hugo/deploy/deploy.go
2019-09-13 14:53:36 +02:00

645 lines
19 KiB
Go

// Copyright 2019 The Hugo Authors. All rights reserved.
//
// 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 deploy
import (
"bytes"
"compress/gzip"
"context"
"crypto/md5"
"fmt"
"io"
"io/ioutil"
"mime"
"os"
"path/filepath"
"regexp"
"runtime"
"sort"
"strings"
"sync"
"github.com/dustin/go-humanize"
"github.com/gohugoio/hugo/config"
"github.com/pkg/errors"
"github.com/spf13/afero"
jww "github.com/spf13/jwalterweatherman"
"golang.org/x/text/unicode/norm"
"gocloud.dev/blob"
_ "gocloud.dev/blob/fileblob" // import
_ "gocloud.dev/blob/gcsblob" // import
_ "gocloud.dev/blob/s3blob" // import
)
// Deployer supports deploying the site to target cloud providers.
type Deployer struct {
localFs afero.Fs
bucket *blob.Bucket
target *target // the target to deploy to
matchers []*matcher // matchers to apply to uploaded files
ordering []*regexp.Regexp // orders uploads
quiet bool // true reduces STDOUT
confirm bool // true enables confirmation before making changes
dryRun bool // true skips conformations and prints changes instead of applying them
force bool // true forces upload of all files
invalidateCDN bool // true enables invalidate CDN cache (if possible)
maxDeletes int // caps the # of files to delete; -1 to disable
// For tests...
summary deploySummary // summary of latest Deploy results
}
type deploySummary struct {
NumLocal, NumRemote, NumUploads, NumDeletes int
}
// New constructs a new *Deployer.
func New(cfg config.Provider, localFs afero.Fs) (*Deployer, error) {
targetName := cfg.GetString("target")
// Load the [deployment] section of the config.
dcfg, err := decodeConfig(cfg)
if err != nil {
return nil, err
}
if len(dcfg.Targets) == 0 {
return nil, errors.New("no deployment targets found")
}
// Find the target to deploy to.
var tgt *target
if targetName == "" {
// Default to the first target.
tgt = dcfg.Targets[0]
} else {
for _, t := range dcfg.Targets {
if t.Name == targetName {
tgt = t
}
}
if tgt == nil {
return nil, fmt.Errorf("deployment target %q not found", targetName)
}
}
return &Deployer{
localFs: localFs,
target: tgt,
matchers: dcfg.Matchers,
ordering: dcfg.ordering,
quiet: cfg.GetBool("quiet"),
confirm: cfg.GetBool("confirm"),
dryRun: cfg.GetBool("dryRun"),
force: cfg.GetBool("force"),
invalidateCDN: cfg.GetBool("invalidateCDN"),
maxDeletes: cfg.GetInt("maxDeletes"),
}, nil
}
func (d *Deployer) openBucket(ctx context.Context) (*blob.Bucket, error) {
if d.bucket != nil {
return d.bucket, nil
}
jww.FEEDBACK.Printf("Deploying to target %q (%s)\n", d.target.Name, d.target.URL)
return blob.OpenBucket(ctx, d.target.URL)
}
// Deploy deploys the site to a target.
func (d *Deployer) Deploy(ctx context.Context) error {
bucket, err := d.openBucket(ctx)
if err != nil {
return err
}
// Load local files from the source directory.
local, err := walkLocal(d.localFs, d.matchers)
if err != nil {
return err
}
jww.INFO.Printf("Found %d local files.\n", len(local))
d.summary.NumLocal = len(local)
// Load remote files from the target.
remote, err := walkRemote(ctx, bucket)
if err != nil {
return err
}
jww.INFO.Printf("Found %d remote files.\n", len(remote))
d.summary.NumRemote = len(remote)
// Diff local vs remote to see what changes need to be applied.
uploads, deletes := findDiffs(local, remote, d.force)
d.summary.NumUploads = len(uploads)
d.summary.NumDeletes = len(deletes)
if len(uploads)+len(deletes) == 0 {
if !d.quiet {
jww.FEEDBACK.Println("No changes required.")
