Alexander Abakumov
15e744da49
- Added comprehensive course structure with 11 modules - Included theoretical content, practical examples, and tasks - Multi-language code examples (Java, Rust, Node.js, Python) - Detailed analysis of architectural approaches and trade-offs - Complete caching strategies documentation - Architecture examples from real-world systems (Twitter, Netflix, Uber) - Structured navigation and learning path - Ready for educational use
93 lines
2.8 KiB
Markdown
93 lines
2.8 KiB
Markdown
# Observability
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## Навигация
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- [🏠 Главная страница курса](../../../README.md)
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- [📚 Модуль 5](../README.md)
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---
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## Три столпа Observability
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### 1. Metrics (Метрики)
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- Количественные измерения
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- Агрегированные данные
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- Хорошо для мониторинга трендов
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### 2. Logs (Логи)
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- События с временными метками
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- Детальная информация
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- Хорошо для отладки
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### 3. Traces (Трассировки)
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- Путь запроса через систему
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- Временные зависимости
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- Хорошо для анализа производительности
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## Паттерны наблюдаемости
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### 1. Health Checks
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```java
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@Component
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public class HealthIndicator implements HealthIndicator {
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@Override
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public Health health() {
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try {
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// проверка зависимостей
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boolean dbHealthy = checkDatabase();
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boolean cacheHealthy = checkCache();
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if (dbHealthy && cacheHealthy) {
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return Health.up()
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.withDetail("database", "UP")
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.withDetail("cache", "UP")
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.build();
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} else {
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return Health.down()
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.withDetail("database", dbHealthy ? "UP" : "DOWN")
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.withDetail("cache", cacheHealthy ? "UP" : "DOWN")
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.build();
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}
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} catch (Exception e) {
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return Health.down(e).build();
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}
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}
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}
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```
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### 2. Custom Metrics
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```java
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@Component
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public class BusinessMetrics {
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private final Counter ordersCreated;
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private final Timer orderProcessingTime;
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private final Gauge activeUsers;
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public BusinessMetrics(MeterRegistry meterRegistry) {
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this.ordersCreated = Counter.builder("orders.created")
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.description("Total orders created")
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.register(meterRegistry);
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this.orderProcessingTime = Timer.builder("orders.processing.time")
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.description("Order processing time")
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.register(meterRegistry);
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this.activeUsers = Gauge.builder("users.active")
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.description("Number of active users")
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.register(meterRegistry, this, obj -> obj.getActiveUsersCount());
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}
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public void recordOrderCreated() {
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ordersCreated.increment();
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}
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public void recordOrderProcessingTime(Duration duration) {
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orderProcessingTime.record(duration);
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}
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private int getActiveUsersCount() {
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// логика подсчета активных пользователей
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return 0;
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}
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}
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```
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