Eggjs -typeorm treeenity practice

Tree - Entitiy

Tutorial address

https://typeorm.io/#/tree-entities

Case study

scene ： Grouping design 、 Tree design 、 Menu design

Tree structure , In parentheses is stored ID

-  The north China (11) 
    -  Henan (14)
        -  zhengzhou (17)
        -  Jiaozuo (18)
    -  hebei (15)
        -  taiyuan (19)
-  south China (12)
-  southwest (13)
    -  sichuan (16)

UserGroup

@Entity()
@Tree("closure-table")
export class UserGroup {
  @PrimaryGeneratedColumn()
    id: number;

    @Column({ default: 0 })
    status: number;

    @CreateDateColumn()
    createDate: Date;

    @UpdateDateColumn()
    updateDate: Date;
    
    @Column()
    groupName: string;

    @TreeChildren()
    children: UserGroup[];

    @TreeParent()
    parent: UserGroup;
}

UserGroupRepository

@EntityRepository(UserGroup)
export default class UserGroupRepository extends TreeRepository<UserGroup> {
}

1. Add a level one node

Code

const userGroup = new UserGroup()
userGroup.groupName = ' The north China '
const saveResult = await userGroupRep.save(userGroup)

data

{
        "groupName": " The north China ",
        "id": 11,
        "status": 0,
        "createDate": "2019-04-20T02:44:48.799Z",
        "updateDate": "2019-04-20T02:44:48.799Z"
 }

2. Add child nodes

add to sichuan

Code

const userGroupChild = new UserGroup()
userGroupChild.groupName = ' sichuan '
const parent = await userGroupRep.findOne(13);
if(parent){
     userGroupChild.parent = parent
 }
await userGroupRep.save(userGroupChild)

The data format is consistent with the above

{
    "code": 0,
    "msg": "ok",
    "data": [
        {
            "id": 11,
            "status": 0,
            "createDate": "2019-04-20T02:44:48.799Z",
            "updateDate": "2019-04-20T02:44:48.799Z",
            "groupName": " The north China ",
            "children": [
                {
                    "id": 14,
                    "status": 0,
                    "createDate": "2019-04-20T03:02:58.551Z",
                    "updateDate": "2019-04-20T03:02:58.551Z",
                    "groupName": " Henan ",
                    "children": [
                        {
                            "id": 17,
                            "status": 0,
                            "createDate": "2019-04-20T03:08:24.459Z",
                            "updateDate": "2019-04-20T03:08:24.459Z",
                            "groupName": " zhengzhou ",
                            "children": []
                        },
                        {
                            "id": 18,
                            "status": 0,
                            "createDate": "2019-04-20T03:08:39.077Z",
                            "updateDate": "2019-04-20T03:08:39.077Z",
                            "groupName": " Jiaozuo ",
                            "children": []
                        }
                    ]
                },
                {
                    "id": 15,
                    "status": 0,
                    "createDate": "2019-04-20T03:04:28.248Z",
                    "updateDate": "2019-04-20T03:04:28.248Z",
                    "groupName": " hebei ",
                    "children": []
                }
            ]
        },
        {
            "id": 12,
            "status": 0,
            "createDate": "2019-04-20T02:58:51.236Z",
            "updateDate": "2019-04-20T02:58:51.236Z",
            "groupName": " south China ",
            "children": []
        },
        {
            "id": 13,
            "status": 0,
            "createDate": "2019-04-20T02:59:07.329Z",
            "updateDate": "2019-04-20T02:59:07.329Z",
            "groupName": " southwest ",
            "children": [
                {
                    "id": 16,
                    "status": 0,
                    "createDate": "2019-04-20T03:05:34.187Z",
                    "updateDate": "2019-04-20T03:05:34.187Z",
                    "groupName": " sichuan ",
                    "children": []
                }
            ]
        }
    ]
}

3. All data is displayed nested

Code

await userGroupRep.findTrees()

data

{
    "code": 0,
    "msg": "ok",
    "data": [
        {
            "id": 11,
            "status": 0,
            "createDate": "2019-04-20T02:44:48.799Z",
            "updateDate": "2019-04-20T02:44:48.799Z",
            "groupName": " The north China ",
            "children": [
                {
                    "id": 14,
                    "status": 0,
                    "createDate": "2019-04-20T03:02:58.551Z",
                    "updateDate": "2019-04-20T03:02:58.551Z",
                    "groupName": " Henan ",
                    "children": [
                        {
                            "id": 17,
                            "status": 0,
                            "createDate": "2019-04-20T03:08:24.459Z",
                            "updateDate": "2019-04-20T03:08:24.459Z",
                            "groupName": " zhengzhou ",
                            "children": []
                        },
                        {
                            "id": 18,
                            "status": 0,
                            "createDate": "2019-04-20T03:08:39.077Z",
                            "updateDate": "2019-04-20T03:08:39.077Z",
                            "groupName": " Jiaozuo ",
                            "children": []
                        }
                    ]
                },
                {
                    "id": 15,
                    "status": 0,
                    "createDate": "2019-04-20T03:04:28.248Z",
                    "updateDate": "2019-04-20T03:04:28.248Z",
                    "groupName": " hebei ",
                    "children": []
                }
            ]
        },
        {
            "id": 12,
            "status": 0,
            "createDate": "2019-04-20T02:58:51.236Z",
            "updateDate": "2019-04-20T02:58:51.236Z",
            "groupName": " south China ",
            "children": []
        },
        {
            "id": 13,
            "status": 0,
            "createDate": "2019-04-20T02:59:07.329Z",
            "updateDate": "2019-04-20T02:59:07.329Z",
            "groupName": " southwest ",
            "children": [
                {
                    "id": 16,
                    "status": 0,
                    "createDate": "2019-04-20T03:05:34.187Z",
                    "updateDate": "2019-04-20T03:05:34.187Z",
                    "groupName": " sichuan ",
                    "children": []
                }
            ]
        }
    ]
}

