2 files changed, 328 insertions, 0 deletions
diff --git a/vendor/go4.org/wkfs/gcs/gcs.go b/vendor/go4.org/wkfs/gcs/gcs.go
new file mode 100644
index 0000000..21f2551
--- /dev/null
+++ b/vendor/go4.org/wkfs/gcs/gcs.go
@@ -0,0 +1,196 @@
+/*
+Copyright 2014 The Camlistore Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package gcs registers a Google Cloud Storage filesystem at the
+// well-known /gcs/ filesystem path if the current machine is running
+// on Google Compute Engine.
+//
+// It was initially only meant for small files, and as such, it can only
+// read files smaller than 1MB for now.
+package gcs // import "go4.org/wkfs/gcs"
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path"
+	"strings"
+	"time"
+
+	"go4.org/wkfs"
+	"golang.org/x/net/context"
+	"golang.org/x/oauth2"
+	"golang.org/x/oauth2/google"
+	"google.golang.org/cloud"
+	"google.golang.org/cloud/compute/metadata"
+	"google.golang.org/cloud/storage"
+)
+
+// Max size for all files read, because we use a bytes.Reader as our file
+// reader, instead of storage.NewReader. This is because we get all wkfs.File
+// methods for free by embedding a bytes.Reader. This filesystem was only supposed
+// to be for configuration data only, so this is ok for now.
+const maxSize = 1 << 20
+
+func init() {
+	if !metadata.OnGCE() {
+		return
+	}
+	hc, err := google.DefaultClient(oauth2.NoContext)
+	if err != nil {
+		registerBrokenFS(fmt.Errorf("could not get http client for context: %v", err))
+		return
+	}
+	projID, err := metadata.ProjectID()
+	if projID == "" || err != nil {
+		registerBrokenFS(fmt.Errorf("could not get GCE project ID: %v", err))
+		return
+	}
+	ctx := cloud.NewContext(projID, hc)
+	sc, err := storage.NewClient(ctx)
+	if err != nil {
+		registerBrokenFS(fmt.Errorf("could not get cloud storage client: %v", err))
+		return
+	}
+	wkfs.RegisterFS("/gcs/", &gcsFS{
+		ctx: ctx,
+		sc:  sc,
+	})
+}
+
+type gcsFS struct {
+	ctx context.Context
+	sc  *storage.Client
+	err error // sticky error
+}
+
+func registerBrokenFS(err error) {
+	wkfs.RegisterFS("/gcs/", &gcsFS{
+		err: err,
+	})
+}
+
+func (fs *gcsFS) parseName(name string) (bucket, fileName string, err error) {
+	if fs.err != nil {
+		return "", "", fs.err
+	}
+	name = strings.TrimPrefix(name, "/gcs/")
+	i := strings.Index(name, "/")
+	if i < 0 {
+		return name, "", nil
+	}
+	return name[:i], name[i+1:], nil
+}
+
+// Open opens the named file for reading. It returns an error if the file size
+// is larger than 1 << 20.
+func (fs *gcsFS) Open(name string) (wkfs.File, error) {
+	bucket, fileName, err := fs.parseName(name)
+	if err != nil {
+		return nil, err
+	}
+	obj := fs.sc.Bucket(bucket).Object(fileName)
+	attrs, err := obj.Attrs(fs.ctx)
+	if err != nil {
+		return nil, err
+	}
+	size := attrs.Size
+	if size > maxSize {
+		return nil, fmt.Errorf("file %s too large (%d bytes) for /gcs/ filesystem", name, size)
+	}
+	rc, err := obj.NewReader(fs.ctx)
+	if err != nil {
+		return nil, err
+	}
+	defer rc.Close()
+
+	slurp, err := ioutil.ReadAll(io.LimitReader(rc, size))
+	if err != nil {
+		return nil, err
+	}
+	return &file{
+		name:   name,
+		Reader: bytes.NewReader(slurp),
+	}, nil
+}
+
+func (fs *gcsFS) Stat(name string) (os.FileInfo, error) { return fs.Lstat(name) }
+func (fs *gcsFS) Lstat(name string) (os.FileInfo, error) {
+	bucket, fileName, err := fs.parseName(name)
+	if err != nil {
+		return nil, err
+	}
+	attrs, err := fs.sc.Bucket(bucket).Object(fileName).Attrs(fs.ctx)
+	if err == storage.ErrObjectNotExist {
+		return nil, os.ErrNotExist
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &statInfo{
+		name: attrs.Name,
+		size: attrs.Size,
+	}, nil
+}
+
+func (fs *gcsFS) MkdirAll(path string, perm os.FileMode) error { return nil }
+
+func (fs *gcsFS) OpenFile(name string, flag int, perm os.FileMode) (wkfs.FileWriter, error) {
+	bucket, fileName, err := fs.parseName(name)
+	if err != nil {
+		return nil, err
+	}
+	switch flag {
+	case os.O_WRONLY | os.O_CREATE | os.O_EXCL:
+	case os.O_WRONLY | os.O_CREATE | os.O_TRUNC:
+	default:
+		return nil, fmt.Errorf("Unsupported OpenFlag flag mode %d on Google Cloud Storage", flag)
+	}
+	if flag&os.O_EXCL != 0 {
+		if _, err := fs.Stat(name); err == nil {
+			return nil, os.ErrExist
+		}
+	}
+	// TODO(mpl): consider adding perm to the object's ObjectAttrs.Metadata
+	return fs.sc.Bucket(bucket).Object(fileName).NewWriter(fs.ctx), nil
+}
+
+type statInfo struct {
+	name    string
+	size    int64
+	isDir   bool
+	modtime time.Time
+}
+
+func (si *statInfo) IsDir() bool        { return si.isDir }
+func (si *statInfo) ModTime() time.Time { return si.modtime }
+func (si *statInfo) Mode() os.FileMode  { return 0644 }
+func (si *statInfo) Name() string       { return path.Base(si.name) }
+func (si *statInfo) Size() int64        { return si.size }
+func (si *statInfo) Sys() interface{}   { return nil }
+
+type file struct {
+	name string
+	*bytes.Reader
+}
+
+func (*file) Close() error   { return nil }
+func (f *file) Name() string { return path.Base(f.name) }
+func (f *file) Stat() (os.FileInfo, error) {
+	panic("Stat not implemented on /gcs/ files yet")
+}
diff --git a/vendor/go4.org/wkfs/wkfs.go b/vendor/go4.org/wkfs/wkfs.go
new file mode 100644
index 0000000..f4df062
--- /dev/null
+++ b/vendor/go4.org/wkfs/wkfs.go
@@ -0,0 +1,132 @@
+/*
+Copyright 2014 The Camlistore Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package wkfs implements the pluggable "well-known filesystem" abstraction layer.
