Support for deleting Snapshot (#39)

* Deleting snapshot by ID

* Work in progress

* Unit test

* fix comments

api/handlers_snapshots.go

@@ -159,3 +159,36 @@ func (s *server) SnapshotCreateHandler(w http.ResponseWriter, r *http.Request) {
 
 	handleResponseOk(w, out)
 }
+
+func (s *server) SnapshotDeleteHandler(w http.ResponseWriter, r *http.Request) {
+	w = LogWriter{w}
+	vars := mux.Vars(r)
+	account := s.mapAccountNumber(vars["account"])
+	id := vars["id"]
+
+	policy, err := generatePolicy([]string{"ec2:DeleteSnapshot"})
+	if err != nil {
+		handleError(w, err)
+		return
+	}
+
+	orch, err := s.newEc2Orchestrator(r.Context(), &sessionParams{
+		role:         fmt.Sprintf("arn:aws:iam::%s:role/%s", account, s.session.RoleName),
+		inlinePolicy: policy,
+		policyArns: []string{
+			"arn:aws:iam::aws:policy/AmazonEC2ReadOnlyAccess",
+		},
+	})
+	if err != nil {
+		handleError(w, err)
+		return
+	}
+
+	err = orch.deleteSnapshot(r.Context(), id)
+	if err != nil {
+		handleError(w, err)
+		return
+	}
+
+	handleResponseOk(w, nil)
+}

api/orchestration_snapshot.go

@@ -44,3 +44,20 @@ func (o *ec2Orchestrator) createSnapshot(ctx context.Context, req *Ec2SnapshotCr
 
 	return snapshotId, nil
 }
+
+func (o *ec2Orchestrator) deleteSnapshot(ctx context.Context, id string) error {
+	if id == "" {
+		return apierror.New(apierror.ErrBadRequest, "invalid input", nil)
+	}
+	log.Debugf("got request to delete snapshot %s", id)
+
+	input := &ec2.DeleteSnapshotInput{
+		SnapshotId: aws.String(id),
+	}
+
+	if err := o.ec2Client.DeleteSnapshot(ctx, input); err != nil {
+		return err
+	}
+
+	return nil
+}

api/routes.go

@@ -81,6 +81,6 @@ func (s *server) routes() {
 	api.HandleFunc("/{account}/instanceprofiles/{name}", s.ProxyRequestHandler).Methods(http.MethodDelete)
 	api.HandleFunc("/{account}/sgs/{id}", s.SecurityGroupDeleteHandler).Methods(http.MethodDelete)
 	api.HandleFunc("/{account}/volumes/{id}", s.VolumeDeleteHandler).Methods(http.MethodDelete)
-	api.HandleFunc("/{account}/snapshots/{id}", s.ProxyRequestHandler).Methods(http.MethodDelete)
+	api.HandleFunc("/{account}/snapshots/{id}", s.SnapshotDeleteHandler).Methods(http.MethodDelete)
 	api.HandleFunc("/{account}/images/{id}", s.ProxyRequestHandler).Methods(http.MethodDelete)
 }

ec2/snapshots.go

@@ -88,3 +88,17 @@ func (e *Ec2) CreateSnapshot(ctx context.Context, input *ec2.CreateSnapshotInput
 
 	return aws.StringValue(out.SnapshotId), nil
 }
+
+func (e *Ec2) DeleteSnapshot(ctx context.Context, input *ec2.DeleteSnapshotInput) error {
+	if input == nil {
+		return apierror.New(apierror.ErrBadRequest, "invalid input", nil)
+	}
+
+	log.Infof("deleting snapshot %s", *input.SnapshotId)
+
+	_, err := e.Service.DeleteSnapshotWithContext(ctx, input)
+	if err != nil {
+		return common.ErrCode("failed to delete snapshot", err)
+	}
+	return nil
+}

ec2/snapshots_test.go

@@ -17,6 +17,14 @@ func (m mockEC2Client) CreateSnapshotWithContext(ctx aws.Context, input *ec2.Cre
 	}
 	return &ec2.Snapshot{SnapshotId: aws.String("1234")}, nil
 }
+
+func (m mockEC2Client) DeleteSnapshotWithContext(aws.Context, *ec2.DeleteSnapshotInput, ...request.Option) (*ec2.DeleteSnapshotOutput, error) {
+	if m.err != nil {
+		return nil, m.err
+	}
+	return &ec2.DeleteSnapshotOutput{}, nil
+}
+
 func TestEc2_CreateSnapshot(t *testing.T) {
 	type fields struct {
 		Service ec2iface.EC2API
@@ -69,3 +77,50 @@ func TestEc2_CreateSnapshot(t *testing.T) {
 		})
 	}
 }
+
+func TestEc2_DeleteSnapshot(t *testing.T) {
+	type fields struct {
+		Service ec2iface.EC2API
+	}
+	type args struct {
+		ctx   context.Context
+		input *ec2.DeleteSnapshotInput
+	}
+	tests := []struct {
+		name    string
+		fields  fields
+		e       *Ec2
+		args    args
+		wantErr bool
+	}{
+		{
+			name: "success case",
+			args: args{ctx: context.TODO(), input: &ec2.DeleteSnapshotInput{
+				SnapshotId: aws.String("3514")}},
+			fields:  fields{Service: newmockEC2Client(t, nil)},
+			wantErr: false,
+		},
+		{
+			name:    "aws error",
+			args:    args{ctx: context.TODO(), input: &ec2.DeleteSnapshotInput{SnapshotId: aws.String("1234")}},
+			fields:  fields{Service: newmockEC2Client(t, awserr.New("Bad Request", "boom.", nil))},
+			wantErr: true,
+		},
+		{
+			name:    "nil input",
+			args:    args{ctx: context.TODO()},
+			fields:  fields{Service: newmockEC2Client(t, nil)},
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			e := &Ec2{
+				Service: tt.fields.Service,
+			}
+			if err := e.DeleteSnapshot(tt.args.ctx, tt.args.input); (err != nil) != tt.wantErr {
+				t.Errorf("Ec2.DeleteSnapshot() error = %v, wantErr %v", err, tt.wantErr)
+			}
+		})
+	}
+}