This article outlines typical problems such as domain inaccessibility, signature errors, token expiration, timeouts, HTTP 500/404 responses, inconsistent documentation, and provides practical debugging and mitigation strategies for developers working with third‑party API integrations.
Learn how to configure NGINX to force browsers to download files instead of displaying them, using Content‑Disposition headers, regex location blocks, and proper MIME handling to reduce server load and handle IE quirks.
An in‑depth tutorial demonstrates building a Netty‑based TCP client with Spring Boot, covering project architecture, module layout, message‑queue simulation, detailed Java code for client creation, connection handling, and testing endpoints, providing a complete, production‑ready demo for IoT socket communication.
Learn how to configure NGINX to force browsers to download files instead of displaying them by adding appropriate Content‑Disposition headers, handling various file types, using regex locations, and reloading the server for the changes to take effect.
This article reviews various distributed ID generation methods—including UUID, database auto‑increment, segment mode, Redis INCR, Snowflake, Meituan Leaf, Baidu UidGenerator, and Didi TinyID—explaining their principles, advantages, drawbacks, and providing Java code examples for each.
This article outlines the essential design principles, client‑side optimizations, CDN usage, clustering, caching, database tuning, and service governance techniques required to build robust, high‑traffic, high‑concurrency backend systems.
This article presents a concise, single‑file PHP solution for integrating Alipay and WeChat payment services, detailing required environment settings, configuration steps, essential code snippets, and browser‑specific handling to help developers quickly add payment functionality to their web applications.
This article provides a comprehensive overview of Kafka, covering its core value as a message queue, fundamental concepts, cluster architecture, log storage mechanisms, zero‑copy data transfer, high‑throughput and high‑availability design, consumer group behavior, rebalance strategies, and practical operational commands for managing topics, partitions, and offsets.
This article explains the step‑by‑step evolution of Redis‑based distributed lock implementations—from a simple SETNX approach to a robust solution using UUIDs, expiration, atomic Lua scripts, and finally Redisson’s high‑level lock API—illustrating common pitfalls and their fixes.
Easy Excel is a PHP library built on openspout that enables fast, low‑memory reading and writing of xlsx, csv, and ods files, providing installation steps, environment requirements, and code examples for exporting, importing, and handling Excel data in backend applications.
The article explains how to achieve idempotent order creation and update operations by using unique request identifiers, database primary‑key constraints, Redis flags, and version columns to prevent duplicate submissions and resolve ABA anomalies in distributed backend systems.
This article explains Spring's transaction propagation options, rollback mechanisms, the limitations of self‑invocation within @Transactional methods, and how to correctly use AOP proxies such as AopContext.currentProxy() and @EnableAspectJAutoProxy to ensure transactional behavior in Java backend applications.
This article explores essential API design principles—idempotency, robustness, and security—by discussing practical techniques such as request locks, database unique constraints, Redis distributed locks, token‑based authentication, JWT, and defensive coding practices to ensure reliable, safe, and maintainable backend services.
This article describes the design, technology choices, architecture, and implementation details of an automated payment channel management system that uses Redis‑based time‑series storage, custom circuit‑breaker logic, and monitoring to achieve fast fault detection, accurate alerting, and future automated failover.
This article shares a comprehensive, step‑by‑step guide to optimizing API performance, covering batch processing, asynchronous execution, caching, pre‑processing, pooling, parallelism, indexing, transaction management, deep pagination, SQL tuning, lock granularity, and code structure refactoring, all illustrated with Java examples.
This article explains how to solve the problem of message loss in WebSocket communication within a micro‑service architecture by introducing a library that uses a single configuration annotation to automatically establish inter‑instance connections, manage message routing, and support custom selectors for targeted delivery.
This article explores how Spring implements classic design patterns—Proxy, Strategy, Decorator, Singleton, Simple Factory, Factory Method, Observer, Template, and Adapter—detailing their purpose, core code snippets, and the way Spring leverages them to provide flexible, extensible, and maintainable backend functionality.
