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Info
Field Type identifier: `ezimage` Validators: File size Value object: `\eZ\Publish\Core\FieldType\Image\Value` Associated Services: `ezpublish.fieldType.ezimage.variation_service`

The Image Field Type allows you to store an image file.

A variation service handles conversion of the original image into different formats and sizes through a set of preconfigured named variations: large, small, medium, black & white thumbnail, etc.

PHP API Field Type

Value object

The value property of an Image Field will return an \eZ\Publish\Core\FieldType\Image\Value object with the following properties:

Properties

Property	Type	Example	Description
`id`	string	`0/8/4/1/1480-1-eng-GB/image.png`	The image's unique identifier. Usually the path, or a part of the path. To get the full path, use `URI` property.
`alternativeText`	string	`This is a piece of text`	The alternative text, as entered in the Field's properties
`fileName`	string	`image.png`	The original image's filename, without the path
`fileSize`	int	`37931`	The original image's size, in bytes
`uri`	string	`var/ezdemo_site/storage/images/0/8/4/1/1480-1-eng-GB/image.png`	The original image's URI
`imageId`	string	`240-1480`	A special image ID, used by REST

Image Variations

Using the variation Service, variations of the original image can be obtained. Those are \eZ\Publish\SPI\Variation\Values\ImageVariation objects with the following properties:

Property	Type	Example	Description
`width`	int	`640`	The variation's width in pixels
`height`	int	`480`	The variation's height in pixels
`name`	string	`medium`	The variation's identifier
`info`	mixed		Extra info, such as EXIF data
`fileSize`	int
`mimeType`	string
`fileName`	string
`dirPath`	string
`uri`	string		The variation's uri
`lastModified`	DateTime		When the variation was last modified

Field

Type

Defintion options

The Image Field Type supports one FieldDefinition option: the maximum size for the file.

Using an Image Field

In templates

Template Rendering

When displayed using ez_render_field, an Image Field will output this type of HTML:

Code Block

language	xml
linenumbers	true

<img src="var/ezdemo_site/storage/images/0/8/4/1/1480-1-eng-GB/image_medium.png" width="844" height="430" alt="Alternative text" />

The template called by the ez_render_field accepts several parameters:

which variation must be used can be set using the alias parameter
size and height can be forced for the image, for instance to handle custom screen densities. If not specified, the variation's attributes will be used if available.

() Twig function while rendering a Image field accepts the following the parameters:

Parameter	Type	Default	Description
`alias`	`string`	`"original"`	The image variation name, must be defined in your site access `image_variations` settings. Defaults to "original", the originally uploaded image.
`width`	`int`		Optionally to specify a different width set on the image html tag then then one from image alias.
`height`	int		Optionally to specify a different height set on the image html tag then then one from image alias.
`class`	`string`		Optionally to specify a specific html class for use in custom javascript and/or css.

Example:

Code Block
{{ ez_render_field( content, 'image', { 'parameters':{ 'alias': 'imagelarge', 'width': 400, 'height': 400 } } ) }}

The raw Field can also be used if needed. Image variations for the Field's content can be obtained using the ez_image_alias Twig helper:

Code Block
{% set imageAlias = ez_image_alias( field, versionInfo, 'medium' ) %}

The variation's properties can be used to generate the required output:

Code Block
<img src="{{ asset( imageAlias.uri ) }}" width="{{ imageAlias.width }}" height="{{ imageAlias.height }}" alt="{{ field.value.alternativeText }}" />

With the REST API

Image Fields within REST are exposed by the application/vnd.ez.api.Content media-type. An Image Field will look like this:

Info

title	inputUri

From 5.2 version, new images must be input using the inputUri property from Image\Value.

The keys id and path still work, but a deprecation warning will be thrown.

