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# Custom Fields
Each model in NetBox is represented in the database as a discrete table, and each attribute of a model exists as a column within its table. For example, sites are stored in the `dcim_site` table, which has columns named `name`, `facility`, `physical_address`, and so on. As new attributes are added to objects throughout the development of NetBox, tables are expanded to include new rows.
However, some users might want to store additional object attributes that are somewhat esoteric in nature, and that would not make sense to include in the core NetBox database schema. For instance, suppose your organization needs to associate each device with a ticket number correlating it with an internal support system record. This is certainly a legitimate use for NetBox, but it's not a common enough need to warrant including a field for _every_ NetBox installation. Instead, you can create a custom field to hold this data.
Within the database, custom fields are stored as JSON data directly alongside each object. This alleviates the need for complex queries when retrieving objects.
## Creating Custom Fields
Custom fields may be created by navigating to Customization > Custom Fields. NetBox supports many types of custom field:
* Text: Free-form text (intended for single-line use)
* Long text: Free-form of any length; supports Markdown rendering
* Integer: A whole number (positive or negative)
* Boolean: True or false
* Date: A date in ISO 8601 format (YYYY-MM-DD)
* URL: This will be presented as a link in the web UI
* JSON: Arbitrary data stored in JSON format
* Selection: A selection of one of several pre-defined custom choices
* Multiple selection: A selection field which supports the assignment of multiple values
* Object: A single NetBox object of the type defined by `object_type`
* Multiple object: One or more NetBox objects of the type defined by `object_type`
Each custom field must have a name. This should be a simple database-friendly string (e.g. `tps_report`) and may contain only alphanumeric characters and underscores. You may also assign a corresponding human-friendly label (e.g. "TPS report"); the label will be displayed on web forms. A weight is also required: Higher-weight fields will be ordered lower within a form. (The default weight is 100.) If a description is provided, it will appear beneath the field in a form.
Marking a field as required will force the user to provide a value for the field when creating a new object or when saving an existing object. A default value for the field may also be provided. Use "true" or "false" for boolean fields, or the exact value of a choice for selection fields.
A custom field must be assigned to one or more object types, or models, in NetBox. Once created, custom fields will automatically appear as part of these models in the web UI and REST API. Note that not all models support custom fields.
### Filtering
The filter logic controls how values are matched when filtering objects by the custom field. Loose filtering (the default) matches on a partial value, whereas exact matching requires a complete match of the given string to a field's value. For example, exact filtering with the string "red" will only match the exact value "red", whereas loose filtering will match on the values "red", "red-orange", or "bored". Setting the filter logic to "disabled" disables filtering by the field entirely.
### Grouping
!!! note
This feature was introduced in NetBox v3.3.
Related custom fields can be grouped together within the UI by assigning each the same group name. When at least one custom field for an object type has a group defined, it will appear under the group heading within the custom fields panel under the object view. All custom fields with the same group name will appear under that heading. (Note that the group names must match exactly, or each will appear as a separate heading.)
This parameter has no effect on the API representation of custom field data.
### Visibility
!!! note
This feature was introduced in NetBox v3.3.
When creating a custom field, there are three options for UI visibility. These control how and whether the custom field is displayed within the NetBox UI.
* **Read/write** (default): The custom field is included when viewing and editing objects.
* **Read-only**: The custom field is displayed when viewing an object, but it cannot be edited via the UI. (It will appear in the form as a read-only field.)
* **Hidden**: The custom field will never be displayed within the UI. This option is recommended for fields which are not intended for use by human users.
Note that this setting has no impact on the REST or GraphQL APIs: Custom field data will always be available via either API.
### Validation
NetBox supports limited custom validation for custom field values. Following are the types of validation enforced for each field type:
* Text: Regular expression (optional)
* Integer: Minimum and/or maximum value (optional)
* Selection: Must exactly match one of the prescribed choices
### Custom Selection Fields
Each custom selection field must have at least two choices. These are specified as a comma-separated list. Choices appear in forms in the order they are listed. Note that choice values are saved exactly as they appear, so it's best to avoid superfluous punctuation or symbols where possible.
