content/en/docs/clients/restful-api/edge.md

title: “Edge API” linkTitle: “Edge” weight: 8

2.2 Edge

顶点 id 格式的修改也影响到了边的 Id 以及源顶点和目标顶点 id 的格式。

EdgeId是由 src-vertex-id + direction + label + sort-values + tgt-vertex-id 拼接而成，但是这里的顶点id类型不是通过引号区分的，而是根据前缀区分：

当 id 类型为 number 时，EdgeId 的顶点 id 前有一个前缀L ，形如 “L123456>1>>L987654”
当 id 类型为 string 时，EdgeId 的顶点 id 前有一个前缀S ，形如 “S1:peter>1>>S2:lop”

接下来的示例均假设已经创建好了前述的各种schema和vertex信息

2.2.1 创建一条边

Params说明

label：边类型名称，必填
outV：源顶点id，必填
inV：目标顶点id，必填
outVLabel：源顶点类型。必填
inVLabel：目标顶点类型。必填
properties: 边关联的属性，对象内部结构为：
1. name：属性名称
2. value：属性值

Method & Url

POST http://localhost:8080/graphs/hugegraph/graph/edges

Request Body

{
    "label": "created",
    "outV": "1:peter",
    "inV": "2:lop",
    "outVLabel": "person",
    "inVLabel": "software",
    "properties": {
        "date": "2017-5-18",
        "weight": 0.2
    }
}

Response Status

Response Body

{
    "id": "S1:peter>1>>S2:lop",
    "label": "created",
    "type": "edge",
    "inVLabel": "software",
    "outVLabel": "person",
    "inV": "2:lop",
    "outV": "1:peter",
    "properties": {
        "date": "2017-5-18",
        "weight": 0.2
    }
}

2.2.2 创建多条边

Params

check_vertex: 是否检查顶点存在(true | false)，当设置为 true 而待插入边的源顶点或目标顶点不存在时会报错。

Method & Url

POST http://localhost:8080/graphs/hugegraph/graph/edges/batch

Request Body

[
    {
        "label": "created",
        "outV": "1:peter",
        "inV": "2:lop",
        "outVLabel": "person",
        "inVLabel": "software",
        "properties": {
            "date": "2017-5-18",
            "weight": 0.2
        }
    },
    {
        "label": "knows",
        "outV": "1:marko",
        "inV": "1:vadas",
        "outVLabel": "person",
        "inVLabel": "person",
        "properties": {
            "date": "2016-01-10",
            "weight": 0.5
        }
    }
]

Response Status

Response Body

[
    "S1:peter>1>>S2:lop",
    "S1:marko>2>>S1:vadas"
]

2.2.3 更新边属性

Method & Url

PUT http://localhost:8080/graphs/hugegraph/graph/edges/S1:peter>1>>S2:lop?action=append

Request Body

{
    "properties": {
        "weight": 1.0
    }
}

注意：属性的取值是有三种类别的，分别是single、set和list。如果是single，表示增加或更新属性值；如果是set或list，则表示追加属性值。

Response Status

Response Body

{
    "id": "S1:peter>1>>S2:lop",
    "label": "created",
    "type": "edge",
    "inVLabel": "software",
    "outVLabel": "person",
    "inV": "2:lop",
    "outV": "1:peter",
    "properties": {
        "date": "2017-5-18",
        "weight": 1
    }
}

2.2.4 批量更新边属性

功能说明

与批量更新顶点属性类似

假设原边及属性为：

{
    "edges":[
        {
            "id":"S1:josh>2>>S2:ripple",
            "label":"created",
            "type":"edge",
            "outV":"1:josh",
            "outVLabel":"person",
            "inV":"2:ripple",
            "inVLabel":"software",
            "properties":{
                "weight":1,
                "date":1512835200000
            }
        },
        {
            "id":"S1:marko>1>7JooBil0>S1:josh",
            "label":"knows",
            "type":"edge",
            "outV":"1:marko",
            "outVLabel":"person",
            "inV":"1:josh",
            "inVLabel":"person",
            "properties":{
                "weight":1,
                "date":1361289600000
            }
        }
    ]
}

