Changelog

JSON schema for creating a content type

Contentstack understands JSON data. If you want to create a content type through API or a JSON file (instead of through the user interface), you need to create a JSON file that contains the content type schema and use the "Import content type" option in the product or send the schema as the body in the API request.

Each field added in the content type has its schema. Let's look at them in detail in the following section.

JSON Schema of Fields

Here's the JSON schema of all the fields and how you can use them in the content type JSON file.

Title

The Title field is the entry title and will have a unique value, i.e., entries cannot have the same title.

The schema of the Title field is given as follows:

{
    "display_name": "Title",
    "uid": "title",
    "data_type": "text",
    "mandatory": true,
    "unique": true,
    "field_metadata": {
        "_default": true
    },
    "multiple": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

To mark this field as non-unique, set the unique parameter to false.

URL

The URL field allows you to enter a URL of the entry.

The schema of the URL field is as follows:

{
    "display_name": "URL",
    "uid": "url",
    "data_type": "text",
    "mandatory": true,
    "field_metadata": {
        "_default": true
    },
    "multiple": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

Single line textbox

The Single Line Textbox field supports only plain text and is used to enter some short text.

The schema of the Single line textbox field is given as follows:

{
    "data_type": "text",
    "display_name": "Single line textbox",
    "uid": "single_line",
    "field_metadata": {
        "description": "",
        "default_value": ""
    },
    "format": "",
    "error_messages": {
        "format": ""
    },
    "multiple": false,
    "mandatory": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section. This field possesses a couple of parameters that you can add as follows:

format: This parameter takes a regex that you can use to validate the value of a field.
error_messages: This parameter is the error message that will be displayed if a field value is not validated. You can set a format for it as well.

Multi line textbox

The Multi Line Textbox field accepts multi-line arbitrary text and enters a large chunk of data.

The schema of the Multi line textbox field is given as follows:

{
    "data_type": "text",
    "display_name": "Multi line textbox",
    "uid": "multi_line",
    "field_metadata": {
        "description": "",
        "default_value": "",
        "multiline": true
    },
    "format": "",
    "error_messages": {
        "format": ""
    },
    "multiple": false,
    "mandatory": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section. This parameter possesses a couple of parameters, such as format and error_messages, common to the “Single Line Textbox” field.

HTML-based Rich text editor

The HTML-based Rich Text Editor field accepts a variety of data types, such as text, images, and videos and allows you to format the content entered in the field.

The schema of the HTML-based Rich Text Editor field is given as follows:

{
    "data_type": "text",
    "display_name": "HTML Rich text editor",
    "uid": "html_rich_text_editor",
    "field_metadata": {
        "allow_rich_text": true,
        "description": "",
        "multiline": false,
        "rich_text_type": "advanced",
        "version": 3
    },
    "multiple": false,
    "mandatory": false,
    "unique": false
}

The parameters in the JSON body above are explained in the "Field Parameters" section.

Within the field_metadata parameter, you can provide the keys given below:

allow_rich_text: This key determines whether the editor will support rich text and is set to true by default for Rich Text Editors.
description: This key allows you to provide the content for the Rich text editor field.
multiline: This key provides multiline capabilities to the Rich text editor.
rich_text_type: This key lets you enable the basic, custom, or advanced editor to enter your content.
options: If you choose the Custom editor, then the options key lets you specify the formatting options you prefer for your RTE toolbar, e.g., "options": ["h3", "blockquote", "sup"]
version: This key determines whether you are using the older version of the Rich Text Editor or the latest version. The value of 1 denotes an older version of the editor, while 3 denotes the latest version of the editor.