This article explains the complete lifecycle of a Spring bean—including creation, merged BeanDefinition processing, factory exposure, property population, initialization, and destruction—while illustrating the underlying source‑code mechanisms and how Spring resolves constructors, handles circular dependencies, and integrates AOP and post‑processors.
This article walks through building a Spring @EventListener demo, explains how to decouple registration logic, shows step‑by‑step debugging of the event‑listener infrastructure, and explores the internal mechanisms that register and invoke listeners during application startup and runtime.
The article presents magic-api, a Java-based rapid API development framework that lets developers create HTTP interfaces through a visual UI without writing traditional controller, service, DAO, or XML code, and provides features, quick‑start instructions, and resource links.
This article explains the principles and workflow of Single Sign‑On (SSO) and OAuth 2.0, compares their concepts, details implementation steps and grant types, and concludes with a promotional invitation to join a community offering related resources and discounts.
This article provides a step‑by‑step tutorial on analyzing a Spring Boot microservice project, configuring parent and child Maven pom files, packaging modules with Maven plugins, and deploying both backend JARs and frontend assets to Windows or Linux servers.
This article analyzes the challenges of stitching multi‑modal transport routes in Ctrip's backend, identifies performance bottlenecks through monitoring, profiling and benchmarking, and presents a series of optimizations—including code refactoring, indexing, multi‑way merge, multi‑level caching, preprocessing, multithreading, lazy computation, and JVM tuning—that collectively reduce latency and resource consumption.
The article details how a midnight interface timeout in Vivo’s e‑commerce activity system was traced to a logging bottleneck: a synchronous Log4j call blocked all threads while a cron‑driven log‑rotation script copied a 2.6 GB file, and the issue was resolved by switching to asynchronous logging with a non‑blocking appender.
This article explains how Tencent’s internal high‑availability service curriculum emphasizes architecture boundaries, unified protocol definitions using JCE, a unified PushAPI, monitoring and feedback mechanisms, and the organizational impact of aligning system and team boundaries to achieve scalable, reliable backend services.
This article compares session‑based and JWT‑based authentication, discusses their advantages, disadvantages, security and performance considerations, and provides a complete Java Spring Boot implementation—including dependency configuration, utility classes, login/logout/password update logic, and interceptor handling—using Redis for token management.
This article explains how Spring Retry's @Retryable and @Recover annotations provide a clean, annotation‑driven way to handle common retry scenarios such as message failures, remote service errors, and lock acquisition issues, while outlining configuration steps, parameter meanings, and important usage cautions.
A seemingly harmless log addition caused a NullPointerException during FastJson serialization, prompting a step‑by‑step investigation of the generated ASM serializer, JavaBeanSerializer workflow, getter detection rules, and practical code‑style guidelines to avoid similar pitfalls.
This article explains how to build a clean, maintainable backend API response format by defining a standard JSON wrapper, categorizing status codes, using a Result class with static helpers, and automatically applying the wrapper through a custom @ResponseResult annotation, interceptor, and ResponseBodyAdvice in a Spring‑based service.
This article demonstrates how to generate all possible SKU combinations in PHP by using Cartesian product on color, size, and version arrays, includes a full code example and the resulting array output.
This article reviews several Python approaches for creating scheduled or periodic jobs—including a simple while‑True loop with sleep, the Timeloop library, the built‑in sched module, the schedule package, APScheduler, Celery, and Apache Airflow—explaining their usage, advantages, limitations, and providing ready‑to‑run code samples.
A recent OpenAI investigation revealed that a bug in the redis-py client caused ChatGPT to leak conversation histories and personal details of about 1.2% of Plus users, prompting a temporary service shutdown and a rapid patch deployment.
This article explains how to solve the WebSocket message‑delivery problem in a micro‑service environment by introducing a lightweight library that uses a custom annotation to automatically forward messages between service instances, with detailed design, configuration, and code examples.
This article explains the three main Java I/O models—BIO (blocking), NIO (non‑blocking), and AIO (asynchronous)—detailing their characteristics, differences in blocking behavior, core components like Buffer, Channel, and Selector, and shows how they are applied in popular frameworks such as Netty, Mina, and Dubbo.
