config/module: detectors, some more work on Tree

config/module/detect.go

@@ -0,0 +1,50 @@
+package module
+
+import (
+	"fmt"
+	"net/url"
+)
+
+// Detector defines the interface that an invalid URL or a URL with a blank
+// scheme is passed through in order to determine if its shorthand for
+// something else well-known.
+type Detector interface {
+	// Detect will detect whether the string matches a known pattern to
+	// turn it into a proper URL.
+	Detect(string, string) (string, bool, error)
+}
+
+// Detectors is the list of detectors that are tried on an invalid URL.
+// This is also the order they're tried (index 0 is first).
+var Detectors []Detector
+
+func init() {
+	Detectors = []Detector{
+		new(FileDetector),
+	}
+}
+
+// Detect turns a source string into another source string if it is
+// detected to be of a known pattern.
+//
+// This is safe to be called with an already valid source string: Detect
+// will just return it.
+func Detect(src string, pwd string) (string, error) {
+	u, err := url.Parse(src)
+	if err == nil && u.Scheme != "" {
+		// Valid URL
+		return src, nil
+	}
+
+	for _, d := range Detectors {
+		result, ok, err := d.Detect(src, pwd)
+		if err != nil {
+			return "", err
+		}
+		if ok {
+			return result, nil
+		}
+	}
+
+	return "", fmt.Errorf("invalid source string: %s", src)
+}

config/module/detect_file.go

@@ -0,0 +1,28 @@
+package module
+
+import (
+	"fmt"
+	"path/filepath"
+)
+
+// FileDetector implements Detector to detect file paths.
+type FileDetector struct{}
+
+func (d *FileDetector) Detect(src, pwd string) (string, bool, error) {
+	if len(src) == 0 {
+		return "", false, nil
+	}
+
+	// Make sure we're using "/" even on Windows. URLs are "/"-based.
+	src = filepath.ToSlash(src)
+	if !filepath.IsAbs(src) {
+		src = filepath.Join(pwd, src)
+	}
+
+	// Make sure that we don't start with "/" since we add that below
+	if src[0] == '/' {
+		src = src[1:]
+	}
+
+	return fmt.Sprintf("file:///%s", src), true, nil
+}

config/module/detect_file_test.go

@@ -0,0 +1,32 @@
+package module
+
+import (
+	"testing"
+)
+
+func TestFileDetector(t *testing.T) {
+	cases := []struct {
+		Input  string
+		Output string
+	}{
+		{"./foo", "file:///pwd/foo"},
+		{"foo", "file:///pwd/foo"},
+		{"/foo", "file:///foo"},
+	}
+
+	pwd := "/pwd"
+	f := new(FileDetector)
+	for i, tc := range cases {
+		output, ok, err := f.Detect(tc.Input, pwd)
+		if err != nil {
+			t.Fatalf("err: %s", err)
+		}
+		if !ok {
+			t.Fatal("not ok")
+		}
+
+		if output != tc.Output {
+			t.Fatalf("%d: bad: %#v", i, output)
+		}
+	}
+}

config/module/module.go

@@ -4,4 +4,5 @@ package module
 type Module struct {
 	Name   string
 	Source string
+	Dir    string
 }

config/module/module_test.go

@@ -45,3 +45,7 @@ func testModule(n string) string {
 	url.Path = p
 	return url.String()
 }
+
+func testStorage(t *testing.T) Storage {
+	return &FolderStorage{StorageDir: tempDir(t)}
+}

config/module/tree.go

@@ -1,6 +1,9 @@
 package module
 
 import (
+	"fmt"
+	"sync"
+
 	"github.com/hashicorp/terraform/config"
 )
 
@@ -10,8 +13,9 @@ import (
 // all the modules without getting, flatten the tree into something
 // Terraform can use, etc.
 type Tree struct {
-	Config   *config.Config
-	Children []*Tree
+	config   *config.Config
+	children []*Tree
+	lock     sync.Mutex
 }
 
 // GetMode is an enum that describes how modules are loaded.
@@ -35,7 +39,15 @@ const (
 
 // NewTree returns a new Tree for the given config structure.
 func NewTree(c *config.Config) *Tree {
-	return &Tree{Config: c}
+	return &Tree{config: c}
+}
+
+// Children returns the children of this tree (the modules that are
+// imported by this root).
+//
+// This will only return a non-nil value after Load is called.
+func (t *Tree) Children() []*Tree {
+	return nil
 }
 
 // Flatten takes the entire module tree and flattens it into a single
@@ -54,10 +66,10 @@ func (t *Tree) Flatten() (*config.Config, error) {
 // This is only the imports of _this_ level of the tree. To retrieve the
 // full nested imports, you'll have to traverse the tree.
 func (t *Tree) Modules() []*Module {
-	result := make([]*Module, len(t.Config.Modules))
-	for i, m := range t.Config.Modules {
+	result := make([]*Module, len(t.config.Modules))
+	for i, m := range t.config.Modules {
 		result[i] = &Module{
-			Name:   m.Name,
+			Name:      m.Name,
 			Source: m.Source,
 		}
 	}
@@ -70,11 +82,66 @@ func (t *Tree) Modules() []*Module {
 // The parameters are used to tell the tree where to find modules and
 // whether it can download/update modules along the way.
 //
+// Calling this multiple times will reload the tree.
+//
 // Various semantic-like checks are made along the way of loading since
 // module trees inherently require the configuration to be in a reasonably
 // sane state: no circular dependencies, proper module sources, etc. A full
 // suite of validations can be done by running Validate (after loading).
 func (t *Tree) Load(s Storage, mode GetMode) error {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	// Reset the children if we have any
+	t.children = nil
+
+	modules := t.Modules()
+	children := make([]*Tree, len(modules))
+
+	// Go through all the modules and get the directory for them.
+	update := mode == GetModeUpdate
+	for i, m := range modules {
+		source, err := Detect(m.Source, m.Dir)
+		if err != nil {
+			return fmt.Errorf("module %s: %s", m.Name, err)
+		}
+
+		if mode > GetModeNone {
+			// Get the module since we specified we should
+			if err := s.Get(source, update); err != nil {
+				return err
+			}
+		}
+
+		// Get the directory where this module is so we can load it
+		dir, ok, err := s.Dir(source)
+		if err != nil {
+			return err
+		}
+		if !ok {
+			return fmt.Errorf(
+				"module %s: not found, may need to be downloaded", m.Name)
+		}
+
+		// Load the configuration
+		c, err := config.LoadDir(dir)
+		if err != nil {
+			return fmt.Errorf(
+				"module %s: %s", m.Name, err)
+		}
+		children[i] = NewTree(c)
+	}
+
+	// Go through all the children and load them.
+	for _, c := range children {
+		if err := c.Load(s, mode); err != nil {
+			return err
+		}
+	}
+
+	// Set our tree up
+	t.children = children
+
 	return nil
 }
 

config/module/tree_test.go

@@ -5,7 +5,14 @@ import (
 	"testing"
 )
 
-func TestTree(t *testing.T) {
+func TestTree_Load(t *testing.T) {
+	tree := NewTree(testConfig(t, "basic"))
+	if err := tree.Load(testStorage(t), GetModeGet); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+}
+
+func TestTree_Modules(t *testing.T) {
 	tree := NewTree(testConfig(t, "basic"))
 	actual := tree.Modules()