Define the controller/manager interface for artifact and tag

1. Define the controller/manager interface for artifact and tag
    2. Provide a null implementation for artifact manager

Signed-off-by: Wenkai Yin <yinw@vmware.com>

make/migrations/postgresql/0030_1.11.0_schema.up.sql

@@ -3,19 +3,18 @@ CREATE TABLE artifact_2
 (
   id            SERIAL PRIMARY KEY NOT NULL,
   /* image, chart, etc */
-  type          varchar(255),
+  type          varchar(255) NOT NULL,
-  media_type    varchar(255),
+  media_type    varchar(255) NOT NULL,
+  /* the media type of some classical image manifest can be null, so don't add the "NOT NULL" constraint*/
   manifest_media_type varchar(255),
   project_id    int NOT NULL,
   repository_id int NOT NULL,
   digest        varchar(255) NOT NULL,
   size          bigint,  
   push_time     timestamp default CURRENT_TIMESTAMP,
-  platform      varchar(255),
+  pull_time     timestamp,
   extra_attrs   text,
   annotations   jsonb,
-  /* when updating the data the revision MUST be checked and updated */
-  revision      varchar(64) NOT NULL,
   CONSTRAINT unique_artifact_2 UNIQUE (repository_id, digest)
 );
 
@@ -24,11 +23,9 @@ CREATE TABLE tag
   id            SERIAL PRIMARY KEY NOT NULL,
   repository_id int NOT NULL,
   artifact_id   int NOT NULL,
-  name          varchar(255),
+  name          varchar(255) NOT NULL,
   push_time     timestamp default CURRENT_TIMESTAMP,
   pull_time     timestamp,
-  /* when updating the data the revision MUST be checked and updated */
-  revision      varchar(64) NOT NULL,
   CONSTRAINT unique_tag UNIQUE (repository_id, name)
 );
 
@@ -38,5 +35,6 @@ CREATE TABLE artifact_reference
   id          SERIAL PRIMARY KEY NOT NULL,
   parent_id   int NOT NULL,
   child_id    int NOT NULL,
+  platform    varchar(255),
   CONSTRAINT  unique_reference UNIQUE (parent_id, child_id)
 );

src/api/artifact/controller.go

@@ -0,0 +1,63 @@
+// Copyright Project Harbor 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 artifact
+
+import (
+	"context"
+	"github.com/goharbor/harbor/src/common/models"
+	"github.com/goharbor/harbor/src/pkg/q"
+	"time"
+)
+
+var (
+	// Ctl is a global artifact controller instance
+	Ctl = NewController()
+)
+
+// Controller defines the operations related with artifacts and tags
+type Controller interface {
+	// Ensure the artifact specified by the digest exists under the repository,
+	// creates it if it doesn't exist. If tags are provided, ensure they exist
+	// and are attached to the artifact. If the tags don't exist, create them first
+	Ensure(ctx context.Context, repository *models.RepoRecord, digest string, tags ...string) (err error)
+	// List artifacts according to the query and option
+	List(ctx context.Context, query *q.Query, option *Option) (total int64, artifacts []*Artifact, err error)
+	// Get the artifact specified by ID
+	Get(ctx context.Context, id int64, option *Option) (artifact *Artifact, err error)
+	// Delete the artifact specified by ID
+	Delete(ctx context.Context, id int64) (err error)
+	// DeleteTag deletes the tag specified by ID
+	DeleteTag(ctx context.Context, id int64) (err error)
+	// UpdatePullTime updates the pull time for the artifact. If the tag is provides, update the pull
+	// time of the tag as well
+	UpdatePullTime(ctx context.Context, artifactID int64, tag string, time time.Time) (err error)
+	// GetSubResource returns the sub resource of the artifact
+	// The sub resource is different according to the artifact type:
+	// build history for image; values.yaml, readme and dependencies for chart, etc
+	GetSubResource(ctx context.Context, artifactID int64, resource string) (*Resource, error)
+	// TODO move this to GC controller?
+	// Prune removes the useless artifact records. The underlying registry data will
+	// be removed during garbage collection
+	// Prune(ctx context.Context, option *Option) error
+}
+
+// NewController creates an instance of the default artifact controller
+func NewController() Controller {
+	// TODO implement
+	return nil
+}
+
+// As a redis lock is applied during the artifact pushing, we do not to handle the concurrent issues
+// for artifacts and tags

