Category: Alfresco API

Cool things you can do in Alfresco with cmis:item support

allyoursysbaseI’ve been taking a look at the newly-added support for cmis:item in Alfresco. As a refresher for those who may not be familiar, cmis:item is a new object type added to the CMIS 1.1 specification. Alfresco added support for CMIS 1.1 in 4.2 but did not immediately add support for cmis:item, which is optional, according to the spec. Now cmis:item support is available in Alfresco in the cloud as well as the nightly builds of 4.3.a Community Edition.

So what is cmis:item?

We’ve all written content-centric applications that have included objects that don’t have a content stream. You might use one to store some configuration information, for example, or maybe you have some other object that doesn’t naturally include a file that needs to be managed as part of it. There are a few approaches to this in Alfresco:

  1. Create your custom type as a child of sys:base (or cm:cmobject if you don’t mind your objects being subject to the file name constraint)
  2. Create your custom type as child of cm:content and simply do not set a content stream
  3. Ignore the content model altogether and use the attribute service

I’m not going to cover the third option in this post. If you want to learn more about the attribute service you should take a look at the Tech Talk Live we did in April.

The second option is fine, but then you’ve got objects with content properties that will never be set. Your objects look like they want to be documents, but they really aren’t because you don’t expect them to ever have a file as part of the object. Not the end of the world, but it’s kind of lazy and potentially confusing to developers that come after you.

The first option is what most people go with, but it has a drawback. Instances of types that do not extend from cm:content or cm:folder are invisible to CMIS 1.0. Not only are those objects invisible to CMIS 1.0 but relationships that point to such objects are also invisible. Depending on how much you use CMIS in your application this could be a fairly severe limitation.

Thankfully, CMIS 1.1 addresses the issue with a new object type called cmis:item. It’s made precisely for this purpose.

What can I do with it out-of-the-box?

Even if your custom content model doesn’t need a “content-less object” you can still benefit from cmis:item support. Let me walk you through my five favorite object types that you can now work with via cmis:item support in CMIS 1.1 that were not previously available: Category, Person, Group, Rating, and Rule. I tested everything I’m showing you here using Alfresco 4.3.a Community Edition, Nightly Build (4/27/2014, (r68092-b4954) schema 7003) and Apache Chemistry OpenCMIS Workbench 0.11.0.


Man, if I had a bitcoin for every person I’ve seen asking how to get the categories of a document via CMIS, I’d have a garage full of Teslas. With cmis:item support, it’s easy. Here’s how you get a list of every category in the system with a CMIS Query Language (CQL) query:

SELECT * FROM cm:category

That returns a list of cm:category objects that represent each category in the system. Note that this is a flat list. In Alfresco, categories are hierarchical. I’m not sure what the plan to address that is, to be honest.

Now suppose you have an object and you want to know the categories that have been assigned. Here is some Groovy code that does that:

(Can’t see the code? Click here)

Categories live in a property called “cm:categories”. It’s a multi-value field that contains the Alfresco node references for each category that has been assigned to a document. Once you get that list you can iterate over them and fetch the cm:category object to figure out the category’s human-readable name. That’s pretty cool and wasn’t possible before CMIS 1.1 support.

How about assigning existing categories to documents? Sure, no problem. Here’s how.

(Can’t see the code? Click here)

This is a little Groovy function that takes a full path to a document and the name of a category. Obviously it depends on your categories being uniquely-named.

First, it finds the category by name using CQL and snags its Alfresco node reference.

Next, it checks to see if the cm:generalclassifiable aspect has already been added to the document and adds it if it has not.

Finally, it gets the current list of categories from the cm:categories property and adds the new category’s node reference to it.

I started to look at creating new categories with CMIS, but it isn’t immediately obvious how that would work due to the hierarchical nature of categories. The only parent-child association supported by CMIS is the one implied by folder-document relationship. I’ll ask around and see if there’s a trick.

That’s it for categories. Let’s look at Person objects next.


Here’s another frequently-asked how-to: How do I query users through CMIS? Before cmis:item support you couldn’t do it, but now you can. For example, here is how you can use CQL to find a list of the Person objects in Alfresco:

SELECT * FROM cm:person

You can qualify it further based on properties of cm:person. For example, maybe I want all users who’s first name starts with “Te” and who work for an organization that starts with “Green”. That query looks like:

SELECT * FROM cm:person where cm:firstName like 'Te%' and cm:organization like 'Green%'

Suppose you wanted to find every Alfresco Person object that has a city starting with “Dallas” and you want to set their postal code to “75070”. Ignoring cities named “Dallas” that aren’t in Texas (like Dallas, Georgia) or the fact that there are multiple zip codes in Dallas, Texas, the code would look like this:

(Can’t see the code? Click here)

That’s it for Person objects. Let’s look at Group objects.


