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[英]Best way for splitting GraphQL schema into different modules in express-graphql?
[英]Limit Depth on Recursive GraphQL Schema Query using graphql-sequelize resolver (Node.js, express-graphql)
我有 2 個模型,用戶和帖子。 我希望能夠在查詢帖子時獲取用戶信息,並在查詢用戶時獲取用戶的所有帖子。
他們有如下關聯:
User.hasMany(Post, {
foreignKey: 'user',
as: 'posts'
});
Post.belongsTo(User, {
foreignKey: 'id',
sourceKey: 'user',
as: 'userObject'
})
Post.addScope('defaultScope', {
include: [{ model: User, as: 'userObject' }],
}, { override: true })
User.addScope('defaultScope', {
include: [{ model: Post, as: 'posts' }],
}, { override: true })
這是我的模型
用戶.js
module.exports.userType = new GQL.GraphQLObjectType({
name: 'User',
fields: () => {
const { postType } = require('../Post/Post');
return {
id: {
type: new GQL.GraphQLNonNull(GQL.GraphQLString),
description: 'user unique id'
},
ci_username: {
type: new GQL.GraphQLNonNull(GQL.GraphQLString),
unique: true,
description: 'case INSENSITIVE username of the user'
},
username: {
type: new GQL.GraphQLNonNull(GQL.GraphQLString),
description: 'case SENSITIVE username of the user'
},
password: {
type: new GQL.GraphQLNonNull(GQL.GraphQLString),
description: 'password for the user'
},
first_name: {
type: new GQL.GraphQLNonNull(GQL.GraphQLString),
description: 'first name of user'
},
last_name: {
type: GQL.GraphQLString,
description: 'last name of user (optional)'
},
profile_picture: {
type: GQL.GraphQLString,
description: 'profile picture for the user'
},
posts: {
type: GQL.GraphQLList(postType),
description: 'list of users posts'
}
}
},
})
/** define User model for the database */
module.exports.User = db.define('user', {
id: {
type: Sequelize.UUID,
primaryKey: true,
unique: true,
},
ci_username: {
type: Sequelize.STRING,
unique: true,
},
username: Sequelize.STRING,
password: Sequelize.STRING,
first_name: Sequelize.STRING,
last_name: Sequelize.STRING,
profile_picture: Sequelize.STRING,
}, {
// Tells sequelize not to query the "CreatedAt" or "UpdatedAt" Columns
timestamps: false
})
Post.js
module.exports.postType = new GQL.GraphQLObjectType({
name: 'Post',
fields: () => {
const { userType } = require('../User/User');
return {
id: {
type: new GQL.GraphQLNonNull(GQL.GraphQLString),
description: 'post unique id'
},
name: {
type: new GQL.GraphQLNonNull(GQL.GraphQLString),
description: 'name of the post'
},
user: {
type: userType,
description: 'user object of who created the post'
},
created_at: {
type: new GQL.GraphQLNonNull(GQL.GraphQLString),
description: 'the datetime the post was created',
}
}
},
})
/** define User model for the database */
module.exports.Post = db.define('post', {
id: {
type: DataTypes.UUID,
primaryKey: true,
unique: true,
},
name: DataTypes.STRING,
user: {
type: DataTypes.STRING,
references: {
model: 'users',
key: 'id'
}
},
created_at: {
type: DataTypes.TIME,
defaultValue: DataTypes.NOW
}
}, {
// Tells sequelize not to query the "CreatedAt" or "UpdatedAt" Columns
timestamps: false
})
這是我的查詢:
所有用戶.js
const allUsers = {
type: new GQL.GraphQLList(userType),
args: {
username: {
description: 'username of the user',
type: GQL.GraphQLString,
},
// An arg with the key limit will automatically be converted to a limit on the target
limit: {
type: GQL.GraphQLInt,
default: 10
},
// An arg with the key order will automatically be converted to a order on the target
order: {
type: GQL.GraphQLString
}
},
// use graphql-sequelize resolver with the User model from database
resolve: resolver(User)
}
所有帖子.js
const allPosts = {
type: new GQL.GraphQLList(postType),
args: {
username: {
description: 'username of the user',
type: GQL.GraphQLString,
},
// An arg with the key limit will automatically be converted to a limit on the target
limit: {
type: GQL.GraphQLInt,
default: 10
},
// An arg with the key order will automatically be converted to a order on the target
order: {
type: GQL.GraphQLString
}
},
// use graphql-sequelize resolver with the Post model from database
resolve: resolver(Post)
}
我目前收到Maximum call stack size exceeded
。 我假設是因為查詢中的resolver
無限遞歸地獲取有關帖子和用戶的詳細信息。
有誰知道有什么方法可以對解析器設置深度限制? 還是不可能有這樣的遞歸查詢?
你將不得不從如圖所示,包括模型刪除默認的范圍在這里是這樣的:
Post.addScope('defaultScope', {
include: [{ model: User.scope(null), as: 'userObject' }],
}, { override: true })
User.addScope('defaultScope', {
include: [{ model: Post.scope(null), as: 'posts' }],
}, { override: true })
為了支持額外的深度,您需要為相關字段實現解析器,例如:
function resolve (user) {
if (user.posts) {
return user.posts
}
return user.getPosts()
}
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