diff --git a/config/constants.go b/config/constants.go
new file mode 100644
index 0000000..f1c4f59
--- /dev/null
+++ b/config/constants.go
@@ -0,0 +1,79 @@
+
+package config
+
+import (
+	"time"
+)
+
+// Reason of backing to source.
+const (
+	BackSourceReasonNone          = 0
+	BackSourceReasonRegisterFail  = 1
+	BackSourceReasonMd5NotMatch   = 2
+	BackSourceReasonDownloadError = 3
+	BackSourceReasonNoSpace       = 4
+	BackSourceReasonInitError     = 5
+	BackSourceReasonWriteError    = 6
+	BackSourceReasonHostSysError  = 7
+	BackSourceReasonNodeEmpty     = 8
+	BackSourceReasonSourceError   = 10
+	BackSourceReasonUserSpecified = 100
+	ForceNotBackSourceAddition    = 1000
+)
+
+// Download pattern.
+const (
+	PatternP2P      = "p2p"
+	PatternSeedPeer = "seed-peer"
+	PatternSource   = "source"
+)
+
+//// Download limit.
+//const (
+//	DefaultPerPeerDownloadLimit = 20 * unit.MB
+//	DefaultTotalDownloadLimit   = 100 * unit.MB
+//	DefaultUploadLimit          = 100 * unit.MB
+//	DefaultMinRate              = 20 * unit.MB
+//)
+
+// Others.
+const (
+	DefaultTimestampFormat = "2006-01-02 15:04:05"
+	SchemaHTTP             = "http"
+
+	DefaultTaskExpireTime  = 6 * time.Hour
+	DefaultGCInterval      = 1 * time.Minute
+	DefaultDaemonAliveTime = 5 * time.Minute
+	DefaultScheduleTimeout = 5 * time.Minute
+	DefaultDownloadTimeout = 5 * time.Minute
+
+	DefaultSchedulerSchema = "http"
+	DefaultSchedulerIP     = "127.0.0.1"
+	DefaultSchedulerPort   = 8002
+
+	DefaultPieceChanSize     = 16
+	DefaultObjectMaxReplicas = 3
+)
+
+
+// Dfcache subcommand names.
+const (
+	CmdStat   = "stat"
+	CmdImport = "import"
+	CmdExport = "export"
+	CmdDelete = "delete"
+)
+
+// Service defalut port of listening.
+const (
+	DefaultEndPort                = 65535
+	DefaultPeerStartPort          = 65000
+	DefaultUploadStartPort        = 65002
+	DefaultObjectStorageStartPort = 65004
+	DefaultHealthyStartPort       = 40901
+)
+
+var (
+	// DefaultCertValidityPeriod is default validity period of certificate.
+	DefaultCertValidityPeriod = 180 * 24 * time.Hour
+)
diff --git a/config/dfstore.go b/config/dfstore.go
new file mode 100644
index 0000000..946a442
--- /dev/null
+++ b/config/dfstore.go
@@ -0,0 +1,52 @@
+
+
+package config
+
+import (
+	"errors"
+	"fmt"
+	"net/url"
+)
+
+type DfstoreConfig struct {
+	// Address of the object storage service.
+	Endpoint string `yaml:"endpoint,omitempty" mapstructure:"endpoint,omitempty"`
+
+	// Filter is used to generate a unique Task ID by
+	// filtering unnecessary query params in the URL,
+	// it is separated by & character.
+	Filter string `yaml:"filter,omitempty" mapstructure:"filter,omitempty"`
+
+	// Mode is the mode in which the backend is written,
+	// including WriteBack and AsyncWriteBack.
+	Mode int `yaml:"mode,omitempty" mapstructure:"mode,omitempty"`
+
+	// MaxReplicas is the maximum number of
+	// replicas of an object cache in seed peers.
+	MaxReplicas int `yaml:"maxReplicas,omitempty" mapstructure:"mode,maxReplicas"`
+}
+
+// New dfstore configuration.