}
return nil
}
if !d.quiet {
jww.FEEDBACK.Println(summarizeChanges(uploads, deletes))
}
// Ask for confirmation before proceeding.
if d.confirm && !d.dryRun {
fmt.Printf("Continue? (Y/n) ")
var confirm string
if _, err := fmt.Scanln(&confirm); err != nil {
return err
}
if confirm != "" && confirm[0] != 'y' && confirm[0] != 'Y' {
return errors.New("aborted")
}
}
// Order the uploads. They are organized in groups; all uploads in a group
// must be complete before moving on to the next group.
uploadGroups := applyOrdering(d.ordering, uploads)
// Apply the changes in parallel, using an inverted worker
// pool (https://www.youtube.com/watch?v=5zXAHh5tJqQ&t=26m58s).
// sem prevents more than nParallel concurrent goroutines.
const nParallel = 10
var errs []error
var errMu sync.Mutex // protects errs
for _, uploads := range uploadGroups {
// Short-circuit for an empty group.
if len(uploads) == 0 {
continue
}
// Within the group, apply uploads in parallel.
sem := make(chan struct{}, nParallel)
for _, upload := range uploads {
if d.dryRun {
if !d.quiet {
jww.FEEDBACK.Printf("[DRY RUN] Would upload: %v\n", upload)
}
continue
}
sem <- struct{}{}
go func(upload *fileToUpload) {
if err := doSingleUpload(ctx, bucket, upload); err != nil {
errMu.Lock()
defer errMu.Unlock()
errs = append(errs, err)
}
<-sem
}(upload)
}
// Wait for all uploads in the group to finish.
for n := nParallel; n > 0; n-- {
sem <- struct{}{}
}
}
if d.maxDeletes != -1 && len(deletes) > d.maxDeletes {
jww.WARN.Printf("Skipping %d deletes because it is more than --maxDeletes (%d). If this is expected, set --maxDeletes to a larger number, or -1 to disable this check.\n", len(deletes), d.maxDeletes)
d.summary.NumDeletes = 0
} else {
// Apply deletes in parallel.
sort.Slice(deletes, func(i, j int) bool { return deletes[i] < deletes[j] })
sem := make(chan struct{}, nParallel)
for _, del := range deletes {
if d.dryRun {
if !d.quiet {
jww.FEEDBACK.Printf("[DRY RUN] Would delete %s\n", del)
}
continue
}
sem <- struct{}{}
go func(del string) {
jww.INFO.Printf("Deleting %s...\n", del)
if err := bucket.Delete(ctx, del); err != nil {
errMu.Lock()
defer errMu.Unlock()
errs = append(errs, err)
}
<-sem
}(del)
}
// Wait for all deletes to finish.
for n := nParallel; n > 0; n-- {
sem <- struct{}{}
}
}
if len(errs) > 0 {
if !d.quiet {
jww.FEEDBACK.Printf("Encountered %d errors.\n", len(errs))
}
return errs[0]
}
if !d.quiet {
jww.FEEDBACK.Println("Success!")
}
if d.invalidateCDN && d.target.CloudFrontDistributionID != "" {
jww.FEEDBACK.Println("Invalidating CloudFront CDN...")
if err := InvalidateCloudFront(ctx, d.target.CloudFrontDistributionID); err != nil {
jww.FEEDBACK.Printf("Failed to invalidate CloudFront CDN: %v\n", err)
return err
}
jww.FEEDBACK.Println("Success!")
