Cache locking support

1.3
Lukas Macura 2016-12-01 10:28:14 +01:00
parent 336d120bb5
commit 4842cdaee1
1 changed files with 44 additions and 16 deletions

View File

@ -46,35 +46,56 @@ zaf_tocache(){
local key
local value
local expiry
local lockfile
local infofile
local datafile
key=$(zaf_cache_key "$1")
rm -f $ZAF_CACHE_DIR/$key $ZAF_CACHE_DIR/${key}.info
echo "$2" >$ZAF_CACHE_DIR/$key
echo "$1" >$ZAF_CACHE_DIR/${key}.info
datafile=$ZAF_CACHE_DIR/$key
lockfile=$ZAF_CACHE_DIR/${key}.lock
infofile=$ZAF_CACHE_DIR/${key}.info
[ -f $lockfile ] && return 1 # Key is locked, return
touch $lockfile
rm -f $datafile $infofile
echo "$2" >$datafile
echo "$1" >$infofile
expiry=$(zaf_date_add "$3")
zaf_trc "Cache: Saving entry $1[$key,expiry=$expiry]"
touch -m -d "$expiry" $ZAF_CACHE_DIR/${key}.info
touch -m -d "$expiry" $infofile
rm -f $lockfile
}
# Put object into cache from stdin and copy to stdout
# $1 key
# $2 lifetime in seconds
zaf_tocache_stdin(){
! [ -w $ZAF_CACHE_DIR ] && return 1
! [ -w $ZAF_CACHE_DIR ] && { cat; return 1; }
local key
local expiry
local lockfile
local infofile
local datafile
key=$(zaf_cache_key "$1")
rm -f $ZAF_CACHE_DIR/$key $ZAF_CACHE_DIR/${key}.info
cat >$ZAF_CACHE_DIR/$key
if [ -s $ZAF_CACHE_DIR/$key ]; then
datafile=$ZAF_CACHE_DIR/$key
lockfile=$ZAF_CACHE_DIR/${key}.lock
infofile=$ZAF_CACHE_DIR/${key}.info
[ -f $lockfile ] && return 1 # Key is locked, return
touch $lockfile
rm -f $datafile $infofile
cat >$datafile
if [ -s $datafile ]; then
expiry="$(zaf_date_add $2)"
echo "$1 [key=$key,expiry=$expiry]" >$ZAF_CACHE_DIR/${key}.info
echo "$1 [key=$key,expiry=$expiry]" >$infofile
zaf_trc "Cache: Saving entry $1[key=$key,expiry=$expiry]"
touch -m -d "$expiry" $ZAF_CACHE_DIR/$key.info
cat $ZAF_CACHE_DIR/$key
touch -m -d "$expiry" $infofile
cat $datafile
rm -f $lockfile
else
rm -f "$ZAF_CACHE_DIR/$key"
rm -f "$datafile"
fi
}
@ -104,12 +125,18 @@ zaf_fromcache(){
! [ -r $ZAF_CACHE_DIR ] || [ -n "$ZAF_NOCACHE" ] && return 1
local key
local value
local infofile
local datafile
key=$(zaf_cache_key "$1")
if [ -f $ZAF_CACHE_DIR/$key ]; then
! [ -f "$ZAF_CACHE_DIR/$key.info" ] && { return 3; }
if [ "$ZAF_CACHE_DIR/$key.info" -nt "$ZAF_CACHE_DIR/$key" ]; then
datafile=$ZAF_CACHE_DIR/$key
infofile=$ZAF_CACHE_DIR/${key}.info
if [ -f $datafile ]; then
! [ -f "$infofile" ] && { return 3; }
if [ "$infofile" -nt "$datafile" ]; then
zaf_trc "Cache: serving $1($key) from cache"
cat $ZAF_CACHE_DIR/$key
cat $datafile
else
zaf_trc "Cache: removing old entry $1"
rm -f "$ZAF_CACHE_DIR/$key*"
@ -121,3 +148,4 @@ zaf_fromcache(){
fi
}