*/terraform-examples: add terraform-examples in contrib

CONTRIBUTING.md

@@ -39,7 +39,7 @@ Due to their public nature, GitHub and mailing lists are not appropriate places
 - Go get a couple of projects nesessary for updating docs and examples:
     ```shell
     $ go get github.com/segmentio/terraform-docs
-    $ go get github.com/s-urbaniak/terraform-examples
+    $ go get github.com/coreos/tectonic-installer/contrib/terraform-examples
     ```
 
 ### Contribution Flow
@@ -104,4 +104,4 @@ git tools.
 [modify-installer]: Documentation/contrib/modify-installer.md
 [tf-doc]: https://www.terraform.io/docs/index.html
 [coreos-golang]: https://github.com/coreos/docs/tree/master/golang
-[disclosure]: https://coreos.com/security/disclosure/
+[disclosure]: https://coreos.com/security/disclosure/

Makefile

@@ -53,7 +53,7 @@ destroy: terraform-init
 	cd $(BUILD_DIR) && $(TF_CMD) destroy $(TF_DESTROY_OPTIONS) -force $(TOP_DIR)/platforms/$(PLATFORM)
 
 define terraform-docs
-	$(if $(TF_DOCS),,$(error "terraform-docs revision >= a8b59f8 is required (https://github.com/segmentio/terraform-docs)"))
+	$(if $(TF_DOCS),,$(error terraform-docs revision >= a8b59f8 is required (https://github.com/segmentio/terraform-docs)))
 
 	@echo '<!-- DO NOT EDIT. THIS FILE IS GENERATED BY THE MAKEFILE. -->' > $1
 	@echo '# Terraform variables' >> $1
@@ -62,7 +62,7 @@ define terraform-docs
 endef
 
 define terraform-examples
-	$(if $(TF_EXAMPLES),,$(error "terraform-examples revision >= 83d7ad6 is required (https://github.com/s-urbaniak/terraform-examples)"))
+	$(if $(TF_EXAMPLES),,$(error terraform-examples is required. Execute "go get github.com/coreos/tectonic-installer/contrib/terraform-examples" to install it.))
 	terraform-examples $2 $3 $4 $5 > $1
 endef
 

contrib/terraform-examples/Gopkg.toml

@@ -0,0 +1,3 @@
+[[constraint]]
+  branch = "master"
+  name = "github.com/hashicorp/hcl"

contrib/terraform-examples/README.md

@@ -0,0 +1,8 @@
+## terraform-examples
+
+This is a very simple (and most probably incomplete) tool to generate example terraform.tfvars from files or stdin with variable declarations.
+
+Usage:
+```
+$ usage: terraform-example [-|<FILE>...]
+```

