Ship Docker logs to Loki

Ex: gitlab.archlinux.org and the runners.

changed the description

This should work (but the files is owned by root :/):

diff --git a/roles/promtail/templates/promtail.yaml.j2 b/roles/promtail/templates/promtail.yaml.j2
index 96b4f932..b7d00acb 100644
--- a/roles/promtail/templates/promtail.yaml.j2
+++ b/roles/promtail/templates/promtail.yaml.j2
@@ -42,3 +42,19 @@ scrape_configs:
         - timestamp:
             format: 02/Jan/2006:15:04:05 -0700
             source: time_local
+  - job_name: docker
+    static_configs:
+      - targets:
+        - localhost
+        labels:
+          job: docker
+          instance: {{ ansible_fqdn }}
+          __path__: /var/lib/docker/containers/*/*.log
+    pipeline_stages:
+    - match:
+        selector: '{job="docker"}'
+        stages:
+        - docker: {}
+        - timestamp:
+            format: RFC3339Nano
+            source: time

I suppose we could configure Docker to send the logs to journald: https://docs.docker.com/config/containers/logging/journald/

mentioned in merge request !480 (merged)

mentioned in commit 0bd66f18

closed with merge request !480 (merged)