}
return nil
}
// summarizeChanges creates a text description of the proposed changes.
func summarizeChanges(uploads []*fileToUpload, deletes []string) string {
uploadSize := int64(0)
for _, u := range uploads {
uploadSize += u.Local.UploadSize
}
return fmt.Sprintf("Identified %d file(s) to upload, totaling %s, and %d file(s) to delete.", len(uploads), humanize.Bytes(uint64(uploadSize)), len(deletes))
}
// doSingleUpload executes a single file upload.
func doSingleUpload(ctx context.Context, bucket *blob.Bucket, upload *fileToUpload) error {
jww.INFO.Printf("Uploading %v...\n", upload)
opts := &blob.WriterOptions{
CacheControl: upload.Local.CacheControl(),
ContentEncoding: upload.Local.ContentEncoding(),
ContentType: upload.Local.ContentType(),
}
w, err := bucket.NewWriter(ctx, upload.Local.SlashPath, opts)
if err != nil {
return err
}
r, err := upload.Local.Reader()
if err != nil {
return err
}
defer r.Close()
_, err = io.Copy(w, r)
if err != nil {
return err
}
if err := w.Close(); err != nil {
return err
}
return nil
}
// localFile represents a local file from the source. Use newLocalFile to
// construct one.
type localFile struct {
// NativePath is the native path to the file (using file.Separator).
NativePath string
// SlashPath is NativePath converted to use /.
SlashPath string
// UploadSize is the size of the content to be uploaded. It may not
// be the same as the local file size if the content will be
// gzipped before upload.
UploadSize int64
fs afero.Fs
matcher *matcher
md5 []byte // cache
gzipped bytes.Buffer // cached of gzipped contents if gzipping
}
// newLocalFile initializes a *localFile.
func newLocalFile(fs afero.Fs, nativePath, slashpath string, m *matcher) (*localFile, error) {
f, err := fs.Open(nativePath)
if err != nil {
return nil, err
}
defer f.Close()
lf := &localFile{
NativePath: nativePath,
SlashPath: slashpath,
fs: fs,
matcher: m,
}
if m != nil && m.Gzip {
// We're going to gzip the content. Do it once now, and cache the result
// in gzipped. The UploadSize is the size of the gzipped content.
gz := gzip.NewWriter(&lf.gzipped)
if _, err := io.Copy(gz, f); err != nil {
return nil, err
}
if err := gz.Close(); err != nil {
return nil, err
}
lf.UploadSize = int64(lf.gzipped.Len())
} else {
// Raw content. Just get the UploadSize.
info, err := f.Stat()
if err != nil {
return nil, err
}
lf.UploadSize = info.Size()
}
return lf, nil
}
// Reader returns an io.ReadCloser for reading the content to be uploaded.
// The caller must call Close on the returned ReaderCloser.
// The reader content may not be the same as the local file content due to
// gzipping.
func (lf *localFile) Reader() (io.ReadCloser, error) {
if lf.matcher != nil && lf.matcher.Gzip {
// We've got the gzipped contents cached in gzipped.
// Note: we can't use lf.gzipped directly as a Reader, since we it discards
// data after it is read, and we may read it more than once.
return ioutil.NopCloser(bytes.NewReader(lf.gzipped.Bytes())), nil
}
// Not expected to fail since we did it successfully earlier in newLocalFile,
// but could happen due to changes in the underlying filesystem.
return lf.fs.Open(lf.NativePath)
}
// CacheControl returns the Cache-Control header to use for lf, based on the
// first matching matcher (if any).
func (lf *localFile) CacheControl() string {
if lf.matcher == nil {
return ""
}
return lf.matcher.CacheControl
}
// ContentEncoding returns the Content-Encoding header to use for lf, based
// on the matcher's Content-Encoding and Gzip fields.
func (lf *localFile) ContentEncoding() string {
if lf.matcher == nil {
return ""
}
if lf.matcher.Gzip {
return "gzip"
}
return lf.matcher.ContentEncoding
}
// ContentType returns the Content-Type header to use for lf.
// It first checks if there's a Content-Type header configured via a matching
// matcher; if not, it tries to generate one based on the filename extension.
