Add loki service

playbooks/roles/lgtm_stack/templates/config.alloy.j2

@@ -1,6 +1,6 @@
 logging {
-  level  = "info"
-  format = "logfmt"
+    level  = "info"
+    write_to = [loki.relabel.alloy_logs.receiver]
 }
 
 prometheus.remote_write "mimir" {
@@ -65,4 +65,60 @@ prometheus.scrape "{{ job.name }}" {
     forward_to = [prometheus.remote_write.mimir.receiver]
 }
 
-{% endfor %}
+{% endfor %}
+
+loki.write "loki" {
+    endpoint {
+        url = "https://{{ lgtm_stack_loki_domain }}/loki/api/v1/push"
+    }
+}
+
+loki.relabel "alloy_logs" {
+    rule {
+        target_label = "instance"
+        replacement = "{{ inventory_hostname }}"
+    }
+
+    rule {
+        target_label = "job"
+        replacement = "integrations/self"
+    }
+
+    forward_to = [loki.write.loki.receiver]
+}
+
+discovery.docker "linux" {
+    host = "unix:///var/run/docker.sock"
+
+    filter {
+        name = "label"
+        values = ["net.serguzim.logs.collect=true"]
+    }
+}
+
+loki.source.docker "default" {
+    host       = "unix:///var/run/docker.sock"
+    targets    = discovery.docker.linux.targets
+    labels     = {"app" = "docker"}
+    relabel_rules = discovery.relabel.logs_docker_containers.rules
+    forward_to = [loki.write.loki.receiver]
+}
+
+discovery.relabel "logs_docker_containers" {
+    targets = []
+    rule {
+        source_labels = ["__meta_docker_container_label_com_docker_compose_project"]
+        target_label  = "compose_project"
+    }
+
+    rule {
+        source_labels = ["__meta_docker_container_label_com_docker_compose_service"]
+        target_label  = "compose_service"
+    }
+
+    rule {
+        source_labels = ["__meta_docker_container_name"]
+        target_label  = "container_name"
+    }
+}
+