Code Block

language	xml
title	Version >= 5.2
linenumbers	true

<field>
    <id>1480</id>
    <fieldDefinitionIdentifier>image</fieldDefinitionIdentifier>
    <languageCode>eng-GB</languageCode>
    <fieldValue>
        <value key="inputUri">/var/ezdemo_site/storage/images/0/8/4/1/1480-1-eng-GB/kidding.png</value>
        <value key="alternativeText"></value>
        <value key="fileName">kidding.png</value>
        <value key="fileSize">37931</value>
        <value key="imageId">240-1480</value>
        <value key="uri">/var/ezdemo_site/storage/images/0/8/4/1/1480-1-eng-GB/kidding.png</value>
        <value key="variations">
            <value key="articleimage">
                <value key="href">/api/ezp/v2/content/binary/images/240-1480/variations/articleimage</value>
            </value>
            <value key="articlethumbnail">
                <value key="href">/api/ezp/v2/content/binary/images/240-1480/variations/articlethumbnail</value>
            </value>
        </value>
    </fieldValue>
</field>

Code Block

language	xml
title	Before 5.2
linenumbers	true
collapse	true

<field>
    <id>1480</id>
    <fieldDefinitionIdentifier>image</fieldDefinitionIdentifier>
    <languageCode>eng-GB</languageCode>
    <fieldValue>
        <value key="id">var/ezdemo_site/storage/images/0/8/4/1/1480-1-eng-GB/kidding.png</value>
        <value key="path">/var/ezdemo_site/storage/images/0/8/4/1/1480-1-eng-GB/kidding.png</value>
        <value key="alternativeText"></value>
        <value key="fileName">kidding.png</value>
        <value key="fileSize">37931</value>
        <value key="imageId">240-1480</value>
        <value key="uri">/var/ezdemo_site/storage/images/0/8/4/1/1480-1-eng-GB/kidding.png</value>
        <value key="variations">
            <value key="articleimage">
                <value key="href">/api/ezp/v2/content/binary/images/240-1480/variations/articleimage</value>
            </value>
            <value key="articlethumbnail">
                <value key="href">/api/ezp/v2/content/binary/images/240-1480/variations/articlethumbnail</value>
            </value>
        </value>
    </fieldValue>
</field>

Children of the fieldValue node will list the general properties of the Field's original image (fileSize, fileName, inputUri, etc.), as well as variations. For each variation, a uri is provided. Requested through REST, this resource will generate the variation if it doesn't exist yet, and list the variation details:

Code Block

language	xml
linenumbers	true

<ContentImageVariation media-type="application/vnd.ez.api.ContentImageVariation+xml" href="/api/ezp/v2/content/binary/images/240-1480/variations/tiny">
  <uri>/var/ezdemo_site/storage/images/0/8/4/1/1480-1-eng-GB/kidding_tiny.png</uri>
  <contentType>image/png</contentType>
  <width>30</width>
  <height>30</height>
  <fileSize>1361</fileSize>
</ContentImageVariation>

From PHP code

Getting an image variation

The variation service, ezpublish.fieldType.ezimage.variation_service, can be used to generate/get variations for a Field. It expects a VersionInfo, the Image Field and the variation name, as a string (large, medium, etc.)

Code Block

language	php
type	php
linenumbers	true

$variation = $imageVariationHandler->getVariation(
    $imageField, $versionInfo, 'large'
);

echo $variation->uri;

Manipulating image content

From PHP

As for any Field Type, there are several ways to input content to a Field. For an Image, the quickest is to call setField() on the ContentStruct:

Code Block

language	php
type	php
linenumbers	true

$createStruct = $contentService->newContentCreateStruct(
    $contentTypeService->loadContentType( 'image' ),
    'eng-GB'
);

$createStruct->setField( 'image', '/tmp/image.png' );

In order to customize the Image's alternative texts, you must first get an Image\Value object, and set this property. For that, you can use the Image\Value::fromString() method that accepts the path to a local file:

Code Block

language	php
type	php
linenumbers	true

$createStruct = $contentService->newContentCreateStruct(
    $contentTypeService->loadContentType( 'image' ),
    'eng-GB'
);

