xenapi: /boot/guest should point to local SR

Fixes bug 1037516

This patch creates a directory os-guest-kernels inside the local SR, and
sets up /boot/guest to be a symlink to that directory. This way
OpenStack won't pollute Dom0's filesystem.

Change-Id: If8dfe24355bd782a401fed0f2c4b423efd9c11ba

tools/xen/functions

@@ -1,10 +1,8 @@
 #!/bin/bash
 
 function xapi_plugin_location {
-    for PLUGIN_DIR in "/etc/xapi.d/plugins/" "/usr/lib/xcp/plugins/"
-    do
-        if [ -d $PLUGIN_DIR ]
-        then
+    for PLUGIN_DIR in "/etc/xapi.d/plugins/" "/usr/lib/xcp/plugins/"; do
+        if [ -d $PLUGIN_DIR ]; then
             echo $PLUGIN_DIR
             return 0
         fi
@@ -17,7 +15,13 @@ function zip_snapshot_location {
 }
 
 function create_directory_for_kernels {
-    mkdir -p "/boot/guest"
+    if [ -d "/boot/guest" ]; then
+        echo "INFO: /boot/guest directory already exists, using that" >&2
+    else
+        local LOCALPATH="$(get_local_sr_path)/os-guest-kernels"
+        mkdir -p $LOCALPATH
+        ln -s $LOCALPATH /boot/guest
+    fi
 }
 
 function extract_remote_zipball {
@@ -53,3 +57,11 @@ function install_xapi_plugins_from_zipball {
     rm -rf $EXTRACTED_FILES
     chmod a+x ${XAPI_PLUGIN_DIR}*
 }
+
+function get_local_sr {
+    xe sr-list name-label="Local storage" --minimal
+}
+
+function get_local_sr_path {
+    echo "/var/run/sr-mount/$(get_local_sr)"
+}

tools/xen/mocks

@@ -12,6 +12,18 @@ test ! -e "$LIST_OF_DIRECTORIES" && {
     exit 1
 }
 
+test ! -e "$XE_RESPONSE" && {
+    echo "Mocking is not set up properly."
+    echo "XE_RESPONSE should point to an existing file."
+    exit 1
+}
+
+test ! -e "$XE_CALLS" && {
+    echo "Mocking is not set up properly."
+    echo "XE_CALLS should point to an existing file."
+    exit 1
+}
+
 function mktemp {
     if test "${1:-}" = "-d";
     then
@@ -41,6 +53,10 @@ function rm {
     echo "rm $@" >> $LIST_OF_ACTIONS
 }
 
+function ln {
+    echo "ln $@" >> $LIST_OF_ACTIONS
+}
+
 function [ {
     if test "${1:-}" = "-d";
     then
@@ -57,3 +73,13 @@ function [ {
     echo "Mock test does not implement the requested function"
     exit 1
 }
+
+function xe {
+    cat $XE_RESPONSE
+    {
+    for i in $(seq "$#")
+    do
+        eval "echo \"\$$i\""
+    done
+    } >> $XE_CALLS
+}

tools/xen/test_functions.sh

@@ -23,15 +23,27 @@ function before_each_test {
 
     LIST_OF_ACTIONS=$(mktemp)
     truncate -s 0 $LIST_OF_ACTIONS
+
+    XE_RESPONSE=$(mktemp)
+    truncate -s 0 $XE_RESPONSE
+
+    XE_CALLS=$(mktemp)
+    truncate -s 0 $XE_CALLS
 }
 
 # Teardown
 function after_each_test {
     rm -f $LIST_OF_DIRECTORIES
     rm -f $LIST_OF_ACTIONS
+    rm -f $XE_RESPONSE
+    rm -f $XE_CALLS
 }
 
 # Helpers
+function setup_xe_response {
+    echo "$1" > $XE_RESPONSE
+}
+
 function given_directory_exists {
     echo "$1" >> $LIST_OF_DIRECTORIES
 }
@@ -44,6 +56,30 @@ function assert_previous_command_failed {
     [ "$?" != "0" ] || exit 1
 }
 
+function assert_xe_min {
+    grep -qe "^--minimal\$" $XE_CALLS
+}
+
+function assert_xe_param {
+    grep -qe "^$1\$" $XE_CALLS
+}
+
+function mock_out {
+    local FNNAME="$1"
+    local OUTPUT="$2"
+
+    . <(cat << EOF
+function $FNNAME {
+    echo "$OUTPUT"
+}
+EOF
+)
+}
+
+function assert_symlink {
+    grep -qe "^ln -s $2 $1\$" $LIST_OF_ACTIONS
+}
+
 # Tests
 function test_plugin_directory_on_xenserver {
     given_directory_exists "/etc/xapi.d/plugins/"
@@ -80,9 +116,26 @@ function test_zip_snapshot_location {
 }
 
 function test_create_directory_for_kernels {
-    (. mocks && create_directory_for_kernels)
+    (
+        . mocks
+        mock_out get_local_sr uuid1
+        create_directory_for_kernels
+    )
 
-    assert_directory_exists "/boot/guest"
+    assert_directory_exists "/var/run/sr-mount/uuid1/os-guest-kernels"
+    assert_symlink "/boot/guest" "/var/run/sr-mount/uuid1/os-guest-kernels"
+}
+
+function test_create_directory_for_kernels_existing_dir {
+    (
+        . mocks
+        given_directory_exists "/boot/guest"
+        create_directory_for_kernels
+    )
+
+    diff -u $LIST_OF_ACTIONS - << EOF
+[ -d /boot/guest ]
+EOF
 }
 
 function test_extract_remote_zipball {
@@ -107,6 +160,23 @@ function test_find_nova_plugins {
     rm -rf $tmpdir
 }
 
+function test_get_local_sr {
+    setup_xe_response "uuid123"
+
+    local RESULT=$(. mocks && get_local_sr)
+
+    [ "$RESULT" == "uuid123" ]
+
+    assert_xe_min
+    assert_xe_param "sr-list" "name-label=Local storage"
+}
+
+function test_get_local_sr_path {
+    local RESULT=$(mock_out get_local_sr "uuid1" && get_local_sr_path)
+
+    [ "/var/run/sr-mount/uuid1" == "$RESULT" ]
+}
+
 # Test runner
 [ "$1" = "" ] && {
     grep -e "^function *test_" $0 | cut -d" " -f2