[#97969662] Fix install script for Ubuntu

.dockerignore

@@ -1,3 +1,6 @@
+_site
+.vagrant
+Vagrantfile
 git
 pkg/*
 provider/provider

.gitignore

@@ -1,3 +1,4 @@
+.vagrant
 _site
 Godeps/_workspace/src/github.com/jstemmer/
 test.rb

README.md

@@ -13,10 +13,10 @@ Note that summon is still in **early stages**, we are looking for feedback and c
 ## Install
 
 If you're on Linux or OSX, use the install script. This will install the latest
-version of summon.
+version of summon. The script requires sudo to place summon in `/usr/local/bin`.
 
 ```
-curl -sSL https://raw.githubusercontent.com/conjurinc/summon/master/install.sh | sudo bash
+curl -sSL https://raw.githubusercontent.com/conjurinc/summon/master/install.sh | bash
 ```
 
 Otherwise, download the [latest release](https://github.com/conjurinc/summon/releases/latest) and unzip it to a location on your PATH.

Vagrantfile

@@ -0,0 +1,3 @@
+Vagrant.configure(2) do |config|
+  config.vm.box = "ubuntu/trusty64"
+end

install.sh

@@ -2,6 +2,11 @@
 
 set -e
 
+if [[ ! $(type -t unzip) ]]; then
+  echo "unzip is not installed, please install to continue"
+  exit 1
+fi
+
 ARCH=`uname -m`
 
 if [ "${ARCH}" != "x86_64" ]; then
@@ -18,16 +23,45 @@ if [ "${DISTRO}" != "linux" ] && [ "${DISTRO}" != "darwin"  ]; then
   exit 1
 fi
 
-LATEST_VERSION=`curl -sSL https://raw.githubusercontent.com/conjurinc/summon/master/version.go | grep -o -e "\d.\d.\d"`
+if test "x$TMPDIR" = "x"; then
+  tmp="/tmp"
+else
+  tmp=$TMPDIR
+fi
+# secure-ish temp dir creation without having mktemp available (DDoS-able but not expliotable)
+tmp_dir="$tmp/install.sh.$$"
+(umask 077 && mkdir $tmp_dir) || exit 1
+
+# do_download URL DIR
+function do_download(){
+  echo "Downloading $1"
+  if   [[ $(type -t wget) ]]; then wget -q -c -O "$2" "$1" >/dev/null
+  elif [[ $(type -t curl) ]]; then curl -sSL -C -o "$2" "$1"
+  else
+    error "Could not find wget or curl"
+    return 1
+  fi
+}
+
+# get_latest_version URL
+get_latest_version() {
+  versionloc=${tmp_dir}/summon.version
+  versionfile=$(do_download ${1} ${versionloc})
+  local version=$(cat ${versionloc} | grep -o -e "[[:digit:]].[[:digit:]]*.[[:digit:]]*")
+  echo "${version}"
+}
+
+LATEST_VERSION=$(get_latest_version 'https://raw.githubusercontent.com/conjurinc/summon/master/version.go')
 BASEURL="https://github.com/conjurinc/summon/releases/download/"
 URL=${BASEURL}"v${LATEST_VERSION}/summon_v${LATEST_VERSION}_${DISTRO}_amd64.zip"
 
-echo "Installing summon v${LATEST_VERSION} into /usr/local/bin"
 
-ZIP_PATH="/tmp/summon.zip"
-curl -sSL $URL -o ${ZIP_PATH}
+ZIP_PATH="${tmp_dir}/summon.zip"
+do_download ${URL} ${ZIP_PATH}
+
+echo "Installing summon v${LATEST_VERSION} into /usr/local/bin"
 
-unzip -q -o ${ZIP_PATH} -d /usr/local/bin
+sudo unzip -q -o ${ZIP_PATH} -d /usr/local/bin
 
 echo "Success!"
 echo "Run summon -h for usage"