Tags API

Manage the shared tag hierarchy with com_tags. Assign tags to content through the owning component API.

See the introduction for authentication, request formats and error handling.

Routes

Paths are relative to /api/index.php. Enable the corresponding Web Services plugin.

Methods	Path	Controller tasks
GET, POST	/v1/tags	tags.displayList, tags.add
GET, PATCH, DELETE	/v1/tags/{id}	tags.displayItem, tags.edit, tags.delete

Collection GET lists records; item GET reads one; POST creates; PATCH updates; DELETE removes an eligible record. Some records must first be trashed. Consult individual operation responses for exceptions.

Forms and data

Relevant forms and extension parameter manifests are:

• Tag form (com_tags)

Joomla selects additional parameter fields according to the extension, client or field type. The OpenAPI specification includes these core parameter variants.

Field	JSON type or role	Meaning
title	string	Required tag title.
parent_id	parent selector	Parent in the hierarchy; confirm the root and intended parent.
alias, description	string	URL alias and description.
published, access	integer or numeric string	Publication state and viewing access level.
language	string	Content language tag or *.
images, params, metadata	object	Images, display options and metadata.

Creating a tag and assigning it to content are separate operations. Assign article tags through the article tags array of definition IDs. Joomla maintains tree columns: do not copy lft, rgt or level into a write. Parent selector types can differ from SQL types; use the request schema for the chosen operation.

Write a flat JSON object with these form fields. Do not wrap it in JSON:API data.attributes. Read-only response attributes are not a write template.

Backend server-side requests

This creates an unpublished tag at the top level (parent_id 1, the root). The API does not apply the form defaults: a new tag needs parent_id, description (may be empty) and language. Use a unique alias and verify the resulting hierarchy.

Joomla HTTPFactory

Use this request in a Joomla component, plugin or console command. Set the API URL, token and record values for the target site. Keep the token in your integration's secret store. HTTP and JSON errors throw exceptions for the calling extension to handle.

<?php
declare(strict_types=1);

use Joomla\Http\HttpFactory;
use Joomla\Uri\Uri;

$siteUrl = 'https://example.org';
$token = 'REPLACE_WITH_YOUR_API_TOKEN';
$headers = [
    'Accept' => 'application/vnd.api+json',
    'Content-Type' => 'application/json',
    'X-Joomla-Token' => $token,
];

$payload = [
    'title' => 'API tag',
    'alias' => 'api-tag',
    'parent_id' => 1,
    'description' => '',
    'published' => 0,
    'language' => '*',
];

$uri = (new Uri($siteUrl))
    ->setPath('/api/index.php/v1/tags');
$http = (new HttpFactory())->getHttp(['follow_location' => false]);
$response = $http->post(
    $uri,
    json_encode($payload, JSON_THROW_ON_ERROR), $headers,
    30
);

$status = $response->getStatusCode();
$body = (string) $response->getBody();

if ($status < 200 || $status >= 300) {
    throw new \RuntimeException('HTTP ' . $status . ': ' . $body);
}

$document = json_decode($body, true, 512, JSON_THROW_ON_ERROR);

if (!empty($document['errors'])) {
    throw new \RuntimeException(json_encode($document['errors'], JSON_THROW_ON_ERROR));
}

if (isset($document['success']) && $document['success'] === false) {
    throw new \RuntimeException('The API action reported failure.');
}

echo json_encode($document, JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR), PHP_EOL;

curl

This complete POSIX shell example requires curl 7.76 or later. On Windows, use a compatible shell such as Git Bash or WSL.

API_BASE='https://example.org/api/index.php/v1'
TOKEN='REPLACE_WITH_YOUR_API_TOKEN'

curl --silent --show-error --fail-with-body --include --globoff \
  --request POST \
  --url "$API_BASE/tags" \
  --header 'Accept: application/vnd.api+json' \
  --header 'X-Joomla-Token: '"$TOKEN" \
  --header 'Content-Type: application/json' \
  --data-binary @- <<'JSON'
{
  "title": "API tag",
  "alias": "api-tag",
  "parent_id": 1,
  "description": "",
  "published": 0,
  "language": "*"
}
JSON

Server-side successful response

HTTP 200 OK, with Content-Type: application/vnd.api+json. The response excerpt below shows the resource structure. Responses can also contain relationships, links and metadata. IDs and values depend on the site.

