upgrade saved variable

[cyxui]

I wonder if it is possible to upgrade saved variable. For example I had a version 1 savedvar, then later I decide to make some changes and the newer one is version 2. I want to be able to retrieve the version 1 var, update it and save it as version 2. In the above scenario if I call ZO_SavedVars:NewAccountWide with version = 2 directly it will wipe the version 1 var. If I call ZO_SavedVars:NewAccountWide with version = 1 then the version 2 vars will be wiped. Any one got a good way to solve this?

[haggen]

People generally forsake the versioning of saved variables and simply use the same version number forever.

I actually drafted some *migrations* for saved variables but then figured it wouldn't have appeal. =/

[sirinsidiator]

I don't use ZO_SavedVars in my addons and instead have my own structure. It's nothing special, but it allows me to upgrade my saved vars whenever I need. You might want to take a look at AwesomeGuildStore's Settings.lua.

[Ayantir]

in your metafile you have

## SavedVariables: SOMETHING

in your lua, you have

db = ZO_SavedVars:New("SOMETHING", 2, nil, defaults, nil) -- 2 is for "version 2 here"

if you want to check v1 of your SV, just play with :

SOMETHING.Default[GetDisplayName()]

[haggen]

Originally Posted by Ayantir in your metafile you have ## SavedVariables: SOMETHING in your lua, you have db = ZO_SavedVars:New("SOMETHING", 2, nil, defaults, nil) -- 2 is for "version 2 here" if you want to check v1 of your SV, just play with : SOMETHING.Default[GetDisplayName()]

Ayantir correct if I'm wrong but I think that if you initialized a SavedVars with same name but different version then your previous data was wiped, as in:

ZO_SavedVars:New("SOMETHING", 1, nil, {x = 1})
ZO_SavedVars:New("SOMETHING", 2, nil, {}) --> version 1 is no more
SOMETHING.Default[GetDisplayName()]["x"] == nil --> true

[votan]

Originally Posted by haggen Ayantir correct if I'm wrong but I think that if you initialized a SavedVars with same name but different version then your previous data was wiped, as in: ZO_SavedVars:New("SOMETHING", 1, nil, {x = 1}) ZO_SavedVars:New("SOMETHING", 2, nil, {}) --> version 1 is no more SOMETHING.Default[GetDisplayName()]["x"] == nil --> true

Ayantir is talking about doing it before using the helper class.

local olddata = SOMETHING.Default[GetDisplayName()]
-- Check for old data and migrate
ZO_SavedVars:New("SOMETHING", 2, nil, {}) --> version 1 is no more
-- save migrated data, if exists

Which means, you have to know how the helper works.

The problem is within the helper, which saves the given version as the current version. No matter, if there is a higher version.
As soon as you query for version 1, version 2 will become version 1.

I tried what I suggested on ESO forums and it seems to work.
If you find an elegant way to get rid of the first one after the second is populated it should do it.

a bit more detailled maybe :

Manifest

## SavedVariables: MyTestsVars MyTestsVars2

MyTests.Truc = ZO_SavedVars:NewAccountWide("MyTestsVars", 1, nil, {myolddata})
MyTests.Toto = ZO_SavedVars:NewAccountWide("MyTestsVars2", 1, nil, {})

testwhichoneisempty()
rebuildnewtable()
deleteuseless()

not the cleanest as you may be stuck with the 2 names in the manifest but can be safer if you collected data through time and can't afford a wipe.

[merlight]

It's unlikely you'll want to completely change everything in the saved table, so better keep ZO_SavedVars version unchanged, and either manage your own internal version like AGS, or upgrade vars individually:

if sv.oldVar ~= nil then -- needs upgrade
    sv.newVar = convertOldData(sv.oldVar)
    sv.oldVar = nil
end

well that too...
like haggen and merlight said you don't have to change the version of the saved variables when you update your addon.
but i was under the impression you knew this already and had different needs. Maybe a bit more details on what you're up to ?

btw if you need to generate different files for your versions you may want to look at how Master Merchant does
I suppose he creates fake addons with just a save vars then he probably make their content global to use them in the main addon. Never used MM can't tell for sure. But if it is to extract data for your site, can be something to check too.

[cyxui]

thanks for all the ideas guys