From ab0c3fb48532bec66c09ee1013584da117ec69ca Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20B=C3=BCrgi?= <mr.boskoop@gmail.com>
Date: Wed, 17 Oct 2018 23:25:01 +0200
Subject: [PATCH] Improve documentation on referencing build artifacts

See:
- spotify/dockerfile-maven#101
- spotify/dockerfile-maven#209
---
 README.md | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/README.md b/README.md
index ce9ce3dc..4c3a4ed6 100644
--- a/README.md
+++ b/README.md
@@ -90,6 +90,18 @@ ARG JAR_FILE
 ADD target/${JAR_FILE} /usr/share/myservice/myservice.jar
 ```
 
+**Important note**
+
+The most Maven-ish way to reference the build artifact would probably
+be to use the `project.build.directory` variable for referencing the
+'target'-directory. However, this results in an absolute path, which
+is not supported by the ADD command in the Dockerfile. Any such source
+must be inside the *context* of the Docker build and therefor must be
+referenced by a *relative path*. See https://github.com/spotify/dockerfile-maven/issues/101
+
+*Do **not** use `${project.build.directory}` as a way to reference your
+build directory.*
+
 ## What does it give me?
 
 There are many advantages to using this plugin for your builds.