src/api/artifact/model.go

@@ -0,0 +1,55 @@
+// Copyright Project Harbor 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 artifact
+
+import (
+	"github.com/goharbor/harbor/src/pkg/artifact"
+	"github.com/goharbor/harbor/src/pkg/tag/model/tag"
+)
+
+// Artifact is the overall view of artifact
+// TODO reuse the model generated by swagger
+type Artifact struct {
+	artifact.Artifact
+	Tags             []*tag.Tag                 // the list of tags that attached to the artifact
+	SubResourceLinks map[string][]*ResourceLink // the resource link for build history(image), values.yaml(chart), dependency(chart), etc
+	// TODO add other attrs: signature, scan result, label, etc
+}
+
+// Resource defines the specific resource of different artifacts: build history for image, values.yaml for chart, etc
+type Resource struct {
+	Content     []byte // the content of the resource
+	ContentType string // the content type of the resource, returned as "Content-Type" header in API
+}
+
+// ResourceLink is a link via that a resource can be fetched
+type ResourceLink struct {
+	HREF     string
+	Absolute bool // specify the href is an absolute URL or not
+}
+
+// Option is used to specify the properties returned when listing/getting artifacts
+type Option struct {
+	WithTag        bool
+	WithLabel      bool
+	WithScanResult bool
+	WithSignature  bool
+}
+
+// TODO move this to GC controller?
+// Option for pruning artifact records
+// type Option struct {
+//	 KeepUntagged bool // keep the untagged artifacts or not
+// }

src/pkg/artifact/dao/model.go

@@ -22,7 +22,6 @@ import (
 
 func init() {
 	orm.RegisterModel(&Artifact{})
-	orm.RegisterModel(&Tag{})
 	orm.RegisterModel(&ArtifactReference{})
 }
 
@@ -37,10 +36,9 @@ type Artifact struct {
 	Digest            string    `orm:"column(digest)"`
 	Size              int64     `orm:"column(size)"`
 	PushTime          time.Time `orm:"column(push_time)"`
-	Platform          string    `orm:"column(platform)"`                // json string
+	PullTime          time.Time `orm:"column(pull_time)"`
 	ExtraAttrs        string    `orm:"column(extra_attrs)"`             // json string
 	Annotations       string    `orm:"column(annotations);type(jsonb)"` // json string
-	Revision          string    `orm:"column(revision)"`                // record data revision, when updating the data the revision MUST be checked and updated
 }
 
 // TableName for artifact
@@ -49,27 +47,12 @@ func (a *Artifact) TableName() string {
 	return "artifact_2"
 }
 
-// Tag model in database
-type Tag struct {
-	ID           int64     `orm:"pk;auto;column(id)"`
-	RepositoryID int64     `orm:"column(repository_id)"` // tags are the resources of repository, one repository only contains one same name tag
-	ArtifactID   int64     `orm:"column(artifact_id)"`   // the artifact ID that the tag attaches to, it changes when pushing a same name but different digest artifact
-	Name         string    `orm:"column(name)"`
-	PushTime     time.Time `orm:"column(push_time)"`
-	PullTime     time.Time `orm:"column(pull_time)"`
-	Revision     string    `orm:"column(revision)"` // record data revision, when updating the data the revision MUST be checked and updated
-}
-
-// TableName for tag
-func (t *Tag) TableName() string {
-	return "tag"
-}
-
 // ArtifactReference records the child artifact referenced by parent artifact
 type ArtifactReference struct {
 	ID       int64  `orm:"pk;auto;column(id)"`
 	ParentID int64  `orm:"column(parent_id)"`
 	ChildID  int64  `orm:"column(child_id)"`
+	Platform string `orm:"column(platform)"` // json string
 }
 
