From 8a295fbede0bc3a59296dfb9920633624a3bf5ef Mon Sep 17 00:00:00 2001 From: Maksim Chagin Date: Tue, 24 Jul 2018 21:49:01 +0300 Subject: [PATCH] examples: adds crud example --- examples/crud/Readme.md | 25 +++++ examples/crud/main.go | 225 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 250 insertions(+) create mode 100644 examples/crud/Readme.md create mode 100644 examples/crud/main.go diff --git a/examples/crud/Readme.md b/examples/crud/Readme.md new file mode 100644 index 00000000..9b5abb94 --- /dev/null +++ b/examples/crud/Readme.md @@ -0,0 +1,25 @@ +# Go GraphQL CRUD example + +Implementation create, read, update and delete on Go + +To run the program, go to the directory +`cd examples/crud` + +Run the example +`go run main.go` + +## Create +`http://localhost:8080/product?query=mutation+_{create(name:"Inca Kola",info:"Inca Kola is a soft drink that was created in Peru in 1935 by British immigrant Joseph Robinson Lindley using lemon verbena (wiki)",price:1.99){id,name,info,price}}` + +## Read +Get single product by id +`http://localhost:8080/product?query={product(id:1){name,info,price}}` + +Get product list +`http://localhost:8080/product?query={list{id,name,info,price}}` + +## Update +`http://localhost:8080/product?query=mutation+_{update(id:1,price:3.95){id,name,info,price}}` + +## Delete +`http://localhost:8080/product?query=mutation+_{delete(id:1){id,name,info,price}}` diff --git a/examples/crud/main.go b/examples/crud/main.go new file mode 100644 index 00000000..bdd83504 --- /dev/null +++ b/examples/crud/main.go @@ -0,0 +1,225 @@ +package main + +import ( + "encoding/json" + "fmt" + "math/rand" + "net/http" + "time" + + "github.com/graphql-go/graphql" +) + +type Product struct { + ID int64 `json:"id"` + Name string `json:"name"` + Info string `json:"info,omitempty"` + Price float64 `json:"price"` +} + +var products []Product + +var productType = graphql.NewObject( + graphql.ObjectConfig{ + Name: "Product", + Fields: graphql.Fields{ + "id": &graphql.Field{ + Type: graphql.Int, + }, + "name": &graphql.Field{ + Type: graphql.String, + }, + "info": &graphql.Field{ + Type: graphql.String, + }, + "price": &graphql.Field{ + Type: graphql.Float, + }, + }, + }, +) + +var queryType = graphql.NewObject( + graphql.ObjectConfig{ + Name: "Query", + Fields: graphql.Fields{ + /* Get (read) single product by id + http://localhost:8080/product?query={product(id:1){name,info,price}} + */ + "product": &graphql.Field{ + Type: productType, + Description: "Get product by id", + Args: graphql.FieldConfigArgument{ + "id": &graphql.ArgumentConfig{ + Type: graphql.Int, + }, + }, + Resolve: func(p graphql.ResolveParams) (interface{}, error) { + id, ok := p.Args["id"].(int) + if ok { + // Find product + for _, product := range products { + if int(product.ID) == id { + return product, nil + } + } + } + return nil, nil + }, + }, + /* Get (read) product list + http://localhost:8080/product?query={list{id,name,info,price}} + */ + "list": &graphql.Field{ + Type: graphql.NewList(productType), + Description: "Get product list", + Resolve: func(params graphql.ResolveParams) (interface{}, error) { + return products, nil + }, + }, + }, + }) + +var mutationType = graphql.NewObject(graphql.ObjectConfig{ + Name: "Mutation", + Fields: graphql.Fields{ + /* Create new product item + http://localhost:8080/product?query=mutation+_{create(name:"Inca Kola",info:"Inca Kola is a soft drink that was created in Peru in 1935 by British immigrant Joseph Robinson Lindley using lemon verbena (wiki)",price:1.99){id,name,info,price}} + */ + "create": &graphql.Field{ + Type: productType, + Description: "Create new product", + Args: graphql.FieldConfigArgument{ + "name": &graphql.ArgumentConfig{ + Type: graphql.NewNonNull(graphql.String), + }, + "info": &graphql.ArgumentConfig{ + Type: graphql.String, + }, + "price": &graphql.ArgumentConfig{ + Type: graphql.NewNonNull(graphql.Float), + }, + }, + Resolve: func(params graphql.ResolveParams) (interface{}, error) { + rand.Seed(time.Now().UnixNano()) + product := Product{ + ID: int64(rand.Intn(100000)), // generate random ID + Name: params.Args["name"].