blob: 6b50934050177ffcd35cf2dbd6f9ef0c3133c75b [file] [log] [blame]
package object
import (
"bufio"
"bytes"
"context"
"errors"
"fmt"
"io"
"strings"
"golang.org/x/crypto/openpgp"
"gopkg.in/src-d/go-git.v4/plumbing"
"gopkg.in/src-d/go-git.v4/plumbing/storer"
"gopkg.in/src-d/go-git.v4/utils/ioutil"
)
const (
beginpgp string = "-----BEGIN PGP SIGNATURE-----"
endpgp string = "-----END PGP SIGNATURE-----"
headerpgp string = "gpgsig"
)
// Hash represents the hash of an object
type Hash plumbing.Hash
// Commit points to a single tree, marking it as what the project looked like
// at a certain point in time. It contains meta-information about that point
// in time, such as a timestamp, the author of the changes since the last
// commit, a pointer to the previous commit(s), etc.
// http://shafiulazam.com/gitbook/1_the_git_object_model.html
type Commit struct {
// Hash of the commit object.
Hash plumbing.Hash
// Author is the original author of the commit.
Author Signature
// Committer is the one performing the commit, might be different from
// Author.
Committer Signature
// PGPSignature is the PGP signature of the commit.
PGPSignature string
// Message is the commit message, contains arbitrary text.
Message string
// TreeHash is the hash of the root tree of the commit.
TreeHash plumbing.Hash
// ParentHashes are the hashes of the parent commits of the commit.
ParentHashes []plumbing.Hash
s storer.EncodedObjectStorer
}
// GetCommit gets a commit from an object storer and decodes it.
func GetCommit(s storer.EncodedObjectStorer, h plumbing.Hash) (*Commit, error) {
o, err := s.EncodedObject(plumbing.CommitObject, h)
if err != nil {
return nil, err
}
return DecodeCommit(s, o)
}
// DecodeCommit decodes an encoded object into a *Commit and associates it to
// the given object storer.
func DecodeCommit(s storer.EncodedObjectStorer, o plumbing.EncodedObject) (*Commit, error) {
c := &Commit{s: s}
if err := c.Decode(o); err != nil {
return nil, err
}
return c, nil
}
// Tree returns the Tree from the commit.
func (c *Commit) Tree() (*Tree, error) {
return GetTree(c.s, c.TreeHash)
}
// PatchContext returns the Patch between the actual commit and the provided one.
// Error will be return if context expires. Provided context must be non-nil.
func (c *Commit) PatchContext(ctx context.Context, to *Commit) (*Patch, error) {
fromTree, err := c.Tree()
if err != nil {
return nil, err
}
toTree, err := to.Tree()
if err != nil {
return nil, err
}
return fromTree.PatchContext(ctx, toTree)
}
// Patch returns the Patch between the actual commit and the provided one.
func (c *Commit) Patch(to *Commit) (*Patch, error) {
return c.PatchContext(context.Background(), to)
}
// Parents return a CommitIter to the parent Commits.
func (c *Commit) Parents() CommitIter {
return NewCommitIter(c.s,
storer.NewEncodedObjectLookupIter(c.s, plumbing.CommitObject, c.ParentHashes),
)
}
// NumParents returns the number of parents in a commit.
func (c *Commit) NumParents() int {
return len(c.ParentHashes)
}
var ErrParentNotFound = errors.New("commit parent not found")
// Parent returns the ith parent of a commit.
func (c *Commit) Parent(i int) (*Commit, error) {
if len(c.ParentHashes) == 0 || i > len(c.ParentHashes)-1 {
return nil, ErrParentNotFound
}
return GetCommit(c.s, c.ParentHashes[i])
}
// File returns the file with the specified "path" in the commit and a
// nil error if the file exists. If the file does not exist, it returns
// a nil file and the ErrFileNotFound error.
func (c *Commit) File(path string) (*File, error) {
tree, err := c.Tree()
if err != nil {
return nil, err
}
return tree.File(path)
}
// Files returns a FileIter allowing to iterate over the Tree
func (c *Commit) Files() (*FileIter, error) {
tree, err := c.Tree()
if err != nil {
return nil, err
}
return tree.Files(), nil
}
// ID returns the object ID of the commit. The returned value will always match
// the current value of Commit.Hash.
