This guide shows how to modify a Go custom DNS resolver to perform simple load balancing by predefining IP addresses and randomly selecting one for each new connection, including full code examples and test output.
The article compares a traditional if‑else/switch implementation with the Strategy pattern and a Map‑plus‑lambda approach for routing coupon‑type requests, showing each method’s code, advantages, drawbacks, and how to choose the most maintainable solution.
The article describes Vivo’s overseas sales team’s multi‑language document system, detailing its low‑maintenance i18n design that leverages the existing configuration center, a MCMS UI, and a runtime JAR to streamline project creation, translation, testing, publishing, and real‑time front‑end text updates across web and decoupled architectures.
Node.js now offers a native fetch() API—an experimental, Promise‑based HTTP client introduced in v17.5.0 that mirrors the browser Fetch API, simplifying requests, improving performance, and paving the way for future LTS support.
This article explains the Snowflake distributed ID algorithm, compares it with other ID generation methods, details its 64‑bit structure, provides a complete Java implementation with thread‑safe code, and discusses practical limits such as the 69‑year timestamp and front‑end numeric handling.
This article explains how to design a scalable multi‑account login architecture—including self‑built phone‑number registration, optimized password‑optional flows, third‑party integrations such as Weibo, and a unified user‑basic and user‑auth table schema—while also covering one‑click carrier‑based login and its advantages and drawbacks.
This article explains how Spring Security’s HttpSecurity class maintains the order of its built‑in filters using FilterOrderRegistration, demonstrates the registration and retrieval logic with code examples, and clarifies how duplicate orders are resolved during filter sorting.
This article explains how Nohost extends the Whistle packet‑capture tool into a multi‑process, multi‑user remote proxy platform, detailing its architecture, interaction flow, master‑process logic, environment injection, user‑state recording, and Whistle process management for developers and operations teams.
This article explains why Linux kernels 3.9+ allow multiple processes to bind the same port, how the REUSEPORT option implements kernel‑level load balancing, and provides step‑by‑step examples showing configuration, code snippets, and performance verification.
This article compares three Go transaction implementations, explains their trade‑offs, and presents a refined pattern that uses defer tx.Rollback() to guarantee rollback while still allowing successful commits, covering both simple and loop‑based use cases.
The article examines tiered data storage and evaluates four cache‑synchronization strategies—updating the database before the cache, deleting the cache before updating the database, updating the cache before the database, and deleting the cache after a database update—highlighting their trade‑offs and practical solutions such as delayed double deletion, message‑queue retries, and binlog‑driven cache updates.
This article details the research background, environment preparation, and three Redis‑based message‑queue implementations—using List structures, Pub/Sub, and Stream APIs—along with code examples, design considerations, testing strategies, and deployment tips for building a lightweight messaging component in Java Spring Boot.
The article introduces a real-time code coloring system for Lua-based game development, explaining its purpose, usage scenarios, core functionalities, data collection methods, architectural design, technical challenges, performance optimizations, and network communication using Django Channels.
The article analyzes the problem of data inconsistency when using caches such as Redis or local memory alongside a database, classifies data by real‑time requirements, compares four write‑through/write‑behind strategies, and proposes practical solutions like delayed double‑delete, message‑queue compensation, and binlog‑driven cache updates.
Elasticsearch 8.0 introduces major updates including 7.x REST API compatibility headers, default‑enabled security with registration tokens, protected system indices, a preview KNN search API, storage‑efficient keyword/match_only_text/text fields, faster indexing for geo_point and geo_shape, PyTorch model support, and numerous deprecations and enhancements across aggregations, allocation, analysis, authentication, cluster coordination, and engine components.
This guide presents a concise set of best‑practice rules for designing consistent, RESTful backend APIs—including naming conventions, URL structures, HTTP methods, versioning, pagination, security, and documentation tools—to help developers create clear, maintainable, and user‑friendly services.
This guide outlines a practical seven‑step methodology for mastering Redis source code, from mapping the project structure and preparing prerequisite knowledge to focusing on core execution paths, handling complex functions, exploring side modules, and iteratively filling knowledge gaps.