If a default value is specified for a selection field, it must exactly match one of the provided choices. The value of a multiple selection field will always return a list, even if only one value is selected.
### Custom Object Fields
An object or multi-object custom field can be used to refer to a particular NetBox object or objects as the "value" for a custom field. These custom fields must define an `object_type`, which determines the type of object to which custom field instances point.
## Custom Fields in Templates
Several features within NetBox, such as export templates and webhooks, utilize Jinja2 templating. For convenience, objects which support custom field assignment expose custom field data through the `cf` property. This is a bit cleaner than accessing custom field data through the actual field (`custom_field_data`).
For example, a custom field named `foo123` on the Site model is accessible on an instance as `{{ site.cf.foo123 }}`.
## Custom Fields and the REST API
When retrieving an object via the REST API, all of its custom data will be included within the `custom_fields` attribute. For example, below is the partial output of a site with two custom fields defined:
```json
{
"id": 123,
"url": "http://localhost:8000/api/dcim/sites/123/",
"name": "Raleigh 42",
...
"custom_fields": {
"deployed": "2018-06-19",
"site_code": "US-NC-RAL42"
},
...
```
To set or change these values, simply include nested JSON data. For example:
```json
{
"name": "New Site",
"slug": "new-site",
"custom_fields": {
"deployed": "2019-03-24"
}
}
```

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# Custom Links
Custom links allow users to display arbitrary hyperlinks to external content within NetBox object views. These are helpful for cross-referencing related records in systems outside NetBox. For example, you might create a custom link on the device view which links to the current device in a Network Monitoring System (NMS).
Custom links are created by navigating to Customization > Custom Links. Each link is associated with a particular NetBox object type (site, device, prefix, etc.) and will be displayed on relevant views. Each link has display text and a URL, and data from the NetBox item being viewed can be included in the link using [Jinja2 template code](https://jinja2docs.readthedocs.io/en/stable/) through the variable `obj`, and custom fields through `obj.cf`.
For example, you might define a link like this:
* Text: `View NMS`
* URL: `https://nms.example.com/nodes/?name={{ obj.name }}`
When viewing a device named Router4, this link would render as:
```no-highlight
<a href="https://nms.example.com/nodes/?name=Router4">View NMS</a>
```
Custom links appear as buttons in the top right corner of the page. Numeric weighting can be used to influence the ordering of links, and each link can be enabled or disabled individually.
!!! warning
Custom links rely on user-created code to generate arbitrary HTML output, which may be dangerous. Only grant permission to create or modify custom links to trusted users.
## Context Data
The following context data is available within the template when rendering a custom link's text or URL.
| Variable | Description |
|-----------|-------------------------------------------------------------------------------------------------------------------|
| `object` | The NetBox object being displayed |
| `obj` | Same as `object`; maintained for backward compatability until NetBox v3.5 |
| `debug` | A boolean indicating whether debugging is enabled |
| `request` | The current WSGI request |
| `user` | The current user (if authenticated) |
| `perms` | The [permissions](https://docs.djangoproject.com/en/stable/topics/auth/default/#permissions) assigned to the user |
While most of the context variables listed above will have consistent attributes, the object will be an instance of the specific object being viewed when the link is rendered. Different models have different fields and properties, so you may need to some research to determine the attributes available for use within your template for a specific object type.
Checking the REST API representation of an object is generally a convenient way to determine what attributes are available. You can also reference the NetBox source code directly for a comprehensive list.
## Conditional Rendering
Only links which render with non-empty text are included on the page. You can employ conditional Jinja2 logic to control the conditions under which a link gets rendered.