+func NewDfstore() *DfstoreConfig {
+	url := url.URL{
+		Scheme: "http",
+		Host:   fmt.Sprintf("%s:%d", "127.0.0.1", DefaultObjectStorageStartPort),
+	}
+
+	return &DfstoreConfig{
+		Endpoint:    url.String(),
+		MaxReplicas: DefaultObjectMaxReplicas,
+	}
+}
+
+func (cfg *DfstoreConfig) Validate() error {
+	if cfg.Endpoint == "" {
+		return errors.New("dfstore requires parameter endpoint")
+	}
+
+	if _, err := url.ParseRequestURI(cfg.Endpoint); err != nil {
+		return fmt.Errorf("invalid endpoint: %w", err)
+	}
+
+	return nil
+}
diff --git a/config/headers.go b/config/headers.go
new file mode 100644
index 0000000..9a27296
--- /dev/null
+++ b/config/headers.go
@@ -0,0 +1,32 @@
+/*
+ *     Copyright 2020 The Dragonfly 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 config
+
+const (
+	HeaderDragonflyFilter = "X-Dragonfly-Filter"
+	HeaderDragonflyPeer   = "X-Dragonfly-Peer"
+	HeaderDragonflyTask   = "X-Dragonfly-Task"
+	HeaderDragonflyRange  = "X-Dragonfly-Range"
+	// HeaderDragonflyTag different HeaderDragonflyTag for the same url will be divided into different P2P overlay
+	HeaderDragonflyTag = "X-Dragonfly-Tag"
+	// HeaderDragonflyApplication is used for statistics and traffic control
+	HeaderDragonflyApplication = "X-Dragonfly-Application"
+	// HeaderDragonflyRegistry is used for dynamic registry mirrors.
+	HeaderDragonflyRegistry = "X-Dragonfly-Registry"
+	// HeaderDragonflyObjectMetaDigest is used for digest of object storage.
+	HeaderDragonflyObjectMetaDigest = "X-Dragonfly-Object-Meta-Digest"
+)
diff --git a/dfstore/dfstore.go b/dfstore/dfstore.go
new file mode 100644
index 0000000..8d176da
--- /dev/null
+++ b/dfstore/dfstore.go
@@ -0,0 +1,322 @@
+package dfstore
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"github.com/go-http-utils/headers"
+	"io"
+	"net/http"
+	"net/url"
+	"path"
+	"strconv"
+	"urchinfs/config"
+	pkgobjectstorage "urchinfs/objectstorage"
+)
+
+// Dfstore is the interface used for object storage.
+type Dfstore interface {
+
+	// GetUrfsMetadataRequestWithContext returns *http.Request of getting Urfs metadata.
+	GetUrfsMetadataRequestWithContext(ctx context.Context, input *GetUrfsMetadataInput, isDir bool) (*http.Request, error)
+
+	// GetUrfsMetadataWithContext returns matedata of Urfs.
+	GetUrfsMetadataWithContext(ctx context.Context, input *GetUrfsMetadataInput, isDir bool) (*pkgobjectstorage.ObjectMetadata, error)
+
+	// GetUrfsRequestWithContext returns *http.Request of getting Urfs.
+	GetUrfsRequestWithContext(ctx context.Context, input *GetUrfsInput, isDir bool) (*http.Request, error)
+
+	// GetUrfsWithContext returns data of Urfs.
+	GetUrfsWithContext(ctx context.Context, input *GetUrfsInput, isDir bool) (io.ReadCloser, error)
+
+	// GetUrfsStatusRequestWithContext returns *http.Request of getting Urfs status.
+	GetUrfsStatusRequestWithContext(ctx context.Context, input *GetUrfsInput, isDir bool) (*http.Request, error)
+
+	// GetUrfsStatusWithContext returns schedule status of Urfs.
+	GetUrfsStatusWithContext(ctx context.Context, input *GetUrfsInput, isDir bool) (io.ReadCloser, error)
+}
+
+// dfstore provides object storage function.
+type dfstore struct {
+	endpoint   string
+	httpClient *http.Client
+}
+
+// Option is a functional option for configuring the dfstore.
+type Option func(dfs *dfstore)
+
+// New dfstore instance.
+func New(endpoint string, options ...Option) Dfstore {
+	dfs := &dfstore{
+		endpoint:   endpoint,
+		httpClient: http.DefaultClient,
+	}
+
+	for _, opt := range options {
+		opt(dfs)
+	}
+
+	return dfs
+}
+
+// GetUrfsMetadataInput is used to construct request of getting object metadata.
+type GetUrfsMetadataInput struct {
+
+	// Endpoint is endpoint name.
+	Endpoint string
+
+	// BucketName is bucket name.
+	BucketName string
+
+	// ObjectKey is object key.
+	ObjectKey string
+
+	// DstPeer is target peerHost.
