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使用Graphene和SQLAlchemy通过GraphQL API更新记录

graphene-python graphql flask-sqlalchemy sqlalchemy python

4

Alexis.Rolland user2915097 · 技术社区 · 8 年前

我正在使用python包Flask、SQLAlchemy、Graphene和Graphene SQLAlchemy构建GraphQL API。我遵循了 SQLAlchemy + Flask Tutorial . 我能够执行查询和突变来创建记录。现在我想知道更新现有记录的最佳方法是什么。

这是我当前的脚本 架构。py公司 :

from graphene_sqlalchemy import SQLAlchemyObjectType
from database.batch import BatchOwner as BatchOwnerModel
import api_utils  # Custom methods to create records in database
import graphene


class BatchOwner(SQLAlchemyObjectType):
    """Batch owners."""
    class Meta:
        model = BatchOwnerModel
        interfaces = (graphene.relay.Node,)


class CreateBatchOwner(graphene.Mutation):
    """Create batch owner."""
    class Arguments:
        name = graphene.String()

    # Class attributes
    ok = graphene.Boolean()
    batch_owner = graphene.Field(lambda: BatchOwner)

    def mutate(self, info, name):
        record = {'name': name}
        api_utils.create('BatchOwner', record) # Custom methods to create records in database
        batch_owner = BatchOwner(name=name)
        ok = True
        return CreateBatchOwner(batch_owner=batch_owner, ok=ok)


class Query(graphene.ObjectType):
    """Query endpoint for GraphQL API."""
    node = graphene.relay.Node.Field()
    batch_owner = graphene.relay.Node.Field(BatchOwner)
    batch_owners = SQLAlchemyConnectionField(BatchOwner)


class Mutation(graphene.ObjectType):
    """Mutation endpoint for GraphQL API."""
    create_batch_owner = CreateBatchOwner.Field()


schema = graphene.Schema(query=Query, mutation=Mutation)

评论:

我的对象 BatchOwner 只有2个属性(Id、名称)
能够更新 批次所有者 名称,我假设需要提供数据库Id(而不是中继全局Id)作为某个更新方法的输入参数
但当我询问 批次所有者 从我的客户端,Graphene只返回base64编码的全局Id(例如: QmF0Y2hPd25lcjox ,对应于 BatchOwner:1 )

响应示例:

{
    "data": {
        "batchOwners": {
            "edges": [
                {
                    "node": {
                        "id": "QmF0Y2hPd25lcjox",
                        "name": "Alexis"
                    }
                }
            ]
        }
    }
}

我目前正在考虑的解决方案是:

创建以全局Id为参数的更新变体
解码全局Id(如何?)
使用从解码的全局Id检索的数据库Id查询数据库并更新相应的记录

有没有更好的方法?

1 回复 | 直到 8 年前

1

6

Alexis.Rolland user2915097 8 年前

我已经找到了使用该方法的解决方案 from_global_id ( documented here )

from graphql_relay.node.node import from_global_id

我将以下类添加到 架构。py公司 :

class UpdateBatchOwner(graphene.Mutation):
    """Update batch owner."""
    class Arguments:
        id = graphene.String()
        name = graphene.String()

    # Class attributes
    ok = graphene.Boolean()
    batch_owner = graphene.Field(lambda: BatchOwner)

    def mutate(self, info, id, name):
        id = from_global_id(id)
        record = {'id': id[1], 'name': name}
        api_utils.update('BatchOwner', record)
        batch_owner = BatchOwner(id=id, name=name)
        ok = True
        return UpdateBatchOwner(batch_owner=batch_owner, ok=ok)

我更新了突变类:

class Mutation(graphene.ObjectType):
    """Mutation endpoint for GraphQL API."""
    create_batch_owner = CreateBatchOwner.Field()
    update_batch_owner = UpdateBatchOwner.Field()

我想知道是否有更直接的方法可以做到这一点?