fix(oci): give write access to config dir

* create empty dir in builder stage
* copy to scratch image

fixes #2
Signed-off-by: Frederik Zorn <federdaemn@mail.de>

anki-sync-server/containerfile

@@ -12,9 +12,9 @@ ARG software_version
 ARG TARGETARCH
 ARG TARGETVARIANT
 
-# see script
+# create empty directory (to be copied into the scratch image) a. see script
 COPY ../tools/convert-arch-cargo.sh .
-RUN sh ./convert-arch-cargo.sh
+RUN mkdir /empty && sh ./convert-arch-cargo.sh
 
 # upgrade system and install dependencies:
 # protocol buffer compiler + gcc/g++ compiler for specific arch
@@ -58,6 +58,9 @@ FROM scratch
 # copy /etc/passwd because docker cannot create one in a scratch container
 COPY tools/minimal-passwd.txt /etc/passwd
 
+# copy empty directory to give 'scratch-user' access to it
+COPY --from=builder --chown=65534:65534 /empty /config
+
 # copy binary from builder
 COPY --from=builder /output/anki-sync-server /app/anki-sync-server
 

tools/minimal-passwd.txt

@@ -1 +1 @@
-scratch-user:*:65534:65534:scratch-user:/nonexistent:/sbin/nologin
+scratch-user:*:65534:65534:scratch-user:/config:/sbin/nologin