The article explains how Redis cache expiration can cause a cache avalanche, describes typical scenarios, and presents mitigation techniques such as semaphore-based rate limiting and fault tolerance, accompanied by a Java service example demonstrating lock, semaphore, and cache handling.
This article outlines a flash‑sale system architecture from seven perspectives—covering Nginx static‑dynamic separation, CDN caching, gateway rate‑limiting, Redis locking, MQ buffering, business processing, and database sharding—while detailing peak‑shaving, page optimization, security controls, and transaction trade‑offs for massive concurrent traffic.
This article explains the design and implementation of JD's JSF RPC framework, detailing the architecture, XML configuration of providers and consumers, Spring namespace handling, service registration, server startup, client initialization, load balancing, and the overall workflow from provider exposure to consumer invocation.
Effective application layering, as outlined by Alibaba’s coding standards, separates concerns across controller, service, manager, DAO, and other layers, ensuring maintainable, reusable code; the article explains each layer’s role, domain model conversions, and practical tips for implementing a clean, team‑wide architecture.
This article details Bilibili's thumb‑up system design, covering business capabilities, multi‑layer storage, traffic handling, disaster‑recovery strategies, and future plans to ensure a high‑traffic, reliable like service for videos, posts, comments, and more.
This article, based on a SACC 2022 talk by Huolala architect Cao Wei, explains the principles of bytecode‑enhancement, its practical implementation for large‑scale microservice monitoring, compares enhancement frameworks, shares best‑practice patterns, and explores broader applications such as service‑mesh sidecars.
This article explains how to build a Java backend service that converts Word, Excel, PowerPoint, and text files to PDF streams with OpenOffice and JODConverter, integrates the conversion utility into a Spring service and controller, and demonstrates browser‑based online preview of the documents.
This guide walks you through preparing a GitHub and Packagist account, creating a repository, initializing a Composer package (both automatically and manually), configuring PSR‑4 autoload, writing source code, and finally publishing the package by pushing to GitHub and submitting it to Packagist.
This article explains the principles and differences of the SPI mechanisms in Java, Spring, and Dubbo, covering ServiceLoader, SpringFactoriesLoader, and Dubbo's ExtensionLoader, with detailed demos, core implementation details, advantages, drawbacks, and typical usage scenarios for each framework.
This article provides PHP functions that wrap cURL to perform GET, POST, PUT, DELETE, and PATCH HTTP requests, automatically handling JSON encoding of data and decoding responses into associative arrays, with code examples for each request type.
Learn how to implement a functional HTTP/HTTPS proxy in Go, covering proxy concepts, forward and reverse types, protocol specifics, header transformations, and a complete, runnable code example that listens on TCP, parses requests, connects to target servers, and forwards traffic.
This article explains Spring's three dependency injection methods—field, constructor, and setter injection—highlights the advantages of constructor injection for avoiding null pointers and circular dependencies, and demonstrates how Lombok's @RequiredArgsConstructor can simplify bean wiring in Java backend development.
This article explains the evolution of the Java method area, analyzes bytecode generated by `String s = new String("xyz")` and `String s = "xyz"`, and clarifies why the expression creates one or two objects depending on whether the literal already exists in the constant pool.
Switchquery is a high‑performance mobile configuration delivery platform that achieves second‑level real‑time updates through a novel header‑based versioning scheme, eliminating push notifications and long‑lived connections while supporting Android, iOS, and hybrid clients with low cost and high reliability.
This article presents a comprehensive set of PHP performance‑optimization techniques, covering efficient string operations, statement usage, function design, variable handling, array manipulation and architectural choices such as compression, static pages and caching, all illustrated with concrete code examples.
Moonbox is an open‑source, JVM‑Sandbox‑based platform that records and replays traffic to generate automated regression tests, offering visual management, rich plugins, multiple deployment options, high performance and safety features, and aims to simplify testing for developers while fostering community contributions.