The following table displays the various formatting options that can be added to your customized HTML-based RTE toolbar:

Formatting Options	Description
html	Allows you to view and edit your content in HTML format.
undo	Allows you to undo your last action. You can undo more than one action.
redo	Allows you to redo an undone action. You can redo more than one undone action.
blockquote	Allows you to set apart quoted text from the surrounding content.
pre	Allows you to apply code block formatting to a specific code snippet.
h1 to h6	Allows you to apply a specific heading style to a piece of text. You can apply Heading 1, 2, 3, 4, 5, or 6 depending upon the heading level.
h1 to h6	Allows you to apply a specific heading style to a piece of text. You can apply Heading 1, 2, 3, 4, 5, or 6 depending upon the heading level.
bold	Allows you to highlight certain text within the editor in bold.
underline	Allows you to underline specific text within the editor.
italic	Allows you to italicize specific text within the editor.
deleted	Allows you to strikethrough certain words in the editor.
sup	Allows you to format certain text in the editor as superscript.
sub	Allows you to format certain text in the editor as subscript.
lists	Allows you to structure a list of related items within the text as numbered or bulleted lists.
alignment	Allows you to change text alignment inside the editor. By default, Contentstack aligns text to the left. You can either center the text, align it to the right, or justify it.
video	Allows you to embed a YouTube or Vimeo video within the rich text editor content.
imagemanager	Allows you to insert images within the rich text editor content.
table	Allows you to add a table to the rich text editor content.
link	Allows you to add hyperlinks to certain text within the editor content.
properties	Allows you to point a piece of text to a certain class or ID defined within the stylesheet used for formatting the editor. The class or ID attribute you specify applies a specific style to the concerned text.
reference_to	Allows you to embed entries and assets within an entry.

JSON Rich Text Editor

The JSON Rich Text Editor field accepts a variety of data types, such as text, images, and videos and allows you to format the content entered in the field.

The schema for the JSON RTE field within a content type is as follows:

{
  "data_type":"json",
  "display_name":"JSON RTE",
  "uid":"json_rte",
  "field_metadata":{
    "allow_json_rte":true,
    "rich_text_type":"advanced",
    "description":"",
    "default_value":""
  },
  "reference_to":[
    "content_type_uid"
  ],
  "non_localizable":false,
  "multiple":false,
  "mandatory":false,
  "unique":false
}

Note: The JSON Rich Text Editor will have the same formatting options as the HTML-based RTE that can be added to your customized RTE toolbar. The only difference would be that the JSON RTE will not have the HTML source code viewer.

Additional Resource:You can also migrate content from your HTML-based RTE to the new JSON RTE using our CLI. Read more about our migration guide.

Markdown

The Markdown field accepts text in markdown format which is an easy-to-read text that is marked with certain tags or formatting instructions.

The schema of the Markdown field is given as follows:

{
    "data_type": "text",
    "display_name": "Markdown",
    "uid": "markdown",
    "field_metadata": {
        "description": "",
        "markdown": true
    },
    "multiple": false,
    "mandatory": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

To enable the field to accept markdown content, you need to set a key, "markdown": true, in the field_metadata parameter.

Select

The Select field allows users to choose one or more options from a set of predefined choices that can be displayed in the form of radio buttons, checkboxes, or dropdown options.

The schema of the Select field is given as follows:

{
    "data_type": "text",
    "display_name": "Select",
    "display_type": "dropdown",
    "enum": {
        "advanced": false,
        "choices": [{
            "value": "1"
        }, {
            "value": "2"
        }, {
            "value": "3"
        }]
    },
    "multiple": true,
    "uid": "select",
    "field_metadata": {
        "description": "",
        "default_value": ""
    },
    "mandatory": false,
    "unique": false
}

When the Key-value pair option is toggled on, the advanced parameter in the Select field schema is set to true and the schema displays the key and value added by the user.

