package git import ( "errors" "fmt" "io" "gopkg.in/src-d/go-git.v4/config" "gopkg.in/src-d/go-git.v4/plumbing" "gopkg.in/src-d/go-git.v4/plumbing/format/packfile" "gopkg.in/src-d/go-git.v4/plumbing/protocol/packp" "gopkg.in/src-d/go-git.v4/plumbing/protocol/packp/capability" "gopkg.in/src-d/go-git.v4/plumbing/storer" "gopkg.in/src-d/go-git.v4/plumbing/transport" "gopkg.in/src-d/go-git.v4/plumbing/transport/client" "gopkg.in/src-d/go-git.v4/storage/memory" ) var NoErrAlreadyUpToDate = errors.New("already up-to-date") // Remote represents a connection to a remote repository type Remote struct { c *config.RemoteConfig s Storer // cache fields, there during the connection is open endpoint transport.Endpoint client transport.Client fetchSession transport.FetchPackSession advRefs *packp.AdvRefs refs memory.ReferenceStorage } func newRemote(s Storer, c *config.RemoteConfig) *Remote { return &Remote{s: s, c: c} } // Config return the config func (r *Remote) Config() *config.RemoteConfig { return r.c } // Connect with the endpoint func (r *Remote) Connect() error { if err := r.initClient(); err != nil { return err } var err error r.fetchSession, err = r.client.NewFetchPackSession(r.endpoint) if err != nil { return nil } return r.retrieveAdvertisedReferences() } func (r *Remote) initClient() error { var err error r.endpoint, err = transport.NewEndpoint(r.c.URL) if err != nil { return err } if r.client != nil { return nil } r.client, err = client.NewClient(r.endpoint) if err != nil { return err } return nil } func (r *Remote) retrieveAdvertisedReferences() error { var err error r.advRefs, err = r.fetchSession.AdvertisedReferences() if err != nil { return err } r.refs, err = r.advRefs.AllReferences() return err } // AdvertisedReferences returns the git-upload-pack advertised references. func (r *Remote) AdvertisedReferences() *packp.AdvRefs { return r.advRefs } // Capabilities returns the remote capabilities func (r *Remote) Capabilities() *capability.List { return r.advRefs.Capabilities } // Fetch returns a reader using the request func (r *Remote) Fetch(o *FetchOptions) (err error) { if err := o.Validate(); err != nil { return err } if len(o.RefSpecs) == 0 { o.RefSpecs = r.c.Fetch } refs, err := r.getWantedReferences(o.RefSpecs) if err != nil { return err } if len(refs) == 0 { return NoErrAlreadyUpToDate } req, err := r.buildRequest(r.s, o, refs) if err != nil { return err } reader, err := r.fetchSession.FetchPack(req) if err != nil { return err } defer checkClose(reader, &err) if err := r.updateObjectStorage(reader); err != nil { return err } return r.updateLocalReferenceStorage(o.RefSpecs, refs) } func (r *Remote) getWantedReferences(spec []config.RefSpec) ([]*plumbing.Reference, error) { var refs []*plumbing.Reference iter, err := r.References() if err != nil { return refs, err } wantTags := true for _, s := range spec { if !s.IsWildcard() { wantTags = false break } } return refs, iter.ForEach(func(ref *plumbing.Reference) error { if ref.Type() != plumbing.HashReference { return nil } if !config.MatchAny(spec, ref.Name()) { if !ref.IsTag() || !wantTags { return nil } } _, err := r.s.Object(plumbing.CommitObject, ref.Hash()) if err == plumbing.ErrObjectNotFound { refs = append(refs, ref) return nil } return err }) } func (r *Remote) buildRequest( s storer.ReferenceStorer, o *FetchOptions, refs []*plumbing.Reference, ) (*packp.UploadPackRequest, error) { req := packp.NewUploadPackRequestFromCapabilities(r.advRefs.Capabilities) if o.Depth != 0 { req.Depth = packp.DepthCommits(o.Depth) req.Capabilities.Set(capability.Shallow) } for _, ref := range refs { req.Wants = append(req.Wants, ref.Hash()) } i, err := s.IterReferences() if err != nil { return nil, err } err = i.ForEach(func(ref *plumbing.Reference) error { if ref.Type() != plumbing.HashReference { return nil } req.Haves = append(req.Haves, ref.Hash()) return nil }) return req, err } func (r *Remote) updateObjectStorage(reader io.Reader) error { if sw, ok := r.s.(storer.PackfileWriter); ok { w, err := sw.PackfileWriter() if err != nil { return err } defer w.Close() _, err = io.Copy(w, reader) return err } stream := packfile.NewScanner(reader) d, err := packfile.NewDecoder(stream, r.s) if err != nil { return err } _, err = d.Decode() return err } func (r *Remote) updateLocalReferenceStorage(specs []config.RefSpec, refs []*plumbing.Reference) error { for _, spec := range specs { for _, ref := range refs { if !spec.Match(ref.Name()) { continue } if ref.Type() != plumbing.HashReference { continue } name := spec.Dst(ref.Name()) n := plumbing.NewHashReference(name, ref.Hash()) if err := r.s.SetReference(n); err != nil { return err } } } return r.buildFetchedTags() } func (r *Remote) buildFetchedTags() error { iter, err := r.References() if err != nil { return err } return iter.ForEach(func(ref *plumbing.Reference) error { if !ref.IsTag() { return nil } _, err := r.s.Object(plumbing.AnyObject, ref.Hash()) if err == plumbing.ErrObjectNotFound { return nil } if err != nil { return err } return r.s.SetReference(ref) }) } // Head returns the Reference of the HEAD func (r *Remote) Head() *plumbing.Reference { ref, err := storer.ResolveReference(r.refs, plumbing.HEAD) if err != nil { return nil } return ref } // Reference returns a Reference for a ReferenceName. func (r *Remote) Reference(name plumbing.ReferenceName, resolved bool) (*plumbing.Reference, error) { if resolved { return storer.ResolveReference(r.refs, name) } return r.refs.Reference(name) } // References returns an iterator for all references. func (r *Remote) References() (storer.ReferenceIter, error) { return r.refs.IterReferences() } // Disconnect from the remote and save the config func (r *Remote) Disconnect() error { r.advRefs = nil return r.fetchSession.Close() } func (r *Remote) String() string { fetch := r.c.URL push := r.c.URL return fmt.Sprintf("%s\t%s (fetch)\n%[1]s\t%s (push)", r.c.Name, fetch, push) }