ocTmpl))
+ if err != nil {
+ return err
+ }
+
+ return outputTmpl.Execute(writer, t)
+}
+
+// NewHTMLWriter returns a new HTMLWriter with the configuration it's passed.
+func NewHTMLWriter(changes map[string]terraformstate.ResourceChanges, outputChanges map[string][]string) Writer {
+ return HTMLWriter{
+ ResourceChanges: changes,
+ OutputChanges: outputChanges,
+ }
+}

writer/table.go

@@ -44,7 +44,7 @@ func (t TableWriter) Write(writer io.Writer) error {
  table.Render()
 
  // Disable the Output Summary if there are no outputs to display
- if len(t.outputChanges["add"]) > 0 || len(t.outputChanges["delete"]) > 0 || len(t.outputChanges["update"]) > 0 {
+ if hasOutputChanges(t.outputChanges) {
  tableString = make([][]string, 0, 4)
  for _, change := range tableOrder {
  changedOutputs := t.outputChanges[change]

writer/templates/outputChanges.html

@@ -0,0 +1,14 @@
+<table>
+ <tr>
+ <th>CHANGE</th>
+ <th>OUTPUT</th>
+ </tr>{{ range $change, $resources := .OutputChanges }}{{ $length := len $resources }}{{ if gt $length 0 }}
+ <tr>
+ <td>{{ $change }}</td>
+ <td>
+ <ul>{{ range $i, $r := $resources }}
+ <li>{{ $r.Address }}</li>{{ end }}
+ </ul>
+ </td>
+ </tr>{{ end }}{{ end }}
+</table>

writer/templates/resourceChanges.html

@@ -0,0 +1,14 @@
+<table>
+ <tr>
+ <th>CHANGE</th>
+ <th>RESOURCE</th>
+ </tr>{{ range $change, $resources := .ResourceChanges }}{{ $length := len $resources }}{{ if gt $length 0 }}
+ <tr>
+ <td>{{ $change }}</td>
+ <td>
+ <ul>{{ range $i, $r := $resources }}
+ <li>{{ $r.Address }}</li>{{ end }}
+ </ul>
+ </td>
+ </tr>{{ end }}{{ end }}
+</table>

writer/util.go

@@ -0,0 +1,21 @@
+package writer
+
+import "embed"
+
+// Embed the templates directory in the compiled binary.
+//
+//go:embed templates
+var templates embed.FS
+
+func hasOutputChanges(opChanges map[string][]string) bool {
+ hasChanges := false
+
+ for _, v := range opChanges {
+ if len(v) > 0 {
+ hasChanges = true
+ break
+ }
+ }
+
+ return hasChanges
+}

writer/writer.go

@@ -11,8 +11,7 @@ type Writer interface {
  Write(writer io.Writer) error
 }
 
-func CreateWriter(tree, separateTree, drawable, mdEnabled, json bool, plan tfjson.Plan) Writer {
-
+func CreateWriter(tree, separateTree, drawable, mdEnabled, json, html bool, plan tfjson.Plan) Writer {
  if tree {
  return NewTreeWriter(plan.ResourceChanges, drawable)
  }
@@ -22,6 +21,9 @@ func CreateWriter(tree, separateTree, drawable, mdEnabled, json bool, plan tfjso
  if json {
  return NewJSONWriter(plan.ResourceChanges)
  }
+ if html {
+ return NewHTMLWriter(terraformstate.GetAllResourceChanges(plan), terraformstate.GetAllOutputChanges(plan))
+ }
 
  return NewTableWriter(terraformstate.GetAllResourceChanges(plan), terraformstate.GetAllOutputChanges(plan), mdEnabled)
 }