For example, if you only want to display a link for active devices, you could set the link text to
```jinja2
{% if obj.status == 'active' %}View NMS{% endif %}
```
The link will not appear when viewing a device with any status other than "active."
As another example, if you wanted to show only devices belonging to a certain manufacturer, you could do something like this:
```jinja2
{% if obj.device_type.manufacturer.name == 'Cisco' %}View NMS{% endif %}
```
The link will only appear when viewing a device with a manufacturer name of "Cisco."
## Link Groups
Group names can be specified to organize links into groups. Links with the same group name will render as a dropdown menu beneath a single button bearing the name of the group.
## Table Columns
Custom links can also be included in object tables by selecting the desired links from the table configuration form. When displayed, each link will render as a hyperlink for its corresponding object. When exported (e.g. as CSV data), each link render only its URL.

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# Export Templates
NetBox allows users to define custom templates that can be used when exporting objects. To create an export template, navigate to Customization > Export Templates.
Each export template is associated with a certain type of object. For instance, if you create an export template for VLANs, your custom template will appear under the "Export" button on the VLANs list. Each export template must have a name, and may optionally designate a specific export [MIME type](https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types) and/or file extension.
Export templates must be written in [Jinja2](https://jinja.palletsprojects.com/).
!!! note
The name `table` is reserved for internal use.
!!! warning
Export templates are rendered using user-submitted code, which may pose security risks under certain conditions. Only grant permission to create or modify export templates to trusted users.
The list of objects returned from the database when rendering an export template is stored in the `queryset` variable, which you'll typically want to iterate through using a `for` loop. Object properties can be access by name. For example:
```jinja2
{% for rack in queryset %}
Rack: {{ rack.name }}
Site: {{ rack.site.name }}
Height: {{ rack.u_height }}U
{% endfor %}
```
To access custom fields of an object within a template, use the `cf` attribute. For example, `{{ obj.cf.color }}` will return the value (if any) for a custom field named `color` on `obj`.
If you need to use the config context data in an export template, you'll should use the function `get_config_context` to get all the config context data. For example:
```
{% for server in queryset %}
{% set data = server.get_config_context() %}
{{ data.syslog }}
{% endfor %}
```
The `as_attachment` attribute of an export template controls its behavior when rendered. If true, the rendered content will be returned to the user as a downloadable file. If false, it will be displayed within the browser. (This may be handy e.g. for generating HTML content.)
A MIME type and file extension can optionally be defined for each export template. The default MIME type is `text/plain`.
## REST API Integration
When it is necessary to provide authentication credentials (such as when [`LOGIN_REQUIRED`](../configuration/security.md#login_required) has been enabled), it is recommended to render export templates via the REST API. This allows the client to specify an authentication token. To render an export template via the REST API, make a `GET` request to the model's list endpoint and append the `export` parameter specifying the export template name. For example:
```
GET /api/dcim/sites/?export=MyTemplateName
```
Note that the body of the response will contain only the rendered export template content, as opposed to a JSON object or list.
## Example
Here's an example device export template that will generate a simple Nagios configuration from a list of devices.
```
{% for device in queryset %}{% if device.status and device.primary_ip %}define host{
use generic-switch
host_name {{ device.name }}
address {{ device.primary_ip.address.ip }}
}
{% endif %}{% endfor %}
```
The generated output will look something like this:
```
define host{
use generic-switch
host_name switch1
address 192.0.2.1
}
define host{
use generic-switch
host_name switch2
address 192.0.2.2
}
define host{
use generic-switch
host_name switch3
address 192.0.2.3
}
```

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# Custom Fields
Each model in NetBox is represented in the database as a discrete table, and each attribute of a model exists as a column within its table. For example, sites are stored in the `dcim_site` table, which has columns named `name`, `facility`, `physical_address`, and so on. As new attributes are added to objects throughout the development of NetBox, tables are expanded to include new rows.