(string), + Info: params.Args["info"].(string), + Price: params.Args["price"].(float64), + } + products = append(products, product) + return product, nil + }, + }, + + /* Update product by id + http://localhost:8080/product?query=mutation+_{update(id:1,price:3.95){id,name,info,price}} + */ + "update": &graphql.Field{ + Type: productType, + Description: "Update product by id", + Args: graphql.FieldConfigArgument{ + "id": &graphql.ArgumentConfig{ + Type: graphql.NewNonNull(graphql.Int), + }, + "name": &graphql.ArgumentConfig{ + Type: graphql.String, + }, + "info": &graphql.ArgumentConfig{ + Type: graphql.String, + }, + "price": &graphql.ArgumentConfig{ + Type: graphql.Float, + }, + }, + Resolve: func(params graphql.ResolveParams) (interface{}, error) { + id, _ := params.Args["id"].(int) + name, nameOk := params.Args["name"].(string) + info, infoOk := params.Args["info"].(string) + price, priceOk := params.Args["price"].(float64) + product := Product{} + for i, p := range products { + if int64(id) == p.ID { + if nameOk { + products[i].Name = name + } + if infoOk { + products[i].Info = info + } + if priceOk { + products[i].Price = price + } + product = products[i] + break + } + } + return product, nil + }, + }, + + /* Delete product by id + http://localhost:8080/product?query=mutation+_{delete(id:1){id,name,info,price}} + */ + "delete": &graphql.Field{ + Type: productType, + Description: "Delete product by id", + Args: graphql.FieldConfigArgument{ + "id": &graphql.ArgumentConfig{ + Type: graphql.NewNonNull(graphql.Int), + }, + }, + Resolve: func(params graphql.ResolveParams) (interface{}, error) { + id, _ := params.Args["id"].(int) + product := Product{} + for i, p := range products { + if int64(id) == p.ID { + product = products[i] + // Remove from product list + products = append(products[:i], products[i+1:]...) + } + } + + return product, nil + }, + }, + }, +}) + +var schema, _ = graphql.NewSchema( + graphql.SchemaConfig{ + Query: queryType, + Mutation: mutationType, + }, +) + +func executeQuery(query string, schema graphql.Schema) *graphql.Result { + result := graphql.Do(graphql.Params{ + Schema: schema, + RequestString: query, + }) + if len(result.Errors) > 0 { + fmt.Printf("errors: %v", result.Errors) + } + return result +} + +func initProductsData(p *[]Product) { + product1 := Product{ID: 1, Name: "Chicha Morada", Info: "Chicha morada is a beverage originated in the Andean regions of Perú but is actually consumed at a national level (wiki)", Price: 7.99} + product2 := Product{ID: 2, Name: "Chicha de jora", Info: "Chicha de jora is a corn beer chicha prepared by germinating maize, extracting the malt sugars, boiling the wort, and fermenting it in large vessels (traditionally huge earthenware vats) for several days (wiki)", Price: 5.95} + product3 := Product{ID: 3, Name: "Pisco", Info: "Pisco is a colorless or yellowish-to-amber colored brandy produced in winemaking regions of Peru and Chile (wiki)", Price: 9.95} + *p = append(*p, product1, product2, product3) +} + +func main() { + // Primary data initialization + initProductsData(&products) + + http.HandleFunc("/product", func(w http.ResponseWriter, r *http.Request) { + result := executeQuery(r.URL.Query().Get("query"), schema) + json.NewEncoder(w).Encode(result) + }) + + fmt.Println("Server is running on port 8080") + http.ListenAndServe(":8080", nil) +}