+//
+// Instead of accessing files directly through the operating system
+// using os.Open or os.Stat, code should use wkfs.Open or wkfs.Stat,
+// which first try to intercept paths at well-known top-level
+// directories representing previously-registered mount types,
+// otherwise fall through to the operating system paths.
+//
+// Example of top-level well-known directories that might be
+// registered include /gcs/bucket/object for Google Cloud Storage or
+// /s3/bucket/object for AWS S3.
+package wkfs // import "go4.org/wkfs"
+
+import (
+	"io"
+	"io/ioutil"
+	"os"
+	"strings"
+)
+
+type File interface {
+	io.Reader
+	io.ReaderAt
+	io.Closer
+	io.Seeker
+	Name() string
+	Stat() (os.FileInfo, error)
+}
+
+type FileWriter interface {
+	io.Writer
+	io.Closer
+}
+
+func Open(name string) (File, error)               { return fs(name).Open(name) }
+func Stat(name string) (os.FileInfo, error)        { return fs(name).Stat(name) }
+func Lstat(name string) (os.FileInfo, error)       { return fs(name).Lstat(name) }
+func MkdirAll(path string, perm os.FileMode) error { return fs(path).MkdirAll(path, perm) }
+func OpenFile(name string, flag int, perm os.FileMode) (FileWriter, error) {
+	return fs(name).OpenFile(name, flag, perm)
+}
+func Create(name string) (FileWriter, error) {
+	// like os.Create but WRONLY instead of RDWR because we don't
+	// expose a Reader here.
+	return OpenFile(name, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0666)
+}
+
+func fs(name string) FileSystem {
+	for pfx, fs := range wkFS {
+		if strings.HasPrefix(name, pfx) {
+			return fs
+		}
+	}
+	return osFS{}
+}
+
+type osFS struct{}
+
+func (osFS) Open(name string) (File, error)               { return os.Open(name) }
+func (osFS) Stat(name string) (os.FileInfo, error)        { return os.Stat(name) }
+func (osFS) Lstat(name string) (os.FileInfo, error)       { return os.Lstat(name) }
+func (osFS) MkdirAll(path string, perm os.FileMode) error { return os.MkdirAll(path, perm) }
+func (osFS) OpenFile(name string, flag int, perm os.FileMode) (FileWriter, error) {
+	return os.OpenFile(name, flag, perm)
+}
+
+type FileSystem interface {
+	Open(name string) (File, error)
+	OpenFile(name string, flag int, perm os.FileMode) (FileWriter, error)
+	Stat(name string) (os.FileInfo, error)
+	Lstat(name string) (os.FileInfo, error)
+	MkdirAll(path string, perm os.FileMode) error
+}
+
+// well-known filesystems
+var wkFS = map[string]FileSystem{}
+
+// RegisterFS registers a well-known filesystem. It intercepts
+// anything beginning with prefix (which must start and end with a
+// forward slash) and forwards it to fs.
+func RegisterFS(prefix string, fs FileSystem) {
+	if !strings.HasPrefix(prefix, "/") || !strings.HasSuffix(prefix, "/") {
+		panic("bogus prefix: " + prefix)
+	}
+	if _, dup := wkFS[prefix]; dup {
+		panic("duplication registration of " + prefix)
+	}
+	wkFS[prefix] = fs
+}
+
+// WriteFile writes data to a file named by filename.
+// If the file does not exist, WriteFile creates it with permissions perm;
+// otherwise WriteFile truncates it before writing.
+func WriteFile(filename string, data []byte, perm os.FileMode) error {
+	f, err := OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)
+	if err != nil {
+		return err
+	}
+	n, err := f.Write(data)
+	if err == nil && n < len(data) {
+		err = io.ErrShortWrite
+	}
+	if err1 := f.Close(); err == nil {
+		err = err1
+	}
+	return err
+}
+
+func ReadFile(filename string) ([]byte, error) {
+	f, err := Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+	return ioutil.ReadAll(f)
+}