Remove Riak support

Reasons:
- Riak DB development is almost halted after Basho
- riak-erlang-client is abandoned and doesn't work
  correctly with OTP22
- Riak is slow in comparison to other databases
- Missing key ordering makes it impossible to implement range
  queries efficiently (e.g. MAM queries)

1 files changed, 4 insertions, 13 deletions

diff --git a/configure.ac b/configure.ac
index a2a2f13d1..6a294b081 100644
--- a/configure.ac
+++ b/configure.ac
@@ -109,10 +109,10 @@ AC_ARG_ENABLE(mssql,
 esac],[db_type=generic])
 
 AC_ARG_ENABLE(all,
-[AC_HELP_STRING([--enable-all], [same as --enable-odbc --enable-mysql --enable-pgsql --enable-sqlite --enable-pam --enable-zlib --enable-riak --enable-redis --enable-elixir --enable-stun --enable-sip --enable-debug --enable-tools (useful for Dialyzer checks, default: no)])],
+[AC_HELP_STRING([--enable-all], [same as --enable-odbc --enable-mysql --enable-pgsql --enable-sqlite --enable-pam --enable-zlib --enable-redis --enable-elixir --enable-stun --enable-sip --enable-debug --enable-tools (useful for Dialyzer checks, default: no)])],
 [case "${enableval}" in
-  yes) odbc=true mysql=true pgsql=true sqlite=true pam=true zlib=true riak=true redis=true elixir=true stun=true sip=true debug=true tools=true ;;
-  no) odbc=false mysql=false pgsql=false sqlite=false pam=false zlib=false riak=false redis=false elixir=false stun=false sip=false debug=false tools=false ;;
+  yes) odbc=true mysql=true pgsql=true sqlite=true pam=true zlib=true redis=true elixir=true stun=true sip=true debug=true tools=true ;;
+  no) odbc=false mysql=false pgsql=false sqlite=false pam=false zlib=false redis=false elixir=false stun=false sip=false debug=false tools=false ;;
   *) AC_MSG_ERROR(bad value ${enableval} for --enable-all) ;;
 esac],[])
 
@@ -172,14 +172,6 @@ AC_ARG_ENABLE(zlib,
   *) AC_MSG_ERROR(bad value ${enableval} for --enable-zlib) ;;
 esac],[if test "x$zlib" = "x"; then zlib=true; fi])
 
-AC_ARG_ENABLE(riak,
-[AC_HELP_STRING([--enable-riak], [enable Riak support (default: no)])],
-[case "${enableval}" in
-  yes) riak=true ;;
-  no)  riak=false ;;
-  *) AC_MSG_ERROR(bad value ${enableval} for --enable-riak) ;;
-esac],[if test "x$riak" = "x"; then riak=false; fi])
-
 AC_ARG_ENABLE(redis,
 [AC_HELP_STRING([--enable-redis], [enable Redis support (default: no)])],
 [case "${enableval}" in
@@ -275,7 +267,7 @@ if test "$sqlite" = "true"; then
 fi
 
 enabled_backends=""
-for backend in odbc mysql pgsql sqlite riak redis; do
+for backend in odbc mysql pgsql sqlite redis; do
     if eval test x\${$backend} = xtrue; then
        if test "x$enabled_backends" = "x"; then
           enabled_backends=$backend
@@ -296,7 +288,6 @@ AC_SUBST(pgsql)
 AC_SUBST(sqlite)
 AC_SUBST(pam)
 AC_SUBST(zlib)
-AC_SUBST(riak)
 AC_SUBST(redis)
 AC_SUBST(elixir)
 AC_SUBST(stun)