This article explains the concept of API idempotency, why duplicate requests occur in distributed systems, and presents a comprehensive set of server‑side and client‑side techniques—including token mechanisms, PRG pattern, unique indexes, optimistic locking, distributed locks, and idempotent state machines—to guarantee that repeated calls produce only a single effect.
This article presents a thorough Java production troubleshooting workflow, covering essential knowledge, tools, and data analysis techniques, with detailed explanations of JVM garbage collection, profiling utilities, and real‑world case studies to help engineers quickly locate and resolve performance and stability problems.
This article explains how to use the ngx_lua module in Nginx to assign traffic tags, implement header‑based or domain‑based routing, and integrate with dynamic upstreams for parallel testing, load testing, and gray‑release scenarios, providing code examples and configuration details.
Midway 3.0 was officially released on January 20, 2022, introducing multi‑version documentation, a clarified tech stack for standard, serverless, and integration projects, a redesigned API syntax with zero‑API calls, enhanced operators, Prisma ORM support, a new full‑stack suite, and a lightweight request SDK for both Node.js and browser environments.
This article compiles a comprehensive set of Tencent interview questions and detailed answers covering HashMap internals, thread safety, red‑black trees, Redis performance, MySQL indexing, TCP reliability, IO multiplexing, RPC, and system bottleneck analysis to help candidates prepare effectively.
Elasticsearch 8.0 introduces 7.x REST API compatibility headers, default‑on security features with automatic enrollment tokens, tighter protection of system indices, a preview KNN search API, storage‑saving field encodings, faster geo‑point and geo‑shape indexing, PyTorch model support, and a long list of deprecations and internal improvements.
A seemingly harmless RPC framework bug caused a 4 GB byte array allocation, leading to repeated OutOfMemoryErrors in service B after service A’s deployment, and the article walks through the diagnosis, root‑cause analysis, and a simple fix.
This article reviews Alibaba’s Java Development Manual, highlights the latest Huangshan edition’s 11 new coding and design rules—including enum immutability, NPE‑prone ternary usage, security checks, and database practices—while providing concrete code examples and practical insights for Java engineers.
This article provides a comprehensive overview of Apache Tomcat, covering its role as a Java web server, the internal components such as Server, Service, Connector, and Container, the lifecycle management, startup process, connector types, NIO handling, Comet support, and asynchronous servlet processing.
The article explains the concepts of forward and reverse proxies, compares their functions and deployment scenarios, and then introduces load balancing principles, layer classifications, and common software such as DNS‑based, reverse‑proxy, NAT, and application‑layer solutions, highlighting their use in backend architectures.
The article shares a real‑world case study of a legacy multi‑service web platform where traffic spikes exposed DB connection leaks, leading to a 90% response‑time bottleneck, and outlines four key takeaways about tail‑latency metrics, investing in tools and people, actively maintaining legacy systems, and treating every line of code as critical for performance.
This article investigates whether the Mapped Diagnostic Context (MDC) in Java logging can lead to memory leaks by analyzing its ThreadLocal implementation, running multiple thread‑pool scenarios, and comparing the findings with classic ThreadLocal leak cases.
This article explains Kafka consumer group rebalance, covering core concepts, trigger conditions, detailed protocol steps, common pitfalls like long pause times, and modern improvements such as static membership and incremental cooperative rebalance, plus practical configuration tips to minimize disruptions.
This article explains why the default InMemoryDnsResolver cannot provide load balancing, shows how to create a custom SystemDefaultDnsResolver that randomly selects IPs, and demonstrates single‑thread, multi‑thread, and single‑connection pool tests to verify the behavior.
This guide explains what Pusher is, outlines its common real‑time use cases, and provides step‑by‑step instructions for registering a Pusher account and integrating its PHP and JavaScript libraries into a Laravel project for seamless WebSocket communication.