This article presents a comprehensive design and implementation of a real‑time cache update system that leverages Kafka‑driven database change streams, a centralized cache scheduling center, executor registration, broadcast and fail‑over scheduling, and a lightweight SDK to achieve millisecond‑level cache consistency for C‑end services.
This article walks through the step‑by‑step evolution of Redis‑based distributed lock implementations—from simple SETNX locking to atomic expiration, UUID‑based ownership, Lua‑scripted safe release, and finally using Redisson’s high‑level lock API—illustrating common pitfalls and robust solutions.
This article explains the Lombok @Accessors annotation, detailing its source code, the meaning of its fluent, chain, and prefix attributes, and demonstrates how these settings affect generated getter and setter methods, while also providing usage examples and related promotional links.
Discover a comprehensive set of practical techniques—including batch processing, asynchronous handling, caching, pre‑processing, pooling, parallel execution, indexing, transaction optimization, code refactoring, pagination, and lock granularity—to dramatically reduce API latency and improve backend efficiency, illustrated with Java code examples and diagrams.
This article introduces Java Agent technology, explains the differences between premain and agentmain modes, demonstrates how to build, package, and attach agents using Maven and the Attach API, and shows practical bytecode manipulation techniques with Instrumentation and Javassist, complete with code examples.
This article demonstrates how to integrate account username and WeChat web‑authorization login into a Spring Security application by configuring custom authentication providers, filters, tokens, and handlers, allowing users to log in without a password while leveraging WeChat OpenID verification.
This tutorial walks through enabling Docker remote connections on Linux and Windows, installing and configuring the IntelliJ IDEA Docker plugin, adding a docker‑maven‑plugin to a Spring Boot Eureka project, building Docker images, creating containers with port mapping, and setting up one‑click deployment for rapid backend development.
This guide explains how to transform a PHP array with non‑sequential keys into a zero‑based sequential array by using the built‑in array_values function, the array_merge function, and a manual foreach loop, providing code examples and output for each method.
This article explains how to configure Nginx to split access logs by day using the $time_iso8601 variable, align log timestamps with the local timezone via Docker‑Compose or Dockerfile settings, and introduces the GoAccess tool for visual log analysis.
This guide explains how to create Spring Boot scheduled tasks whose execution intervals can be changed at runtime using configurable cron expressions or periodic triggers, and provides REST endpoints to update the schedule without restarting the application.
This article presents a comprehensive overview of a flexible, layered software architecture—covering gateway, business, and foundation layers—explaining how to evolve from simple startup setups to adaptable structures that support HTTP/TCP handling, service design, component abstraction, and common technical components.
This article demonstrates how to create a Spring Boot request‑rate‑limiting solution using a custom @RequestLimit annotation, a Redis‑backed interceptor, and configuration classes, providing step‑by‑step code examples and usage instructions for both class‑level and method‑level protection.
RaftKeeper is an open‑source, C++‑implemented Raft‑based distributed consensus service that offers double‑the‑throughput, sub‑second latency, five‑nines availability, and full ZooKeeper compatibility, targeting high‑performance OLAP workloads and large‑scale backend scenarios.
This article explains three core rate‑limiting algorithms—Leaky Bucket, Token Bucket, and Sliding Window—detailing their principles, suitable scenarios, and provides complete Go implementations to help developers choose and integrate the right strategy for handling traffic spikes and protecting backend resources.
This article describes how to identify abnormal Nginx requests caused by bots like AhrefsBot and Scrapy, and provides a step‑by‑step Docker‑based solution that includes a custom Nginx configuration, agent‑deny rules, and optional Alibaba Cloud security‑group IP blocking to prevent memory spikes.
This article provides a comprehensive roundup of recent Java ecosystem developments, including new JDK 20 and 21 builds, updates to OpenJDK drafts, releases of GraalVM, Spring Framework, Quarkus, Micronaut, JobRunr, MicroStream, Hibernate, Apache projects, and related community events.
A recent Redis‑py library vulnerability caused ChatGPT to expose personal data of about 1.2% of Plus users, prompting an OpenAI apology, a detailed post‑mortem, and a series of backend and security fixes to prevent similar incidents.