 // TableName for artifact reference

src/pkg/artifact/manager.go

@@ -0,0 +1,73 @@
+// Copyright Project Harbor 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 artifact
+
+import (
+	"context"
+	"github.com/goharbor/harbor/src/pkg/q"
+	"time"
+)
+
+var (
+	// Mgr is a global artifact manager instance
+	Mgr = NewManager()
+)
+
+// Manager is the only interface of artifact module to provide the management functions for artifacts
+type Manager interface {
+	// List artifacts according to the query, returns all artifacts if query is nil
+	List(ctx context.Context, query *q.Query) (total int64, artifacts []*Artifact, err error)
+	// Get the artifact specified by the ID
+	Get(ctx context.Context, id int64) (*Artifact, error)
+	// Create the artifact. If the artifact is an index, make sure all the artifacts it references
+	// already exist
+	Create(ctx context.Context, artifact *Artifact) (id int64, err error)
+	// Delete just deletes the artifact record. The underlying data of registry will be
+	// removed during garbage collection
+	Delete(ctx context.Context, id int64) error
+	// UpdatePullTime updates the pull time of the artifact
+	UpdatePullTime(ctx context.Context, artifactID int64, time time.Time) error
+}
+
+// NewManager returns an instance of the default manager
+func NewManager() Manager {
+	return &manager{}
+}
+
+var _ Manager = &manager{}
+
+type manager struct {
+}
+
+func (m *manager) List(ctx context.Context, query *q.Query) (total int64, artifacts []*Artifact, err error) {
+	// TODO implement
+	return 0, nil, nil
+}
+func (m *manager) Get(ctx context.Context, id int64) (*Artifact, error) {
+	// TODO implement
+	return nil, nil
+}
+func (m *manager) Create(ctx context.Context, artifact *Artifact) (id int64, err error) {
+	// TODO implement
+	return 0, nil
+}
+func (m *manager) Delete(ctx context.Context, id int64) error {
+	// TODO implement
+	return nil
+}
+func (m *manager) UpdatePullTime(ctx context.Context, artifactID int64, time time.Time) error {
+	// TODO implement
+	return nil
+}

src/pkg/artifact/manager_test.go

@@ -13,3 +13,5 @@
 // limitations under the License.
 
 package artifact
+
+// TODO add test cases after implementing the manager

src/pkg/artifact/model.go

@@ -12,15 +12,14 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package model
+package artifact
 
 import (
 	"encoding/json"
 	"time"
 
-	"github.com/goharbor/harbor/src/common/models"
 	"github.com/goharbor/harbor/src/common/utils/log"
-	"github.com/goharbor/harbor/src/pkg/artifact/manager/dao"
+	"github.com/goharbor/harbor/src/pkg/artifact/dao"
 	v1 "github.com/opencontainers/image-spec/specs-go/v1"
 )
 
@@ -32,22 +31,15 @@ type Artifact struct {
 	Type              string // image, chart, etc
 	MediaType         string // the media type of artifact. Mostly, it's the value of `manifest.config.mediatype`
 	ManifestMediaType string // the media type of manifest/index
-	Repository        *models.RepoRecord
+	ProjectID         int64
-	Tags              []*Tag // the list of tags that attached to the artifact
+	RepositoryID      int64
 	Digest            string
 	Size              int64
 	PushTime          time.Time
-	Platform          *v1.Platform               // when the parent of the artifact is an index, populate the platform information here
+	PullTime          time.Time
 	ExtraAttrs        map[string]interface{} // only contains the simple attributes specific for the different artifact type, most of them should come from the config layer
-	SubResourceLinks  map[string][]*ResourceLink // the resource link for build history(image), values.yaml(chart), dependency(chart), etc
 	Annotations       map[string]string
-	References        []int64 // child artifacts referenced by the parent artifact if the artifact is an index
+	References        []*Reference // child artifacts referenced by the parent artifact if the artifact is an index
-	Revision          string  // record data revision
-	// TODO: As the labels and signature aren't handled inside the artifact module,
-	// we should move it to the API level artifact model rather than
-	// keeping it here. The same to scan information
-	// Labels                  []*models.Label
-	// Signature               *Signature                 // add the signature in the artifact level rather than tag level as we cannot make sure the signature always apply to tag
 }
 