This article walks through building a simple Netty HTTP server, explaining how thread groups, channel options, handlers, and the bind operation work together to start a server, and highlights key implementation details such as selector creation and performance‑focused choices.
kkFileView is a free, Apache‑licensed Spring Boot project that enables online preview of numerous file types—including office documents, PDFs, CAD files, images, archives, and multimedia—offering RESTful APIs, easy deployment, and extensible interfaces for developers seeking a versatile document viewer.
This article walks through the design and practical implementation of a high‑throughput red‑envelope service capable of handling 10 billion requests, covering target load calculations, hardware and software choices, client‑server coordination, performance testing, monitoring, and key takeaways for building scalable backend systems.
This tutorial explains how to install Docker, configure remote access, create a Spring Boot project in IntelliJ IDEA, add Dockerfile and Maven settings, build a Docker image, run the container, and verify the application through a browser and log inspection.
This article provides a comprehensive guide to Spring's built‑in utility classes—including Assert, ObjectUtils, StringUtils, CollectionUtils, FileCopyUtils, ResourceUtils, StreamUtils, ReflectionUtils, and AOP helpers—explaining their purpose, common methods, and usage examples to replace redundant custom code.
This article introduces how to enable SpringBoot DevTools for hot deployment, integrate Lombok to reduce boilerplate code, and use the Spring Configuration Processor for property binding hints, providing Maven dependencies, IDE settings, and example code snippets for Java backend development.
This curated list compiles numerous Chinese-language articles and tutorials covering API and interface testing techniques, including Java HttpClient usage, Spring Boot integration, socket and WebSocket testing, performance measurement, automation frameworks, and related tools, offering developers practical guidance for backend service validation.
This article provides a comprehensive overview of MyBatis, detailing its three‑layer architecture, core modules such as caching, reflection, and transaction management, as well as the complete execution process from configuration files to SQL execution, helping developers master the framework for enterprise‑level Java applications.
This article explains how to break monolithic applications into domain‑driven microservices by defining clear bounded contexts, using aggregates, applying context‑mapping and event‑storming techniques, and choosing appropriate communication patterns such as asynchronous events, CAP trade‑offs, and BFF for frontend integration.
The article argues that despite widespread criticism, PHP remains highly popular and indispensable for web development, citing its long‑standing ecosystem, ease of use, massive market share, and the practical advantages it offers over languages like Python in real‑world projects.
This article explains how to analyze, diagnose, and optimize performance problems in production business systems, covering the typical causes such as high concurrency, data growth, hardware limits, and environment changes, and detailing practical steps for hardware, OS, database, middleware, JVM tuning, code review, and APM monitoring.
This article explains the concept of middleware, demonstrates how to implement it in Go using the net/http Handler interface and the Negroni library, and provides complete code examples for logging and authentication middleware chains.
This article shares a detailed account of a backend engineer's multi‑stage interview process at Huanju (formerly YY), covering personal background, common Java and system design questions, database and caching strategies, distributed lock handling, and reflections on preparation and outcomes.
The article explains why service rate limiting is essential for high‑concurrency systems, compares it with service degradation, describes common algorithms such as counter, leaky bucket and token bucket, and shows how to implement distributed rate limiting using Redis.
IntelliJ IDEA's Stream Trace feature allows developers to visualize each step of Java Stream operations during debugging, showing element counts, intermediate results, and object details, with split and flat modes, demonstrated through a sample code that filters strings by length.
This article shares a step‑by‑step account of a candidate's three‑round ByteDance interview, covering background, technical questions on Java, JVM, Redis, MySQL, Kafka, and algorithm challenges, along with personal reflections on pacing, preparation, and why concise answers matter.
This guide explains how to configure Python's logging.handlers.SMTPHandler to email log messages, why QQ enterprise and Gmail require SSL instead of TLS, and provides a complete logging.conf example with sample code to avoid common pitfalls.
This article explains MyBatis's first‑level and second‑level caching mechanisms, demonstrates data inconsistency problems caused by joined‑table queries, and provides a custom annotation‑driven relation cache solution with code examples for configuring and validating the cache behavior.