+	DstPeer string
+}
+
+// Validate validates GetUrfsMetadataInput fields.
+func (i *GetUrfsMetadataInput) Validate() error {
+
+	if i.Endpoint == "" {
+		return errors.New("invalid Endpoint")
+
+	}
+
+	if i.BucketName == "" {
+		return errors.New("invalid BucketName")
+
+	}
+
+	if i.ObjectKey == "" {
+		return errors.New("invalid ObjectKey")
+	}
+
+	return nil
+}
+
+// GetObjectMetadataRequestWithContext returns *http.Request of getting object metadata.
+func (dfs *dfstore) GetUrfsMetadataRequestWithContext(ctx context.Context, input *GetUrfsMetadataInput, isDir bool) (*http.Request, error) {
+	if err := input.Validate(); err != nil {
+		return nil, err
+	}
+
+	dstUrl := url.URL{
+		Scheme: "http",
+		Host:   fmt.Sprintf("%s", input.DstPeer),
+	}
+
+	u, err := url.Parse(dstUrl.String())
+	if err != nil {
+		return nil, err
+	}
+
+	u.Path = path.Join("buckets", input.BucketName+"."+input.Endpoint, "objects", input.ObjectKey)
+	req, err := http.NewRequestWithContext(ctx, http.MethodHead, u.String(), nil)
+	if err != nil {
+		return nil, err
+	}
+
+	return req, nil
+}
+
+// GetObjectMetadataWithContext returns metadata of object.
+func (dfs *dfstore) GetUrfsMetadataWithContext(ctx context.Context, input *GetUrfsMetadataInput, isDir bool) (*pkgobjectstorage.ObjectMetadata, error) {
+	req, err := dfs.GetUrfsMetadataRequestWithContext(ctx, input, isDir)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := dfs.httpClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode/100 != 2 {
+		return nil, fmt.Errorf("bad response status %s", resp.Status)
+	}
+
+	contentLength, err := strconv.ParseInt(resp.Header.Get(headers.ContentLength), 10, 64)
+	if err != nil {
+		return nil, err
+	}
+
+	return &pkgobjectstorage.ObjectMetadata{
+		ContentDisposition: resp.Header.Get(headers.ContentDisposition),
+		ContentEncoding:    resp.Header.Get(headers.ContentEncoding),
+		ContentLanguage:    resp.Header.Get(headers.ContentLanguage),
+		ContentLength:      int64(contentLength),
+		ContentType:        resp.Header.Get(headers.ContentType),
+		ETag:               resp.Header.Get(headers.ContentType),
+		Digest:             resp.Header.Get(config.HeaderDragonflyObjectMetaDigest),
+	}, nil
+}
+
+// GetUrfsInput is used to construct request of getting object.
+type GetUrfsInput struct {
+
+	// Endpoint is endpoint name.
+	Endpoint string
+
+	// BucketName is bucket name.
+	BucketName string
+
+	// ObjectKey is object key.
+	ObjectKey string
+
+	// Filter is used to generate a unique Task ID by
+	// filtering unnecessary query params in the URL,
+	// it is separated by & character.
+	Filter string
+
+	// Range is the HTTP range header.
+	Range string
+
+	// DstPeer is target peerHost.
+	DstPeer string
+
+	// Overwrite force overwrite flag
+	Overwrite bool
+}
+
+// GetObjectWithContext returns data of object.
+func (dfs *dfstore) GetUrfsWithContext(ctx context.Context, input *GetUrfsInput, isDir bool) (io.ReadCloser, error) {
+	req, err := dfs.GetUrfsRequestWithContext(ctx, input, isDir)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := dfs.httpClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	if resp.StatusCode/100 != 2 {
+		return nil, fmt.Errorf("bad response status %s", resp.Status)
+	}
+
+	return resp.Body, nil
+}
+
+// GetObjectRequestWithContext returns *http.Request of getting object.