 // From converts the database level artifact to the business level object
@@ -56,21 +48,14 @@ func (a *Artifact) From(art *dao.Artifact) {
 	a.Type = art.Type
 	a.MediaType = art.MediaType
 	a.ManifestMediaType = art.ManifestMediaType
-	a.Repository = &models.RepoRecord{
+	a.ProjectID = art.ProjectID
-		ProjectID:    art.ProjectID,
+	a.RepositoryID = art.RepositoryID
-		RepositoryID: art.RepositoryID,
-	}
 	a.Digest = art.Digest
 	a.Size = art.Size
 	a.PushTime = art.PushTime
+	a.PullTime = art.PullTime
 	a.ExtraAttrs = map[string]interface{}{}
 	a.Annotations = map[string]string{}
-	a.Revision = art.Revision
-	if len(art.Platform) > 0 {
-		if err := json.Unmarshal([]byte(art.Platform), &a.Platform); err != nil {
-			log.Errorf("failed to unmarshal the platform of artifact %d: %v", art.ID, err)
-		}
-	}
 	if len(art.ExtraAttrs) > 0 {
 		if err := json.Unmarshal([]byte(art.ExtraAttrs), &a.ExtraAttrs); err != nil {
 			log.Errorf("failed to unmarshal the extra attrs of artifact %d: %v", art.ID, err)
@@ -90,20 +75,12 @@ func (a *Artifact) To() *dao.Artifact {
 		Type:              a.Type,
 		MediaType:         a.MediaType,
 		ManifestMediaType: a.ManifestMediaType,
-		ProjectID:         a.Repository.ProjectID,
+		ProjectID:         a.ProjectID,
-		RepositoryID:      a.Repository.RepositoryID,
+		RepositoryID:      a.RepositoryID,
 		Digest:            a.Digest,
 		Size:              a.Size,
 		PushTime:          a.PushTime,
-		Revision:          a.Revision,
+		PullTime:          a.PullTime,
-	}
-
-	if a.Platform != nil {
-		platform, err := json.Marshal(a.Platform)
-		if err != nil {
-			log.Errorf("failed to marshal the platform of artifact %d: %v", a.ID, err)
-		}
-		art.Platform = string(platform)
 	}
 	if len(a.ExtraAttrs) > 0 {
 		attrs, err := json.Marshal(a.ExtraAttrs)
@@ -122,44 +99,36 @@ func (a *Artifact) To() *dao.Artifact {
 	return art
 }
 
-// ResourceLink is a link via that a resource can be fetched
+// Reference records the child artifact referenced by parent artifact
-type ResourceLink struct {
+type Reference struct {
-	HREF     string
+	ParentID int64
-	Absolute bool // specify the href is an absolute URL or not
+	ChildID  int64
+	Platform *v1.Platform
 }
 
-// TODO: move it to the API level artifact model
+// From converts the data level reference to business level
-// Signature information
+func (r *Reference) From(ref *dao.ArtifactReference) {
-// type Signature struct {
+	r.ParentID = ref.ParentID
-// 	Signatures map[string]bool // tag: signed or not
+	r.ChildID = ref.ChildID
-// }
+	if len(ref.Platform) > 0 {
-
+		if err := json.Unmarshal([]byte(ref.Platform), r); err != nil {
-// Tag belongs to one repository and can only be attached to a single
+			log.Errorf("failed to unmarshal the platform of reference: %v", err)
-// one artifact under the repository
+		}
-type Tag struct {
+	}
-	ID       int64
-	Name     string
-	PushTime time.Time
-	PullTime time.Time
-	Revision string // record data revision
 }
 
-// From converts the database level tag to the business level object
+// To converts the reference to data level object
-func (t *Tag) From(tag *dao.Tag) {
+func (r *Reference) To() *dao.ArtifactReference {
-	t.ID = tag.ID
+	ref := &dao.ArtifactReference{
-	t.Name = tag.Name
+		ParentID: r.ParentID,
-	t.PushTime = tag.PushTime
+		ChildID:  r.ChildID,
-	t.PullTime = tag.PullTime
-	t.Revision = tag.Revision
 	}
-
+	if r.Platform != nil {
-// To converts the tag to the database level model
+		platform, err := json.Marshal(r.Platform)
-func (t *Tag) To() *dao.Tag {
+		if err != nil {
-	return &dao.Tag{
+			log.Errorf("failed to marshal the platform of reference: %v", err)
-		ID:       t.ID,
-		Name:     t.Name,
-		PushTime: t.PushTime,
-		PullTime: t.PullTime,
-		Revision: t.Revision,
 		}
+		ref.Platform = string(platform)
+	}
+	return ref
 }

src/pkg/artifact/model_test.go

@@ -12,15 +12,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package model
+package artifact
 
 import (
 	"testing"
 	"time"
 