Similar to querying for Person objects, cmis:item support gives you the ability to query for groups–all you have to know is that groups are implemented as instances of cm:authorityContainer. Here’s the query:

SELECT * FROM cm:authorityContainer

Unfortunately, it doesn’t seem possible to use CMIS to actually add or remove members to or from the group. Maybe that will change at some point.


It’s easy to query for ratings:

SELECT * FROM cm:rating

But it’s hard to do anything useful with those objects because, at least in this nightly release, you can’t follow the relationships from or two a rating. As a sidenote, you can get the count and total for a specific node’s ratings by getting the value of the cm:likesRatingSchemeCount and cm:likesRatingSchemeTotal properties respectively. But that’s not related to cmis:item support.


Rules are a powerful feature in Alfresco that help you automate document handling. Here’s how to use a query to get a list of rules in your repository:

SELECT * FROM rule:rule

Rules are so handy you might end up with a bunch of them. What if you wanted to find all of the rules that matched a certain criteria (title, for example) so that you could enable them and tell them to run on sub-folders? Here is a little Groovy that does that:

(Can’t see the code? Click here)

First the code uses a join to find the rule based on a title. The property that holds a rule’s title is defined in an aspect and that requires a join when writing CQL.

Then the code simply iterates over the result set and updates the rule:applyToChildren and rule:disabled properties. You could also set the rule’s type, description, and whether or not it runs asynchronously. It does not appear to be possible to change the actions or the filter criteria for a rule through CMIS at this time.

What about custom types?

Custom types? Sure, no problem. Suppose I have a type called sc:client that extends sys:base and has two properties, sc:clientName and sc:clientId. Alfresco automatically makes that type accessible via CMIS. It’s easy to create a new instance and set the value of those two properties. Here’s the groovy code to do it:

(Can’t see the code? Click here)

Did you notice I created the object in a folder? In Alfresco, everything lives in a folder, even things that aren’t documents. In CMIS parlance, you would say that Alfresco does not support “unfiled” objects.

The custom object can be queried as you would expect, including where clauses that use the custom property values, like this:

SELECT * FROM sc:client where sc:clientId = '56789'

In CMIS 1.0 you could not use CMIS to work with associations (“relationships”) between objects that did not inherit from either cm:content (cmis:document) or cm:folder (cmis:folder). In CMIS 1.1 that changed. You can create relationships between documents and folders and items. Unfortunately, in the latest nightly build this does not appear to be implemented. Hopefully that goes in soon!


The new cmis:item type in CMIS 1.1 is a nice addition to the specification that is useful when you are working with objects that are not documents and do not have a content stream. I showed you some out-of-the-box types you can work with via cmis:item but you can also leverage cmis:item with your custom types as well.

Support for cmis:item requires CMIS 1.1 and either Alfresco in the cloud or a recent nightly build of Alfresco 4.3.

CMIS example: Uploading multiple files to a CMIS repository

In my previous post on CMIS, I introduced the Content Management Interoperability Services (CMIS) specification and the Apache Chemistry project. You learned that CMIS gives you a language-neutral, vendor-independent way to perform CRUD functions against any CMIS-compliant server using a standard API. I showed a simple CMIS query being executed from a Groovy script running in the OpenCMIS Workbench.

Now I’d like to get a little more detailed and show a simple use case: I’ll use the OpenCMIS client library for Java to upload some files from my local machine to a CMIS repository. In my case, that repository is Alfresco 4.2.c Community Edition running locally, but this code should work with any CMIS-compliant server from vendors like IBM, EMC, Microsoft, Nuxeo, and so on. I’ll include the relevant snippets, but if you want to follow along, the full source code for this example lives here. I use that example to show the same code working against Alfresco in the cloud and Alfresco on-premise. If you are running against on-premise only or some other CMIS server, it has a few dependencies that won’t be relevant to you. is a runnable Java class. The main method simply calls doExample(). That method grabs a session, gets a handle to the destination folder for the files on the local machine, and then, for each file in the local machine’s directory, it creates a hashmap of metadata values, then uploads each file and its associated metadata to the repository. Let’s look at each of these pieces in turn.

Get a Session

The first thing you need is a session. I have a getCmisSession() method that knows how to get one, and it looks like this:

SessionFactory factory = SessionFactoryImpl.newInstance();
Map parameter = new HashMap();

// connection settings
parameter.put(SessionParameter.ATOMPUB_URL, ATOMPUB_URL);
parameter.put(SessionParameter.BINDING_TYPE, BindingType.ATOMPUB.value());
parameter.put(SessionParameter.AUTH_HTTP_BASIC, "true");
parameter.put(SessionParameter.USER, USER_NAME);
parameter.put(SessionParameter.PASSWORD, PASSWORD);

List repositories = factory.getRepositories(parameter);

return repositories.get(0).createSession();

As you can see, establishing a session is as simple as providing the username, password, binding, and service URL. The binding is the protocol we’re going to use to talk to the server. In CMIS 1.0, usually the best choice is the Atom Pub binding because it is faster than the Web Services binding, the only other alternative. CMIS 1.1 adds a browser binding that is based on HTML forms and JSON but I won’t cover that here.

