Object API Basics

When you publish an Object, Liferay automatically generates REST APIs for it. These APIs differ for Company and Site scoped Objects, but they all use the c/[pluralobjectlabel] naming pattern (e.g., c/timeoffrequests). You can use these APIs to create, access, update, and remove Object entries.

Note

Liferay DXP 2024.Q4+ The Objects framework supports External Reference Codes (ERCs) to give you a way to identify external resources across systems.

In particular, the Objects Framework uses ERCs to link attachments to object entries, enabling consistent references across environments. When object entries are imported, their attachments are recognized automatically if present, or placeholders are created for later resolution. Additionally, for attachments uploaded directly by users and hidden from Documents and Media, the content can be included in exported data in Base64 format to facilitate availability upon import.

Here you’ll use cURL commands to perform basic CRUD operations for a custom Object. Before proceeding, set up a new Liferay DXP/Portal 7.4 instance and prepare the provided tutorial code.

Tip

For a complete list of APIs generated for both Site and Company objects, see Object’s Headless Framework Integration. You can view and test custom object APIs via the Liferay API Explorer at [server]:[port]/o/api (e.g., localhost:8080/o/api). They appear under REST Applications.

Setting Up a Liferay Instance

Start a new Liferay instance by running

docker run -it -m 8g -p 8080:8080 liferay/portal:7.4.3.120-ga120

Sign in to Liferay at http://localhost:8080. Use the email address [e-mail] and the password test. When prompted, change the password to learn.

Then, follow these steps to create a basic Object for this tutorial:

1. Open the Global Menu (), go to the Control Panel tab, and click Objects.

2. Click the Add button () and enter these values:

   Field	Value
   Label	Able
   Plural Label	Ables
   Name	Able

3. Select the new Object draft, go to the Fields tab, and add a single text field:

   Label	Field Name	Type	Required
   Name	name	Text	✔

4. Go to the Details tab and click Publish.

   Important

   For this tutorial, you must use the above values.

Publishing an Object creates and activates a new application for receiving and storing data. You can now access it via Headless APIs.

Preparing the Sample Code

Run the following commands to download and unzip the provided sample code:

curl https://resources.learn.liferay.com/dxp/latest/en/building-applications/objects/understanding-object-integrations/using-custom-object-apis/liferay-v1s4.zip -O

unzip liferay-v1s4.zip

These scripts include the following APIs:

HTTP Method	HTTP Endpoint	Description
GET	/	Returns a complete list of object entries in a Liferay instance; results can be paginated, filtered, searched, and sorted
POST	/	Creates a new object entry using the details provided in the API call
DELETE	/{objectNameId}	Deletes the specified object entry and returns a 204 if the operation succeeds
GET	/{objectNameId}	Returns details for the specified object entry
PUT	/{objectNameId}	Replaces the specified object entry’s details with those provided in the API call
GET	/{objectNameId}/permissions	Returns details for the specified object entry permissions
PUT	/{objectNameId}/permissions	Replaces the specified Object entry permission details with those provided in the API call

Calling the Custom Object’s APIs

1. After downloading the sample code, navigate to the curl folder in the liferay-v1s4 project.

   cd liferay-v1s4/curl
   

2. Execute Able_POST_ToCompany. This creates three entries.

   ./Able_POST_ToCompany.sh
   

   The terminal displays the complete schema for the newly created entries. Copy the first entry’s ID for use with the following methods.

   {
     "id" : 41969,
     ...
     "name" : "Able 1"
   }
   
   {
     "id" : 41971,
     ...
     "name" : "Able 2"
   }
   
   {
     "id" : 41973,
     ...
     "name" : "Able 3"
   }
   

3. Execute Ables_GET_FromCompany. This returns a list of the Object’s entries.

   ./Ables_GET_FromCompany.sh
   

4. Execute Able_PUT_ById with the first entry’s ID as a parameter. This replaces the details of the specified entry with the details provided in the API call.

   ./Able_PUT_ById.sh {entry-id}
   

   {
     "id" : 41969,
     ...
     "name" : "Able One"
   }
   

5. Execute Able_DELETE_ById with the same ID as its parameter. This deletes the specified entry.

   ./Able_DELETE_ById.sh {entry-id}
   

6. Execute Able_GET_ById with the same ID as its parameter. This returns the details for the specified entry if it exists.

   ./Able_GET_ById.sh {entry-id}
   

   Since you deleted the entry in the preceding step, it returns the following message.

   {
   	"status": "NOT_FOUND",
   	"title": "No ObjectEntry exists with the primary key 41969"
   }
   

Examining the Sample cURL Scripts

The following are examples of the tutorial’s cURL commands.

Able_POST_ToCompany.sh

curl \
	"http://localhost:8080/o/c/ables/" \
	--data-raw '
		{
			"name": "Able 1"
		}' \
	--header "Content-Type: application/json" \
	--request "POST" \
	--user "[e-mail]:learn"

curl \
	"http://localhost:8080/o/c/ables/" \
	--data-raw '
		{
			"name": "Able 2"
		}' \
	--header "Content-Type: application/json" \
	--request "POST" \
	--user "[e-mail]:learn"

curl \
	"http://localhost:8080/o/c/ables/" \
	--data-raw '
		{
			"name": "Able 3"
		}' \
	--header "Content-Type: application/json" \
	--request "POST" \
	--user "[e-mail]:learn"

Able_PUT_ById.sh

curl \
	"http://localhost:8080/o/c/ables/${1}" \
	--data-raw '
		{
			"name": "Able One"
		}' \
	--header "Content-Type: application/json" \
	--request "PUT" \
	--user "[e-mail]:learn"

Managing Object Permissions

Use the object APIs to read and update permissions for object entries. See Objects Application Permissions for more information.