-	"github.com/goharbor/harbor/src/common/models"
+	"github.com/goharbor/harbor/src/pkg/artifact/dao"
-	"github.com/goharbor/harbor/src/pkg/artifact/manager/dao"
-	v1 "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/suite"
 )
@@ -41,10 +39,9 @@ func (m *modelTestSuite) TestArtifactFrom() {
 		Digest:            "sha256:418fb88ec412e340cdbef913b8ca1bbe8f9e8dc705f9617414c1f2c8db980180",
 		Size:              1024,
 		PushTime:          time.Now(),
-		Platform:          `{"architecture":"amd64"}`,
+		PullTime:          time.Now(),
 		ExtraAttrs:        `{"attr1":"value1"}`,
 		Annotations:       `{"anno1":"value1"}`,
-		Revision:          "1",
 	}
 	art := &Artifact{}
 	art.From(dbArt)
@@ -52,15 +49,14 @@ func (m *modelTestSuite) TestArtifactFrom() {
 	assert.Equal(t, dbArt.Type, art.Type)
 	assert.Equal(t, dbArt.MediaType, art.MediaType)
 	assert.Equal(t, dbArt.ManifestMediaType, art.ManifestMediaType)
-	assert.Equal(t, dbArt.ProjectID, art.Repository.ProjectID)
+	assert.Equal(t, dbArt.ProjectID, art.ProjectID)
-	assert.Equal(t, dbArt.RepositoryID, art.Repository.RepositoryID)
+	assert.Equal(t, dbArt.RepositoryID, art.RepositoryID)
 	assert.Equal(t, dbArt.Digest, art.Digest)
 	assert.Equal(t, dbArt.Size, art.Size)
 	assert.Equal(t, dbArt.PushTime, art.PushTime)
-	assert.Equal(t, "amd64", art.Platform.Architecture)
+	assert.Equal(t, dbArt.PullTime, art.PullTime)
 	assert.Equal(t, "value1", art.ExtraAttrs["attr1"].(string))
 	assert.Equal(t, "value1", art.Annotations["anno1"])
-	assert.Equal(t, dbArt.Revision, art.Revision)
 }
 
