/chat.postMessage - Slack Web API

Sends a message to a channel.

{ "channel": "C1H9RESGL", "message": { "attachments": [ { "fallback": "This is an attachment's fallback", "id": 1, "text": "This is an attachment" } ], "bot_id": "B19LU7CSY", "subtype": "bot_message", "text": "Here's a message for you", "ts": "1503435956.000247", "type": "message", "username": "ecto1" }, "ok": true, "ts": "1503435956.000247" }

Request

Header Params

token

string

required

Authentication token. Requires scope: chat:write

Body Params application/x-www-form-urlencoded

as_user

string

optional

Pass true to post the message as the authed user, instead of as a bot. Defaults to false. See authorship below.

attachments

string

optional

A JSON-based array of structured attachments, presented as a URL-encoded string.

blocks

string

optional

A JSON-based array of structured blocks, presented as a URL-encoded string.

channel

string

required

Channel, private group, or IM channel to send message to. Can be an encoded ID, or a name. See below for more details.

icon_emoji

string

optional

Emoji to use as the icon for this message. Overrides icon_url. Must be used in conjunction with as_user set to false, otherwise ignored. See authorship below.

icon_url

string

optional

URL to an image to use as the icon for this message. Must be used in conjunction with as_user set to false, otherwise ignored. See authorship below.

link_names

string

optional

Find and link channel names and usernames.

mrkdwn

string

optional

Disable Slack markup parsing by setting to false. Enabled by default.

parse

string

optional

Change how messages are treated. Defaults to none. See below.

reply_broadcast

string

optional

Used in conjunction with thread_ts and indicates whether reply should be made visible to everyone in the channel or conversation. Defaults to false.

text

string

optional

How this field works and whether it is required depends on other fields you use in your API call. See below for more detail.

thread_ts

string

optional

Provide another message's ts value to make this message a reply. Avoid using a reply's ts value; use its parent instead.

unfurl_links

string

optional

Pass true to enable unfurling of primarily text-based content.

unfurl_media

string

optional

Pass false to disable unfurling of media content.

username

string

optional

Set your bot's user name. Must be used in conjunction with as_user set to false, otherwise ignored. See authorship below.

Responses

🟢200Typical success response

application/json

Body

Schema for successful response of chat.postMessage method

channel

string

required

Match pattern:

^[CGD][A-Z0-9]{8,}$

message

object (Message object)

required

attachments

array [object {6}]

optional

>= 1 items

blocks

array [object {2}]

optional

This is a very loose definition, in the future, we'll populate this with deeper schema in this definition namespace.

bot_id

array [anyOf]

optional

bot_profile

object (Bot Profile Object)

optional

client_msg_id

string

optional

comment

object (File Comment Object)

optional

display_as_bot

boolean

optional

file

object (file object)

optional

files

array[object (file object) {70}]

optional

>= 1 items

icons

object

optional

inviter

string

optional

Match pattern:

^[UW][A-Z0-9]{2,}$

is_delayed_message

boolean

optional

is_intro

boolean

optional

is_starred

boolean

optional

last_read

string

optional

Match pattern:

^\d{10}\.\d{6}$

latest_reply

string

optional

Match pattern:

^\d{10}\.\d{6}$

name

string

optional

old_name

string

optional

parent_user_id

string

optional

Match pattern:

^[UW][A-Z0-9]{2,}$

permalink

string <uri>

optional

pinned_to

array[string]

optional

purpose

string

optional

reactions

array[object (Reaction object) {4}]

optional

reply_count

integer

optional

reply_users

array[string]

optional

>= 1 items

reply_users_count

integer

optional

source_team

string

optional

Match pattern:

^[TE][A-Z0-9]{8,}$

subscribed

boolean

optional

subtype

string

optional

team

string

optional

Match pattern:

^[TE][A-Z0-9]{8,}$

text

string

required

thread_ts

string

optional

Match pattern:

^\d{10}\.\d{6}$

topic

string

optional

string

required

Match pattern:

^\d{10}\.\d{6}$

type

string

required

unread_count

integer

optional

upload

boolean

optional

user

string

optional

Match pattern:

^[UW][A-Z0-9]{2,}$

user_profile

object (objs_user_profile_short)

optional

user_team

string

optional

Match pattern:

^[TE][A-Z0-9]{8,}$

username

string

optional

enum<boolean>

required

Allowed value:

true

string

required

Match pattern:

^\d{10}\.\d{6}$

🔴500Typical error response if too many attachments are included