Postgres socket authentication (#1052)

* Allow to connect to postgres via socket auth

* Add changelog entry for new env-vars

Co-authored-by: Uku Taht <Uku.taht@gmail.com>

CHANGELOG.md

@@ -7,6 +7,8 @@ All notable changes to this project will be documented in this file.
 - New parameter `metrics` for the `/api/v1/stats/timeseries` endpoint plausible/analytics#952
 - CSV export now includes pageviews, bounce rate and visit duration in addition to visitors plausible/analytics#952
 - Send stats to multiple dashboards by configuring a comma-separated list of domains plausible/analytics#968
+- To authenticate against a local postgresql via socket authentication, the environment-variables
+  `DATABASE_SOCKET_DIR` & `DATABASE_NAME` were added.
 - Time on Page metric available in detailed Top Pages report plausible/analytics#1007
 - Glob (wildcard) based page, entry page and exit page filters plausible/analytics#1067
 - Exclusion filters for page, entry page and exit page filters plausible/analytics#1067

config/runtime.exs

@@ -109,8 +109,16 @@ config :plausible, PlausibleWeb.Endpoint,
   http: [port: port],
   secret_key_base: secret_key_base
 
+case System.get_env("DATABASE_SOCKET_DIR", "") do
+  "" ->
     config :plausible, Plausible.Repo, url: db_url
 
+  x ->
+    config :plausible, Plausible.Repo,
+      socket_dir: x,
+      database: System.get_env("DATABASE_NAME")
+end
+
 config :sentry,
   dsn: sentry_dsn,
   environment_name: env,