Add labels to tasks (#45)

pkg/models/label_task.go

@@ -0,0 +1,153 @@
+//  Vikunja is a todo-list application to facilitate your life.
+//  Copyright 2018 Vikunja and contributors. All rights reserved.
+//
+//  This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package models
+
+import (
+	"code.vikunja.io/web"
+	"github.com/go-xorm/builder"
+)
+
+// Delete deletes a label on a task
+// @Summary Remove a label from a task
+// @Description Remove a label from a task. The user needs to have write-access to the list to be able do this.
+// @tags labels
+// @Accept json
+// @Produce json
+// @Security ApiKeyAuth
+// @Param task path int true "Task ID"
+// @Param label path int true "Label ID"
+// @Success 200 {object} models.Label "The label was successfully removed."
+// @Failure 403 {object} code.vikunja.io/web.HTTPError "Not allowed to remove the label."
+// @Failure 404 {object} code.vikunja.io/web.HTTPError "Label not found."
+// @Failure 500 {object} models.Message "Internal error"
+// @Router /tasks/{task}/labels/{label} [delete]
+func (l *LabelTask) Delete() (err error) {
+	_, err = x.Delete(&LabelTask{LabelID: l.LabelID, TaskID: l.TaskID})
+	return err
+}
+
+// Create adds a label to a task
+// @Summary Add a label to a task
+// @Description Add a label to a task. The user needs to have write-access to the list to be able do this.
+// @tags labels
+// @Accept json
+// @Produce json
+// @Security ApiKeyAuth
+// @Param task path int true "Task ID"
+// @Param label body models.Label true "The label object"
+// @Success 200 {object} models.Label "The created label relation object."
+// @Failure 400 {object} code.vikunja.io/web.HTTPError "Invalid label object provided."
+// @Failure 403 {object} code.vikunja.io/web.HTTPError "Not allowed to add the label."
+// @Failure 404 {object} code.vikunja.io/web.HTTPError "The label does not exist."
+// @Failure 500 {object} models.Message "Internal error"
+// @Router /tasks/{task}/labels [put]
+func (l *LabelTask) Create(a web.Auth) (err error) {
+	// Check if the label is already added
+	exists, err := x.Exist(&LabelTask{LabelID: l.LabelID, TaskID: l.TaskID})
+	if err != nil {
+		return err
+	}
+	if exists {
+		return ErrLabelIsAlreadyOnTask{l.LabelID, l.TaskID}
+	}
+
+	// Insert it
+	_, err = x.Insert(l)
+	return err
+}
+
+// ReadAll gets all labels on a task
+// @Summary Get all labels on a task
+// @Description Returns all labels which are assicociated with a given task.
+// @tags labels
+// @Accept json
+// @Produce json
+// @Param task path int true "Task ID"
+// @Param p query int false "The page number. Used for pagination. If not provided, the first page of results is returned."
+// @Param s query string false "Search labels by label text."
+// @Security ApiKeyAuth
+// @Success 200 {array} models.Label "The labels"
+// @Failure 500 {object} models.Message "Internal error"
+// @Router /tasks/{task}/labels [get]
+func (l *LabelTask) ReadAll(search string, a web.Auth, page int) (labels interface{}, err error) {
+	u, err := getUserWithError(a)
+	if err != nil {
+		return nil, err
+	}
+
+	// Check if the user has the right to see the task
+	task, err := GetListTaskByID(l.TaskID)
+	if err != nil {
+		return nil, err
+	}
+
+	if !task.CanRead(a) {
+		return nil, ErrNoRightToSeeTask{l.TaskID, u.ID}
+	}
+
+	return getLabelsByTaskIDs(search, u, page, []int64{l.TaskID}, false)
+}
+
+type labelWithTaskID struct {
+	TaskID int64
+	Label  `xorm:"extends"`
+}
+
+// Helper function to get all labels for a set of tasks
+// Used when getting all labels for one task as well when getting all lables
+func getLabelsByTaskIDs(search string, u *User, page int, taskIDs []int64, getUnusedLabels bool) (ls []*labelWithTaskID, err error) {
+	// Incl unused labels
+	var uidOrNil interface{}
+	var requestOrNil interface{}
+	if getUnusedLabels {
+		uidOrNil = u.ID
+		requestOrNil = "label_task.label_id != null OR labels.created_by_id = ?"
+	}
+
+	// Get all labels associated with these labels
+	var labels []*labelWithTaskID
+	err = x.Table("labels").
+		Select("labels.*, label_task.task_id").
+		Join("LEFT", "label_task", "label_task.label_id = labels.id").
+		Where(requestOrNil, uidOrNil).
+		Or(builder.In("label_task.task_id", taskIDs)).
+		And("labels.title LIKE ?", "%"+search+"%").
+		GroupBy("labels.id").
+		Limit(getLimitFromPageIndex(page)).
+		Find(&labels)
+	if err != nil {
+		return nil, err
+	}
+
+	// Get all created by users
+	var userids []int64
+	for _, l := range labels {
+		userids = append(userids, l.CreatedByID)
+	}
+	users := make(map[int64]*User)
+	err = x.In("id", userids).Find(&users)
+	if err != nil {
+		return nil, err
+	}
+
+	// Put it all together
+	for in, l := range labels {
+		labels[in].CreatedBy = users[l.CreatedByID]
+	}
+
+	return labels, err
+}