+func (dfs *dfstore) GetUrfsRequestWithContext(ctx context.Context, input *GetUrfsInput, isDir bool) (*http.Request, error) {
+	if err := input.Validate(); err != nil {
+		return nil, err
+	}
+	dstUrl := url.URL{
+		Scheme: "http",
+		Host:   fmt.Sprintf("%s", input.DstPeer),
+	}
+
+	u, err := url.Parse(dstUrl.String())
+	if err != nil {
+		return nil, err
+	}
+
+	if isDir {
+		u.Path = path.Join("buckets", input.BucketName+"."+input.Endpoint, "cache_folder", input.ObjectKey)
+	} else {
+		u.Path = path.Join("buckets", input.BucketName+"."+input.Endpoint, "cache_object", input.ObjectKey)
+	}
+
+	query := u.Query()
+	if input.Filter != "" {
+		query.Set("filter", input.Filter)
+	}
+
+	if !isDir && input.Overwrite {
+		query.Set("overwrite", "1")
+	}
+	u.RawQuery = query.Encode()
+	println("u.string", u.String())
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, u.String(), nil)
+	if err != nil {
+		return nil, err
+	}
+
+	if input.Range != "" {
+		req.Header.Set(headers.Range, input.Range)
+	}
+
+	return req, nil
+}
+
+// Validate validates GetUrfsInput fields.
+func (i *GetUrfsInput) Validate() error {
+
+	if i.Endpoint == "" {
+		return errors.New("invalid Endpoint")
+
+	}
+
+	if i.BucketName == "" {
+		return errors.New("invalid BucketName")
+
+	}
+
+	if i.ObjectKey == "" {
+		return errors.New("invalid ObjectKey")
+	}
+
+	return nil
+}
+
+// GetUrfsStatusWithContext returns schedule task status.
+func (dfs *dfstore) GetUrfsStatusWithContext(ctx context.Context, input *GetUrfsInput, isDir bool) (io.ReadCloser, error) {
+	req, err := dfs.GetUrfsStatusRequestWithContext(ctx, input, isDir)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := dfs.httpClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	if resp.StatusCode/100 != 2 {
+		return nil, fmt.Errorf("bad response status %s", resp.Status)
+	}
+
+	return resp.Body, nil
+}
+
+// GetObjectStatusRequestWithContext returns *http.Request of check schedule task status.
+func (dfs *dfstore) GetUrfsStatusRequestWithContext(ctx context.Context, input *GetUrfsInput, isDir bool) (*http.Request, error) {
+	if err := input.Validate(); err != nil {
+		return nil, err
+	}
+
+	dstUrl := url.URL{
+		Scheme: "http",
+		Host:   fmt.Sprintf("%s", input.DstPeer),
+	}
+
+	u, err := url.Parse(dstUrl.String())
+	if err != nil {
+		return nil, err
+	}
+
+	if isDir {
+		u.Path = path.Join("buckets", input.BucketName+"."+input.Endpoint, "check_folder", input.ObjectKey)
+	} else {
+		u.Path = path.Join("buckets", input.BucketName+"."+input.Endpoint, "check_object", input.ObjectKey)
+	}
+
+	query := u.Query()
+	if input.Filter != "" {
+		query.Set("filter", input.Filter)
+	}
+	u.RawQuery = query.Encode()
+	//println("u.string ", u.String())
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, u.String(), nil)
+	if err != nil {
+		return nil, err
+	}
+
+	if input.Range != "" {
+		req.Header.Set(headers.Range, input.Range)
+	}
+
+	return req, nil
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..63edb52
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,7 @@
+module urchinfs
+
+go 1.18
+
+require github.com/go-http-utils/headers v0.0.0-20181008091004-fed159eddc2a
+
+require github.com/stretchr/testify v1.8.0 // indirect
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..c8faa9c
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,16 @@
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/go-http-utils/headers v0.0.0-20181008091004-fed159eddc2a h1:v6zMvHuY9yue4+QkG/HQ/W67wvtQmWJ4SDo9aK/GIno=
+github.com/go-http-utils/headers v0.0.0-20181008091004-fed159eddc2a/go.mod h1:I79BieaU4fxrw4LMXby6q5OS9XnoR9UIKLOzDFjUmuw=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0 h1:pSgiaMZlXftHpm5L7V1+rVB+AZJydKsMxsQBIJw4PKk=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/main b/main
new file mode 100644
index 0000000..9c533ff
Binary files /dev/null and b/main differ
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..13534ad
--- /dev/null
+++ b/main.go