{
  "data": {
    "type": "tags",
    "id": "42",
    "attributes": {
      "title": "API tag",
      "alias": "api-tag",
      "published": 0
    }
  }
}

Read GET /tags/{id}. After assignment, read the owner and compare its tag relationships.

Frontend browser requests

These examples read tags with GET /tags. Calling the API from the browser still uses administrator models and ACL. Follow the browser setup and authentication guidance, including loading Joomla's core script for Joomla.request. Replace the site origin and API path, then enter the signed-in operator's personal API token when prompted. Keep shared integration tokens on the server.

Joomla.request

(async () => {
    const token = window.prompt('Enter your personal Joomla API token');

    if (!token) {
        throw new Error('An API token is required.');
    }

    const url = new URL('https://example.org');
    url.pathname = '/api/index.php/v1/tags';
    url.search = new URLSearchParams({
        "page[offset]": "0",
        "page[limit]": "20"
    }).toString();

    let xhr;

    try {
        xhr = await Joomla.request({
            url: url.toString(),
            method: 'GET',
            headers: {
                Accept: 'application/vnd.api+json',
                'X-Joomla-Token': token,
            },
            promise: true,
            onBefore(request) {
                request.timeout = 30000;
            },
        });
    } catch (error) {
        // Joomla.request rejects statuses other than 200, including 204.
        if (!(error instanceof XMLHttpRequest)) {
            throw error;
        }

        xhr = error;
    }

    if (xhr.status < 200 || xhr.status >= 300) {
        throw new Error(`HTTP ${xhr.status}: ${xhr.responseText || xhr.statusText}`);
    }

    const text = xhr.responseText;

    const document = text.trim() ? JSON.parse(text) : null;

    if (document?.errors && Object.keys(document.errors).length > 0) {
        throw new Error(JSON.stringify(document.errors));
    }

    if (document?.success === false) {
        throw new Error(document.message || 'The API action reported failure.');
    }

    console.log(document);
    return document;
})();

Native fetch()

(async () => {
    const token = window.prompt('Enter your personal Joomla API token');

    if (!token) {
        throw new Error('An API token is required.');
    }

    const url = new URL('https://example.org');
    url.pathname = '/api/index.php/v1/tags';
    url.search = new URLSearchParams({
        "page[offset]": "0",
        "page[limit]": "20"
    }).toString();

    const controller = new AbortController();
    const timeout = window.setTimeout(() => controller.abort(), 30000);
    let response;
    let text;

    try {
        response = await fetch(url, {
            method: 'GET',
            headers: {
                Accept: 'application/vnd.api+json',
                'X-Joomla-Token': token,
            },
            credentials: 'omit',
            redirect: 'error',
            signal: controller.signal,
        });
        text = await response.text();
    } finally {
        window.clearTimeout(timeout);
    }

    if (!response.ok) {
        throw new Error(`HTTP ${response.status}: ${text || response.statusText}`);
    }

    const document = text.trim() ? JSON.parse(text) : null;

    if (document?.errors && Object.keys(document.errors).length > 0) {
        throw new Error(JSON.stringify(document.errors));
    }

    if (document?.success === false) {
        throw new Error(document.message || 'The API action reported failure.');
    }

    console.log(document);
    return document;
})();

Both examples check the HTTP status and API error fields. An empty successful body produces null; a JSON collection has an array in data.

Browser successful response

HTTP 200 OK returns a collection such as:

{
  "data": [
    {
      "type": "tags",
      "id": "42",
      "attributes": {
        "title": "API tag",
        "alias": "api-tag",
        "published": 0
      }
    }
  ]
}

This collection excerpt omits other attributes, relationships, links and metadata. An empty result has "data": [].

Errors

These responses apply to server-side and browser clients. Check both HTTP status and response body. Wording depends on the site language, plugins and server configuration. The following examples show possible error responses.

HTTP status	Possible cause
401	Authentication is absent or invalid, or API login is not allowed.
400	Title, alias or parent validation fails.
403	The user cannot manage tags.
404	The tag cannot be found.

Form validation can produce HTTP 400 Bad Request:

{
  "errors": [
    {
      "title": "Invalid field: Title"
    }
  ]
}

Authentication failure can produce HTTP 401 Unauthorized:

{
  "errors": [
    {
      "title": "Forbidden"
    }
  ]
}

After an interrupted or failed write, read the resource before retrying. Saving may have occurred before a later error.

References

• OpenAPI reference
• Complete OpenAPI specification, including com_tags schemas
• Joomla Web Services Collection for Postman