// If this fails, the Content-Type will be the empty string. In this case, Go
// Cloud will automatically try to infer a Content-Type based on the file
// content.
func (lf *localFile) ContentType() string {
if lf.matcher != nil && lf.matcher.ContentType != "" {
return lf.matcher.ContentType
}
// TODO: Hugo has a MediaType and a MediaTypes list and also a concept
// of custom MIME types.
// Use 1) The matcher 2) Hugo's MIME types 3) TypeByExtension.
return mime.TypeByExtension(filepath.Ext(lf.NativePath))
}
// Force returns true if the file should be forced to re-upload based on the
// matching matcher.
func (lf *localFile) Force() bool {
return lf.matcher != nil && lf.matcher.Force
}
// MD5 returns an MD5 hash of the content to be uploaded.
func (lf *localFile) MD5() []byte {
if len(lf.md5) > 0 {
return lf.md5
}
h := md5.New()
r, err := lf.Reader()
if err != nil {
return nil
}
defer r.Close()
if _, err := io.Copy(h, r); err != nil {
return nil
}
lf.md5 = h.Sum(nil)
return lf.md5
}
// walkLocal walks the source directory and returns a flat list of files,
// using localFile.SlashPath as the map keys.
func walkLocal(fs afero.Fs, matchers []*matcher) (map[string]*localFile, error) {
retval := map[string]*localFile{}
err := afero.Walk(fs, "", func(path string, info os.FileInfo, err error) error {
if err != nil {
return err
}
if info.IsDir() {
// Skip hidden directories.
if path != "" && strings.HasPrefix(info.Name(), ".") {
return filepath.SkipDir
}
return nil
}
// .DS_Store is an internal MacOS attribute file; skip it.
if info.Name() == ".DS_Store" {
return nil
}
// When a file system is HFS+, its filepath is in NFD form.
if runtime.GOOS == "darwin" {
path = norm.NFC.String(path)
}
// Find the first matching matcher (if any).
slashpath := filepath.ToSlash(path)
var m *matcher
for _, cur := range matchers {
if cur.Matches(slashpath) {
m = cur
break
}
}
lf, err := newLocalFile(fs, path, slashpath, m)
if err != nil {
return err
}
retval[lf.SlashPath] = lf
return nil
})
if err != nil {
return nil, err
}
return retval, nil
}
// walkRemote walks the target bucket and returns a flat list.
func walkRemote(ctx context.Context, bucket *blob.Bucket) (map[string]*blob.ListObject, error) {
retval := map[string]*blob.ListObject{}
iter := bucket.List(nil)
for {
obj, err := iter.Next(ctx)
if err == io.EOF {
break
}
if err != nil {
return nil, err
}
// If the remote didn't give us an MD5, compute one.
// This can happen for some providers (e.g., fileblob, which uses the
// local filesystem), but not for the most common Cloud providers
// (S3, GCS, Azure). Although, it can happen for S3 if the blob was uploaded
// via a multi-part upload.
// Although it's unfortunate to have to read the file, it's likely better
// than assuming a delta and re-uploading it.
if len(obj.MD5) == 0 {
r, err := bucket.NewReader(ctx, obj.Key, nil)
if err == nil {
h := md5.New()
if _, err := io.Copy(h, r); err == nil {
obj.MD5 = h.Sum(nil)
}
r.Close()
}
}
retval[obj.Key] = obj
}
return retval, nil
}
// uploadReason is an enum of reasons why a file must be uploaded.
type uploadReason string
const (
reasonUnknown uploadReason = "unknown"
reasonNotFound uploadReason = "not found at target"
reasonForce uploadReason = "--force"
reasonSize uploadReason = "size differs"
reasonMD5Differs uploadReason = "md5 differs"
reasonMD5Missing uploadReason = "remote md5 missing"
)
// fileToUpload represents a single local file that should be uploaded to
// the target.
