docker-compose build fails badly

[fnbauer]

Trying to set up Kansa to look at the Hugo back-end component, but the build fails. Besides numerous deprecated module warnings, the proxy build fails in an unrecoverable manner:

Building proxy
Step 1/6 : FROM openresty/openresty:jessie
 ---> 277bd066963c
Step 2/6 : RUN apt-get update &&   apt-get install --no-install-recommends --no-install-suggests -y     gettext-base   && rm -rf /var/lib/apt/lists/*
 ---> Using cache
 ---> fde2cf4d470b
Step 3/6 : RUN /usr/local/openresty/luajit/bin/luarocks install lua-resty-jwt
 ---> Running in e18645a7bcf6
Warning: The directory '/root/.cache/luarocks' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing /usr/local/openresty/luajit/bin/luarocks with sudo, you may want sudo's -H flag.
Installing https://luarocks.org/lua-resty-jwt-0.2.2-0.src.rock

Error: Rockspec format 3.0 is not supported, please upgrade LuaRocks.
ERROR: Service 'proxy' failed to build: The command '/bin/sh -c /usr/local/openresty/luajit/bin/luarocks install lua-resty-jwt' returned a non-zero code: 1
Makefile:10: recipe for target 'start' failed
make: *** [start] Error 1