Go: Cloud Firestore のデータを作成 (Create)

ライブラリーのインストール

go get firebase.google.com/go

firestore_create.go

// ---------------------------------------------------------------
//
//  firestore_create.go
//
//                  Dec/16/2020
//
// ---------------------------------------------------------------
package main

import (
    "context"
    "fmt"
    "log"
    "os"
    "reflect"

    "cloud.google.com/go/firestore" 
    firebase "firebase.google.com/go"
    "google.golang.org/api/option"
)

// ---------------------------------------------------------------
func data_set_proc(client *firestore.Client,ctx context.Context,
    key_in string, name_in string, population_in int, date_mod string) {
 _, err := client.Collection("cities").Doc(key_in).Set(ctx, map[string]interface{}{
    "name":  name_in,
    "population": population_in,
    "date_mod": date_mod,
    })
    if err != nil {
        log.Fatalf("Failed adding alovelace: %v", err)
    }

}

// ---------------------------------------------------------------
func main() {
    fmt.Fprintf (os.Stderr,"*** 開始 ***\n")
    // 初期化
    ctx := context.Background()
    sa := option.WithCredentialsFile("./application_default_credentials.json")
    app, err := firebase.NewApp(ctx, nil, sa)
    if err != nil {
        log.Fatalln(err)
    }

    client, err := app.Firestore(ctx)
    if err != nil {
        log.Fatalln(err)
    }

    fmt.Printf("%T\n", client)
    fmt.Printf("%T\n", ctx)

    fmt.Println(reflect.TypeOf(client))
    fmt.Println(reflect.TypeOf(ctx))

    data_set_proc(client,ctx,"t0921","宇都宮",49572,"1921-7-19")
    data_set_proc(client,ctx,"t0922","小山",63452,"1921-7-19")
    data_set_proc(client,ctx,"t0923","佐野",63452,"1921-7-19")
    data_set_proc(client,ctx,"t0924","足利",63452,"1921-7-19")
    data_set_proc(client,ctx,"t0925","日光",63452,"1921-7-19")
    data_set_proc(client,ctx,"t0926","下野",41528,"1921-7-19")

    // 切断
    defer client.Close()

    fmt.Fprintf (os.Stderr,"*** 終了 ***\n")
}

// ---------------------------------------------------------------

実行コマンド

project_id="project-dec16-2020"
echo $project_id
export GOOGLE_CLOUD_PROJECT=$project_id
#
go run firestore_create.go