## Fields
However, some users might want to store additional object attributes that are somewhat esoteric in nature, and that would not make sense to include in the core NetBox database schema. For instance, suppose your organization needs to associate each device with a ticket number correlating it with an internal support system record. This is certainly a legitimate use for NetBox, but it's not a common enough need to warrant including a field for _every_ NetBox installation. Instead, you can create a custom field to hold this data.
### Model(s)
Within the database, custom fields are stored as JSON data directly alongside each object. This alleviates the need for complex queries when retrieving objects.
Select the NetBox object type or types to which this custom field applies.
## Creating Custom Fields
### Name
Custom fields may be created by navigating to Customization > Custom Fields. NetBox supports six types of custom field:
The raw field name. This will be used in the database and API, and should consist only of alphanumeric characters and underscores. (Use the `label` field to designate a human-friendly name for the custom field.)
* Text: Free-form text (intended for single-line use)
* Long text: Free-form of any length; supports Markdown rendering
* Integer: A whole number (positive or negative)
* Boolean: True or false
* Date: A date in ISO 8601 format (YYYY-MM-DD)
* URL: This will be presented as a link in the web UI
* JSON: Arbitrary data stored in JSON format
* Selection: A selection of one of several pre-defined custom choices
* Multiple selection: A selection field which supports the assignment of multiple values
* Object: A single NetBox object of the type defined by `object_type`
* Multiple object: One or more NetBox objects of the type defined by `object_type`
### Label
Each custom field must have a name. This should be a simple database-friendly string (e.g. `tps_report`) and may contain only alphanumeric characters and underscores. You may also assign a corresponding human-friendly label (e.g. "TPS report"); the label will be displayed on web forms. A weight is also required: Higher-weight fields will be ordered lower within a form. (The default weight is 100.) If a description is provided, it will appear beneath the field in a form.
An optional human-friendly name for the custom field. If not defined, the field's `name` attribute will be used.
Marking a field as required will force the user to provide a value for the field when creating a new object or when saving an existing object. A default value for the field may also be provided. Use "true" or "false" for boolean fields, or the exact value of a choice for selection fields.
### Group Name
A custom field must be assigned to one or more object types, or models, in NetBox. Once created, custom fields will automatically appear as part of these models in the web UI and REST API. Note that not all models support custom fields.
If this custom field should be grouped with others, specify the name of the group here. Custom fields with no group defined will be ordered only by weight and name.
### Filtering
### Type
The filter logic controls how values are matched when filtering objects by the custom field. Loose filtering (the default) matches on a partial value, whereas exact matching requires a complete match of the given string to a field's value. For example, exact filtering with the string "red" will only match the exact value "red", whereas loose filtering will match on the values "red", "red-orange", or "bored". Setting the filter logic to "disabled" disables filtering by the field entirely.
The type of data this field holds. This must be one of the following:
### Grouping
| Type | Description |
|--------------------|--------------------------------------------------------------------|
| Text | Free-form text (intended for single-line use) |
| Long text | Free-form of any length; supports Markdown rendering |
| Integer | A whole number (positive or negative) |
| Boolean | True or false |
| Date | A date in ISO 8601 format (YYYY-MM-DD) |
| URL | This will be presented as a link in the web UI |
| JSON | Arbitrary data stored in JSON format |
| Selection | A selection of one of several pre-defined custom choices |
| Multiple selection | A selection field which supports the assignment of multiple values |
| Object | A single NetBox object of the type defined by `object_type` |
| Multiple object | One or more NetBox objects of the type defined by `object_type` |
!!! note
This feature was introduced in NetBox v3.3.
### Object Type
Related custom fields can be grouped together within the UI by assigning each the same group name. When at least one custom field for an object type has a group defined, it will appear under the group heading within the custom fields panel under the object view. All custom fields with the same group name will appear under that heading. (Note that the group names must match exactly, or each will appear as a separate heading.)