type fileToUpload struct {
Local *localFile
Reason uploadReason
}
func (u *fileToUpload) String() string {
details := []string{humanize.Bytes(uint64(u.Local.UploadSize))}
if s := u.Local.CacheControl(); s != "" {
details = append(details, fmt.Sprintf("Cache-Control: %q", s))
}
if s := u.Local.ContentEncoding(); s != "" {
details = append(details, fmt.Sprintf("Content-Encoding: %q", s))
}
if s := u.Local.ContentType(); s != "" {
details = append(details, fmt.Sprintf("Content-Type: %q", s))
}
return fmt.Sprintf("%s (%s): %v", u.Local.SlashPath, strings.Join(details, ", "), u.Reason)
}
// findDiffs diffs localFiles vs remoteFiles to see what changes should be
// applied to the remote target. It returns a slice of *fileToUpload and a
// slice of paths for files to delete.
func findDiffs(localFiles map[string]*localFile, remoteFiles map[string]*blob.ListObject, force bool) ([]*fileToUpload, []string) {
var uploads []*fileToUpload
var deletes []string
found := map[string]bool{}
for path, lf := range localFiles {
upload := false
reason := reasonUnknown
if remoteFile, ok := remoteFiles[path]; ok {
// The file exists in remote. Let's see if we need to upload it anyway.
// TODO: We don't register a diff if the metadata (e.g., Content-Type
// header) has changed. This would be difficult/expensive to detect; some
// providers return metadata along with their "List" result, but others
// (notably AWS S3) do not, so gocloud.dev's blob.Bucket doesn't expose
// it in the list result. It would require a separate request per blob
// to fetch. At least for now, we work around this by documenting it and
// providing a "force" flag (to re-upload everything) and a "force" bool
// per matcher (to re-upload all files in a matcher whose headers may have
// changed).
// Idea: extract a sample set of 1 file per extension + 1 file per matcher
// and check those files?
if force {
upload = true
reason = reasonForce
} else if lf.Force() {
upload = true
reason = reasonForce
} else if lf.UploadSize != remoteFile.Size {
upload = true
reason = reasonSize
} else if len(remoteFile.MD5) == 0 {
// This shouldn't happen unless the remote didn't give us an MD5 hash
// from List, AND we failed to compute one by reading the remote file.
// Default to considering the files different.
upload = true
reason = reasonMD5Missing
} else if !bytes.Equal(lf.MD5(), remoteFile.MD5) {
upload = true
reason = reasonMD5Differs
} else {
// Nope! Leave uploaded = false.
}
found[path] = true
} else {
// The file doesn't exist in remote.
upload = true
reason = reasonNotFound
}
if upload {
jww.DEBUG.Printf("%s needs to be uploaded: %v\n", path, reason)
uploads = append(uploads, &fileToUpload{lf, reason})
} else {
jww.DEBUG.Printf("%s exists at target and does not need to be uploaded", path)
}
}
// Remote files that weren't found locally should be deleted.
for path := range remoteFiles {
if !found[path] {
deletes = append(deletes, path)
}
}
return uploads, deletes
}
// applyOrdering returns an ordered slice of slices of uploads.
//
// The returned slice will have length len(ordering)+1.
//
// The subslice at index i, for i = 0 ... len(ordering)-1, will have all of the
// uploads whose Local.SlashPath matched the regex at ordering[i] (but not any
// previous ordering regex).
// The subslice at index len(ordering) will have the remaining uploads that
// didn't match any ordering regex.
//
// The subslices are sorted by Local.SlashPath.
func applyOrdering(ordering []*regexp.Regexp, uploads []*fileToUpload) [][]*fileToUpload {
// Sort the whole slice by Local.SlashPath first.
sort.Slice(uploads, func(i, j int) bool { return uploads[i].Local.SlashPath < uploads[j].Local.SlashPath })
retval := make([][]*fileToUpload, len(ordering)+1)
for _, u := range uploads {
matched := false
for i, re := range ordering {
if re.MatchString(u.Local.SlashPath) {
retval[i] = append(retval[i], u)
matched = true
break
}
}
if !matched {
retval[len(ordering)] = append(retval[len(ordering)], u)
}
}
return retval
}