The schema of such a Select field is given as follows:

{
    "data_type":"text",
    "display_name":"Select",
    "display_type":"dropdown",
    "enum":{
        "advanced":true,
        "choices":[
            {
                "key":"New York",
                "value":"NY"
            },
            {
                "key":"India",
                "value":"IN"
            },
            {
                "key":"Australia",
                "value":"AUS"
            }
        ]
    },
    "multiple":true,
    "uid":"select",
    "field_metadata":{
        "description":"",
        "default_value":""
    },
    "mandatory":false,
    "unique":false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

Additionally, you need to set the parameters given below:

display_type: This parameter allows you to assign a display type either in the form of radio button, checkboxes, or dropdown.
enum: This parameter allows you to provide the choice for the ‘Select’ field.
advanced: This parameter when set to true allows you to provide choices for the 'Select' field in key-value pairs.

Modular Blocks

The Modular Blocks field allows content managers to dynamically create and modify components of a page or app on the go.

The schema of a Modular Blocks field consisting of a Single Line Textbox and a Rich Text Editor is given as follows:

{
    "data_type": "blocks",
    "display_name": "Modular Blocks",
    "abstract": "Create content dynamically",
    "blocks": [{
        "title": "Block",
        "uid": "block",
        "autoEdit": true,
        "schema": [{
                "data_type": "text",
                "display_name": "Single line textbox",
                "abstract": "Name, title, email address, any short text",
                "uid": "single_line",
                "field_metadata": {
                    "description": "",
                    "default_value": ""
                },
                "class": "high-lighter",
                "format": "",
                "error_messages": {
                    "format": ""
                }
            },
            {
                "data_type": "text",
                "display_name": "Rich text editor",
                "abstract": "Long text with formatting options",
                "uid": "rich_text_editor",
                "field_metadata": {
                    "allow_rich_text": true,
                    "description": "",
                    "multiline": false,
                    "rich_text_type": "advanced"
                },
                "class": "high-lighter"
            }
        ]
    }],
    "multiple": true,
    "uid": "modular_blocks",
    "field_metadata": {}
}

You can also add Global fields as blocks in a Modular Blocks field. The schema of a Modular Blocks field consisting of a Global field as a block and a normal block schema is given as follows:

{
    "data_type": "blocks",
    "display_name": "Modular Blocks",
    "abstract": "Create content dynamically",
    "blocks": [{
        "title": "Block",
        "uid": "block",
        "autoEdit": true,
        "schema": [{
                "data_type": "text",
                "display_name": "Single line textbox",
                "abstract": "Name, title, email address, any short text",
                "uid": "single_line",
                "field_metadata": {
                    "description": "",
                    "default_value": ""
                },
                "class": "high-lighter",
                "format": "",
                "error_messages": {
                    "format": ""
                }
            },
            {
                "data_type": "text",
                "display_name": "Rich text editor",
                "abstract": "Long text with formatting options",
                "uid": "rich_text_editor",
                "field_metadata": {
                    "allow_rich_text": true,
                    "description": "",
                    "multiline": false,
                    "rich_text_type": "advanced"
                },
                "class": "high-lighter"
            }
        ]
    }, {
        "title": "Block",
        "uid": "block",
        "reference_to": "global_field_uid"
    }],
    "multiple": true,
    "uid": "modular_blocks",
    "field_metadata": {}
}

You need to mention the Global field that your parent content type will refer to in the reference_to parameter.

Number

The Number field accepts numeric data where you can enter any kind of numbers such as phone number or zip code.

The schema of the Number field is given as follows:

{
    "data_type": "number",
    "display_name": "Number",
    "uid": "number",
    "field_metadata": {
        "description": "",
        "default_value": ""
    },
    "multiple": false,
    "mandatory": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

You need to enter the data_type parameter as number.

Boolean

The Boolean field accepts a true or false value.

The schema of the Boolean field is given as follows:

{
    "data_type": "boolean",
    "display_name": "Boolean",
    "uid": "boolean",
    "field_metadata": {
        "description": "",
        "default_value": ""
    },
    "multiple": false,
    "mandatory": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

You need to enter the data_type parameter as boolean.

