Retry access in case the settings database is locked

Create `settings::_safer_query` class proc to allow 5 tries with 1s delay; use it for `_nval_setting` and `_tval_setting` methods
This commit is contained in:
df 2020-10-18 14:53:23 +00:00
parent cefe60c722
commit 6822c833be

View File

@ -54,6 +54,21 @@ class settings {
rtschedule 0
}
proc {settings _safer_query} { queryText args } {
global settingsdb
# allow 5 (too many?) tries with 1s (too long?) delay to get access
for {set lockCnt 5} {} {sleep 1} {
try {
$settingsdb query $queryText {*}$args
} on error {msg opts} {
if {[string first "database is locked" $msg] >= 0 && [incr lockCnt -1] > 0} {
continue
}
return {*}$opts $msg
}
}
}
settings method hostname {{name ""}} {
if {$name == ""} {
# Get
@ -104,11 +119,10 @@ settings method smtp_server {{server ""}} {
}
settings method _nval_setting {name {val -1}} {
global settingsdb
if {$val == -1} {
# Get
set res [$settingsdb query "
set res [settings::_safer_query "
select nval from settings
where name = '$name'
"]
@ -118,7 +132,7 @@ settings method _nval_setting {name {val -1}} {
return 0
} else {
# Set
$settingsdb query "
settings::_safer_query "
replace into settings(name,nval)
values('$name', $val)
"
@ -127,11 +141,10 @@ settings method _nval_setting {name {val -1}} {
}
settings method _tval_setting {name {val -1} {def 0}} {
global settingsdb
if {$val eq "-1"} {
# Get
set res [$settingsdb query "
set res [settings::_safer_query "
select tval from settings
where name = '$name'
"]
@ -141,7 +154,7 @@ settings method _tval_setting {name {val -1} {def 0}} {
return $def
} else {
# Set
$settingsdb query "
settings::_safer_query "
replace into settings(name,tval)
values('$name', '%s')
" $val