hadoop,hbase: better default for HADOOP_CONF_DIR and HBASE_CONF_DIR

order of precedence:
- env var HADOOP_CONF_DIR for hadoop and HBASE_CONF_DIR for hbase, if set
- /etc/hadoop-conf, if present
- default confs in package

pkgs/applications/networking/cluster/hadoop/default.nix

@@ -51,7 +51,8 @@ let
           makeWrapper "$n" "$out/bin/$(basename $n)"\
             --set-default JAVA_HOME ${jdk.home}\
             --set-default HADOOP_HOME $out/lib/${untarDir}\
-            --set-default HADOOP_CONF_DIR /etc/hadoop-conf/\
+            --run "test -d /etc/hadoop-conf && export HADOOP_CONF_DIR=\''${HADOOP_CONF_DIR-'/etc/hadoop-conf/'}"\
+            --set-default HADOOP_CONF_DIR $out/lib/${untarDir}/etc/hadoop/\
             --prefix PATH : "${makeBinPath [ bash coreutils which]}"\
             --prefix JAVA_LIBRARY_PATH : "${makeLibraryPath buildInputs}"
         done

pkgs/servers/hbase/default.nix

@@ -21,7 +21,9 @@ let common = { version, hash, jdk ? jdk11_headless, tests }:
     installPhase = ''
       mkdir -p $out
       cp -R * $out
-      wrapProgram $out/bin/hbase --set-default JAVA_HOME ${jdk.home}
+      wrapProgram $out/bin/hbase --set-default JAVA_HOME ${jdk.home} \
+        --run "test -d /etc/hadoop-conf && export HBASE_CONF_DIR=\''${HBASE_CONF_DIR-'/etc/hadoop-conf/'}" \
+        --set-default HBASE_CONF_DIR "$out/conf/"
     '';
 
     passthru = { inherit tests; };