Date

The Date field renders a calendar that allows the user to select a date and time, which is accepted in the ISO format

The schema of the Date field is given as follows:

{
    "data_type": "isodate",
    "display_name": "Date",
    "uid": "date",
    "startDate": null,
    "endDate": null,
    "field_metadata": {
        "description": "",
        "default_value": ""
    },
    "multiple": false,
    "mandatory": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

You need to enter the data_type parameter as isodate, and provide the startDate and endDate parameters if you want to display a date range.

File

The File field lets you upload or use files in your entry.

The schema of the File field is given as follows:

{
    "data_type": "file",
    "display_name": "File",
    "uid": "file",
    "extensions": [],
    "field_metadata": {
        "description": "",
        "rich_text_type": "standard"
    },
    "multiple": false,
    "mandatory": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

Set the data_type parameter as file and add the extensions parameter. Additionally, mention the "rich_text_type": "standard" key in the field_metadata parameter.

Link

The Link field accepts a valid static or relative URL and a title.

The schema of the Link field is given as follows:

{
    "data_type": "link",
    "display_name": "Link",
    "uid": "link",
    "field_metadata": {
        "description": "",
        "default_value": {
            "title": "",
            "url": ""
        }
    },
    "multiple": false,
    "mandatory": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

Set the data_type parameter as linklink, and add title and url in the default_value key within the field_metadata parameter.

Reference

The Reference field allows you to create references to entries of the same content type or other content types.

The schema of the Reference field is given as follows:

{
    "data_type": "reference",
    "display_name": "Reference",
    "reference_to": "",
    "field_metadata": {
        "ref_multiple": false
    },
    "uid": "reference",
    "mandatory": false,
    "multiple": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

You need to mention either the same content type or another content type that your parent content type will refer to in the reference_to parameter.

Group

The Group field allows you to create a group of multiple fields.

The schema of the Group field is given as follows:

{
    "data_type": "group",
    "display_name": "Group",
    "field_metadata": {},
    "schema": [{
        "data_type": "text",
        "display_name": "Single line textbox",
        "uid": "single_line",
        "field_metadata": {
            "description": "",
            "default_value": ""
        },
        "format": "",
        "error_messages": {
            "format": ""
        },
        "multiple": false,
        "mandatory": false,
        "unique": false
    }],
    "uid": "group",
    "multiple": true,
    "mandatory": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

The details of the fields that you need to add in the Group field are mentioned in the schema parameter.

Global Field

A Global field is a reusable field (or group of fields) that you can define once and reuse in any content type within your stack.

The schema of the Global field is given as follows:

{
  "data_type": "global_field",
  "display_name": "Global Field",
  "reference_to": "{{global_field_uid}}",
  "uid": "global_field",
  "mandatory": false,
  "multiple": false,
  "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

The details of the fields that have to be added in the Global field are mentioned in the schema parameters.

Taxonomy

The Taxonomy field allows users to categorize content within your stack to facilitate easy navigation, search, and retrieval of information.

The schema of the Taxonomy field is given as follows:

{
   "uid":"taxonomies",
   "taxonomies":[
      {
         "taxonomy_uid":"taxonomy_1",
         "max_terms":5,
         "mandatory":true,
         "non_localizable":false
      },
      {
         "taxonomy_uid":"taxonomy_2",
         "max_terms":10,
         "mandatory":false,
         "non_localizable":false
      }
   ],
   "multiple":true
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

Custom Field – Group Within Group

You can create a custom field by adding a Group field within another Group field.

The schema of the Group Within Group field is given as follows:

{
    "data_type": "group",
    "display_name": "Group_within_group",
    "field_metadata": {},
    "schema": [{
        "data_type": "group",
        "display_name": "Group_within_group_subgroup",
        "field_metadata": {},
        "schema": [{
            "data_type": "text",
            "display_name": "Single line textbox",
            "uid": "single_line",
            "field_metadata": {
                "description": "",
                "default_value": ""
            },
            "format": "",
            "error_messages": {
                "format": ""
            },
            "multiple": false,
            "mandatory": false,
            "unique": false
        }],
        "uid": "group_within_group_subgroup",
        "multiple": true,
        "max_instance": 2,
        "mandatory": false,
        "unique": false
    }],
    "uid": "group_within_group",
    "multiple": false,
    "mandatory": false,
    "unique": false
}

The parameters in the JSON body above are explained in the “Field Parameters” section.