This step‑by‑step tutorial shows how to configure Alibaba mirrors, install PHP 8.2, Nginx, MySQL 8, Redis 6 and Composer on Ubuntu 20.04, adjust PHP‑FPM settings, create a test PHP file, start services, and verify the full LEMP stack works within about 20 minutes.
The article analyzes post‑pandemic salary changes in China for various tech positions—including backend (Java, PHP, Python), frontend, network security, mobile, testing, operations, data analysis, algorithm engineering, and architecture—showing modest growth in most areas with notable declines for Python and Android developers.
This article explains how to design an effective multi‑level caching system for microservice environments, covering client‑side static resource caching, application‑layer CDN caching, and service‑layer Redis caching, and provides practical Nginx configuration examples to implement these caches.
This article explains the fundamental concepts of rate limiting, including time and resource dimensions, various rule types such as QPS, connection count, bandwidth, black/white lists, and distributed considerations, then details common algorithms like token bucket, leaky bucket, sliding window, and practical implementations using Nginx, Guava, Redis, and Sentinel.
This article introduces Alibaba's open‑source Canal middleware, explains its architecture and high‑availability design, walks through MySQL binlog configuration, Canal setup, and provides a complete Java client example for real‑time data synchronization, cache refresh, and task dispatch scenarios.
This article explains how to limit the number of requests an interface can receive within a specific time window in a Spring Boot application by using a custom @RequestLimit annotation, Redis for counting, and a Spring interceptor to enforce the limits, complete with full code examples and configuration steps.
This article dissects the architecture of a 12306‑style ticket‑spiking service, explaining load‑balancing strategies, weighted Nginx routing, local and remote stock deduction using Go and Redis, and demonstrates performance testing that achieves thousands of requests per second while preventing oversell and undersell.
This tutorial demonstrates how to generate PDF files in Java with iText by filling form templates, inserting images and charts, creating dynamic tables, handling page breaks, and adding custom page headers, footers, and watermarks for backend applications.
This article explains how merging similar or duplicate requests upstream using Hystrix Collapser, a custom BatchCollapser implementation, and Guava's ConcurrentHashMultiset can significantly reduce downstream load, improve throughput, and outlines their configurations, usage patterns, and suitable scenarios.
This article examines common delay‑processing scenarios such as payment timeouts and token refreshes, compares several implementation methods—including Java DelayQueue, MQ‑based delay queues, scheduled tasks, Redis ZSETs, and time wheels—highlights their advantages and drawbacks, and presents a concrete architecture and demo code for a robust, retry‑capable distributed delay component.
This guide explains how to fix common Composer dependency errors in a Laravel project by backing up and removing the composer.lock file, reinstalling dependencies, and restoring the lock file, while also showing the typical error messages that may appear.
This article explains the concepts of functional and data permissions, the advantages of RBAC, and provides a step‑by‑step guide for designing and implementing a SaaS multi‑tenant data scope permission system using Spring Boot, MyBatis Plus, and Vue.
This article explains how to build a ready‑to‑use Spring Boot starter for enterprise OSS object storage, leveraging the Amazon S3 protocol to support major providers such as Alibaba Cloud OSS, Tencent COS, Qiniu OSS, and MinIO, and includes full Maven configuration, Java code, and packaging steps.
This guide explores practical strategies for managing Elasticsearch indexes, covering management approaches, structural maintenance, data synchronization, refresh policies, and deep pagination techniques to avoid common pitfalls and ensure reliable search performance.
The article explains common pitfalls of using Spring's @Autowired, compares it with the standard @Resource annotation, and demonstrates various injection techniques—including field, setter, constructor, and Lombok-based constructor injection—through detailed code examples and best‑practice recommendations.
This article provides a comprehensive walkthrough of Spring Security’s authentication mechanism, detailing the filter chain, core security components, and the underlying source‑code flow—from UsernamePasswordAuthenticationFilter through AuthenticationManager, ProviderManager, and DaoAuthenticationProvider—illustrated with code examples and diagrams.
