[SPARK-5188][BUILD] make-distribution.sh should support curl, not only wget to get Tachyon

When we use `make-distribution.sh` with `--with-tachyon` option, Tachyon will be downloaded by `wget` command but some systems don't have `wget` by default (MacOS X doesn't have).
Other scripts like build/mvn, build/sbt support not only `wget` but also `curl` so `make-distribution.sh` should support `curl` too.

Author: Kousuke Saruta <sarutak@oss.nttdata.co.jp>

Closes #3988 from sarutak/SPARK-5188 and squashes the following commits:

0f546e0 [Kousuke Saruta] Merge branch 'master' of git://git.apache.org/spark into SPARK-5188
010e884 [Kousuke Saruta] Merge branch 'SPARK-5188' of github.com:sarutak/spark into SPARK-5188
163687e [Kousuke Saruta] Fixed a merge conflict
e24e01b [Kousuke Saruta] Merge branch 'master' of git://git.apache.org/spark into SPARK-5188
3daf1f1 [Kousuke Saruta] Merge branch 'master' of git://git.apache.org/spark into SPARK-5188
3caa4cb [Kousuke Saruta] Merge branch 'master' of git://git.apache.org/spark into SPARK-5188
7cc8255 [Kousuke Saruta] Fix to use \$MVN instead of mvn
a3e908b [Kousuke Saruta] Fixed style
2db9fbf [Kousuke Saruta] Removed redirection from the logic which checks the existence of commands
1e4c7e0 [Kousuke Saruta] Used "command" command instead of "type" command
83b49b5 [Kousuke Saruta] Modified make-distribution.sh so that we use curl, not only wget to get tachyon

build/mvn

@@ -48,11 +48,11 @@ install_app() {
     # check if we already have the tarball
     # check if we have curl installed
     # download application
-    [ ! -f "${local_tarball}" ] && [ -n "`which curl 2>/dev/null`" ] && \
+    [ ! -f "${local_tarball}" ] && [ $(command -v curl) ] && \
       echo "exec: curl ${curl_opts} ${remote_tarball}" && \
       curl ${curl_opts} "${remote_tarball}" > "${local_tarball}"
     # if the file still doesn't exist, lets try `wget` and cross our fingers
-    [ ! -f "${local_tarball}" ] && [ -n "`which wget 2>/dev/null`" ] && \
+    [ ! -f "${local_tarball}" ] && [ $(command -v wget) ] && \
       echo "exec: wget ${wget_opts} ${remote_tarball}" && \
       wget ${wget_opts} -O "${local_tarball}" "${remote_tarball}"
     # if both were unsuccessful, exit

build/sbt-launch-lib.bash

@@ -50,9 +50,9 @@ acquire_sbt_jar () {
     # Download
     printf "Attempting to fetch sbt\n"
     JAR_DL="${JAR}.part"
-    if hash curl 2>/dev/null; then
+    if [ $(command -v curl) ]; then
       (curl --silent ${URL1} > "${JAR_DL}" || curl --silent ${URL2} > "${JAR_DL}") && mv "${JAR_DL}" "${JAR}"
-    elif hash wget 2>/dev/null; then
+    elif [ $(command -v wget) ]; then
       (wget --quiet ${URL1} -O "${JAR_DL}" || wget --quiet ${URL2} -O "${JAR_DL}") && mv "${JAR_DL}" "${JAR}"
     else
       printf "You do not have curl or wget installed, please install sbt manually from http://www.scala-sbt.org/\n"

dev/check-license

@@ -27,17 +27,17 @@ acquire_rat_jar () {
   if [[ ! -f "$rat_jar" ]]; then
     # Download rat launch jar if it hasn't been downloaded yet
     if [ ! -f "$JAR" ]; then
-    # Download
-    printf "Attempting to fetch rat\n"
-    JAR_DL="${JAR}.part"
-    if hash curl 2>/dev/null; then
-      curl --silent "${URL}" > "$JAR_DL" && mv "$JAR_DL" "$JAR"
-    elif hash wget 2>/dev/null; then
-      wget --quiet ${URL} -O "$JAR_DL" && mv "$JAR_DL" "$JAR"
-    else
-      printf "You do not have curl or wget installed, please install rat manually.\n"
-      exit -1
-    fi
+      # Download
+      printf "Attempting to fetch rat\n"
+      JAR_DL="${JAR}.part"
+      if [ $(command -v curl) ]; then
+        curl --silent "${URL}" > "$JAR_DL" && mv "$JAR_DL" "$JAR"
+      elif [ $(command -v wget) ]; then
+        wget --quiet ${URL} -O "$JAR_DL" && mv "$JAR_DL" "$JAR"
+      else
+        printf "You do not have curl or wget installed, please install rat manually.\n"
+        exit -1
+      fi
     fi
 
     unzip -tq $JAR &> /dev/null

make-distribution.sh

@@ -32,6 +32,10 @@ SPARK_HOME="$(cd "`dirname "$0"`"; pwd)"
 DISTDIR="$SPARK_HOME/dist"
 
