Tags Subdomain

This module (isis-module-tags) provides the ability to add multiple tags (or labels) to any domain entity.

For example, an Email entity could be associated with a priority tag of 'urgent', 'normal' or 'low', and could also have a category tag of 'work', 'family', 'friends'.

The idea is to allow a user to label an entity by offering a choice of other existing tags associated with other entities of the same type and also tag type. That is, the combination of the entity type (eg com.mycompany.myapp.Email) and the tag type (eg priority) creates a named set of available tags (eg 'urgent', 'normal', low').

As well as listing existing tags, new tags can of course also be created, and existing tags updated or removed.


The module’s functionality can be explored by running the quickstart with example usage using the org.incode.domainapp.example.app.modules.ExampleDomDomTagAppManifest.

A home page is displayed when the app is run:

010 install fixtures

The remaining screenshots below do demonstrate the functionality of this module, but are out of date in that they are taken from the original isisaddons/incodehq module (prior to being amalgamated into the incode-platform).

One of the demo objects created is "Bip". The class of this entity is not of interest, what is of interest is that it has two properties, brand and sector, that correspond to `Tag`s:

020 example entity with two tag categories

Update tag

Using the action, can update tag. The Tags service provides a list of available tag (names) for this entity type and tag name ("brand"):

040 available tags for brand

The tag can then be saved:

050 updated brand

If the tag is updated once more, note that the original tag ("Coca Cola") is no longer listed. This is because there are no other entities that have this label:

060 previous brand removed

New tags

New tags can also be created. Enter the tag name:

080 new brand specified

The tag is saved:

090 new brand saved

... and is available as a choice for this or any other entity of the same type:

100 new brand available as choice

How to configure/use


Update your classpath by adding this dependency in your dom project’s pom.xml:


Check for later releases by searching [Maven Central Repo](http://search.maven.org/#search|ga|1|isis-module-tags-dom).

For instructions on how to use the latest -SNAPSHOT, see the contributors guide.


In the AppManifest, update its getModules() method, eg:

public List<Class<?>> getModules() {
    return Arrays.asList(


The main functionality is exposed through the Tags domain service, which provides two methods:

public class Tags {

    public List<String> choices(                                        (1)
        final Object taggedObject, final String tagKey) { ... }

    public Tag tagFor(                                                  (2)
            final Object taggedObject,
            final Tag existingTag,
            final String tagKey, final String tagValue) { ... }

<1>`choices(…​)` returns a list of tags as strings for the object being tagged (eg Email) and for the tag key (eg priority) <2> tagFor(…​) will create/update a tag for the object being tagged (eg Email), the tag key (eg priority) and the tag value (eg 'urgent'). The existing tag (if any) is passed in so that it can be removed if the tag value is left as null.

Known issues

None known at this time.


Maven can report modules dependencies using:

mvn dependency:list -o -pl modules/dom/tags/impl -D excludeTransitive=true

which, excluding the Apache Isis modules, returns no direct compile/runtime dependencies.

The module does use icons from icons8.