Question

I’d like to configure a Play Framework on Heroku to work with Memcached.

This thread suggests I use hard-coded config values. Heroku’s documentation states the user/password/hosts are exposed as enviornment variables … is there a way to tell Play to load these directly, without using hard-coded values?

This is what I tried:

%prod.memcached=enabled
%prod.memcached.host=%MEMCACHE_SERVERS
%prod.memcached.user=%MEMCACHE_USERNAME
%prod.memcached.password=%MEMCACHE_PASSWORD

but it doesn’t seem to work

Answer 1

I found a work around for you issue. In Heroku when you configure the “Memcache Add On”
it gives you the following environment variables.

${MEMCACHE_PASSWORD}       
${MEMCACHE_SERVERS}   
${MEMCACHE_USERNAME}

but when setting the %prod.memcached.host=${MEMCACHE_SERVERS} it also needs the default port in order to operate correctly (i.e. ${MEMCACHE_SERVERS}:11211).

Therefore you can add an extra environment variable by doing the following

1. heroku config:add MEMCACHE_SERVER=${MEMCACHE_SERVERS}:11211 in your console
2. set %prod.memcached.host=${MEMCACHE_SERVER} in your conf file
3. restart your app

—or—

figure out a way to append the port(11211) at the end of ${MEMCACHE_SERVERS} environment variable in the conf file. Which I don’t know how to do because of the “:” character will throw an exception on startup.

I got the same error in play 2.x, but should work for play 1.x.