This article explains the execution order of Spring AOP annotations, demonstrates why an @Around advice may invoke a method twice when ProceedingJoinPoint.proceed() is called multiple times, and provides corrected code to ensure proper single execution.
This guide walks you through downloading XXL-Job, setting up its database, configuring Spring Boot profiles, customizing log paths, deploying the admin console, writing a sample executor with @XxlJob, and managing tasks through the web UI, all with concrete commands and code snippets.
cURL author Daniel Stenberg announced plans to add native JSON handling, explaining its importance for REST APIs, the common pain points developers face, and introducing two new command‑line options that simplify sending JSON payloads and headers.
The article analyzes the challenges of maintaining data consistency when using both cache (local memory or Redis) and a database, classifies data by real‑time requirements, evaluates four double‑write strategies, and proposes practical solutions such as delayed double deletion, message‑queue compensation, and binlog‑driven cache updates.
This article demonstrates how to enable browser-based preview of Word, Excel, and PowerPoint files in Java by converting them to PDF streams with Apache OpenOffice and JODConverter, covering installation, Maven setup, utility code, service logic, and controller exposure.
This article introduces the Go programming language, explains why it is called Go rather than Golang, outlines its key advantages and common use cases, compares it with Python for beginners, and provides practical advice and resources for learning Go effectively.
IntelliJ IDEA's StreamTrace feature allows developers to debug Java Stream pipelines by visualizing each operation's element count, results, and object details, with step-by-step screenshots and a code example that filters strings longer than five characters.
This article explains the reasons for selecting Apache RocketMQ—its synchronous double‑write safety, strong performance under massive multi‑topic loads, rich features like transactional and delayed messages, active community support, and demonstrates how to leverage Java’s SPI mechanism to build a configurable, dynamically adjustable client architecture.
This article details a practical backend design and stress‑test that simulates 1 million concurrent users handling 100 billion WeChat red‑packet requests, covering load calculations, Go‑based implementation, QPS targets, monitoring, and performance analysis.
This article explains the fundamentals of event‑driven architecture, outlines when it should be used, describes common patterns such as event notification, state transfer, event sourcing, and CQRS, and provides a detailed example of applying these concepts in a content‑platform microservice system with code snippets and deployment considerations.
This article explains Java exception categories, how Spring's @Transactional decides which exceptions trigger a rollback, and provides practical annotation configurations to control rollback behavior for both checked and unchecked exceptions.
This comprehensive guide walks developers from essential computer‑science fundamentals through front‑end basics, Solidity programming, and DApp construction, offering curated resources and step‑by‑step instructions to become proficient in Web3 and blockchain development within a year.
This article explains how to implement fast (MD5‑based) upload, chunked upload, and resumable (break‑point) upload for large files in Java, detailing the Redis‑based status tracking, server‑side file handling with RandomAccessFile or MappedByteBuffer, and the required front‑end and back‑end coordination.
Learn how to enhance your Nginx server by creating custom 404 error pages, enabling and reading the stub_status module, increasing worker processes and connections, adjusting kernel limits, expanding header buffers, and configuring client-side caching for static assets, with step‑by‑step commands and examples.
This article shares a collection of practical Java backend development habits, covering configuration with @ConfigurationProperties, Lombok's @RequiredArgsConstructor, code modularization, exception throwing, reducing DB queries, avoiding null returns, simplifying if‑else, keeping controllers thin, IDE tips, source code reading, design patterns, and fundamental coding techniques.
This article walks through setting up Spock for Java/Groovy projects, lists required Maven dependencies, shows how to handle static‑method mocking with PowerMock and Mockito, and provides concrete code examples for mocking @Autowired components, shared objects, and defining mock behavior.
This article explains the fundamentals of web session management, compares server‑side, cookie‑based, and token‑based storage methods, discusses authentication versus authorization, and outlines security considerations and best‑practice recommendations for managing user sessions in modern web applications.
This article presents a comprehensive guide to building maintainable, extensible backend systems by covering coding conventions, branch naming, commit messages, comment standards, result‑wrapping patterns, database normalization, algorithmic improvements, concurrency handling, service layering, and practical code examples.
