LR 5 functions, methods, and properties not in LR 4 docs

[John R Ellis]

While we're waiting for the SDK docs, I scanned for functions, methods, and properties not documented in the LR 4 SDK.  Here's what I found:

LrCatalog

Methods:

assertHasReadAccess

buildSmartPreviews (array of LrPhoto)

createPublishService

createVirtualCopies

getPhotoByLocalId

withReadAccessDo

Properties:

allPhotos

hasCatalogAccess

hasReadAccess

hasWriteAccess

path

targetPhoto

targetPhotos

LrCollection

Methods:

getSearchDescription

LrController

nextPhoto

previousPhoto

showBezel

showGrid

showLoupe

startSlideshow

stopSlideshow

triggerCapture

LrDialogs

closeFloatingDialogsForPlugin

presentFloatingDialog

presentWebViewDialog

showBezel (string message, [number fadeDelay])

showStringsDialog

LrDigest

HMAC

MD4

MD5

SHA1

SHA256

SHA384

SHA512

LrLogger

Methods:

configure

restoreConfiguration

saveConfiguration

wrapMethodWithTrace

wrapMethodsWithTrace

Properties:

_actions

_name

_savedConfigurations

will_debug

will_error

will_info

will_trace

will_warn

LrPhoto

Methods:

applyDevelopSnapshot

buildSmartPreview

deleteDevelopSnapshot

deleteSmartPreview

getDevelopSnapshots

locationIsPrivate

readMetadata

requestJpegThumbnail

saveMetadata

withSettingsForPluginDo

Properties:

countStackInFolderMembers

countVirtualCopies

isInStackInFolder

isVirtualCopy

localIdentifier

masterPhoto

path

stackInFolderIsCollapsed

stackInFolderMembers

stackPositionInFolder

uuid

virtualCopies

LrPhotoPictureView

makePhotoPictureView

LrPlugin

nativeFunction

LrPublishService

delete

getAllRemoteIds

promptEditDialog

LrPublishedCollection

Methods:

getSearchDescription

publishSelected

setSearchDescription

LrPublishedCollectionSet

Methods:

delete

LrPublishedPhoto

Methods:

getDevelopSettingsDigest

getMetadataDigest

LrTableUtils

debugDumpTable

LrUUID

generateUUID

LrView

Methods:

path_control

square_button

LrXml

xmlElementToSimpleTable

I didn't examine the classes LrExportContext, LrExportRendition, LrExportSession, LrExportSettings, LrFilterContext, LrVideoExportPreset, LrWebViewFactory.

[areohbee]

That would open some doors .

~R.

[jarnoh]

Direct native calls would need some more boilerplate (for pointers, callbacks).  Of course it could be some kind of lua library loader, but I wouldn't count on that either.  It would be easier to enable standard lua native libraries, if Adobe really wanted to support native code.

Perhaps it is a way to call Lightroom internal functions from a plugin?

Jarno

[John R Ellis]

Maybe it's some kind of LR-specific method for loading a Lua extension module. 

Perhaps it is a way to call Lightroom internal functions from a plugin?

Perhaps, but structurally it would be a little curious to locate it as a method of LrPlugin, rather than, say, LrApplication.

However, there is only one occurrence of the string "nativeFunction" in all the Windows files, so it's not used by other parts of LR (e.g. by the tethering plugins).  Perhaps it's not fully implemented.

[jarnoh]

I figured out how to use LrPlugin.nativeFunction to instantiate LuaSocket:

local LrApplication = import "LrApplication"

local msg = LrApplication.activeCatalog():getPath()

local luasocket = _PLUGIN:nativeFunction("luaopen_socket_core")

local core = luasocket()

local socket = core.udp()

socket:sendto(msg, '224.0.0.1', 7777)

socket:close()

(This will send a UDP multicast packet, which can be received on OSX with netcat utility: nc -u -l 7777)

LuaSocket is used in socket.lrmodule, and I found out that it is just plain lua dynamic library by running:

nm ./Contents/PlugIns/socket.lrmodule/Contents/MacOS/socket

If anyone figures out how to load your own Lua extensions from installable plugins, I'm interested

[areohbee]

Woah - this could open some doors (of course Adobe may shut them next rev) - thanks for posting Jarno.

How did you figure out the parameter to pass?

~R.

[jarnoh]

Like I said, I noticed that socket.lrmodule had actually binary with standard LuaSocket exports, and I just tried it... At first, I tried passing a filename, but since there was no file access (I used dtrace to investigate), I figured it must be something else

[jarnoh]

Hmm, actually the same code doesn't work on my other laptop...  maybe there is something in one of my installed plugins that allows loading socket library?