The other parameter that gets set is the service URL. This is server-specific. For Alfresco 4.x or higher, the CMIS 1.0 Atom Pub URL is http://localhost:8080/alfresco/cmisatom.

The last thing the method does is return a session for a specific repository. CMIS servers can serve more than one repository. In Alfresco’s case, there is only ever one, so it is safe to return the first one in the list.

Get the Target Folder

Okay, we’ve got a session with the CMIS server’s repository. The repository is a hierarchical tree of objects (folders and documents) similar to a local file system. The class is configured with a parent folder path and the name of a new folder that should be created in that parent folder. So the first thing we need to do is get a reference to the parent folder. My example getParentFolder() method just grabs the folder by path, like this:

Folder folder = (Folder) cmisSession.getObjectByPath(FOLDER_PATH);
return folder;

Now, given the parent folder and the name of a new folder, the createFolder() method attempts to create the new folder to hold our files:

Folder subFolder = null;
try {
  subFolder = (Folder) cmisSession.getObjectByPath(parentFolder.getPath() + "/" + folderName);
  System.out.println("Folder already existed!");
} catch (CmisObjectNotFoundException onfe) {
  Map props = new HashMap();
  props.put("cmis:objectTypeId",  "cmis:folder");
  props.put("cmis:name", folderName);
  subFolder = parentFolder.createFolder(props);
  String subFolderId = subFolder.getId();
  System.out.println("Created new folder: " + subFolderId);
return subFolder;

The folder is either going to already exist, in which case we’ll just grab it and return it, or it will need to be created. We can test the existence of the folder by trying to fetch it by path, and if it throws a CmisObjectNotFoundException, we’ll create it.

Look at the Map that is getting set up to hold the properties of the folder. The minimum required properties that need to be passed in are the type of folder to be created (“cmis:folder”) and the name of the folder to create. You might choose to extend your server’s content model with your own folder types. In this example, the out-of-the-box “cmis:folder” type is fine.

Set Up the Properties For Each New Document

Just like when the folder was created, every file we upload to the repository will have its own set of metadata. To make it interesting, though, we’ll provide more than just the type of document we want to create and the name of the document. In my example, I’m using a content model we created for the CMIS & Apache Chemistry in Action book. It contains several types. One of which is called “cmisbook:image”. The image type has attributes you’d expect that would be part of an image, like height, width, focal length, camera make, ISO speed, etc. In fact, if you use the OpenCMIS Workbench, you can inspect the type definition for cmisbook:image. Here’s a screenshot (click to enlarge):

OpenCMIS Workbench, Type Inspector

Two of the properties I’m going to work with in this example are the latitude and longitude. Alfresco will automatically extract metadata like this when you add files to the repository. In fact, Alfresco already has a “geographic aspect” out-of-the-box that can be used to extract and store lat and long. But we wanted this content model to work with any CMIS repository and not all repositories support aspects (CMIS 1.1 call these “secondary types”) so the content model used in the book defines lat and long on the cmisbook:image type.

Because not all repositories know how to extract metadata, we’re going to use Apache Tika to do it in our client app.

The getProperties() method does this work. It returns a Map of properties that consists of the type of the object we want to create (“cmisbook:image”), the name of the object (the file name being uploaded), and the latitude and longitude. Here’s what that code looks like:

Map props = new HashMap();

String fileName = file.getName();
System.out.println("File: " + fileName);
InputStream stream = new FileInputStream(file);
try {
  Metadata metadata = new Metadata();
  ContentHandler handler = new DefaultHandler();
  Parser parser = new JpegParser();
  ParseContext context = new ParseContext();

  metadata.set(Metadata.CONTENT_TYPE, FILE_TYPE);

  parser.parse(stream, handler, metadata, context);
  String lat = metadata.get("geo:lat");
  String lon = metadata.get("geo:long");

  // create a map of properties
  props.put("cmis:objectTypeId",  objectTypeId);
  props.put("cmis:name", fileName);
  if (lat != null && lon != null) {
    System.out.println("LAT:" + lat);
    System.out.println("LON:" + lon);
    props.put("cmisbook:gpsLatitude", BigDecimal.valueOf(Float.parseFloat(lat)));
    props.put("cmisbook:gpsLongitude", BigDecimal.valueOf(Float.parseFloat(lon)));
} catch (TikaException te) {
  System.out.println("Caught tika exception, skipping");
} catch (SAXException se) {
  System.out.println("Caught SAXException, skipping");
} finally {
  if (stream != null) {
return props;

Now we have everything we need to upload the file to the repository: a session, the target folder, and a map of properties for each object being uploaded. All that’s left to do is upload the file.