The max_instance parameter lets you decide the maximum limit for your internal Group, within the main Group schema.

Custom Field - Global Field within Group Field

You can create a Custom field by adding a Global field within another Group field.

The schema of the Global field within Group field is given as follows:

{
    "data_type": "group",
    "display_name": "Group",
    "schema": [{
        "data_type": "global_field",
        "display_name": "Global",
        "reference_to": "global_field_uid",
        "field_metadata": {
            "description": ""
        },
        "uid": "global"
    }],
    "uid": "group",
    "multiple": false,
    "mandatory": false
}

Custom Field – Extensions

You can create a custom field that you can use in your content types.

The schema of the Extension field is given as follows:

{
    "display_name": "Extension",
    "uid": "text",
    "data_type": "json",
    "extension_uid": "blt002c000ce00b00000",
    "config": {
         "key": "value"
       },
    "mandatory": true,
    "field_metadata": {
        "_default": true
    },
    "multiple": false,
    "unique": false
}

Note: config JSON object key(s) cannot start with “$” or contain “.”

Field Parameters Explained

Let’s see the parameters in the schema in detail:

Parameters	Description	Supported fields
display_name	Determines the display name of a field. It is a mandatory field.	All fields
uid	Represents the unique ID of each field. It is a mandatory field.	All fields
data_type	Determines what value can be provided to the Title field.	All fields
field_metadata	Allows you to enter additional data about a field. Also, you can add additional values under ‘field_metadata’. _default: Allows you to set default fields for content types. default_value: Allows you to set a default value for a field. allow_rich_text: Determines whether the editor will support rich text, and is set to ‘true’ by default for Rich Text Editors. description: Allows you to provide the content for the Rich text editor field. multiline: Provides multi-line capabilities to the Rich text editor. rich_text_type: Lets you enable either the basic, custom, or advanced editor to enter your content. options: If you choose the Custom editor, then the options key lets you specify the formatting options you prefer for your RTE toolbar, e.g., "options": ["h3", "blockquote", "sup"] version: This key determines whether you are using the older version of the Rich Text Editor or the latest version. The value of 1 denotes that it is an older version of the editor, while 3 denotes that it is the latest version of the editor. markdown: Lets you assign a field to be a markdown by setting its value to ‘true’. placeholder: Allows you to provide a hint text about the values that need to be entered in an input field, e.g., Single Line Textbox. This text can be seen inside the field until you enter a value. instruction: Allows you to add instructions for the content managers while entering values for a field. The instructional text appears below the field. description: Allows you to provide additional information about a field. The help text appears when the user hovers on the "?" sign beside the field name.	All fields
multiple	Allows you to assign multiple values to a field. By default, this parameter is set to “false” for the Title field. For Content Types with the field marked as multiple, you need to pass the values in the array format in the request body. For example, "multi_line": ["Text1", "Text2"]	All fields
mandatory	Determines whether a field can be left without a value or not. If the mandatory parameter of a field is set to “true,” the user cannot leave this field empty.	All fields
unique	Decides whether the value entered in the field has to be unique or not.	All fields
format	Takes a regex that you can use to validate the value of a field.	Single line textbox, Multi line textbox
error_messages	Stores the error message that will be displayed if a field value is not validated. You can set a format for it as well.	Single line textbox, Multi line textbox
enum	Allows you to provide the choice for the Select field.	Select
advanced	Determines whether a select field can contain normal choices or key-value choices. Set the advanced parameter to "true" to add key-value pairs in the Select field.	Select
reference_to	Allows you to set a reference to any content type or global field.	Reference, Global fields
format	Allows you to set the schema for ‘Group’ and nested Group fields.	Group, Nested Group fields
schema	Defines the details of the fields that have to be added in the Group field.	Group, Nested Group fields
max_instance	Decides the maximum limit for your internal Group, within the main Group schema.	Nested Group fields
max_terms	Decides the maximum limit for terms allowed for a specific Taxonomy within an entry.	Taxonomy