Method & Url

PUT http://127.0.0.1:8080/graphs/hugegraph/graph/edges/batch

Request Body

{
    "edges":[
        {
            "id":"S1:josh>2>>S2:ripple",
            "label":"created",
            "outV":"1:josh",
            "outVLabel":"person",
            "inV":"2:ripple",
            "inVLabel":"software",
            "properties":{
                "weight":0.1,
                "date":1522835200000
            }
        },
        {
            "id":"S1:marko>1>7JooBil0>S1:josh",
            "label":"knows",
            "outV":"1:marko",
            "outVLabel":"person",
            "inV":"1:josh",
            "inVLabel":"person",
            "properties":{
                "weight":0.2,
                "date":1301289600000
            }
        }
    ],
    "update_strategies":{
        "weight":"SUM",
        "date":"BIGGER"
    },
    "check_vertex": false,
    "create_if_not_exist":true
}

Response Status

Response Body

{
    "edges":[
        {
            "id":"S1:josh>2>>S2:ripple",
            "label":"created",
            "type":"edge",
            "outV":"1:josh",
            "outVLabel":"person",
            "inV":"2:ripple",
            "inVLabel":"software",
            "properties":{
                "weight":1.1,
                "date":1522835200000
            }
        },
        {
            "id":"S1:marko>1>7JooBil0>S1:josh",
            "label":"knows",
            "type":"edge",
            "outV":"1:marko",
            "outVLabel":"person",
            "inV":"1:josh",
            "inVLabel":"person",
            "properties":{
                "weight":1.2,
                "date":1301289600000
            }
        }
    ]
}

2.2.5 删除边属性

Method & Url

PUT http://localhost:8080/graphs/hugegraph/graph/edges/S1:peter>1>>S2:lop?action=eliminate

Request Body

{
    "properties": {
        "weight": 1.0
    }
}

注意：这里会直接删除属性（删除key和所有value），无论其属性的取值是single、set或list。

Response Status

Response Body

{
    "id": "S1:peter>1>>S2:lop",
    "label": "created",
    "type": "edge",
    "inVLabel": "software",
    "outVLabel": "person",
    "inV": "2:lop",
    "outV": "1:peter",
    "properties": {
        "date": "20170324"
    }
}

2.2.6 获取符合条件的边

Params

vertex_id: 顶点id
direction: 边的方向(OUT | IN | BOTH)
label: 边的标签
properties: 属性键值对(根据属性查询的前提是预先建立了索引)
offset：偏移，默认为0
limit: 查询数目，默认为100
page: 页号

支持的查询有以下几种：

提供vertex_id参数时，不可以使用参数page，direction、label、properties可选，offset和limit可以限制结果范围
不提供vertex_id参数时，label和properties可选
- 如果使用page参数，则：offset参数不可用（不填或者为0），direction不可用，properties最多只能有一个
- 如果不使用page参数，则：offset和limit可以用来限制结果范围，direction参数忽略

属性键值对由JSON格式的属性名称和属性值组成，允许多个属性键值对作为查询条件，属性值支持精确匹配和范围匹配，精确匹配时形如properties={"weight":0.8}，范围匹配时形如properties={"age":"P.gt(0.8)"},范围匹配支持的表达式如下：

表达式	说明
P.eq(number)	属性值等于number的边
P.neq(number)	属性值不等于number的边
P.lt(number)	属性值小于number的边
P.lte(number)	属性值小于等于number的边
P.gt(number)	属性值大于number的边
P.gte(number)	属性值大于等于number的边
P.between(number1,number2)	属性值大于等于number1且小于number2的边
P.inside(number1,number2)	属性值大于number1且小于number2的边
P.outside(number1,number2)	属性值小于number1且大于number2的边
P.within(value1,value2,value3,...)	属性值等于任何一个给定value的边

查询与顶点 person:josh(vertex_id=“1:josh”) 相连且 label 为 created 的边

Method & Url

GET http://127.0.0.1:8080/graphs/hugegraph/graph/edges?vertex_id="1:josh"&direction=BOTH&label=created&properties={}

Response Status

Response Body

{
    "edges": [
        {
            "id": "S1:josh>1>>S2:lop",
            "label": "created",
            "type": "edge",
            "inVLabel": "software",
            "outVLabel": "person",
            "inV": "2:lop",
            "outV": "1:josh",
            "properties": {
                "date": "20091111",
                "weight": 0.4
            }
        },
        {
            "id": "S1:josh>1>>S2:ripple",
            "label": "created",
            "type": "edge",
            "inVLabel": "software",
            "outVLabel": "person",
            "inV": "2:ripple",
            "outV": "1:josh",
            "properties": {
                "date": "20171210",
                "weight": 1
            }
        }
    ]
}

