chat

README

Chat App

Example app using subscriptions to build a chat room.

Server

go run ./server/server.go

Client

The react app uses two different implementation for the websocket link

• apollo-link-ws which uses the deprecated subscriptions-transport-ws library
• graphql-ws

First you need to install the dependencies

npm install

Then to run the app with the apollo-link-ws implementation do

npm run start

or to run the app with the graphql-ws implementation (and the newer graphql-transport-ws protocol) do

npm run start:graphql-transport-ws

or to run the app with the graphql-sse implementation do

npm run start:graphql-sse

Documentation

Index

• func NewExecutableSchema(cfg Config) graphql.ExecutableSchema
• type Chatroom
• type ComplexityRoot
• type Config
  • func New() Config
• type DirectiveRoot
• type Message
• type Mutation
• type MutationResolver
• type Observer
• type Query
• type QueryResolver
• type ResolverRoot
• type Subscription
• type SubscriptionResolver

Functions

func NewExecutableSchema

func NewExecutableSchema(cfg Config) graphql.ExecutableSchema

NewExecutableSchema creates an ExecutableSchema from the ResolverRoot interface.

Types

type Chatroom

type Chatroom struct {
	Name      string
	Messages  []Message
	Observers sync.Map
}

type ComplexityRoot

type ComplexityRoot struct {
	Chatroom struct {
		Messages     func(childComplexity int) int
		Name         func(childComplexity int) int
		Subscription func(childComplexity int) int
	}

	Message struct {
		CreatedAt    func(childComplexity int) int
		CreatedBy    func(childComplexity int) int
		ID           func(childComplexity int) int
		Subscription func(childComplexity int) int
		Text         func(childComplexity int) int
	}

	Mutation struct {
		Post func(childComplexity int, text string, username string, roomName string) int
	}

	Query struct {
		Room func(childComplexity int, name string) int
	}

	Subscription struct {
		MessageAdded func(childComplexity int, roomName string) int
	}
}

type Config

type Config struct {
	Schema     *ast.Schema
	Resolvers  ResolverRoot
	Directives DirectiveRoot
	Complexity ComplexityRoot
}

func New

func New() Config

type DirectiveRoot

type DirectiveRoot struct {
	User func(ctx context.Context, obj any, next graphql.Resolver, username string) (res any, err error)
}

type Message

type Message struct {
	ID           string        `json:"id"`
	Text         string        `json:"text"`
	CreatedBy    string        `json:"createdBy"`
	CreatedAt    time.Time     `json:"createdAt"`
	Subscription *Subscription `json:"subscription"`
}

type Mutation

type Mutation struct {
}

type MutationResolver

type MutationResolver interface {
	Post(ctx context.Context, text string, username string, roomName string) (*Message, error)
}

type Observer

type Observer struct {
	Username string
	Message  chan *Message
}

type Query

type Query struct {
}

type QueryResolver

type QueryResolver interface {
	Room(ctx context.Context, name string) (*Chatroom, error)
}

type ResolverRoot

type ResolverRoot interface {
	Mutation() MutationResolver
	Query() QueryResolver
	Subscription() SubscriptionResolver
}

type Subscription

type Subscription struct {
}

type SubscriptionResolver

type SubscriptionResolver interface {
	MessageAdded(ctx context.Context, roomName string) (<-chan *Message, error)
}