@@ -0,0 +1,93 @@
+package main
+
+import (
+	"fmt"
+	"time"
+	"urchinfs/urchin"
+)
+
+func trySchedule(sourceURL, endpoint, bucket, objectKey, dstPeer string) {
+	println("new request dstPeer: ", dstPeer)
+	urfs := urchin.New()
+	//scheduleResult, err := urfs.ScheduleDataToPeer(sourceURL, dstPeer)
+	//if err != nil {
+	//	println(err.Error())
+	//}
+	//fmt.Printf("ScheduleDataToPeer StatusCode:%v %v %v %v\n", scheduleResult.StatusCode, scheduleResult.DataEndpoint, scheduleResult.DataRoot, scheduleResult.DataPath)
+	//
+	//checkResult, err := urfs.CheckScheduleTaskStatus(sourceURL, dstPeer)
+	//if err != nil {
+	//	println(err.Error())
+	//}
+	//
+	//fmt.Printf("checkResult StatusCode:%v %v %v %v\n", checkResult.StatusCode, checkResult.DataEndpoint, checkResult.DataRoot, checkResult.DataPath)
+
+	overwrite := true
+	scheduleResult, err := urfs.ScheduleDataToPeerByKey(endpoint, bucket, objectKey, dstPeer, overwrite)
+	if err != nil {
+		println(err.Error())
+	}
+	fmt.Printf("ScheduleDataToPeerByKey StatusCode:%v %v %v %v\n", scheduleResult.StatusCode, scheduleResult.DataEndpoint, scheduleResult.DataRoot, scheduleResult.DataPath)
+
+	time.Sleep(time.Second * 2)
+
+	scheduleResult, err = urfs.CheckScheduleTaskStatusByKey(endpoint, bucket, objectKey, dstPeer)
+	if err != nil {
+		println(err.Error())
+	}
+	fmt.Printf("CheckScheduleTaskStatusByKey StatusCode:%v StatusMsg:%v\n", scheduleResult.StatusCode, scheduleResult.StatusMsg)
+}
+
+func tryScheduleDir(endpoint, bucket, objectKey, dstPeer string) {
+	println("new request dstPeer: ", dstPeer)
+	urfs := urchin.New()
+
+	//scheduleResult, err := urfs.ScheduleDirToPeerByKey(endpoint, bucket, objectKey, dstPeer)
+	//if err != nil {
+	//	print(err.Error())
+	//	return
+	//}
+
+	//fmt.Printf("ScheduleDataToPeerByKey StatusCode:%v %v %v %v\n", scheduleResult.StatusCode, scheduleResult.DataEndpoint, scheduleResult.DataRoot, scheduleResult.DataPath)
+
+	scheduleResult, err := urfs.CheckScheduleDirTaskStatusByKey(endpoint, bucket, objectKey, dstPeer)
+	if err != nil {
+		print(err.Error())
+		return
+	}
+	fmt.Printf("CheckScheduleTaskStatusByKey StatusCode:%v %v %v %v\n", scheduleResult.StatusCode, scheduleResult.DataEndpoint, scheduleResult.DataRoot, scheduleResult.DataPath)
+}
+
+func main() {
+
+	sourceURL := "urfs://obs.cn-south-222.ai.pcl.cn/urchincache/glin/demo_x/object_detection3/code/openi_resource.version"
+	endpoint := "obs.cn-central-231.xckpjs.com"
+	bucket := "urchincache"
+	objectKey := "glin/demo_x/object_detection3/code/openi_resource.version"
+	dstPeer := "192.168.242.42:31814"
+	trySchedule(sourceURL, endpoint, bucket, objectKey, dstPeer)
+	//sourceURL2 := "urfs://11276.c8befbc1301665ba2dc5b2826f8dca1e.ac.sugon.com/work-home-denglf-denglf/code.rar"
+	//endpoint2 := "obs.cn-south-222.ai.pcl.cn"
+
+	//bucket2 := "urchincache"
+	//objectKey2 := "yangxzh/object-detection-image.zip"
+	//dstPeer2 := "192.168.207.91:65004"
+
+	//bucket2 := "open-data"
+	//objectKey2 := "attachment/9/6/96177b0c-6f84-4550-b293-09c206baf811/MNISTData.zip"
+	//dstPeer2 := "192.168.207.91:65004"
+
+	//dstPeer2 := "192.168.242.25:65004"
+	//trySchedule(sourceURL2, endpoint2, bucket2, objectKey2, dstPeer2)
+	//endpoint := "192.168.242.23:31311"
+	//bucket := "grampus"
+	//objectKey := "job/wangj2023031409t5509373540/output/"
+	//dstPeer := "192.168.242.27:65004"
+	// schedule dir example
+	//endpoint := "192.168.242.23:31311"
+	//bucket := "grampus"
+	//objectKey := "/job/cheny2023030215t5435897690/output"
+	//dstPeer := "192.168.242.42:65004"
+	//tryScheduleDir(endpoint, bucket, objectKey, dstPeer)
+
+}
diff --git a/objectstorage/objectstorage.go b/objectstorage/objectstorage.go
new file mode 100644
index 0000000..2fb1774
--- /dev/null
+++ b/objectstorage/objectstorage.go
@@ -0,0 +1,32 @@
+
+//go:generate mockgen -destination mocks/objectstorage_mock.go -source objectstorage.go -package mocks
+
+package objectstorage
+
+type ObjectMetadata struct {
+	// Key is object key.
