resume_example.go

package resume_test

import (
	"context"
	"log"
)

func ExampleBackup() {
	backup := func(ctx context.Context, object string) error {
		job, err := resume.Call(ctx, "start", backupStart, object)
		if err != nil {
			return err
		}

		q := "SELECT * FROM " + object // TODO(bmizerany): safely build query using schema

		batch, err := resume.Call(ctx, "query", backupQuery, job, q)
		if err != nil {
			return err
		}

		results, err := resume.Call(ctx, "wait", backupWait, batch)
		if err != nil {
			return err
		}

		g := resume.NewGroup("results", ctx)
		for _, r := range results {
			g.Go("process", backupResult, r.URL)
		}
		if err := g.Wait(); err != nil {
			return err
		}

		sum, err := resume.Call(ctx, "finish", backupFinish)
		if err != nil {
			return err
		}
	}

	// optional: Type / Sequence annotations
	// s := resume.NewAnnotation(ctx)
	// s.Handle(1, "backup", "createJob")
	// s.Handle(1, "backup", "query")
	// s.Handle(1, "backup", "wait")
	// s.Handle(1, "backup", "results")
	// s.Handle(10000, "backup", "results", "process")

	log.Fatal(resume.Run(ctx, s))
}