git-lfs/tq/manifest.go

package tq

import (
	"sync"

	"github.com/git-lfs/git-lfs/lfsapi"
	"github.com/rubyist/tracerx"
)

const (
	defaultMaxRetries          = 8
	defaultConcurrentTransfers = 3
)

type Manifest struct {
	// MaxRetries is the maximum number of retries a single object can
	// attempt to make before it will be dropped.
	maxRetries           int
	concurrentTransfers  int
	basicTransfersOnly   bool
	tusTransfersAllowed  bool
	downloadAdapterFuncs map[string]NewAdapterFunc
	uploadAdapterFuncs   map[string]NewAdapterFunc
	apiClient            *lfsapi.Client
	tqClient             *tqClient
	mu                   sync.Mutex
}

func (m *Manifest) APIClient() *lfsapi.Client {
	return m.apiClient
}

func (m *Manifest) MaxRetries() int {
	return m.maxRetries
}

func (m *Manifest) ConcurrentTransfers() int {
	return m.concurrentTransfers
}

func (m *Manifest) batchClient() *tqClient {
	return m.tqClient
}

func NewManifest() *Manifest {
	cli, err := lfsapi.NewClient(nil, nil)
	if err != nil {
		tracerx.Printf("unable to init tq.Manifest: %s", err)
		return nil
	}

	return NewManifestWithClient(cli)
}

func NewManifestWithClient(apiClient *lfsapi.Client) *Manifest {
	m := &Manifest{
		apiClient:            apiClient,
		tqClient:             &tqClient{Client: apiClient},
		downloadAdapterFuncs: make(map[string]NewAdapterFunc),
		uploadAdapterFuncs:   make(map[string]NewAdapterFunc),
	}

	var tusAllowed bool
	if git := apiClient.GitEnv(); git != nil {
		if v := git.Int("lfs.transfer.maxretries", 0); v > 0 {
			m.maxRetries = v
		}
		if v := git.Int("lfs.concurrenttransfers", 0); v > 0 {
			m.concurrentTransfers = v
		}
		m.basicTransfersOnly = git.Bool("lfs.basictransfersonly", false)
		tusAllowed = git.Bool("lfs.tustransfers", false)
		configureCustomAdapters(git, m)
	}

	if m.maxRetries < 1 {
		m.maxRetries = defaultMaxRetries
	}

	if m.concurrentTransfers < 1 {
		m.concurrentTransfers = defaultConcurrentTransfers
	}

	configureBasicDownloadAdapter(m)
	configureBasicUploadAdapter(m)
	if tusAllowed {
		configureTusAdapter(m)
	}
	return m
}

// GetAdapterNames returns a list of the names of adapters available to be created
func (m *Manifest) GetAdapterNames(dir Direction) []string {
	switch dir {
	case Upload:
		return m.GetUploadAdapterNames()
	case Download:
		return m.GetDownloadAdapterNames()
	}
	return nil
}

// GetDownloadAdapterNames returns a list of the names of download adapters available to be created
func (m *Manifest) GetDownloadAdapterNames() []string {
	return m.getAdapterNames(m.downloadAdapterFuncs)
}

// GetUploadAdapterNames returns a list of the names of upload adapters available to be created
func (m *Manifest) GetUploadAdapterNames() []string {
	return m.getAdapterNames(m.uploadAdapterFuncs)
}

// getAdapterNames returns a list of the names of adapters available to be created
func (m *Manifest) getAdapterNames(adapters map[string]NewAdapterFunc) []string {
	if m.basicTransfersOnly {
		return []string{BasicAdapterName}
	}

	m.mu.Lock()
	defer m.mu.Unlock()

	ret := make([]string, 0, len(adapters))
	for n, _ := range adapters {
		ret = append(ret, n)
	}
	return ret
}

// RegisterNewTransferAdapterFunc registers a new function for creating upload
// or download adapters. If a function with that name & direction is already
// registered, it is overridden
func (m *Manifest) RegisterNewAdapterFunc(name string, dir Direction, f NewAdapterFunc) {
	m.mu.Lock()
	defer m.mu.Unlock()

	switch dir {
	case Upload:
		m.uploadAdapterFuncs[name] = f
	case Download:
		m.downloadAdapterFuncs[name] = f
	}
}

// Create a new adapter by name and direction; default to BasicAdapterName if doesn't exist
func (m *Manifest) NewAdapterOrDefault(name string, dir Direction) Adapter {
	if len(name) == 0 {
		name = BasicAdapterName
	}

	a := m.NewAdapter(name, dir)
	if a == nil {
		tracerx.Printf("Defaulting to basic transfer adapter since %q did not exist", name)
		a = m.NewAdapter(BasicAdapterName, dir)
	}
	return a
}

// Create a new adapter by name and direction, or nil if doesn't exist
func (m *Manifest) NewAdapter(name string, dir Direction) Adapter {
	m.mu.Lock()
	defer m.mu.Unlock()

	switch dir {
	case Upload:
		if u, ok := m.uploadAdapterFuncs[name]; ok {
			return u(name, dir)
		}
	case Download:
		if d, ok := m.downloadAdapterFuncs[name]; ok {
			return d(name, dir)
		}
	}
	return nil
}

// Create a new download adapter by name, or BasicAdapterName if doesn't exist
func (m *Manifest) NewDownloadAdapter(name string) Adapter {
	return m.NewAdapterOrDefault(name, Download)
}

// Create a new upload adapter by name, or BasicAdapterName if doesn't exist
func (m *Manifest) NewUploadAdapter(name string) Adapter {
	return m.NewAdapterOrDefault(name, Upload)
}

// Env is any object with a config.Environment interface.
type Env interface {
	Get(key string) (val string, ok bool)
	Bool(key string, def bool) (val bool)
	Int(key string, def int) (val int)
	All() map[string]string
}