Upload the File

The first thing the createDocument() method does is to make sure that we have a Map with the minimal set of metadata, which is the object type and the name. It’s conceivable that things didn’t go well in the getProperties() method, and if that is the case, this bit of code makes sure everything is in place:

String fileName = file.getName();

// create a map of properties if one wasn't passed in
if (props == null) {
  props = new HashMap<String, Object>();

// Add the object type ID if it wasn't already
if (props.get("cmis:objectTypeId") == null) {
  props.put("cmis:objectTypeId",  "cmis:document");

// Add the name if it wasn't already
if (props.get("cmis:name") == null) {
  props.put("cmis:name", fileName);

Next we use the file and the object factory on the CMIS session to set up a ContentStream object:

ContentStream contentStream = cmisSession.getObjectFactory().
    new FileInputStream(file)

And finally, the file can be uploaded.

Document document = null;
try {
  document = parentFolder.createDocument(props, contentStream, null);
  System.out.println("Created new document: " + document.getId());
} catch (CmisContentAlreadyExistsException ccaee) {
  document = (Document) cmisSession.getObjectByPath(parentFolder.getPath() + "/" + fileName);
  System.out.println("Document already exists: " + fileName);
return document;

Similar to the folder creating logic earlier, it could be that the document already exists, so we use the same find-or-create pattern here.

When I run this locally using a folder that contains five pics I snapped in Berlin, the output looks like this:

Created new folder: workspace://SpacesStore/2f576635-5058-4053-9a61-dad68939fdd2
File: augustiner.jpg
Created new document: workspace://SpacesStore/b19755e1-74a2-4c1e-9eb5-a5bfd2c0ebd7;1.0
File: berlin_cathedral.jpg
Created new document: workspace://SpacesStore/34aa7b80-9f09-4c07-a040-9aee94debf80;1.0
File: brandenburg.jpg
Created new document: workspace://SpacesStore/6c02f8f6-accc-4997-be5c-601bc7131247;1.0
File: gendarmenmarkt.jpg
Created new document: workspace://SpacesStore/44ff28e7-782a-46c3-b388-453fd8495472;1.0
File: old_museum.jpg
Created new document: workspace://SpacesStore/03a85605-4a66-4f94-b423-82502efbca4a;1.0

Now Run Against Another Vendor’s Repo

What’s kind of cool, and what I think really demonstrates the great thing about CMIS, is that you can run this class against any CMIS repository, virtually unchanged. To demonstrate this, I’ll fire up the Apache Chemistry InMemory Repository we ship with the source code that accompanies the book because it is already configured with a custom content model that includes “cmisbook:image”. As the name suggests, this repository is a reference CMIS server available from Apache Chemistry that runs entirely in-memory.

To run the class against the Apache Chemistry InMemory Repository, we have to change the service URL and the content type ID, like this:

//public static final String CONTENT_TYPE = "D:cmisbook:image";
public static final String CONTENT_TYPE = "cmisbook:image";

//public static final String ATOMPUB_URL = ALFRESCO_API_URL + "alfresco/cmisatom";
public static final String ATOMPUB_URL = ALFRESCO_API_URL + "inmemory/atom";

And when I run the class, my photos get uploaded to a completely different repository implementation.

That’s It!

That’s a simple example, I know, but it illustrates fetching objects, creating new objects, including those of custom types, setting metadata, and handling exceptions all through an industry-standard API. There is a lot more to CMIS and OpenCMIS, in particular. I invite you to learn more by diving in to CMIS & Apache Chemistry in Action!

Announcement: Apache Chemistry cmislib 0.5.1 now available

The Apache Chemistry project is pleased to announce that cmislib 0.5.1 is now available (home, docs). Developers can use cmislib to write Python applications against any CMIS-compliant repository such as Alfresco, SharePoint, Nuxeo, and FileNet. You can download the client library from the Apache Chemistry cmislib home page or use Setup Tools to install the library quickly and easily.

This release features support for renditions, so if your repository supports things like thumbnails, you can retrieve a list of those for a given object. The new release also supports passing in arbitrary HTTP headers. That is one way to enable authentication scenarios beyond basic authentication such as OAuth2, which is the authentication mechanism Alfresco in the Cloud uses.

If you are brand new to CMIS, here are a few links to get you started:

In addition, I’ve been working on an Apache Chemistry and CMIS in Action book with Jay Brown and Florian Mueller. The book is available now through Manning’s early-access program.