1. Execute Able_GET_Permissions to retrieve a list of object entry permissions.

   ./Able_GET_Permissions.sh {entry-id}
   

   This example returns permissions for all roles. To retrieve permissions for a specific role, use the roleNames query parameter.

   curl \
      "http://localhost:8080/o/c/ables/${1}/permissions?roleNames=Site%20Member" \
      --user "[e-mail]:learn"
   

   In this example, the only role is Owner, and its permissions are: Delete, Permissions, Update, and View.

   {
      "actions": {
         "get": {
            "method": "GET",
            "href": "http://localhost:8080/o/c/ables/41969/permissions"
         },
         "replace": {
            "method": "PUT",
            "href": "http://localhost:8080/o/c/ables/41969/permissions"
         }
      },
      "facets": [],
      "items": [
         {
            "actionIds": [
            "DELETE",
            "PERMISSIONS",
            "UPDATE",
            "VIEW"
            ],
            "roleName": "Owner"
         }
      ],
      "lastPage": 1,
      "page": 1,
      "pageSize": 1,
      "totalCount": 1
   }
   

2. Execute Able_PUT_Permissions with the entry ID as a parameter to replace the entry’s details with those provided in the API call.

   ./Able_PUT_Permissions.sh {entry-id}
   

   The Update permission was removed from the Owner role.

   {
      "actions": {
         "get": {
            "method": "GET",
            "href": "http://localhost:8080/o/c/ables/41969/permissions"
         },
         "replace": {
            "method": "PUT",
            "href": "http://localhost:8080/o/c/ables/41969/permissions"
         }
      },
      "facets": [],
      "items": [
         {
            "actionIds": [
            "DELETE",
            "PERMISSIONS",
            "VIEW"
            ],
            "roleName": "Owner"
         }
      ],
      "lastPage": 1,
      "page": 1,
      "pageSize": 1,
      "totalCount": 1
   }
   

Managing Object Tags and Categories

You can use the Object APIs to read, set, and update tags and categories for object entries that have categorization enabled. See Tags and Categories for more information.

Tags are represented by the keywords property. You can set or update tags by adding a keywords array to the body of any POST, PUT, or PATCH request.

"keywords" : [
   "tag1", "tag2", "tag3"
]

After making a GET request for an object entry, you can read its tags in the same keywords array.

You can set and update categories for an object entry by adding the taxonomyCategoryIds array to any POST, PUT, or PATCH request.

"taxonomyCategoryIds" : [
   1234, 5678
]

Note

You must have an existing vocabulary of categories to assign categories to an object entry. See Defining Categories and Vocabularies for Content for more information.

After making a GET request for an object entry, you can read its categories in the taxonomyCategoryBriefs array, which contains the taxonomyCategoryId and taxonomyCategoryName for each assigned category.

"taxonomyCategoryBriefs": [
   {
      "taxonomyCategoryId": 1234,
      "taxonomyCategoryName": "Category A"
   },
   {
      "taxonomyCategoryId": 5678,
      "taxonomyCategoryName": "Category B"
   }
]

You can filter object entries by keywords and taxonomyCategoryIds following the rules described in API Query Parameters. Example filter strings may look like these:

• keywords/any(k:k in ('tag1','tag2')) retrieves all object entries tagged with tag1 or tag2.

• taxonomyCategoryIds/any(k:k in (1234,5678)) retrieves all entries linked to the category with ID 1234 or 5678.

You can sort object entries by fields from related objects using the syntax described in API Query Parameters. Example sorting strings may look like these:

• sort=relatedRelationship/fieldName:asc sorts the entries based on a field from a directly related object in ascending order.

• sort=relatedRelationship1/relatedRelationship1/fieldName:desc sorts the entries based on a field from a nested related object in descending order.

Using the nestedFields Parameter to Retrieve Additional Details

Some information is embedded in the object’s API response as a nested field.

Parameter Value	Description
nestedFields=[fieldName].fileBase64	Return the Base64 encoding of an attachment field.
nestedFields=[fieldName].folder	Return the folder where the Base64 encoded attachment is stored.
nestedFields=auditEvents	When entry history is enabled, return the audit events for the entry.
nestedFields=[firstObjectRelationship],[secondObjectRelationship]	Return related object entries.
nestedFields=profileURL	Return the profile URL of the entry creator user.
nestedFields=permissions	Return the roles and permissions for an entry. Available in Liferay DXP 2024.Q4+/Portal 7.4 GA129+

For example, calling the endpoint http://localhost:8080/o/c/ables/41969?nestedFields=permissions returns the permissions element in the API response:

"permissions" : [ {
    "actionIds" : [ "DELETE", "PERMISSIONS", "UPDATE", "VIEW" ],
    "roleName" : "Owner"
  } ],

Related Topics

• Using Batch APIs
• Using nestedFields to Query Related Entries
• Using Aggregation Terms with REST APIs