For object and multiple-object fields only. Designates the type of NetBox object being referenced.
This parameter has no effect on the API representation of custom field data.
### Weight
### Visibility
A numeric weight used to override alphabetic ordering of fields by name. Custom fields with a lower weight will be listed before those with a higher weight. (Note that weight applies within the context of a custom field group, if defined.)
!!! note
This feature was introduced in NetBox v3.3.
### Required
When creating a custom field, there are three options for UI visibility. These control how and whether the custom field is displayed within the NetBox UI.
If checked, this custom field must be populated with a valid value for the object to pass validation.
* **Read/write** (default): The custom field is included when viewing and editing objects.
* **Read-only**: The custom field is displayed when viewing an object, but it cannot be edited via the UI. (It will appear in the form as a read-only field.)
* **Hidden**: The custom field will never be displayed within the UI. This option is recommended for fields which are not intended for use by human users.
### Description
Note that this setting has no impact on the REST or GraphQL APIs: Custom field data will always be available via either API.
A brief description of the field's purpose (optional).
### Validation
### Filter Logic
NetBox supports limited custom validation for custom field values. Following are the types of validation enforced for each field type:
Defines how filters are evaluated against custom field values.
* Text: Regular expression (optional)
* Integer: Minimum and/or maximum value (optional)
* Selection: Must exactly match one of the prescribed choices
| Option | Description |
|----------|-------------------------------------|
| Disabled | Filtering disabled |
| Loose | Match any occurrence of the value |
| Exact | Match only the complete field value |
### Custom Selection Fields
### UI Visibility
Each custom selection field must have at least two choices. These are specified as a comma-separated list. Choices appear in forms in the order they are listed. Note that choice values are saved exactly as they appear, so it's best to avoid superfluous punctuation or symbols where possible.
Controls how and whether the custom field is displayed within the NetBox user interface.
If a default value is specified for a selection field, it must exactly match one of the provided choices. The value of a multiple selection field will always return a list, even if only one value is selected.
| Option | Description |
|------------|--------------------------------------|
| Read/write | Display and permit editing (default) |
| Read-only | Display field but disallow editing |
| Hidden | Do not display field in the UI |
### Custom Object Fields
### Default
An object or multi-object custom field can be used to refer to a particular NetBox object or objects as the "value" for a custom field. These custom fields must define an `object_type`, which determines the type of object to which custom field instances point.
The default value to populate for the custom field when creating new objects (optional). This value must be expressed as JSON. If this is a choice or multi-choice field, this must be one of the available choices.
### Choices
## Custom Fields in Templates
For choice and multi-choice custom fields only. A comma-delimited list of the available choices.
Several features within NetBox, such as export templates and webhooks, utilize Jinja2 templating. For convenience, objects which support custom field assignment expose custom field data through the `cf` property. This is a bit cleaner than accessing custom field data through the actual field (`custom_field_data`).
### Minimum Value
For example, a custom field named `foo123` on the Site model is accessible on an instance as `{{ site.cf.foo123 }}`.
For numeric custom fields only. The minimum valid value (optional).
## Custom Fields and the REST API
### Maximum Value
When retrieving an object via the REST API, all of its custom data will be included within the `custom_fields` attribute. For example, below is the partial output of a site with two custom fields defined:
For numeric custom fields only. The maximum valid value (optional).
```json
{
"id": 123,
"url": "http://localhost:8000/api/dcim/sites/123/",
"name": "Raleigh 42",
...
"custom_fields": {
"deployed": "2018-06-19",
"site_code": "US-NC-RAL42"
},
...
```
### Validation Regex
To set or change these values, simply include nested JSON data. For example:
```json
{
"name": "New Site",
"slug": "new-site",
"custom_fields": {
"deployed": "2019-03-24"
}
}
```
For string-based custom fields only. A regular expression used to validate the field's value (optional).