4. Show only the root directory

Code

await userGroupRep.findRoots()

data

{
    "code": 0,
    "msg": "ok",
    "data": [
        {
            "id": 11,
            "status": 0,
            "createDate": "2019-04-20T02:44:48.799Z",
            "updateDate": "2019-04-20T02:44:48.799Z",
            "groupName": " The north China "
        },
        {
            "id": 12,
            "status": 0,
            "createDate": "2019-04-20T02:58:51.236Z",
            "updateDate": "2019-04-20T02:58:51.236Z",
            "groupName": " south China "
        },
        {
            "id": 13,
            "status": 0,
            "createDate": "2019-04-20T02:59:07.329Z",
            "updateDate": "2019-04-20T02:59:07.329Z",
            "groupName": " southwest "
        }
    ]
}

5. Appoint Parent All child nodes of （ No nesting ）

Code

 const groups = await userGroupRep.findDescendants(parent);

data

{
    "code": 0,
    "msg": "ok",
    "data": [
        {
            "id": 11,
            "status": 0,
            "createDate": "2019-04-20T02:44:48.799Z",
            "updateDate": "2019-04-20T02:44:48.799Z",
            "groupName": " The north China "
        },
        {
            "id": 14,
            "status": 0,
            "createDate": "2019-04-20T03:02:58.551Z",
            "updateDate": "2019-04-20T03:02:58.551Z",
            "groupName": " Henan "
        },
        {
            "id": 15,
            "status": 0,
            "createDate": "2019-04-20T03:04:28.248Z",
            "updateDate": "2019-04-20T03:04:28.248Z",
            "groupName": " hebei "
        },
        {
            "id": 17,
            "status": 0,
            "createDate": "2019-04-20T03:08:24.459Z",
            "updateDate": "2019-04-20T03:08:24.459Z",
            "groupName": " zhengzhou "
        },
        {
            "id": 18,
            "status": 0,
            "createDate": "2019-04-20T03:08:39.077Z",
            "updateDate": "2019-04-20T03:08:39.077Z",
            "groupName": " Jiaozuo "
        }
    ]
}

6. Appoint Parent All child nodes of （ nesting ）

Code

await userGroupRep.findDescendantsTree(parent);

data

{
    "code": 0,
    "msg": "ok",
    "data": {
        "id": 11,
        "status": 0,
        "createDate": "2019-04-20T02:44:48.799Z",
        "updateDate": "2019-04-20T02:44:48.799Z",
        "groupName": " The north China ",
        "children": [
            {
                "id": 14,
                "status": 0,
                "createDate": "2019-04-20T03:02:58.551Z",
                "updateDate": "2019-04-20T03:02:58.551Z",
                "groupName": " Henan ",
                "children": [
                    {
                        "id": 17,
                        "status": 0,
                        "createDate": "2019-04-20T03:08:24.459Z",
                        "updateDate": "2019-04-20T03:08:24.459Z",
                        "groupName": " zhengzhou ",
                        "children": []
                    },
                    {
                        "id": 18,
                        "status": 0,
                        "createDate": "2019-04-20T03:08:39.077Z",
                        "updateDate": "2019-04-20T03:08:39.077Z",
                        "groupName": " Jiaozuo ",
                        "children": []
                    }
                ]
            },
            {
                "id": 15,
                "status": 0,
                "createDate": "2019-04-20T03:04:28.248Z",
                "updateDate": "2019-04-20T03:04:28.248Z",
                "groupName": " hebei ",
                "children": []
            }
        ]
    }
}

7. Appoint Parent Number of child nodes of

Code

 const groups = await userGroupRep.countDescendants(parent);

data

{
    "code": 0,
    "msg": "ok",
    "data": 5
}

8. Appoint Parent Operations related to the parent node of

 No nested data ：userGroupRep.findAncestors() 
 Nested data ：userGroupRep.findAncestorsTree()
 Number of parent nodes ：userGroupRep.countAncestors()

9. Specify the operation related to each node condition

const childrens = await repository
    .createDescendantsQueryBuilder("category", "categoryClosure", parentCategory)
    .andWhere("category.type = 'secondary'")
    .getMany();