$imageField = \eZ\Publish\Core\FieldType\Image\Value::fromString( '/tmp/image.png' );
$imageField->alternativeText = 'My alternative text';
$createStruct->setField( 'image', $imageField );

You can also provide a hash of Image\Value properties, either to setField(), or to the constructor:

Code Block

language	php
type	php
linenumbers	true

$imageValue = new \eZ\Publish\Core\FieldType\Image\Value(
    array(
        'id' => '/tmp/image.png',
        'fileSize' => 37931,
        'fileName' => 'image.png',
        'alternativeText' => 'My alternative text'
    )
);

$createStruct->setField( 'image', $imageValue );

From REST

The REST API expects Field values to be provided in a hash-like structure. Those keys are identical to those expected by the Image\Value constructor: fileName, alternativeText. In addition, image data can be provided using the data property, with the image's content encoded as base64.

Creating an image Field

Code Block

language	xml
type	xml
linenumbers	true

<?xml version="1.0" encoding="UTF-8"?>
<ContentCreate>
    <!-- [...metadata...] -->

    <fields>
        <field>
            <id>247</id>
            <fieldDefinitionIdentifier>image</fieldDefinitionIdentifier>
            <languageCode>eng-GB</languageCode>
            <fieldValue>
                <value key="fileName">rest-rocks.jpg</value>
                <value key="alternativeText">HTTP</value>
                <value key="data"><![CDATA[/9j/4AAQSkZJRgABAQEAZABkAAD/2wBDAAIBAQIBAQICAgICAgICAwUDAwMDAwYEBAMFBwYHBwcG
BwcICQsJCAgKCAcHCg0KCgsMDAwMBwkODw0MDgsMDAz/2[...]</value>
            </fieldValue>
        </field>
    </fields>
</ContentCreate>

Updating an image Field

Updating an Image Field requires that you re-send existing data. This can be done by re-using the Field obtained via REST, removing the variations key, and updating alternativeText, fileName or data. If you do not want to change the image itself, do not provide the data key.

Code Block

language	xml
type	xml
linenumbers	true

<?xml version="1.0" encoding="UTF-8"?>
<VersionUpdate>
    <fields>
        <field>
            <id>247</id>
            <fieldDefinitionIdentifier>image</fieldDefinitionIdentifier>
            <languageCode>eng-GB</languageCode>
            <fieldValue>
                <value key="id">media/images/507-1-eng-GB/Existing-image.png</value>
                <value key="alternativeText">Updated alternative text</value>
                <value key="fileName">Updated-filename.png</value>
			</fieldValue>
        </field>
    </fields>
</VersionUpdate>

Naming

Each storage engine determines how image files are named.

Legacy Storage Engine naming

Images are stored within the following directory structure:

<varDir>/<StorageDir>/<ImagesStorageDir>/<FieIdId[-1]>/<FieIdId[-2]>/<FieIdId[-3]>/<FieIdId[-4]>/<FieldId>-<VersionNumber>-<LanguageCode>/

With the following values:

VarDir = var (default)
StorageDir = storage (default)
ImagesStorageDir = images (default)
FieldId = 1480
VersionNumber = 1
LanguageCode = eng-GB

Images will be stored to web/var/ezdemo_site/storage/images/0/8/4/1/1480-1-eng-GB.

Info
Using the field ID digits in reverse order as the folder structure maximizes sharding of files through multiple folders on the filesystem.

Within this folder, images will be named like the uploaded file, suffixed with an underscore and the variation name:

MyImage.png
MyImage_large.png
MyImage_rss.png

General

Developer documentation

Versions Compared

Old Version 3

New Version Current

Key

PHP API Field Type

Value object

Properties

Image Variations

Field

Defintion options

Using an Image Field

Template Rendering

With the REST API

From PHP code

Getting an image variation

Manipulating image content

From PHP

From REST

Creating an image Field

Updating an image Field

Naming

Legacy Storage Engine naming