This article demonstrates how to build a unified processing module in Spring Boot by using AOP and HandlerInterceptor to centralize user login validation, standardize response formats, handle exceptions globally with @ControllerAdvice, and configure path prefixes, providing complete code examples and implementation details.
This article explains a step‑by‑step methodology for estimating capacity, selecting appropriate garbage collectors, sizing JVM memory regions, and tuning advanced parameters such as survivor ratio, tenuring threshold, and Metaspace to reliably support a login service that processes one million requests per day on a machine with 8 GB of RAM.
A detailed post‑mortem of Digg's disastrous v4 launch reveals how a Python function with a mutable default argument caused massive cache overloads, forced emergency fixes, and ultimately contributed to the company's downfall, offering crucial lessons for backend engineers on safe defaults and release planning.
This article details the Spring Boot startup sequence, including the run() method, creation of listeners, environment loading, application context initialization, and the role of @EnableAutoConfiguration and related annotations in automatically configuring beans and starter components.
This article explains several common techniques for measuring Java code execution time, including System.currentTimeMillis(), Spring's StopWatch utility, System.nanoTime(), and the use of new Date(), providing code examples and a brief overview of StopWatch's API for developers seeking precise performance metrics.
This article explains the definitions, differences, and typical usage scenarios of DTO, VO, BO, PO, DO, and POJO in Java backend development, provides code examples for each layer, and introduces an IDEA plugin that automates object conversion to improve code maintainability.
This article explains three Redis‑based rate‑limiting techniques—using SETNX, sorted sets, and a token‑bucket with lists—providing code examples, discussing their advantages and drawbacks, and showing how to integrate them into Java Spring applications to protect high‑concurrency services.
This article describes how the Inspiration Spaces (IS) platform implements an automated regression testing pipeline that uses SSIM image similarity, asynchronous rendering, and pre‑defined sample rooms to dramatically reduce manual effort, improve detection of rendering bugs, and streamline cross‑team collaboration.
Learn how Spring Boot 2.6.14 simplifies calling remote REST services using RestTemplate and WebClient, including automatic configuration with RestTemplateBuilder, customization options via RestTemplateCustomizer and WebClient.Builder, and detailed code examples for building, customizing, and selecting appropriate HTTP connectors.
This article explains why traditional crontab cannot meet second‑ or millisecond‑level scheduling requirements in PHP projects and demonstrates how to use Workerman and Swoole timers, including code examples for one‑time, recurring, and task‑based executions.
This article explains the concept and purpose of caching, compares local and centralized cache approaches, introduces Spring's cache support and various CacheManager implementations, details GuavaCacheManager configuration and expiration strategies, demonstrates @Cacheable usage, and discusses common pitfalls such as cache miss due to internal method calls.
This article explains the design of a compact RPC service that aggregates product benefit information, detailing how Sirector thread scheduling reduces CPU consumption and how abstract handlers and Spring prototype beans improve code maintainability and extensibility.
This article explains how to configure and implement request throttling in Django Rest Framework, walks through the relevant source code in throttling.py and views.py, demonstrates testing the limit, and shows how to trigger custom DingTalk alerts when the limit is exceeded.
This article explains the concepts of cache penetration, cache breakdown (stampede), and cache avalanche in Redis, and provides practical solutions such as parameter validation, null‑value caching, Bloom filters, mutex locks, hot‑data non‑expiration, and randomizing expiration times, accompanied by Java code examples.
This tutorial explains how to set up a Java SpringBoot service, install and configure the cpolar intranet‑penetration tool, create HTTP tunnels for local ports, test the public endpoints with Postman, reserve a fixed sub‑domain, and use cpolar's listener for request debugging.
An online service experienced severe latency due to massive GAP times, leading to repeated OutOfMemoryErrors; by analyzing monitoring data, JVM dumps, and SQL queries, the team uncovered a massive userId array causing a 1 GB count query, then implemented request limits and JVM flags to prevent recurrence.
The author shares a detailed recap of interview preparation, processes, technical questions, and personal reflections from recent backend engineering interviews at several top Chinese tech companies, highlighting the importance of solid fundamentals, Go knowledge, and systematic study resources.