This article explains why distributed locks are needed beyond Java's JVM‑level locks, compares three common implementation approaches—database unique indexes, Redis SETNX, and Zookeeper ephemeral sequential nodes—and provides concrete SQL and Java code examples with analysis of re‑entrancy, release timing, and single‑point risks.
This article explains the fundamentals of RabbitMQ, compares normal and mirrored cluster modes, details Google’s large‑scale test setup, and walks through advanced plugins such as sharding, consistent‑hash exchange, federation, and high‑availability strategies for achieving million‑level message throughput.
This article explains Java 8's CompletableFuture, covering its purpose, core features such as thenCompose, thenCombine, thenAccept, thenRun, and thenApply, demonstrates practical code examples, and provides a detailed analysis of the underlying source‑code implementation for asynchronous callbacks.
This article explains Kafka's timing wheel algorithm, detailing its O(1) delay operation design, multi‑layer wheel structure, and how Kafka advances time using a DelayQueue, while comparing it with Netty and other open‑source projects.
The article outlines a comprehensive backend architecture for handling million‑level daily active users, covering DNS routing, L4/L7 load balancing, monolithic versus microservice deployment, caching, database sharding, hybrid‑cloud deployment, elastic scaling, and multi‑level degradation strategies to ensure high availability under sudden traffic spikes.
This article explains why front‑end and back‑end separation is essential, describes the SPA‑based architecture, outlines practical steps for responsibility division, development workflow, and implementation, and provides a detailed V1.0.0 API specification with request and response formats.
The proposed real‑time traffic comparison platform samples production traffic, replays mock requests, and checks database records, MQ messages, API parameters, and responses against a reference version, enabling near‑instant detection of regressions during refactoring, reducing test effort and release cycles while requiring instrumentation and configuration but no dedicated comparison database.
This article demonstrates how to build a token‑bucket based rate‑limiting solution in a Spring Boot application using a custom annotation, an interceptor, a bucket utility class, scheduled token generation, and global AOP exception handling to control access to APIs.
This article explains how Spring's HttpMessageConverter abstracts HTTP message conversion, shows how to read request bodies via HttpInputMessage and ServletServerHttpRequest, demonstrates a practical filter using FormHttpMessageConverter, and illustrates writing JSON responses with MappingJackson2HttpMessageConverter, all with concise code examples.
This article explains the subtle difference between 'yyyy' and 'YYYY' in Java's SimpleDateFormat, demonstrates how using the wrong pattern can cause year miscalculations—especially on December 31st—and provides code examples and a clear explanation to help developers avoid this common bug.
This guide explains how to set up a Flask backend on Windows or CentOS, generate the required signatures for WeChat's unified order API, obtain a prepay_id, and call the mini‑program wx.requestPayment interface with the correct parameters for successful payment processing.
This article walks through setting up GORM in a Go project, covering dependency management, database initialization, model definition, and practical examples of select, insert, update, delete, raw SQL execution, and transaction handling with detailed code snippets.
magic-api is a Java‑based rapid API development framework that lets developers create HTTP interfaces through a UI without writing Controllers, Services, DAOs, or XML, offering extensive database support, dynamic scripting, Swagger generation, and easy Spring Boot integration.
This article guides startup leaders through designing a complete backend technology stack, covering language choices, essential components, processes, systemization, and detailed recommendations for project management, DNS, load balancing, CDN, RPC frameworks, databases, messaging, CI/CD, monitoring, configuration, deployment, and operational best practices.
mica‑mqtt, built on t‑io, offers a simple, low‑latency, high‑performance open‑source MQTT component that integrates easily into existing services, supports multiple protocols and deployment scenarios, and includes Spring Boot starter, GraalVM compilation, and Redis‑based clustering for robust IoT solutions.
The article explains how Kafka implements delayed operations using a timing wheel with O(1) insertion and deletion, describes its parameters, multi‑level wheel design for large time spans, and the mechanism of advancing the wheel via DelayQueue and the ExpiredOperationReaper, contrasting it with Netty's approach.