contrib/terraform-examples/main.go

@@ -0,0 +1,213 @@
+package main
+
+import (
+	"errors"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"sort"
+	"strings"
+
+	"github.com/hashicorp/hcl"
+	"github.com/hashicorp/hcl/hcl/ast"
+	"github.com/hashicorp/hcl/hcl/token"
+)
+
+type Variable struct {
+	Name        string
+	Description string
+	Default     string
+}
+
+type Index struct {
+	Variables []Variable
+}
+
+type ByName []Variable
+
+func (s ByName) Len() int           { return len(s) }
+func (s ByName) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+func (s ByName) Less(i, j int) bool { return s[i].Name < s[j].Name }
+
+type stateFunc func(n ast.Node, v *Variable) stateFunc
+
+func newIndex(c []byte) (*Index, error) {
+	file, err := hcl.ParseBytes(c)
+	if err != nil {
+		return nil, err
+	}
+
+	v := &Variable{}
+	idx := &Index{}
+	state := idx.content
+
+	ast.Walk(file.Node, func(n ast.Node) (ast.Node, bool) {
+		state = state(n, v)
+		return n, true
+	})
+
+	idx.Variables = append(idx.Variables, *v)
+	idx.Variables = idx.Variables[1:]
+
+	return idx, nil
+}
+
+func (i *Index) content(n ast.Node, v *Variable) stateFunc {
+	key, ok := n.(*ast.ObjectKey)
+	if !ok {
+		return i.content
+	}
+
+	if key.Token.Type != token.IDENT {
+		return i.content
+	}
+
+	switch key.Token.Text {
+	case "default":
+		return i.defaultValue
+	case "description":
+		return i.description
+	case "variable":
+		i.Variables = append(i.Variables, *v)
+		*v = Variable{}
+		return i.variableName
+	}
+
+	return i.content
+}
+
+func (i *Index) variableName(n ast.Node, v *Variable) stateFunc {
+	key, ok := n.(*ast.ObjectKey)
+	if !ok {
+		return i.variableName
+	}
+
+	if key.Token.Type != token.STRING {
+		return i.variableName
+	}
+
+	v.Name = key.Token.Text
+
+	return i.content
+}
+
+func (i *Index) defaultValue(n ast.Node, v *Variable) stateFunc {
+	if _, ok := n.(*ast.ListType); ok {
+		return i.content
+	}
+
+	if _, ok := n.(*ast.ObjectType); ok {
+		return i.content
+	}
+
+	key, ok := n.(*ast.LiteralType)
+	if !ok {
+		return i.defaultValue
+	}
+
+	switch key.Token.Type {
+	case token.BOOL:
+		v.Default = key.Token.Text
+		return i.content
+	case token.STRING:
+		v.Default = key.Token.Text
+		return i.content
+	}
+
+	return i.defaultValue
+}
+
+func (i *Index) description(n ast.Node, v *Variable) stateFunc {
+	key, ok := n.(*ast.LiteralType)
+	if !ok {
+		return i.description
+	}
+
+	switch key.Token.Type {
+	case token.HEREDOC:
+		v.Description = key.Token.Value().(string)
+		return i.content
+	case token.STRING:
+		v.Description = key.Token.Value().(string)
+		return i.content
+	}
+
+	return i.description
+}
+
+func contents(args []string) ([]byte, error) {
+	if args[0] == "-" {
+		if len(args) > 1 {
+			return nil, errors.New("invalid stdin qualifier: multiple files provided")
+		}
+
+		return ioutil.ReadAll(os.Stdin)
+	}
+
+	var contents []byte
+
+	for _, path := range flag.Args() {
+		c, err := ioutil.ReadFile(path)
+		if err != nil {
+			return nil, err
+		}
+
+		contents = append(contents, c...)
+		contents = append(contents, []byte("\n")...)
+	}
+
+	return contents, nil
+}
+
+func main() {
+	flag.Usage = func() {
+		fmt.Fprintf(os.Stderr, "usage: terraform-example [-|<FILE>...]\n")
+		flag.PrintDefaults()
+	}
+	flag.Parse()
+
+	if len(flag.Args()) == 0 {
+		flag.Usage()
+		os.Exit(1)
+	}
+
+	var c []byte
+	c, err := contents(flag.Args())
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+
+	idx, err := newIndex(c)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+
+	sort.Sort(ByName(idx.Variables))
+
+	for _, v := range idx.Variables {
+		if strings.HasPrefix(v.Description, "(internal)") {
+			continue
+		}
+
+		fmt.Printf("\n")
+
+		v.Name = strings.Trim(v.Name, `"`)
+
+		if strings.HasPrefix(v.Description, "(optional)") {
+			v.Name = `// ` + v.Name
+		}
+
+		for _, l := range strings.Split(strings.TrimSpace(v.Description), "\n") {
+			fmt.Printf("// %s\n", l)
+		}
+
+		if v.Default == "" {
+			fmt.Printf("%s = \"\"\n", v.Name)
+		} else {
+			fmt.Printf("%s = %s\n", v.Name, v.Default)
+		}
+	}
+}

images/tectonic-builder/Dockerfile

@@ -24,7 +24,7 @@ RUN go get github.com/jstemmer/go-junit-report
 
 ### Tools used by 'make structure-check'
 RUN go get github.com/segmentio/terraform-docs
-RUN go get github.com/s-urbaniak/terraform-examples
+RUN go get github.com/coreos/tectonic-installer/contrib/terraform-examples
 RUN go get github.com/bronze1man/yaml2json
 
 ### License parser