//
// ID is present to fulfill the Object interface.
func (c *Commit) ID() plumbing.Hash {
return c.Hash
}
// Type returns the type of object. It always returns plumbing.CommitObject.
//
// Type is present to fulfill the Object interface.
func (c *Commit) Type() plumbing.ObjectType {
return plumbing.CommitObject
}
// Decode transforms a plumbing.EncodedObject into a Commit struct.
func (c *Commit) Decode(o plumbing.EncodedObject) (err error) {
if o.Type() != plumbing.CommitObject {
return ErrUnsupportedObject
}
c.Hash = o.Hash()
reader, err := o.Reader()
if err != nil {
return err
}
defer ioutil.CheckClose(reader, &err)
r := bufPool.Get().(*bufio.Reader)
defer bufPool.Put(r)
r.Reset(reader)
var message bool
var pgpsig bool
for {
line, err := r.ReadBytes('\n')
if err != nil && err != io.EOF {
return err
}
if pgpsig {
if len(line) > 0 && line[0] == ' ' {
line = bytes.TrimLeft(line, " ")
c.PGPSignature += string(line)
continue
} else {
pgpsig = false
}
}
if !message {
line = bytes.TrimSpace(line)
if len(line) == 0 {
message = true
continue
}
split := bytes.SplitN(line, []byte{' '}, 2)
var data []byte
if len(split) == 2 {
data = split[1]
}
switch string(split[0]) {
case "tree":
c.TreeHash = plumbing.NewHash(string(data))
case "parent":
c.ParentHashes = append(c.ParentHashes, plumbing.NewHash(string(data)))
case "author":
c.Author.Decode(data)
case "committer":
c.Committer.Decode(data)
case headerpgp:
c.PGPSignature += string(data) + "\n"
pgpsig = true
}
} else {
c.Message += string(line)
}
if err == io.EOF {
return nil
}
}
}
// Encode transforms a Commit into a plumbing.EncodedObject.
func (b *Commit) Encode(o plumbing.EncodedObject) error {
return b.encode(o, true)
}
// EncodeWithoutSignature export a Commit into a plumbing.EncodedObject without the signature (correspond to the payload of the PGP signature).
func (b *Commit) EncodeWithoutSignature(o plumbing.EncodedObject) error {
return b.encode(o, false)
}
func (b *Commit) encode(o plumbing.EncodedObject, includeSig bool) (err error) {
o.SetType(plumbing.CommitObject)
w, err := o.Writer()
if err != nil {
return err
}
defer ioutil.CheckClose(w, &err)
if _, err = fmt.Fprintf(w, "tree %s\n", b.TreeHash.String()); err != nil {
return err
}
for _, parent := range b.ParentHashes {
if _, err = fmt.Fprintf(w, "parent %s\n", parent.String()); err != nil {
return err
}
}
if _, err = fmt.Fprint(w, "author "); err != nil {
return err
}
if err = b.Author.Encode(w); err != nil {
return err
}
if _, err = fmt.Fprint(w, "\ncommitter "); err != nil {
return err
}
if err = b.Committer.Encode(w); err != nil {
return err
}
if b.PGPSignature != "" && includeSig {
if _, err = fmt.Fprint(w, "\n"+headerpgp+" "); err != nil {
return err
}
// Split all the signature lines and re-write with a left padding and
// newline. Use join for this so it's clear that a newline should not be
// added after this section, as it will be added when the message is
// printed.