 SPARK_TACHYON=false
+TACHYON_VERSION="0.5.0"
+TACHYON_TGZ="tachyon-${TACHYON_VERSION}-bin.tar.gz"
+TACHYON_URL="https://github.com/amplab/tachyon/releases/download/v${TACHYON_VERSION}/${TACHYON_TGZ}"
+
 MAKE_TGZ=false
 NAME=none
 MVN="$SPARK_HOME/build/mvn"
@@ -93,7 +97,7 @@ done
 
 if [ -z "$JAVA_HOME" ]; then
   # Fall back on JAVA_HOME from rpm, if found
-  if which rpm &>/dev/null; then
+  if [ $(command -v  rpm) ]; then
     RPM_JAVA_HOME=$(rpm -E %java_home 2>/dev/null)
     if [ "$RPM_JAVA_HOME" != "%java_home" ]; then
       JAVA_HOME=$RPM_JAVA_HOME
@@ -107,7 +111,7 @@ if [ -z "$JAVA_HOME" ]; then
   exit -1
 fi
 
-if which git &>/dev/null; then
+if [ $(command -v git) ]; then
     GITREV=$(git rev-parse --short HEAD 2>/dev/null || :)
     if [ ! -z $GITREV ]; then
 	 GITREVSTRING=" (git revision $GITREV)"
@@ -115,14 +119,15 @@ if which git &>/dev/null; then
     unset GITREV
 fi
 
-if ! which "$MVN" &>/dev/null; then
+
+if [ ! $(command -v $MVN) ] ; then
     echo -e "Could not locate Maven command: '$MVN'."
     echo -e "Specify the Maven command with the --mvn flag"
     exit -1;
 fi
 
-VERSION=$(mvn help:evaluate -Dexpression=project.version 2>/dev/null | grep -v "INFO" | tail -n 1)
-SPARK_HADOOP_VERSION=$(mvn help:evaluate -Dexpression=hadoop.version $@ 2>/dev/null\
+VERSION=$($MVN help:evaluate -Dexpression=project.version 2>/dev/null | grep -v "INFO" | tail -n 1)
+SPARK_HADOOP_VERSION=$($MVN help:evaluate -Dexpression=hadoop.version $@ 2>/dev/null\
     | grep -v "INFO"\
     | tail -n 1)
 SPARK_HIVE=$($MVN help:evaluate -Dexpression=project.activeProfiles -pl sql/hive $@ 2>/dev/null\
@@ -225,16 +230,22 @@ cp -r "$SPARK_HOME/ec2" "$DISTDIR"
 
 # Download and copy in tachyon, if requested
 if [ "$SPARK_TACHYON" == "true" ]; then
-  TACHYON_VERSION="0.5.0"
-  TACHYON_URL="https://github.com/amplab/tachyon/releases/download/v${TACHYON_VERSION}/tachyon-${TACHYON_VERSION}-bin.tar.gz"
-
   TMPD=`mktemp -d 2>/dev/null || mktemp -d -t 'disttmp'`
 
   pushd $TMPD > /dev/null
   echo "Fetching tachyon tgz"
-  wget "$TACHYON_URL"
 
-  tar xf "tachyon-${TACHYON_VERSION}-bin.tar.gz"
+  TACHYON_DL="${TACHYON_TGZ}.part"
+  if [ $(command -v curl) ]; then
+    curl --silent -k -L "${TACHYON_URL}" > "${TACHYON_DL}" && mv "${TACHYON_DL}" "${TACHYON_TGZ}"
+  elif [ $(command -v wget) ]; then
+    wget --quiet "${TACHYON_URL}" -O "${TACHYON_DL}" && mv "${TACHYON_DL}" "${TACHYON_TGZ}"
+  else
+    printf "You do not have curl or wget installed. please install Tachyon manually.\n"
+    exit -1
+  fi
+
+  tar xzf "${TACHYON_TGZ}"
   cp "tachyon-${TACHYON_VERSION}/core/target/tachyon-${TACHYON_VERSION}-jar-with-dependencies.jar" "$DISTDIR/lib"
   mkdir -p "$DISTDIR/tachyon/src/main/java/tachyon/web"
   cp -r "tachyon-${TACHYON_VERSION}"/{bin,conf,libexec} "$DISTDIR/tachyon"