[libvirt] [PATCH] virt-xml-validate: Allow input to be read from stdin

[Johannes Holmberg]

---

Hello,

I often find myself wanting to validate a domain xml without having
to save it to a file, so I've updated virt-xml-validate to support
the standard practice of reading from stdin when "-" is given as the
input file.
Of course, the validation is multipass so there still needs to be a
temporary file but I think it makes sense to hide this complexity in
virt-xml-validate and not force it onto the user.

 /Johannes
 

 tools/virt-xml-validate.in | 53 +++++++++++++++++++++++++++++++++-------------
 1 file changed, 38 insertions(+), 15 deletions(-)

diff --git a/tools/virt-xml-validate.in b/tools/virt-xml-validate.in
index a04fa06..8807f8d 100644
--- a/tools/virt-xml-validate.in
+++ b/tools/virt-xml-validate.in
@@ -17,6 +17,16 @@
 
 set -e
 
+TMPFILE=
+
+cleanup() {
+  if [ $TMPFILE ]; then
+    rm -f $TMPFILE
+  fi
+}
+
+trap cleanup EXIT
+
 case $1 in
   -h | --h | --he | --hel | --help)
     cat <<EOF
@@ -35,7 +45,7 @@ $0 (libvirt) @VERSION@
 EOF
     exit ;;
   --) shift ;;
-  -*)
+  -?*)
     echo "$0: unrecognized option '$1'" >&2
     exit 1 ;;
 esac
@@ -43,18 +53,27 @@ esac
 XMLFILE="$1"
 TYPE="$2"
 
-if [ -z "$XMLFILE" ]; then
-  echo "syntax: $0 XMLFILE [TYPE]" >&2
-  exit 1
-fi
-
-if [ ! -f "$XMLFILE" ]; then
-  echo "$0: document $XMLFILE does not exist" >&2
-  exit 2
+if [ "$XMLFILE" = "-" ]; then
+    TMPFILE=`mktemp --tmpdir virt-xml.XXXX`
+    cat > $TMPFILE
+else
+  if [ -z "$XMLFILE" ]; then
+    echo "syntax: $0 XMLFILE [TYPE]" >&2
+    exit 1
+  fi
+
+  if [ ! -f "$XMLFILE" ]; then
+    echo "$0: document $XMLFILE does not exist" >&2
+    exit 2
+  fi
 fi
 
 if [ -z "$TYPE" ]; then
-  ROOT=`xmllint --stream --debug "$XMLFILE" 2>/dev/null | grep "^0 1 " | awk '{ print $3 }'`
+  if [ $TMPFILE ]; then
+    ROOT=`cat "$TMPFILE" | xmllint --stream --debug - 2>/dev/null | grep "^0 1 " | awk '{ print $3 }'`
+  else
+    ROOT=`xmllint --stream --debug "$XMLFILE" 2>/dev/null | grep "^0 1 " | awk '{ print $3 }'`
+  fi
   case "$ROOT" in
      *domainsnapshot*) # Must come first, since *domain* is a substring
         TYPE="domainsnapshot"
@@ -99,8 +118,11 @@ if [ ! -f "$SCHEMA" ]; then
   exit 4
 fi
 
-xmllint --noout --relaxng "$SCHEMA" "$XMLFILE"
-
+if [ $TMPFILE ]; then
+  cat "$TMPFILE" | xmllint --noout --relaxng "$SCHEMA" -
+else
+  xmllint --noout --relaxng "$SCHEMA" "$XMLFILE"
+fi
 exit
 
 : <<=cut
@@ -119,9 +141,10 @@ exit
 
 Validates a libvirt XML for compliance with the published schema.
 The first compulsory argument is the path to the XML file to be
-validated. The optional second argument is the name of the schema
-to validate against. If omitted, the schema name will be inferred
-from the name of the root element in the XML document.
+validated (or - to read the XML from standard input). The optional
+second argument is the name of the schema to validate against. If
+omitted, the schema name will be inferred from the name of the root
+element in the XML document.
 
 Valid schema names currently include
 
-- 
1.9.1