+	Key string
+
+	// ContentDisposition is Content-Disposition header.
+	ContentDisposition string
+
+	// ContentEncoding is Content-Encoding header.
+	ContentEncoding string
+
+	// ContentLanguage is Content-Language header.
+	ContentLanguage string
+
+	// ContentLanguage is Content-Length header.
+	ContentLength int64
+
+	// ContentType is Content-Type header.
+	ContentType string
+
+	// ETag is ETag header.
+	ETag string
+
+	// Digest is object digest.
+	Digest string
+}
+
+
diff --git a/urchin/urchinfs.go b/urchin/urchinfs.go
new file mode 100644
index 0000000..97d2e56
--- /dev/null
+++ b/urchin/urchinfs.go
@@ -0,0 +1,349 @@
+package urchin
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"net/url"
+	"strconv"
+	"strings"
+	"urchinfs/config"
+	urfs "urchinfs/dfstore"
+)
+
+type Urchinfs interface {
+
+	// schedule source dataset to target peer
+	ScheduleDataToPeer(sourceUrl, destPeerHost string) (*PeerResult, error)
+
+	// check schedule data to peer task status
+	CheckScheduleTaskStatus(sourceUrl, destPeerHost string) (*PeerResult, error)
+
+	ScheduleDataToPeerByKey(endpoint, bucketName, objectKey, destPeerHost string, overwrite bool) (*PeerResult, error)
+
+	CheckScheduleTaskStatusByKey(endpoint, bucketName, objectKey, destPeerHost string) (*PeerResult, error)
+
+	ScheduleDirToPeerByKey(endpoint, bucketName, objectKey, destPeerHost string) (*PeerResult, error)
+
+	CheckScheduleDirTaskStatusByKey(endpoint, bucketName, objectKey, destPeerHost string) (*PeerResult, error)
+}
+
+type urchinfs struct {
+	// Initialize default urfs config.
+	cfg *config.DfstoreConfig
+}
+
+// New urchinfs instance.
+func New() Urchinfs {
+
+	urfs := &urchinfs{
+		cfg: config.NewDfstore(),
+	}
+	return urfs
+}
+
+const (
+	// UrfsScheme if the scheme of object storage.
+	UrfsScheme = "urfs"
+)
+
+func (urfs *urchinfs) ScheduleDataToPeer(sourceUrl, destPeerHost string) (*PeerResult, error) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	if err := urfs.cfg.Validate(); err != nil {
+		return nil, err
+	}
+
+	if err := validateSchedulelArgs(sourceUrl, destPeerHost); err != nil {
+		return nil, err
+	}
+
+	// Copy object storage to local file.
+	endpoint, bucketName, objectKey, err := parseUrfsURL(sourceUrl)
+	if err != nil {
+		return nil, err
+	}
+	peerResult, err := processScheduleDataToPeer(ctx, urfs.cfg, endpoint, bucketName, objectKey, destPeerHost, false)
+	if err != nil {
+		return nil, err
+	}
+
+	return peerResult, err
+}
+
+func (urfs *urchinfs) ScheduleDataToPeerByKey(endpoint, bucketName, objectKey, destPeerHost string, overwrite bool) (*PeerResult, error) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	peerResult, err := processScheduleDataToPeer(ctx, urfs.cfg, endpoint, bucketName, objectKey, destPeerHost, overwrite)
+	if err != nil {
+		return nil, err
+	}
+
+	return peerResult, err
+}
+
+func (urfs *urchinfs) ScheduleDirToPeerByKey(endpoint, bucketName, objectKey, destPeerHost string) (*PeerResult, error) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	peerResult, err := processScheduleDirToPeer(ctx, urfs.cfg, endpoint, bucketName, objectKey, destPeerHost)
+	if err != nil {
+		return nil, err
+	}
+
+	return peerResult, err
+}
+
+func (urfs *urchinfs) CheckScheduleTaskStatus(sourceUrl, destPeerHost string) (*PeerResult, error) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	if err := urfs.cfg.Validate(); err != nil {
+		return nil, err
+	}
+
+	if err := validateSchedulelArgs(sourceUrl, destPeerHost); err != nil {
+		return nil, err
+	}
+
+	// Copy object storage to local file.