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# Custom Links
Custom links allow users to display arbitrary hyperlinks to external content within NetBox object views. These are helpful for cross-referencing related records in systems outside NetBox. For example, you might create a custom link on the device view which links to the current device in a Network Monitoring System (NMS).
## Fields
Custom links are created by navigating to Customization > Custom Links. Each link is associated with a particular NetBox object type (site, device, prefix, etc.) and will be displayed on relevant views. Each link has display text and a URL, and data from the NetBox item being viewed can be included in the link using [Jinja2 template code](https://jinja2docs.readthedocs.io/en/stable/) through the variable `obj`, and custom fields through `obj.cf`.
### Name
For example, you might define a link like this:
The name of the custom link. This is used primarily for administrative purposes only, although custom links of the same weight are ordered alphabetically by name when being rendered in the UI.
* Text: `View NMS`
* URL: `https://nms.example.com/nodes/?name={{ obj.name }}`
### Content Type
When viewing a device named Router4, this link would render as:
The type of NetBox object to which this custom link applies.
```no-highlight
<a href="https://nms.example.com/nodes/?name=Router4">View NMS</a>
```
### Weight
Custom links appear as buttons in the top right corner of the page. Numeric weighting can be used to influence the ordering of links, and each link can be enabled or disabled individually.
A numeric weight used to override alphabetic ordering of links by name. Custom fields with a lower weight will be listed before those with a higher weight. (Note that weight applies within the context of a custom link group, if defined.)
!!! warning
Custom links rely on user-created code to generate arbitrary HTML output, which may be dangerous. Only grant permission to create or modify custom links to trusted users.
### Group Name
If this custom link should be grouped with others, specify the name of the group here. Grouped custom links will be listed in a dropdown menu attached to a single button bearing the group name.
### Button Class
The color of the UI button.
### Enabled
If not selected, the custom link will not be rendered. This can be useful for temporarily disabling a custom link.
### New Window
If selected, this will force the link to open in a new browser tab or window.
### Link Text
Jinja2 template code for rendering the button text. (Note that this does not _need_ to contain any template variables.) See below for available context data.
!!! note
Custom links which render an empty text value will not be displayed in the UI. This can be used to toggle the inclusion of a link based on object attributes.
### Link URL
Jinja2 template code for rendering the hyperlink. See below for available context data.
## Context Data
The following context data is available within the template when rendering a custom link's text or URL.
The following context variables are available in to the text and link templates.
| Variable | Description |
|-----------|-------------------------------------------------------------------------------------------------------------------|
| `object` | The NetBox object being displayed |
| `obj` | Same as `object`; maintained for backward compatability until NetBox v3.5 |
| `debug` | A boolean indicating whether debugging is enabled |
| `request` | The current WSGI request |
| `user` | The current user (if authenticated) |
| `perms` | The [permissions](https://docs.djangoproject.com/en/stable/topics/auth/default/#permissions) assigned to the user |
While most of the context variables listed above will have consistent attributes, the object will be an instance of the specific object being viewed when the link is rendered. Different models have different fields and properties, so you may need to some research to determine the attributes available for use within your template for a specific object type.
Checking the REST API representation of an object is generally a convenient way to determine what attributes are available. You can also reference the NetBox source code directly for a comprehensive list.
## Conditional Rendering
Only links which render with non-empty text are included on the page. You can employ conditional Jinja2 logic to control the conditions under which a link gets rendered.
For example, if you only want to display a link for active devices, you could set the link text to
```jinja2
{% if obj.status == 'active' %}View NMS{% endif %}
```
The link will not appear when viewing a device with any status other than "active."
As another example, if you wanted to show only devices belonging to a certain manufacturer, you could do something like this:
```jinja2
{% if obj.device_type.manufacturer.name == 'Cisco' %}View NMS{% endif %}
```
The link will only appear when viewing a device with a manufacturer name of "Cisco."