[areohbee]

Anybody have a clue about 'showStringsDialog'?

[John R Ellis]

It appears to display a dialog with a scrollable list of strings:

LrFunctionContext.callWithContext ("test", function (context)
    LrDialogs.showStringsDialog {
        title = "Test Strings Dialog",
        strings = {"line 1", "line 2", "line 3"},
        cancelVerb = "Stop!"}
    end)

May be unfinished (and thus undocumented) -- the "title" and "cancelVerb" parameters are ignored.

[areohbee]

Thanks John.

It would be great if it was possible to have different fonts etc. for different strings.

I mean, in the simplest case, one can accomplish the same thing (pretty much) via a scrolled_view of a static_text view.

R

[areohbee]

photo:deleteDevelopSnapshot - used to work, but doesn't anymore (granted, it was never documented).

To be clear: @Lr5.3RC, the function still exists, executes, and says it worked, but no snapshots are actually deleted.

In original Lr5 version(s), beta and 5.0 anyway, the function worked, if Lr in develop module (not library module).

[areohbee]

Differences in master vs. virtual copy, snapshot-wise:

local masterPhoto = virtualCopy:getRawMetadata( 'masterPhoto' )

local snaps = masterPhoto:getDevelopSnapshots() -- gets master and virtual copy snapshots

virtualCopy:getDevelopSnapshots() -- NEVER works.

virtualCopy:deleteDevelopSnapshot( snap[1].id_global ) -- NEVER works.

masterPhoto:deleteDevelopSnapshot( snap[1].id_global ) -- always works in develop module (do not use snapshotID, which only sometimes works).

virtualCopy:createDevelopSnapshot( name ) -- works in develop module, but always creates a new snapshot (even if name already exists).

virtualCopy:createDevelopSnapshot( name, true ) -- ditto, so pre-delete in separate with-do func to re-create/update.

~R.

[areohbee]

Just noticed these methods never made it into SDK 5 doc:

* photo:saveMetadata

* photo:readMetadata

Subject to certain caveats, these methods do seem to work, and I'm using them in released plugins.

Anybody else have any experience/problems with them?

Thanks,

Rob

[Guest]

Hi,

I was trying to get HMAC working for my Lightroom plugin but there was no luck

I coould not find any reference to HMAC functions.

There is only MD5 which is given is SDK

local LrMD5 = import 'LrMD5' -- assign namespace to local variable

local digest = LrMD5.digest( 'some string' ) -- call "digest()" function in namespace

http://wwwimages.adobe.com/content/dam/Adobe/en/devnet/photoshoplightroom/pdfs/lr5/lightroom-sdk-gui...

Does anybody know how to use the HMAC functions?

Thanks

[John R Ellis]

A little poking around suggests how to use LrDigest:

d = LrDigest.SHA256.digest ("Hello world")

d => "64ec88ca00b268e5ba1a35678a1b5316d212f4f366b2477232534a8aeca37f3c"

x = LrDigest.SHA256.init ()

x:update ("Hello ")

x:update ("world")

d = x:digest ()

d => "64ec88ca00b268e5ba1a35678a1b5316d212f4f366b2477232534a8aeca37f3c"

[Guest]

Hi john,

I really appreciate the quick response and I have been struggling with this for a few days. Your example above works perfectly.

This is what I did

local sha = import 'LrDigest'

d = sha.SHA256.digest ("Hello world")

My requirement is to do HMAC

if you do this in PHP you do like this

$genarated_hmac = hash_hmac("sha256",'string input','private key');

I tried this in my Lua plugin file but it crashed the plugin

This is what I did

local sha = import 'LrDigest'

d2 = sha.HMAC.digest ('SHA256', 'test1','test2')

I was shooting in the dark as there was no reference I could use.

Please help me if you can.

Thanks heaps again

[John R Ellis]

I didn't know what HMAC is, so I looked it up at Wikipedia, hoping to find some clues about how to use LrDigest.HMAC.  But I didn't make any progress.  It would seem that you need to specify a hash algorithm to HMAC, e.g. SHA256 or MD5, as well as a key. In Lua, it would be more likely that you pass an actual function, e.g. LrDigest.MD5.digest, rather than a string like "MD5".  But I couldn't figure out the magic sequence.  Sorry...

[Guest]

Hi John,

Thank you for trying. Appreciate it

Cheers