switching out promtail for alloy (#22)

* rework grafana log ingestion using alloy

* fix docker-compose.yml formatting

files/alloy/README.md

@@ -0,0 +1,45 @@
+# Alloy Log Agent Configuration
+
+This directory contains the configuration for Grafana Alloy, which has replaced Promtail as the log agent in this environment.
+
+## Key Differences
+
+- Alloy uses a component-based configuration format with `.alloy` extension
+- The web UI is available at http://localhost:9080
+- Alloy can handle logs, metrics, and traces in one agent
+- Configuration is more flexible with the River language
+
+## Configuration Explanation
+
+The `config.alloy` file follows the component-based model where:
+
+1. `loki.source.file` components directly collect logs from Mattermost log files
+2. `loki.process` component parses and labels the JSON logs
+3. `loki.write` component sends the logs to Loki
+
+## Current Setup
+
+Our configuration:
+- Monitors Mattermost logs directly from mounted volumes
+- Labels all logs with `job="mattermost"` for Grafana dashboard compatibility
+- Extracts log level, message, and other metadata from JSON logs
+- Sends logs to Loki service
+
+## Converting Promtail Config to Alloy
+
+If you need to update the configuration, you can convert Promtail configs to Alloy format with:
+
+```bash
+# Example using the alloy CLI (if installed locally)
+alloy convert --source-format=promtail --output=config.alloy promtail-config.yaml
+```
+
+## Important Syntax Notes
+
+- The River language used by Alloy requires commas at the end of each key-value pair in objects
+- Trailing commas in lists and objects are supported and recommended
+
+## More Information
+
+- [Grafana Alloy Documentation](https://grafana.com/docs/alloy/latest/)
+- [Migrating from Promtail to Alloy](https://grafana.com/docs/loki/latest/send-data/alloy/migrate-from-promtail/)

files/alloy/config.alloy

@@ -0,0 +1,59 @@
+// File-based log sources
+loki.source.file "mattermost_logs" {
+  targets = [
+    { "__path__" = "/mattermost/logs/mattermost.log", "filename" = "/logs-node-1/mattermost.log", "job" = "mattermost" },
+  ]
+  forward_to = [loki.process.mm_logs_processor.receiver]
+}
+
+loki.source.file "mattermost_advanced_logs" {
+  targets = [
+    { "__path__" = "/mattermost/logs/advancedLogs.log", "filename" = "/logs-node-1/advancedLogs.log", "job" = "mattermost" },
+  ]
+  forward_to = [loki.process.mm_logs_processor.receiver]
+}
+
+loki.source.file "mattermost_ldap_logs" {
+  targets = [
+    { "__path__" = "/mattermost/logs/advancedLdapLogs.log", "filename" = "/logs-node-1/advancedLdapLogs.log", "job" = "mattermost" },
+  ]
+  forward_to = [loki.process.mm_logs_processor.receiver]
+}
+
+// Process Mattermost logs
+loki.process "mm_logs_processor" {
+  // First, try to parse as JSON
+  stage.json {
+    expressions = {
+      ts = "timestamp",
+      log_level = "level",
+      log_msg = "msg",
+      log_caller = "caller",
+    }
+  }
+
+  // Set labels based on extracted fields
+  stage.labels {
+    values = {
+      level = "log_level",
+    }
+  }
+
+  forward_to = [loki.write.loki.receiver]
+}
+
+// API endpoint for direct log pushing
+loki.source.api "push_api" {
+  http {
+    listen_address = "0.0.0.0"
+    listen_port = 9999
+  }
+  forward_to = [loki.write.loki.receiver]
+}
+
+// Send all logs to Loki
+loki.write "loki" {
+  endpoint {
+    url = "http://loki:3100/loki/api/v1/push"
+  }
+}