codesnips

idempotency

ruby 
class CreateWebhookEvents < ActiveRecord::Migration[7.1]
  def change
    create_table :webhook_events do |t|
      t.string :event_id, null: false
      t.string :source, null: false, default: "stripe"
      t.string :event_type, null: false

Idempotent Stripe Webhook Processing with a Unique Event Key in Rails

rails postgres webhooks
by codesnips 4 tabs
ruby 
class SyncContactJob < ApplicationJob
  queue_as :external

  BACKOFF = ->(executions) do
    (2**executions) + rand(0.0..1.0) # exponential + jitter, in seconds
  end

Exponential Backoff with Jitter for Flaky External API Calls in ActiveJob

rails activejob background-jobs
by codesnips 3 tabs
ruby 
class CreateOutboxEvents < ActiveRecord::Migration[7.1]
  def change
    create_table :outbox_events do |t|
      t.string :event_type, null: false
      t.string :aggregate_type, null: false
      t.string :aggregate_id, null: false

Transactional Outbox for Reliable Event Publishing

rails background-jobs reliability
by codesnips 4 tabs
typescript 
import { Prisma, PrismaClient } from "@prisma/client";

const prisma = new PrismaClient();

type TxClient = Prisma.TransactionClient;

Prisma transaction with retries for serialization errors

prisma postgres concurrency
by codesnips 3 tabs
javascript 
const express = require('express');
const webhookRouter = require('./webhookRouter');
const apiRouter = require('./apiRouter');

const app = express();

Verify Stripe Webhook Signatures with a Raw-Body Express Route

express stripe webhooks
by codesnips 3 tabs
java 
package com.example.reference;

import jakarta.persistence.Column;
import jakarta.persistence.Entity;
import jakarta.persistence.Id;
import jakarta.persistence.Table;

Seed Reference Data at Boot with a Spring Boot ApplicationRunner

spring-boot seeding reference-data
by codesnips 4 tabs
python 
from django.conf import settings
from django.db.models.signals import post_save
from django.dispatch import receiver

from .models import EmailOutbox

Sending Welcome Emails via a Django post_save Signal and Outbox Worker

django signals email
by codesnips 4 tabs
ruby 
class WebhookSignature
  class VerificationError < StandardError; end

  TOLERANCE = 300 # seconds

  def initialize(payload:, header:, secrets:)

Robust Webhook Verification (HMAC + Timestamp)

rails security webhooks
by codesnips 3 tabs
sql 
CREATE TYPE outbox_status AS ENUM ('pending', 'retry', 'processing', 'done', 'dead');

CREATE TABLE outbox_events (
    id           BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
    dedupe_key   TEXT        NOT NULL,
    topic        TEXT        NOT NULL,

Atomic “Read + Mark Processed” with UPDATE … RETURNING

postgres concurrency reliability
by codesnips 3 tabs
ruby 
class AddSlugToPosts < ActiveRecord::Migration[7.1]
  def change
    add_column :posts, :slug, :string, null: false
    add_index :posts, :slug, unique: true
  end
end

Database-Backed Unique Slugs with Retry

rails postgres slugs
by codesnips 4 tabs
ruby 
namespace :cleanup do
  desc "Enqueue a job to purge expired sessions"
  task expired_sessions: :environment do
    job = ExpiredSessionCleanupJob.perform_later
    Rails.logger.info("[cleanup:expired_sessions] enqueued job #{job.job_id}")
  end

Recurring Cleanup with a Rake Task and an Idempotent Active Job in Rails

rails background-jobs active-job
by codesnips 4 tabs
ruby 
require "securerandom"

class RedisMutex
  class LockError < StandardError; end

  UNLOCK_SCRIPT = <<~LUA.freeze

Redis-Based Distributed Mutex (with TTL)

rails redis concurrency
by codesnips 2 tabs