JSON Schema of Content Type Elements

Each feature associated with a content type also has its own schema definition. Let’s understand how the schema for such features is used in the content type JSON file.

Options

The “Options” schema allows you to define specific settings for your content type. You can either mark content types as single or multiple, or define the type of your content type as webpage or content block.

The “Options” schema looks as follows:

"options": {
                "is_page": true,
                "singleton": false,
                "title": "title",
                "sub_title": [],
                "url_pattern": "/:title",
                "url_prefix": "/"
            }

Field Rules

The “Field Rules” schema allows you to set field visibility rules for your content type. You can hide or display specific fields (target fields) on the entry page based on the values specified in other fields (operand fields) of the entry.

The “Field Rules” schema looks as follows:

"field_rules": [
                {
                    "conditions": [
                        {
                            "operand_field": "author",
                            "operator": "contains",
                            "value": "Dale"
                        }
                    ],
                    "actions": [
                        {
                            "action": "hide",
                            "target_field": "description"
                        }
                    ],
                    "match_type": "all"
                }
            ]

Content Type Parameters Explained

Let’s understand the different schema parameters in detail:

Parameters	Description
_version	Specifies the number assigned to every version of a specific content type. Editing the schema of a content type, adding or removing field visibility rules, or updating the content type details automatically increments the version number of the content type by 1.
is_page	Allows you to create content types as “Webpages” or “Content Blocks”, and is set to “true” for webpages.
singleton	Marks a content type as “Single” or “Multiple”, and is set to “true” for content types with unique schemas.
url_pattern	Allows you to set a default URL pattern for all the entries of the content type, for example, “/title”.
url_prefix	Defines the path where an entry of the content type exists.
conditions	Allows you to define conditions for your field visibility rules. Under “conditions”, you can specify the following parameters: operand_field: Determine the field on which you want to set the condition. operator: Determine an operator for your condition (for e.g., Matches). value: Specify the expected value for the operand field.
actions	Allows you to define actions to be taken as per your field visibility rules. Under “actions”, you can specify the following parameters: action: Determine the action(s) to be performed when the conditions are met (for e.g., Show or Hide) target_field: Specify the field that needs to be displayed or hidden as per the condition.
match_type	Determines whether the field visibility rule should be applied when “all” or “any” of the specified conditions are met.

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Contentstack basics

Quickstart in 5 mins

Starter apps

Content Delivery APIs

Content Management APIs

How-to guides

JSON schema for creating a content type

JSON Schema of Fields

Title

URL

Single line textbox

Multi line textbox

HTML-based Rich text editor

JSON Rich Text Editor

Markdown

Select

Modular Blocks

Number

Boolean

Date

File

Link

Reference

Group

Global Field

Taxonomy

Custom Field – Group Within Group

Custom Field - Global Field within Group Field

Custom Field – Extensions

Field Parameters Explained

JSON Schema of Content Type Elements

Options

Field Rules

Content Type Parameters Explained

More articles in "Get Started with Content Types"

Import Prebuilt Content Models

Create a Content Type

Using Prebuilt Content Models

Single vs Multiple

Content Modeling

Edit a Content Type

Scenarios Where Editing a Content Type Is Unsafe

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Contentstack
basics

Quickstart
in 5 mins

Starter
apps

Content Delivery
APIs

Content
Management APIs

How-to
guides

Contentstack
basics

Quickstart
in 5 mins

Starter
apps

Content Delivery
APIs

Content
Management APIs

How-to
guides