## Link Groups
Group names can be specified to organize links into groups. Links with the same group name will render as a dropdown menu beneath a single button bearing the name of the group.
## Table Columns
Custom links can also be included in object tables by selecting the desired links from the table configuration form. When displayed, each link will render as a hyperlink for its corresponding object. When exported (e.g. as CSV data), each link render only its URL.
| Variable | Description |
|-----------|-----------------------------------------------------------------------------|
| `object` | The NetBox object being displayed |
| `debug` | A boolean indicating whether debugging is enabled |
| `request` | The current WSGI request |
| `user` | The current user (if authenticated) |
| `perms` | The [permissions](../../administration/permissions.md) assigned to the user |

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# Export Templates
NetBox allows users to define custom templates that can be used when exporting objects. To create an export template, navigate to Customization > Export Templates.
## Fields
Each export template is associated with a certain type of object. For instance, if you create an export template for VLANs, your custom template will appear under the "Export" button on the VLANs list. Each export template must have a name, and may optionally designate a specific export [MIME type](https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types) and/or file extension.
### Name
Export templates must be written in [Jinja2](https://jinja.palletsprojects.com/).
The name of the export template. This will appear in the "export" dropdown list in the NetBox UI.
!!! note
The name `table` is reserved for internal use.
### Content Type
!!! warning
Export templates are rendered using user-submitted code, which may pose security risks under certain conditions. Only grant permission to create or modify export templates to trusted users.
The type of NetBox object to which the export template applies.
The list of objects returned from the database when rendering an export template is stored in the `queryset` variable, which you'll typically want to iterate through using a `for` loop. Object properties can be access by name. For example:
### Template Code
```jinja2
{% for rack in queryset %}
Rack: {{ rack.name }}
Site: {{ rack.site.name }}
Height: {{ rack.u_height }}U
{% endfor %}
```
Jinja2 template code for rendering the exported data.
To access custom fields of an object within a template, use the `cf` attribute. For example, `{{ obj.cf.color }}` will return the value (if any) for a custom field named `color` on `obj`.
### MIME Type
If you need to use the config context data in an export template, you'll should use the function `get_config_context` to get all the config context data. For example:
```
{% for server in queryset %}
{% set data = server.get_config_context() %}
{{ data.syslog }}
{% endfor %}
```
The MIME type to indicate in the response when rendering the export template (optional). Defaults to `text/plain`.
The `as_attachment` attribute of an export template controls its behavior when rendered. If true, the rendered content will be returned to the user as a downloadable file. If false, it will be displayed within the browser. (This may be handy e.g. for generating HTML content.)
### File Extension
A MIME type and file extension can optionally be defined for each export template. The default MIME type is `text/plain`.
The file extension to append to the file name in the response (optional).
### As Attachment
## REST API Integration
When it is necessary to provide authentication credentials (such as when [`LOGIN_REQUIRED`](../../configuration/security.md#login_required) has been enabled), it is recommended to render export templates via the REST API. This allows the client to specify an authentication token. To render an export template via the REST API, make a `GET` request to the model's list endpoint and append the `export` parameter specifying the export template name. For example:
```
GET /api/dcim/sites/?export=MyTemplateName
```
Note that the body of the response will contain only the rendered export template content, as opposed to a JSON object or list.
## Example
Here's an example device export template that will generate a simple Nagios configuration from a list of devices.
```
{% for device in queryset %}{% if device.status and device.primary_ip %}define host{
use generic-switch
host_name {{ device.name }}
address {{ device.primary_ip.address.ip }}
}
{% endif %}{% endfor %}
```
The generated output will look something like this:
```
define host{
use generic-switch
host_name switch1
address 192.0.2.1
}
define host{
use generic-switch
host_name switch2
address 192.0.2.2
}
define host{
use generic-switch
host_name switch3
address 192.0.2.3
}
```
If selected, the rendered content will be returned as a file attachment, rather than displayed directly in-browser (where supported).