Initial commit: Complete Software Architecture course with 11 modules

- 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

modules/module5/sections/02-prometheus-grafana.md

@@ -0,0 +1,155 @@
+# Prometheus и Grafana
+
+## Навигация
+- [🏠 Главная страница курса](../../../README.md)
+- [📚 Модуль 5](../README.md)
+
+---
+
+## Prometheus
+
+**Prometheus** — система мониторинга и база данных временных рядов.
+
+### Архитектура Prometheus
+
+```
+┌─────────────────┐    ┌─────────────────┐    ┌─────────────────┐
+│   Application   │    │   Application   │    │   Application   │
+│   (Metrics)     │    │   (Metrics)     │    │   (Metrics)     │
+└─────────────────┘    └─────────────────┘    └─────────────────┘
+         │                       │                       │
+         └───────────────────────┼───────────────────────┘
+                                 │
+                    ┌─────────────────┐
+                    │   Prometheus    │
+                    │     Server      │
+                    └─────────────────┘
+                                 │
+                    ┌─────────────────┐
+                    │    Grafana      │
+                    │   (Dashboard)   │
+                    └─────────────────┘
+```
+
+### PromQL (Язык запросов Prometheus)
+
+#### Основные запросы:
+```promql
+# Простая метрика
+http_requests_total
+
+# Метрика с фильтрами
+http_requests_total{method="GET", status="200"}
+
+# Агрегация
+sum(http_requests_total) by (method)
+
+# Rate (скорость изменения)
+rate(http_requests_total[5m])
+
+# Histogram quantiles
+histogram_quantile(0.95, rate(http_request_duration_seconds_bucket[5m]))
+```
+
+#### Примеры запросов:
+```promql
+# Количество запросов в секунду
+rate(http_requests_total[5m])
+
+# Среднее время ответа
+rate(http_request_duration_seconds_sum[5m]) / rate(http_request_duration_seconds_count[5m])
+
+# 95-й перцентиль времени ответа
+histogram_quantile(0.95, rate(http_request_duration_seconds_bucket[5m]))
+
+# Ошибки в процентах
+rate(http_requests_total{status=~"5.."}[5m]) / rate(http_requests_total[5m]) * 100
+```
+
+### Spring Boot + Prometheus
+
+```java
+@Configuration
+public class PrometheusConfig {
+    @Bean
+    public MeterRegistry meterRegistry() {
+        return new PrometheusMeterRegistry(PrometheusConfig.DEFAULT);
+    }
+}
+
+@RestController
+public class MetricsController {
+    private final MeterRegistry meterRegistry;
+    
+    public MetricsController(MeterRegistry meterRegistry) {
+        this.meterRegistry = meterRegistry;
+    }
+    
+    @GetMapping("/metrics")
+    public String metrics() {
+        return ((PrometheusMeterRegistry) meterRegistry).scrape();
+    }
+}
+```
+
+## Grafana
+
+**Grafana** — платформа для визуализации метрик и создания дашбордов.
+
+### Создание дашборда
+
+```json
+{
+  "dashboard": {
+    "title": "Application Metrics",
+    "panels": [
+      {
+        "title": "Request Rate",
+        "type": "graph",
+        "targets": [
+          {
+            "expr": "rate(http_requests_total[5m])",
+            "legendFormat": "{{method}} {{endpoint}}"
+          }
+        ]
+      },
+      {
+        "title": "Response Time",
+        "type": "graph",
+        "targets": [
+          {
+            "expr": "histogram_quantile(0.95, rate(http_request_duration_seconds_bucket[5m]))",
+            "legendFormat": "95th percentile"
+          }
+        ]
+      }
+    ]
+  }
+}
+```
+
+### Алерты в Grafana
+
+```json
+{
+  "alert": {
+    "name": "High Error Rate",
+    "message": "Error rate is above 5%",
+    "conditions": [
+      {
+        "query": {
+          "params": ["A", "5m", "now"]
+        },
+        "reducer": {
+          "type": "last",
+          "params": []
+        },
+        "evaluator": {
+          "params": [0.05],
+          "type": "gt"
+        }
+      }
+    ]
+  }
+}
+```