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// Copyright 2019-2025 The Wait4X Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package main is the main package for the Parallel Services example.
package main
import (
"context"
"fmt"
"log"
"time"
"github.com/go-logr/stdr"
"wait4x.dev/v3/checker"
"wait4x.dev/v3/checker/http"
"wait4x.dev/v3/checker/postgresql"
"wait4x.dev/v3/checker/redis"
"wait4x.dev/v3/waiter"
)
// main is the main function for the Parallel Services example
func main() {
// Set up a logger
stdr.SetVerbosity(4) // Set log level
logger := stdr.New(log.New(log.Writer(), "[Wait4X] ", log.LstdFlags|log.Lshortfile))
// Create a context with timeout for the entire operation
ctx, cancel := context.WithTimeout(context.Background(), 2*time.Minute)
defer cancel()
// Create checkers for different services
checkers := []checker.Checker{
// Redis checker
redis.New(
"redis://localhost:6379",
redis.WithTimeout(5*time.Second),
redis.WithExpectKey("app:status=ready"), // Check if key exists with specific value
),
// PostgreSQL checker
postgresql.New(
"postgres://postgres:password@localhost:5432/app_db?sslmode=disable",
),
// HTTP API checker
http.New(
"http://localhost:8080/health",
http.WithTimeout(3*time.Second),
http.WithExpectStatusCode(200),
http.WithExpectBodyJSON("status.healthy"),
),
}
// Set up common options for all waiters
waitOptions := []waiter.Option{
waiter.WithTimeout(time.Minute),
waiter.WithInterval(2 * time.Second),
waiter.WithBackoffPolicy(waiter.BackoffPolicyExponential),
waiter.WithBackoffCoefficient(1.5),
waiter.WithBackoffExponentialMaxInterval(15 * time.Second),
waiter.WithLogger(logger),
}
// Wait for all services in parallel
fmt.Println("Waiting for all required services to be available...")
err := waiter.WaitParallelContext(ctx, checkers, waitOptions...)
if err != nil {
log.Fatalf("Failed waiting for services: %v", err)
}
fmt.Println("All services are ready!")
// Continue with application startup
startApplication()
}
// startApplication is a helper function to start the application
func startApplication() {
fmt.Println("Starting application...")
// Your application code here
}
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