 func (m *modelTestSuite) TestArtifactTo() {
@@ -68,75 +64,34 @@ func (m *modelTestSuite) TestArtifactTo() {
 	art := &Artifact{
 		ID:                1,
 		Type:              "IMAGE",
-		Repository: &models.RepoRecord{
 		ProjectID:         1,
 		RepositoryID:      1,
-		},
 		MediaType:         "application/vnd.oci.image.config.v1+json",
 		ManifestMediaType: "application/vnd.oci.image.manifest.v1+json",
 		Digest:            "sha256:418fb88ec412e340cdbef913b8ca1bbe8f9e8dc705f9617414c1f2c8db980180",
 		Size:              1024,
 		PushTime:          time.Now(),
-		Platform: &v1.Platform{
+		PullTime:          time.Now(),
-			Architecture: "amd64",
-		},
 		ExtraAttrs: map[string]interface{}{
 			"attr1": "value1",
 		},
 		Annotations: map[string]string{
 			"anno1": "value1",
 		},
-		Revision: "1",
 	}
 	dbArt := art.To()
 	assert.Equal(t, art.ID, dbArt.ID)
 	assert.Equal(t, art.Type, dbArt.Type)
 	assert.Equal(t, art.MediaType, dbArt.MediaType)
 	assert.Equal(t, art.ManifestMediaType, dbArt.ManifestMediaType)
-	assert.Equal(t, art.Repository.ProjectID, dbArt.ProjectID)
+	assert.Equal(t, art.ProjectID, dbArt.ProjectID)
-	assert.Equal(t, art.Repository.RepositoryID, dbArt.RepositoryID)
+	assert.Equal(t, art.RepositoryID, dbArt.RepositoryID)
 	assert.Equal(t, art.Digest, dbArt.Digest)
 	assert.Equal(t, art.Size, dbArt.Size)
 	assert.Equal(t, art.PushTime, dbArt.PushTime)
-	assert.Equal(t, `{"architecture":"amd64","os":""}`, dbArt.Platform)
+	assert.Equal(t, art.PullTime, dbArt.PullTime)
 	assert.Equal(t, `{"attr1":"value1"}`, dbArt.ExtraAttrs)
 	assert.Equal(t, `{"anno1":"value1"}`, dbArt.Annotations)
-	assert.Equal(t, art.Revision, dbArt.Revision)
-}
-
-func (m *modelTestSuite) TestTagFrom() {
-	t := m.T()
-	dbTag := &dao.Tag{
-		ID:       1,
-		Name:     "1.0",
-		PushTime: time.Now(),
-		PullTime: time.Now(),
-		Revision: "1",
-	}
-	tag := &Tag{}
-	tag.From(dbTag)
-	assert.Equal(t, dbTag.ID, tag.ID)
-	assert.Equal(t, dbTag.Name, tag.Name)
-	assert.Equal(t, dbTag.PushTime, tag.PushTime)
-	assert.Equal(t, dbTag.PullTime, tag.PullTime)
-	assert.Equal(t, dbTag.Revision, tag.Revision)
-}
-
-func (m *modelTestSuite) TestTagTo() {
-	t := m.T()
-	tag := &Tag{
-		ID:       1,
-		Name:     "1.0",
-		PushTime: time.Now(),
-		PullTime: time.Now(),
-		Revision: "1",
-	}
-	dbTag := tag.To()
-	assert.Equal(t, tag.ID, dbTag.ID)
-	assert.Equal(t, tag.Name, dbTag.Name)
-	assert.Equal(t, tag.PushTime, dbTag.PushTime)
-	assert.Equal(t, tag.PullTime, dbTag.PullTime)
-	assert.Equal(t, tag.Revision, dbTag.Revision)
 }
 
 func TestModel(t *testing.T) {

src/pkg/tag/dao/dao.go

@@ -12,4 +12,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package manager
+package dao
+
+import (
+	"github.com/astaxie/beego/orm"
+	"github.com/goharbor/harbor/src/pkg/tag/model/tag"
+)
+
+func init() {
+	orm.RegisterModel(&tag.Tag{})
+}

src/pkg/tag/manager.go

@@ -0,0 +1,46 @@
+// Copyright Project Harbor 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 tag
+
+import (
+	"context"
+	"github.com/goharbor/harbor/src/pkg/q"
+	"github.com/goharbor/harbor/src/pkg/tag/model/tag"
+)
+
+var (
+	// Mgr is a global instance of tag manager
+	Mgr = NewManager()
+)
+
+// Manager manages the tags
+type Manager interface {
+	// List tags according to the query
+	List(ctx context.Context, query *q.Query) (total int64, tags []*tag.Tag, err error)
+	// Get the tag specified by ID
+	Get(ctx context.Context, id int64) (tag *tag.Tag, err error)
+	// Create the tag and returns the ID
+	Create(ctx context.Context, tag *tag.Tag) (id int64, err error)
+	// Update the tag
+	Update(ctx context.Context, tag *tag.Tag) (err error)
+	// Delete the tag specified by ID
+	Delete(ctx context.Context, id int64) (err error)
+}
+
+// NewManager creates an instance of the default tag manager
+func NewManager() Manager {
+	// TODO implement
+	return nil
+}

src/pkg/tag/model/tag/model.go

@@ -0,0 +1,29 @@
+// Copyright Project Harbor 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 tag
+
+import (
+	"time"
+)
+
+// Tag model in database
+type Tag struct {
+	ID           int64     `orm:"pk;auto;column(id)"`
+	RepositoryID int64     `orm:"column(repository_id)"` // tags are the resources of repository, one repository only contains one same name tag
+	ArtifactID   int64     `orm:"column(artifact_id)"`   // the artifact ID that the tag attaches to, it changes when pushing a same name but different digest artifact
+	Name         string    `orm:"column(name)"`
+	PushTime     time.Time `orm:"column(push_time)"`
+	PullTime     time.Time `orm:"column(pull_time)"`
+}