+	endpoint, bucketName, objectKey, err := parseUrfsURL(sourceUrl)
+	if err != nil {
+		return nil, err
+	}
+	peerResult, err := processCheckScheduleTaskStatus(ctx, urfs.cfg, endpoint, bucketName, objectKey, destPeerHost)
+	if err != nil {
+		return nil, err
+	}
+
+	return peerResult, err
+}
+
+func (urfs *urchinfs) CheckScheduleTaskStatusByKey(endpoint, bucketName, objectKey, destPeerHost string) (*PeerResult, error) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	peerResult, err := processCheckScheduleTaskStatus(ctx, urfs.cfg, endpoint, bucketName, objectKey, destPeerHost)
+	if err != nil {
+		return nil, err
+	}
+
+	return peerResult, err
+}
+
+func (urfs *urchinfs) CheckScheduleDirTaskStatusByKey(endpoint, bucketName, objectKey, destPeerHost string) (*PeerResult, error) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	peerResult, err := processCheckScheduleDirTaskStatus(ctx, urfs.cfg, endpoint, bucketName, objectKey, destPeerHost)
+	if err != nil {
+		return nil, err
+	}
+
+	return peerResult, err
+}
+
+// isUrfsURL determines whether the raw url is urfs url.
+func isUrfsURL(rawURL string) bool {
+	u, err := url.ParseRequestURI(rawURL)
+	if err != nil {
+		return false
+	}
+
+	if u.Scheme != UrfsScheme || u.Host == "" || u.Path == "" {
+		return false
+	}
+
+	return true
+}
+
+// Validate copy arguments.
+func validateSchedulelArgs(sourceUrl, destPeer string) error {
+	if !isUrfsURL(sourceUrl) {
+		return errors.New("source url should be urfs:// protocol")
+	}
+
+	return nil
+}
+
+// Parse object storage url. eg: urfs://源数据$endpoint/源数据$bucket/源数据filepath
+func parseUrfsURL(rawURL string) (string, string, string, error) {
+	u, err := url.ParseRequestURI(rawURL)
+	if err != nil {
+		return "", "", "", err
+	}
+
+	if u.Scheme != UrfsScheme {
+		return "", "", "", fmt.Errorf("invalid scheme, e.g. %s://endpoint/bucket_name/object_key", UrfsScheme)
+	}
+
+	if u.Host == "" {
+		return "", "", "", errors.New("empty endpoint name")
+	}
+
+	if u.Path == "" {
+		return "", "", "", errors.New("empty object path")
+	}
+
+	bucket, key, found := strings.Cut(strings.Trim(u.Path, "/"), "/")
+	if found == false {
+		return "", "", "", errors.New("invalid bucket and object key " + u.Path)
+	}
+
+	//println(u.Host, " ", bucket, " ", key)
+
+	return u.Host, bucket, key, nil
+}
+
+// Schedule object storage to peer.
+func processScheduleDataToPeer(ctx context.Context, cfg *config.DfstoreConfig, endpoint, bucketName, objectKey, dstPeer string, overwrite bool) (*PeerResult, error) {
+	dfs := urfs.New(cfg.Endpoint)
+	meta, err := dfs.GetUrfsMetadataWithContext(ctx, &urfs.GetUrfsMetadataInput{
+		Endpoint:   endpoint,
+		BucketName: bucketName,
+		ObjectKey:  objectKey,
+		DstPeer:    dstPeer,
+	}, false)
+	if err != nil {
+		return nil, err
+	}
+
+	reader, err := dfs.GetUrfsWithContext(ctx, &urfs.GetUrfsInput{
+		Endpoint:   endpoint,
+		BucketName: bucketName,
+		ObjectKey:  objectKey,
+		DstPeer:    dstPeer,
+		Overwrite:  overwrite,
+	}, false)
+	if err != nil {
+		return nil, err
+	}
+	defer reader.Close()
+
+	body, err := ioutil.ReadAll(reader)
+
+	var peerResult PeerResult
+	if err == nil {
+		err = json.Unmarshal((body), &peerResult)
+	}
+	peerResult.SignedUrl = strings.ReplaceAll(peerResult.SignedUrl, "\\u0026", "&")
+
+	fileContentLength, err := strconv.ParseInt(peerResult.ContentLength, 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	if fileContentLength != meta.ContentLength {
+		return nil, errors.New("content length inconsistent with meta")
+	}
+
+	return &peerResult, err
+}
+
+// Schedule object storage dir to peer.
