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Interface: MessageAttachment

Defined in: message-attachments.ts:16

Add secondary attachments to your messages in Slack. Message attachments are considered a legacy part of messaging functionality. They are not deprecated per se, but they may change in the future, in ways that reduce their visibility or utility. We recommend moving to Block Kit instead. Read more about when to use message attachments.

See​

Secondary message attachments reference documentation

Properties​

actions?​

optional actions: AttachmentAction[];

Defined in: message-attachments.ts:105

app_id?​

optional app_id: string;

Defined in: message-attachments.ts:115

app_unfurl_url?​

optional app_unfurl_url: string;

Defined in: message-attachments.ts:113

author_icon?​

optional author_icon: string;

Defined in: message-attachments.ts:49

Description​

A valid URL that displays a small 16px by 16px image to the left of the author_name text. Will only work if author_name is present.

optional author_link: string;

Defined in: message-attachments.ts:44

Description​

A valid URL that will hyperlink the author_name text. Will only work if author_name is present.

author_name?​

optional author_name: string;

Defined in: message-attachments.ts:40

Description​

Small text used to display the author's name.

author_subname?​

optional author_subname: string;

Defined in: message-attachments.ts:50

blocks?​

optional blocks: AnyBlock[];

Defined in: message-attachments.ts:21

Description​

An array of layout blocks in the same format as described in the building blocks guide.

bot_id?​

optional bot_id: string;

Defined in: message-attachments.ts:116

callback_id?​

optional callback_id: string;

Defined in: message-attachments.ts:106

color?​

optional color: string;

Defined in: message-attachments.ts:31

Description​

Changes the color of the border on the left side of this attachment from the default gray. Can either be one of good (green), warning (yellow), danger (red), or any hex color code (eg. #439FE0)

fallback?​

optional fallback: string;

Defined in: message-attachments.ts:26

Description​

A plain text summary of the attachment used in clients that don't show formatted text (e.g. mobile notifications).

fields?​

optional fields: MessageAttachmentField[];

Defined in: message-attachments.ts:71

Description​

An array of MessageAttachmentField that get displayed in a table-like way (see this example). For best results, include no more than 2-3 field objects.

optional footer: string;

Defined in: message-attachments.ts:91

Description​

Some brief text to help contextualize and identify an attachment. Limited to 300 characters, and may be truncated further when displayed to users in environments with limited screen real estate.

optional footer_icon: string;

Defined in: message-attachments.ts:97

Description​

A valid URL to an image file that will be displayed beside the footer text. Will only work if footer is present. We'll render what you provide at 16px by 16px. It's best to use an image that is similarly sized.

image_url?​

optional image_url: string;

Defined in: message-attachments.ts:78

Description​

A valid URL to an image file that will be displayed at the bottom of the attachment. We support GIF, JPEG, PNG, and BMP formats. Large images will be resized to a maximum width of 360px or a maximum height of 500px, while still maintaining the original aspect ratio. Cannot be used with thumb_url.

is_app_unfurl?​

optional is_app_unfurl: boolean;

Defined in: message-attachments.ts:114

mrkdwn_in?​

optional mrkdwn_in: ("text" | "pretext" | "fields")[];

Defined in: message-attachments.ts:112

Description​

Field names that should be formatted by `mrkdwn` syntax. The fields that can be formatted in this way include the names of the fields property, or the text or pretext properties.

pretext?​

optional pretext: string;

Defined in: message-attachments.ts:36

Description​

Text that appears above the message attachment block. It can be formatted as plain text, or with `mrkdwn` by including it in the mrkdwn_in field.

preview?​

optional preview: MessageAttachmentPreview;

Defined in: message-attachments.ts:117

text?​

optional text: string;

Defined in: message-attachments.ts:65

Description​

The main body text of the attachment. It can be formatted as plain text, or with `mrkdwn` by including it in the mrkdwn_in field. The content will automatically collapse if it contains 700+ characters or 5+ line breaks, and will display a "Show more..." link to expand the content.

thumb_url?​

optional thumb_url: string;

Defined in: message-attachments.ts:86

Description​

A valid URL to an image file that will be displayed as a thumbnail on the right side of a message attachment. We currently support the following formats: GIF, JPEG, PNG, and BMP. The thumbnail's longest dimension will be scaled down to 75px while maintaining the aspect ratio of the image. The file size of the image must also be less than 500 KB. For best results, please use images that are already 75px by 75px.

title?​

optional title: string;

Defined in: message-attachments.ts:54

Description​

Large title text near the top of the attachment.

optional title_link: string;

Defined in: message-attachments.ts:58

Description​

A valid URL that turns the title text into a hyperlink.

ts?​

optional ts: string;

Defined in: message-attachments.ts:104

Description​

A Unix timestamp that is used to relate your attachment to a specific time. The attachment will display the additional timestamp value as part of the attachment's footer. Your message's timestamp will be displayed in varying ways, depending on how far in the past or future it is, relative to the present. Form factors, like mobile versus desktop may also transform its rendered appearance.