The article examines the recent Xi'an health‑code system failure, highlighting that the crash stemmed from backend design flaws such as serving all static assets without a CDN, excessive bandwidth demand exceeding 125 Gbps, and inefficient QR‑code API handling.
This article explains how to design a scalable multi‑account login system by describing self‑built phone‑number authentication, optimized password‑less registration, third‑party OAuth integration, database schema separation, and one‑click carrier‑based login, while highlighting advantages, drawbacks, and implementation details.
The article explains the concepts, problem scenarios, resource granularity, rule definition, sliding‑window calculation, and implementation flow of rate limiting and circuit breaking in microservice architectures and API gateways, providing practical guidance for building robust backend services.
The article explains a typical payment‑timeout scenario and compares four backend solutions—database polling, Java DelayQueue, Redis sorted set, and RabbitMQ TTL with dead‑letter exchange—detailing their mechanisms, advantages, and drawbacks for implementing delayed task cancellation.
This article presents Bilibili’s high‑availability design, covering load‑balancing decisions, subset selection, multi‑cluster deployment, adaptive rate limiting, retry policies, timeout propagation, and chain‑failure mitigation, all illustrated with diagrams and practical SRE insights.
This article introduces Modern.js, a ByteDance‑initiated open‑source framework that unifies frontend engineering and server‑side development by offering a minimal core, integrated web server, plugin system, and progressive full‑stack features to simplify routing, rendering, API handling, and deployment for modern web applications.
This article explains the role, challenges, and solution of JD Daojia's business gateway, detailing how it aggregates multiple backend services, adopts workflow orchestration to improve code consistency, scalability, and development efficiency, and outlines future architectural considerations.
This article explains how to integrate Redis caching into PHP applications by leveraging the __call magic method to create cache, clear, and flush operations for model methods, enabling shared model layers, resource‑efficient caching, flexible data source selection, and clean, reusable code.
This article explains why third‑party payment platforms like Alipay are used, describes Alipay's payment flow, outlines the configuration steps to obtain APPID and keys, and provides a complete Python implementation for integrating Alipay into backend services.
The AiFanFan Communication system was refactored by applying domain‑driven design and micro‑services, replacing an outdated Windows C++ client and excessive middleware with a five‑layer architecture, streamlined protocols, and a cross‑platform Electron‑Vue UI, resulting in clearer modules, higher stability, reduced team size, and faster feature delivery.
The article explains common timeout points in synchronous, asynchronous, and message‑queue communication between services, and provides client‑side and server‑side strategies—including request tracing, retry policies, idempotency, fast‑fail handling, and max‑effort notifications—to mitigate these problems in backend systems.
The article details three Xianyu backend incidents where Full GC pauses caused latency spikes or outages, analyzes root causes ranging from survivor space shortage and mis‑tuned CMS to oversized async Log4j events and massive string‑concatenation logs, and presents remediation steps such as switching to G1GC, adjusting Log4j settings, and using parameterized logging to eliminate the pauses.
This article explains the Jakarta Bean Validation standard, its applicable scenarios, annotation basics, integration with Hibernate Validator, configuration options, simple and advanced usage examples—including group sequencing and multi‑field validation—along with practical code snippets and deployment considerations for backend Java development.
This article explains why and how to separate front‑end and back‑end responsibilities, introduces the SPA‑based architecture, outlines development processes, and provides a detailed API specification (including request/response formats, pagination, and special field rules) to improve collaboration and reduce integration effort.
This article explains microservice fundamentals, outlines their advantages and technical traits, and provides practical guidance on data design, database selection, polyglot persistence, scaling strategies, and why MongoDB often fits microservice architectures best.
MyBatis-Plus, a MyBatis enhancement toolkit, streamlines CRUD development, celebrates its fifth consecutive OSC popularity award, and introduces version 4.0 with a comprehensive update log that includes MyBatis 3.5.9 upgrade, dynamic mapper injection, new hooks, and numerous performance and compatibility improvements.