+func processScheduleDirToPeer(ctx context.Context, cfg *config.DfstoreConfig, endpoint, bucketName, objectKey, dstPeer string) (*PeerResult, error) {
+	dfs := urfs.New(cfg.Endpoint)
+
+	reader, err := dfs.GetUrfsWithContext(ctx, &urfs.GetUrfsInput{
+		Endpoint:   endpoint,
+		BucketName: bucketName,
+		ObjectKey:  objectKey,
+		DstPeer:    dstPeer,
+	}, true)
+	if err != nil {
+		return nil, err
+	}
+	defer reader.Close()
+
+	body, err := ioutil.ReadAll(reader)
+
+	var peerResult PeerResult
+	if err == nil {
+		err = json.Unmarshal((body), &peerResult)
+	}
+	peerResult.SignedUrl = strings.ReplaceAll(peerResult.SignedUrl, "\\u0026", "&")
+
+	return &peerResult, err
+}
+
+// check schedule task status.
+func processCheckScheduleTaskStatus(ctx context.Context, cfg *config.DfstoreConfig, endpoint, bucketName, objectKey, dstPeer string) (*PeerResult, error) {
+	dfs := urfs.New(cfg.Endpoint)
+	meta, err := dfs.GetUrfsMetadataWithContext(ctx, &urfs.GetUrfsMetadataInput{
+		Endpoint:   endpoint,
+		BucketName: bucketName,
+		ObjectKey:  objectKey,
+		DstPeer:    dstPeer,
+	}, false)
+	if err != nil {
+		return nil, err
+	}
+
+	reader, err := dfs.GetUrfsStatusWithContext(ctx, &urfs.GetUrfsInput{
+		Endpoint:   endpoint,
+		BucketName: bucketName,
+		ObjectKey:  objectKey,
+		DstPeer:    dstPeer,
+	}, false)
+	if err != nil {
+		return nil, err
+	}
+	defer reader.Close()
+
+	body, err := ioutil.ReadAll(reader)
+
+	var peerResult PeerResult
+	if err == nil {
+		err = json.Unmarshal((body), &peerResult)
+	}
+	peerResult.SignedUrl = strings.ReplaceAll(peerResult.SignedUrl, "\\u0026", "&")
+
+	fileContentLength, err := strconv.ParseInt(peerResult.ContentLength, 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	if fileContentLength != meta.ContentLength {
+		return nil, errors.New("content length inconsistent with meta")
+	}
+	return &peerResult, err
+}
+
+// check schedule task status.
+func processCheckScheduleDirTaskStatus(ctx context.Context, cfg *config.DfstoreConfig, endpoint, bucketName, objectKey, dstPeer string) (*PeerResult, error) {
+	dfs := urfs.New(cfg.Endpoint)
+
+	reader, err := dfs.GetUrfsStatusWithContext(ctx, &urfs.GetUrfsInput{
+		Endpoint:   endpoint,
+		BucketName: bucketName,
+		ObjectKey:  objectKey,
+		DstPeer:    dstPeer,
+	}, true)
+	if err != nil {
+		return nil, err
+	}
+	defer reader.Close()
+
+	body, err := ioutil.ReadAll(reader)
+
+	var peerResult PeerResult
+	if err == nil {
+		err = json.Unmarshal((body), &peerResult)
+	}
+	peerResult.SignedUrl = strings.ReplaceAll(peerResult.SignedUrl, "\\u0026", "&")
+	return &peerResult, err
+}
+
+type PeerResult struct {
+	ContentType   string `json:"Content-Type"`
+	ContentLength string `json:"Content-Length"`
+	SignedUrl     string
+	DataRoot      string
+	DataPath      string
+	DataEndpoint  string
+	StatusCode    int
+	StatusMsg     string
+	TaskID        string
+}