Merge pull request 'Take the database password from PGPASSWORD, not the DSN' (#9) from postgres-dsn-password into main

Reviewed-on: #9

Makefile

@@ -87,11 +87,12 @@ fmt: ## Report unformatted files
 		echo "gofmt needed:"; echo "$$unformatted"; gofmt -d .; exit 1; \
 	fi
 
-# database.dsnSecret.name has no default and the deployment `required`s it: the
+# database.dsn has no default and the deployment `required`s it: the chart
-# chart provisions no database and cannot guess where the credentials live, so a
+# provisions no database and cannot guess where it is, so a render without it is
-# render without it is meant to fail. Setting it here keeps the lint honest about
+# meant to fail. Setting it here keeps the lint honest about what a working
-# what a working install needs.
+# install needs.
-HELM_LINT_SET = --set image.tag=v0.0.0 --set database.dsnSecret.name=terdut-db
+HELM_LINT_SET = --set image.tag=v0.0.0 \
+	--set 'database.dsn=postgres://terdut@terdut-postgres:5432/terdut?sslmode=require'
 
 .PHONY: helm-lint
 helm-lint: ## Lint and render the chart

README.md

@@ -119,17 +119,24 @@ than an `Ingress`. TLS is terminated at the gateway, so the server itself never
 | `networking.listener` | `""` | Gateway listener (`sectionName`) to bind to. Empty attaches to every matching listener, **including plaintext HTTP** — set it to the HTTPS listener's name to serve TLS only |
 | `networking.servicePort` | `8080` | Port the route forwards to; keep in sync with `service.port` |
 | `bootstrap.enabled` | `true` | Runs a post-install hook that creates the first user and stores its API key in the `<release>-admin-key` Secret. Already-bootstrapped servers are left alone |
-| `database.dsnSecret.name` | `""` | **Required.** Existing Secret holding the Postgres DSN. The chart provisions no database |
+| `database.dsn` | `""` | **Required.** Postgres DSN, with no password in it. The chart provisions no database |
-| `database.dsnSecret.key` | `dsn` | Key within that Secret |
+| `database.passwordSecret.name` | `""` | Secret supplying `PGPASSWORD`. With the Zalando postgres operator, the Secret it generates for the role |
+| `database.passwordSecret.key` | `password` | Key within that Secret |
 
 The API key travels in an `Authorization: Bearer` header, so set `networking.listener` whenever the
 hostname is reachable outside a trusted network.
 
 #### The database
 
-The chart provisions no database: it takes a DSN from a Secret and expects a Postgres that already
+The chart provisions no database: it takes a DSN and expects a Postgres that already exists. In this
-exists. In this cluster the wrapper chart declares an `acid.zalan.do/v1 postgresql` CR and passes
+cluster the wrapper chart declares an `acid.zalan.do/v1 postgresql` CR; anywhere else, any reachable
-the Secret the operator writes; anywhere else, any reachable Postgres 14+ will do.
+Postgres 14+ will do.
+
+The DSN carries no password. pgx falls back to libpq's environment variables for whatever the DSN
+leaves out, so the password arrives as `PGPASSWORD` from a Secret and never appears in values, in
+the rendered manifest or in `kubectl describe pod`. With the postgres operator that Secret is the
+one it generates for the role, so a rebuild mints a new password with nothing to keep in sync —
+the same wiring miniflux uses.
 
 The server migrates its own schema on startup, so a new database only has to exist and be writable.
 

charts/terdut-server/templates/deployment.yaml

@@ -32,14 +32,18 @@ spec:
           env:
             - name: TERDUT_ADDR
               value: ":{{ .Values.service.port }}"
-            # The connection string, from a Secret: it carries the password.
-            # The wrapper chart points this at the Secret the Postgres operator
-            # writes for this database's role.
             - name: TERDUT_DB_DSN
+              value: {{ required "database.dsn is required" .Values.database.dsn | quote }}
+            {{- if .Values.database.passwordSecret.name }}
+            # The password reaches pgx through libpq's environment variable
+            # rather than through the DSN, so it stays out of the rendered
+            # manifest. pgx fills in from PG* whatever the DSN leaves out.
+            - name: PGPASSWORD
               valueFrom:
                 secretKeyRef:
-                  name: {{ required "database.dsnSecret.name is required" .Values.database.dsnSecret.name }}
+                  name: {{ .Values.database.passwordSecret.name }}
-                  key: {{ .Values.database.dsnSecret.key }}
+                  key: {{ .Values.database.passwordSecret.key }}
+            {{- end }}
             - name: TERDUT_STALE_AFTER
               value: "{{ .Values.sweeper.staleAfter }}"
             - name: TERDUT_ARCHIVE_AFTER

charts/terdut-server/values.yaml

@@ -11,16 +11,28 @@ image:
   tag: "latest"
   pullPolicy: IfNotPresent
 
-# Postgres connection, as a DSN in an existing Secret:
+# Postgres connection. The chart provisions no database; it expects one to exist.
-#   postgres://user:password@host:5432/terdut?sslmode=require
-#
-# The chart provisions no database. In this cluster the wrapper chart declares an
-# acid.zalan.do postgresql CR and points this at the Secret the operator writes;
-# anywhere else, any reachable Postgres will do.
 database:
-  dsnSecret:
+  # Required. A DSN with no password in it:
+  #   postgres://terdut@terdut-postgres:5432/terdut?sslmode=require
+  #
+  # The password is deliberately a separate setting. pgx falls back to libpq's
+  # environment variables for anything the DSN omits, so PGPASSWORD supplies it
+  # without the credential appearing in values, in the rendered manifest, or in
+  # `kubectl describe pod`.
+  dsn: ""
+  # Where PGPASSWORD comes from. With the Zalando postgres operator this is the
+  # Secret it generates for the role — `<user>.<cluster>.credentials.postgresql.acid.zalan.do`,
+  # whose keys are `username` and `password` — so a from-scratch rebuild mints a
+  # new password and the server picks it up with nothing to keep in sync.
+  #
+  # Read at process start only: rotating the password needs a pod restart.
+  #
+  # Leave name empty only if the DSN carries its own password, which puts it in
+  # the manifest.
+  passwordSecret:
     name: ""
-    key: dsn
+    key: password
 
 service:
   type: ClusterIP