How to use remove mutation in Relay server? - graphql

Question

I work with an express graphql server, prepared for react-relay.
Queries and createPost mutation works correctly in graphiql interface.
There is a problem with removePost mutation.
Trying to use it, I get this responce:
"Cast to ObjectId failed for value \"{ id: '5db0026a76376e0f7c82d431'
}\" at path \"_id\" for model \"Post\".
Tell me please, what's wrong with removePost mutation. Thanks!
Post.js:
const mongoose = require('mongoose');
mongoose.Promise = global.Promise;
mongoose.connect("mongodb://localhost/relay-project", {
useNewUrlParser: true,
useUnifiedTopology: true
});
const Schema = mongoose.Schema;
const postSchema = new Schema({
title: String,
content: String
});
var PostModel = mongoose.model("Post", postSchema);
module.exports = {
getPosts: () => {
return PostModel.find().sort({_id: -1});
},
getPost: id => {
return PostModel.findOne({ _id: id });
},
createPost: post => {
return PostModel(post).save();
},
removePost: id => {
return PostModel.findByIdAndRemove(id);
}
};
Mutation.js:
const {
GraphQLObjectType,
GraphQLNonNull,
GraphQLString,
GraphQLID
} = require('graphql');
const {mutationWithClientMutationId} = require('graphql-relay');
const {Post} = require('./Post');
const PostModel = require('../model/Post');
const CreatePostMutation = mutationWithClientMutationId({
name: "CreatePost",
inputFields: {
title: {type: new GraphQLNonNull(GraphQLString)},
content: {type: new GraphQLNonNull(GraphQLString)}
},
outputFields: {
post: {
type: Post
}
},
mutateAndGetPayload: args => {
return new Promise((resolve,reject)=>{
PostModel.createPost({
title: args.title,
content: args.content
})
.then(post=>resolve({post}))
.catch(reject);
});
}
});
const RemovePostMutation = mutationWithClientMutationId({
name: "RemovePost",
inputFields: {
id: {type: GraphQLID}
},
outputFields: {
post: {
type: Post
}
},
mutateAndGetPayload: args => {
return new Promise((resolve,reject)=>{
PostModel.removePost({
id: args.id
})
.then(post=>resolve({post}))
.catch(reject);
});
}
});
const Mutation = new GraphQLObjectType({
name: "Mutation",
description: "kjhkjhkjhkjh",
fields: {
createPost: CreatePostMutation,
removePost: RemovePostMutation
}
});
module.exports = Mutation;

Answer 1

you have to convert your id to object id as mongodb save
i guess use below code for id
const toBase64 = (str: string) => {
return new Buffer(str.toString()).toString('base64')
}
const fromBase64 = (str: string) => {
return Buffer.from(str, 'base64').toString('ascii')
}

Answer 2

The working mutation is:
const RemovePostMutation = mutationWithClientMutationId({
name: "RemovePost",
inputFields: {
id: { type: new GraphQLNonNull(GraphQLString) },
},
outputFields: {
deleted: { type: GraphQLBoolean },
deletedId: { type: GraphQLString }
},
mutateAndGetPayload: async ({ id }, { viewer }) =>{
const { id: productId } = fromGlobalId(id);
const result = await PostModel.removePost(productId);
return { deletedId: id, deleted: true };
}
});
Cheers, Kiten