分页查询所有边，获取第一页（page不带参数值），限定3条

Method & Url

GET http://127.0.0.1:8080/graphs/hugegraph/graph/edges?page&limit=3

Response Status

Response Body

{
	"edges": [{
			"id": "S1:peter>2>>S2:lop",
			"label": "created",
			"type": "edge",
			"inVLabel": "software",
			"outVLabel": "person",
			"inV": "2:lop",
			"outV": "1:peter",
			"properties": {
				"weight": 0.2,
				"date": "20170324"
			}
		},
		{
			"id": "S1:josh>2>>S2:lop",
			"label": "created",
			"type": "edge",
			"inVLabel": "software",
			"outVLabel": "person",
			"inV": "2:lop",
			"outV": "1:josh",
			"properties": {
				"weight": 0.4,
				"date": "20091111"
			}
		},
		{
			"id": "S1:josh>2>>S2:ripple",
			"label": "created",
			"type": "edge",
			"inVLabel": "software",
			"outVLabel": "person",
			"inV": "2:ripple",
			"outV": "1:josh",
			"properties": {
				"weight": 1,
				"date": "20171210"
			}
		}
	],
	"page": "002500100753313a6a6f73681210010004000000020953323a726970706c65f07ffffffcf07ffffffd8460d63f4b398dd2721ed4fdb7716b420004"
}

返回的body里面是带有下一页的页号信息的，"page": "002500100753313a6a6f73681210010004000000020953323a726970706c65f07ffffffcf07ffffffd8460d63f4b398dd2721ed4fdb7716b420004"，在查询下一页的时候将该值赋给page参数。

分页查询所有边，获取下一页（page带上上一页返回的page值），限定3条

Method & Url

GET http://127.0.0.1:8080/graphs/hugegraph/graph/edges?page=002500100753313a6a6f73681210010004000000020953323a726970706c65f07ffffffcf07ffffffd8460d63f4b398dd2721ed4fdb7716b420004&limit=3

Response Status

Response Body

{
	"edges": [{
			"id": "S1:marko>1>20130220>S1:josh",
			"label": "knows",
			"type": "edge",
			"inVLabel": "person",
			"outVLabel": "person",
			"inV": "1:josh",
			"outV": "1:marko",
			"properties": {
				"weight": 1,
				"date": "20130220"
			}
		},
		{
			"id": "S1:marko>1>20160110>S1:vadas",
			"label": "knows",
			"type": "edge",
			"inVLabel": "person",
			"outVLabel": "person",
			"inV": "1:vadas",
			"outV": "1:marko",
			"properties": {
				"weight": 0.5,
				"date": "20160110"
			}
		},
		{
			"id": "S1:marko>2>>S2:lop",
			"label": "created",
			"type": "edge",
			"inVLabel": "software",
			"outVLabel": "person",
			"inV": "2:lop",
			"outV": "1:marko",
			"properties": {
				"weight": 0.4,
				"date": "20171210"
			}
		}
	],
	"page": null
}

此时"page": null表示已经没有下一页了 (注: 后端为 Cassandra 时，为了性能考虑，返回页恰好为最后一页时，返回 page 值可能非空，通过该 page 再请求下一页数据时则返回 空数据 及 page = null，其他情况类似)

2.2.7 根据Id获取边

Method & Url

GET http://localhost:8080/graphs/hugegraph/graph/edges/S1:peter>1>>S2:lop

Response Status

Response Body

{
    "id": "S1:peter>1>>S2:lop",
    "label": "created",
    "type": "edge",
    "inVLabel": "software",
    "outVLabel": "person",
    "inV": "2:lop",
    "outV": "1:peter",
    "properties": {
        "date": "2017-5-18",
        "weight": 0.2
    }
}

2.2.8 根据Id删除边

Params

label: 边类型，可选参数

仅根据Id删除边

Method & Url

DELETE http://localhost:8080/graphs/hugegraph/graph/edges/S1:peter>1>>S2:lop

Response Status

根据Label+Id删除边

通过指定Label参数和Id来删除边时，一般来说其性能比仅根据Id删除会更好。

Method & Url

DELETE http://localhost:8080/graphs/hugegraph/graph/edges/S1:peter>1>>S2:lop?label=person