docker/entrypoint.sh

@@ -1,6 +1,41 @@
 #!/usr/bin/env sh
 set -e
 
+# usage: file_env VAR [DEFAULT]
+#   Set $VAR to the contents of the path specified by $VAR_FILE. Useful for docker secrets
+file_env() {
+  VAR="$1"
+  FILE_VAR="${VAR}_FILE"
+  eval "VAR_EXPANDED=\"\${$VAR}\""
+  eval "FILE_VAR_EXPANDED=\"\${$FILE_VAR}\""
+  DEFAULT="${2:-}"
+
+  if [ "${VAR_EXPANDED:-}" ] && [ "${FILE_VAR_EXPANDED:-}" ]; then
+    echo >&2 "error: both $VAR and $FILE_VAR are set (but are exclusive)"
+    exit 1
+  fi
+
+  VAL="$DEFAULT"
+  if [ "${VAR_EXPANDED:-}" ]; then
+    VAL="${VAR_EXPANDED}"
+  elif [ "${FILE_VAR_EXPANDED:-}" ]; then
+    if [ -f "${FILE_VAR_EXPANDED}" ]; then
+      VAL="$(cat "${FILE_VAR_EXPANDED}")"
+    else
+      echo >&2 "error: couldn't find file at '$FILE_VAR_EXPANDED'"
+      exit 1
+    fi
+  fi
+
+  export "$VAR"="$VAL"
+  unset "$FILE_VAR"
+}
+
+# Substitue all env vars starting with VIKUNJA and ending with _FILE
+for var in $(env | sed -n "s/^\(VIKUNJA.*\)_FILE=.*$/\1/p"); do
+  file_env "${var}"
+done
+
 if [ -n "$PUID" ] && [ "$PUID" -ne 0 ] && \
    [ -n "$PGID" ] && [ "$PGID" -ne 0 ] ; then
   echo "info: creating the new user vikunja with $PUID:$PGID"

docs/content/doc/setup/config.md

@@ -27,6 +27,31 @@ first:
     child: true
 {{< /highlight >}}
 
+## Docker
+Environment variables that contain senstitive data can be suffixed with `_FILE`. If you take the expected environment variable for the configuration 
+option with the _FILE suffix at the end, the contents of the file it points to will be used. See [Docker Swarm](https://docs.docker.com/engine/swarm/secrets/) 
+and [Docker Compose](https://docs.docker.com/compose/use-secrets/) docs for more info on using secrets.
+
+{{< highlight bash >}}
+echo "a super secure random secret" > /host/secrets/path/vikunja_service_jwtsecret
+{{< /highlight >}}
+
+{{< highlight yaml >}}
+version: '3'
+
+secrets:
+  vikunja_service_jwtsecret:
+    file: /host/secrets/path/vikunja_service_jwtsecret
+
+services:
+  api:
+    image: vikunja/api
+    secrets:
+      - vikunja_service_jwtsecret
+    environment:
+      VIKUNJA_SERVICE_JWTSECRET_FILE: /run/secrets/vikunja_service_jwtsecret
+{{< /highlight >}}
+
 # Formats
 
 Vikunja supports using `toml`, `yaml`, `hcl`, `ini`, `json`, envfile, env variables and Java Properties files.