signature := strings.TrimSuffix(b.PGPSignature, "\n")
lines := strings.Split(signature, "\n")
if _, err = fmt.Fprint(w, strings.Join(lines, "\n ")); err != nil {
return err
}
}
if _, err = fmt.Fprintf(w, "\n\n%s", b.Message); err != nil {
return err
}
return err
}
// Stats returns the stats of a commit.
func (c *Commit) Stats() (FileStats, error) {
return c.StatsContext(context.Background())
}
// StatsContext returns the stats of a commit. Error will be return if context
// expires. Provided context must be non-nil.
func (c *Commit) StatsContext(ctx context.Context) (FileStats, error) {
fromTree, err := c.Tree()
if err != nil {
return nil, err
}
toTree := &Tree{}
if c.NumParents() != 0 {
firstParent, err := c.Parents().Next()
if err != nil {
return nil, err
}
toTree, err = firstParent.Tree()
if err != nil {
return nil, err
}
}
patch, err := toTree.PatchContext(ctx, fromTree)
if err != nil {
return nil, err
}
return getFileStatsFromFilePatches(patch.FilePatches()), nil
}
func (c *Commit) String() string {
return fmt.Sprintf(
"%s %s\nAuthor: %s\nDate: %s\n\n%s\n",
plumbing.CommitObject, c.Hash, c.Author.String(),
c.Author.When.Format(DateFormat), indent(c.Message),
)
}
// Verify performs PGP verification of the commit with a provided armored
// keyring and returns openpgp.Entity associated with verifying key on success.
func (c *Commit) Verify(armoredKeyRing string) (*openpgp.Entity, error) {
keyRingReader := strings.NewReader(armoredKeyRing)
keyring, err := openpgp.ReadArmoredKeyRing(keyRingReader)
if err != nil {
return nil, err
}
// Extract signature.
signature := strings.NewReader(c.PGPSignature)
encoded := &plumbing.MemoryObject{}
// Encode commit components, excluding signature and get a reader object.
if err := c.EncodeWithoutSignature(encoded); err != nil {
return nil, err
}
er, err := encoded.Reader()
if err != nil {
return nil, err
}
return openpgp.CheckArmoredDetachedSignature(keyring, er, signature)
}
func indent(t string) string {
var output []string
for _, line := range strings.Split(t, "\n") {
if len(line) != 0 {
line = " " + line
}
output = append(output, line)
}
return strings.Join(output, "\n")
}
// CommitIter is a generic closable interface for iterating over commits.
type CommitIter interface {
Next() (*Commit, error)
ForEach(func(*Commit) error) error
Close()
}
// storerCommitIter provides an iterator from commits in an EncodedObjectStorer.
type storerCommitIter struct {
storer.EncodedObjectIter
s storer.EncodedObjectStorer
}
// NewCommitIter takes a storer.EncodedObjectStorer and a
// storer.EncodedObjectIter and returns a CommitIter that iterates over all
// commits contained in the storer.EncodedObjectIter.
//
// Any non-commit object returned by the storer.EncodedObjectIter is skipped.
func NewCommitIter(s storer.EncodedObjectStorer, iter storer.EncodedObjectIter) CommitIter {
return &storerCommitIter{iter, s}
}
// Next moves the iterator to the next commit and returns a pointer to it. If
// there are no more commits, it returns io.EOF.
func (iter *storerCommitIter) Next() (*Commit, error) {
obj, err := iter.EncodedObjectIter.Next()
if err != nil {
return nil, err
}
return DecodeCommit(iter.s, obj)
}
// ForEach call the cb function for each commit contained on this iter until
// an error appends or the end of the iter is reached. If ErrStop is sent
// the iteration is stopped but no error is returned. The iterator is closed.
func (iter *storerCommitIter) ForEach(cb func(*Commit) error) error {
return iter.EncodedObjectIter.ForEach(func(obj plumbing.EncodedObject) error {
c, err := DecodeCommit(iter.s, obj)
if err != nil {
return err
}
return cb(c)
})
}
func (iter *storerCommitIter) Close() {
iter.EncodedObjectIter.Close()
}