shmoulův blog

In last article I wrote about defining custom actions in Alfresco, in this one i want to continue with simple custom dialog triggered by this action.

So, like actions, dialogs are defined in web-client-config-custom.xml too. Definition is simple:

Name is name of the dialog, referenced by action tag (<action>dialog:createSession</action>) in action definition. Page is a .jsp page with some content and managed-bean is an managed bean 🙂 defined in faces-config-beans.xml. So, lets add some bean to the session scope:

Now we need to create cz.shmoula.CreateSessionDialog class, which extends the BaseDialogBean:

This bean implements two buttons (see Dialog Framework wiki): OK button action and visibility (ie isDisabled) of OK button, in this case it is not disabled, so it is possible to click it and ends this dialog without any intervention to system ;-).

The Retezec variable is set by bean definition to some funny string, so after creating a .jsp page and packing together all this stuff do following: In case of click on space_browse_menu it compares name of that space and if it equals with "Archivace" string, it displays "Create session" action link. After click on this link a custom dialog is opened, as you can see on image below.

.jsp page is very simple too, it doesn't need no headers due to viewing inside of Alfresco UI:

My second try was to create some custom action in some menu or bar and to view a simple dialog in Alfresco UI triggered by this action. There are topics covering this theme in Alfresco wiki too (see Custom Action UI and Dialog Framework) for detailed informations. But i wanted to create a simple and working example to see if it really works :-).

So, lets start with some action ;-). Actions are defined in web-client-config-custom.xml configuration file like this:

Items are self explaining, i hope :-). Action is to create dialog, which is defined in dialogs section with name createSession and evaluator is class which implements ActionEvaluator and indicates that this action is viewed or not. In my CreateSessionEvaluator i have just a simple condition.

Id attribute of action-group tag specifies a place in which is this action (a link) viewed, in my example it is space_browse_menu, which is the context menu of space object. Action groups are defined in web-client-config-actions.xml. Examples of some action groups are at following pictures:

space_browse_menu action group

1 – add_content_menu, 2 – browse_actions_menu

An action link is viewed at first image – "Create session". If evaluator is specified, action is viewed just in case of true evaluation. My simple evaluator is following:

It just compares space name (in case of space_browse_menu action group) with some string, nothing more :-). So, if they correspond, "Create session" link is displayed.

There are many wiki pages at Alfresco dev sites, but no working simple excercises at all. At these days i'm playing with this CMS/DMS, so i'll try to collect some remarks about actions i'm doing, maybe it'll be helpful for someone. So, i'm experimenting with Content Metadata Extracters with intention to create some kind of Video Extracter (to save bitrate, resolution, codec… to metadata with that object).

There is a simple wiki page describing that problem, so if you want to know some background, you have to start there. If you dont (or if you prefer very simple way), let's continue. So, what Content Metadata Extracters (CME) are? Imagine following simple situation: you have repository with some multimedia document, let's say mp3 files. Every mp3 file has a header with some informations (id3), for example artist, album, music style, etc. And you want to your document system to create all needed metadata automaticaly, when user uploads his mp3 file. This is work of CME. In my following example I'm not going to extract data from anywhere to keep things simple, but there is also a source of MP3 Metadata Extracter and many more, all inside of the Alfresco SDK.

I'm going to try to "how this stuff works part by part", so i'm going to create an "empty extractor" which just creates some metadata. So, first thing to do is to add my own bean to content-services-context.xml. In Wiki there is a way through editing a custom-metadata-extrators-context.xml controller, but this way doesn't work for me, so i added my definition right into content-services-context.xml:

So, id is identificator of created bean and class is my class in my package extending AbstractMappingMetadataExtracter. I chose name of ASDMetadataExtracter due to retaining of name convention of *MetadataExtrater and ASD due to my personaly liked phrase "asdfghj…" :-). And parent will automaticaly register this bean with metadataExtracterRegistry to handle mimetypes declared in my "Extractor".

Then i have to create some properties file with defined namespace prefixes and mappings on them. Alfresco for content model uses a namespace http://www.alfresco.org/model/content/1.0 and for lucidity there is a prefix cm binded with that. So my own ASDMetadataExtracter.properties file looks like this:

And last thing to do is to create a class, which fills in those metadata. I uploaded whole code to pastebin, so you can browse it online, its really simple, it has just 45 lines of code!!! But some snipets:

…

private static final String KEY_POKUS = "pokus"; // definitions of metadata names, binded with properties

… MimetypeMap.MIMETYPE_TEXT_PLAIN … // i'm using this "transformer" for text/plain mime

…

putRawValue(KEY_POKUS, Long.toString(size), rawProperties); // assigning of value to metadata

…

// TempFileProvider routines are provided just for testing purposes 😉

// Files uploaded (opened) with these routines are temporary saved in <tomcat>tempAlfresco*

So, that's all, folks :-). And what does it do? After upload of document of type text/plain it fills metadata binded. Now i'm going to solve how to view them, modify them and make a sorts based on them.