Webhook Events
Programmable Chat has been deprecated and is no longer supported. Instead, we'll be focusing on the next generation of chat: Twilio Conversations. Find out more about the EOL process here.
If you're starting a new project, please visit the Conversations Docs to begin. If you've already built on Programmable Chat, please visit our Migration Guide to learn about how to switch.
Programmable Chat sends webhooks for most things that happen in your app, and are designed to allow you to monitor and intercept user actions in your own backend service, in a Function, or in a Studio flow.
Webhook targets for the Service instance (the URL that Twilio will invoke) are configured in the Twilio Console. Twilio will fire these webhooks at two different moments:
- Pre-Event Webhooks will fire before an action has been committed to the Chat instance, blocking publication until a response is received. This gives your backend (or Function) the opportunity to intercept, modify, or reject any action across the instance, making these hooks useful for spam/language filtering, complex permission schemes, or other business logic. Pre-event webhooks are fired only for actions from the Chat SDK; the REST API actions will never fire them.
- Post-Event Webhooks fire after any action taken on a Chat Service. This means they arrive after messages have been delivered, after channel membership has changed, etc. Post-Event hooks are therefore the right tool for archiving or post-processing. Unlike Pre-Event webhooks, Post-Event webhooks can also be triggered from the REST API if the correct header is passed (see below).
Additionally to global, service-level webhooks, Channel-Scoped Webhooks allow you to configure up to five specific webhooks per channel, optionally triggering them on specific words or phrases.
Twilio can send your web application an HTTP request when certain events happen, such as an incoming text message to one of your Twilio phone numbers. These requests are called webhooks, or status callbacks. For more, check out our guide to Getting Started with Twilio Webhooks. Find other webhook pages, such as a security guide and an FAQ in the Webhooks section of the docs.
Table of Contents
Webhook Event Triggers
Most events — but not all of them — have both a pre-event and a post-event webhook. The former is fired before the event has been published, and Twilio waits for a response before publishing it. The latter are fired after publication, assuming the event was not rejected by your pre-event webhook response.
The below table enumerates all Chat webhook events in corresponding pairs.
Pre-Event | Post-Event | Description (incl. Post-Event) |
onMessageSend |
onMessageSent |
Fires when a new message is posted to a channel. |
onMessageRemove |
onMessageRemoved |
Fires when a message is deleted from a channel. |
onMessageUpdate |
onMessageUpdated |
Fires when a posted message's body or any attribute is changed. |
onMediaMessageSend |
onMediaMessageSent |
Fires when a new media message is posted to a channel. |
onChannelAdd |
onChannelAdded |
Fires when a new channel, public or private, is created. |
onChannelUpdate |
onChannelUpdated |
Fires when any attribute of a channel is changed. |
onChannelDestroy |
onChannelDestroyed |
Fires when a channel is removed from the Service. |
onMemberAdd |
onMemberAdded |
Fires when a User has joined a Channel as a Member. |
onMemberUpdate |
onMemberUpdated |
Fires when Member's attributes are updated. |
onMemberRemove |
onMemberRemoved |
Fires when a User is removed from the set of Channel Members. |
(no pre-event webhook) |
onUserAdded |
Fires when a new User has been created. (cannot be intercepted with a Pre-Event hook) |
onUserUpdate |
onUserUpdated |
Fires when any configurable attribute of a User is changed. For User's reachability status update only Post-Event webhook is triggered. |
Triggering Webhooks for REST API Events
Upon configuration, only actions from SDK-driven clients (like mobile phones or browsers) will cause webhooks without further action on your part. This includes both Service-level webhooks and Channel-Scoped Webhooks, and as a default behavior helps avoid infinite feedback loops.
Your Post-Event Webhook target, however, may be an important tool for archiving. In this case, you may also want to enable webhook "echoes" from actions you take on the REST API. To do so, you can add a header X-Twilio-Webhook-Enabled=true
to any such request. Requests bearing this header will yield webhooks to the configured Post-Event webhook target.
Using Pre-Event Webhooks to Modify or Reject Changes
In the case of Pre-Event webhooks, Twilio will wait for a response from your service before publishing a result. The arrival, HTTP status code, and content of your response determines how Programmable Chat will proceed.
Response Status Code | Body | Result |
HTTP 200 OK | {} (or no content) |
Chat will publish the change unmodified. |
HTTP 200 OK |
|
Chat will publish the change with modifications as given in the response. All values are optional, and missing fields will be left unmodified from the original event. See below for which fields can be modified for each data type (Channels, Messages, or Users). If modified values fail validation, the error will be returned to the SDK (or REST client) that triggered the event. |
HTTP 403 Forbidden | (none) | Chat will reject the change and no publication will be made. |
HTTP 404 Not Found | (none) | Chat will publish the change unmodified. |
(no response or timeout) | Chat will publish the change unmodified. |
Modifiable Fields
In all cases, any change to the attributes
value will be applied wholly; you cannot partially-update this value by providing only a subset of fields. The new value for attributes, as ever, must be provided as a string with all intervening double-quotes escaped.
Channel Events
In response to the onChannelAdd and onChannelUpdate events, your Pre-Event Webhook response may modify the following properties of the channel:
friendly_name
unique_name
attributes
An example response modifying a channel
HTTP 200 OK
Content-Type: text/json
{
"friendly_name": "friendly name of channel",
"unique_name": "very unique name",
"attributes" : "{\"key\" : \"value\"}"
}
Message Events
In response to onMessageSend and onMessageUpdate events, your Pre-Event Webhook response may modify the following properties of the message:
body
attributes
An example response modifying a chat message.
HTTP 200 OK
Content-Type: text/json
{
"body": "modified message text",
"attributes": "{\"key\" : \"value\"}"
}
User Events
In response to onUserUpdate events, your Pre-Event Webhook response may modify the following properties of the User:
friendly_name
attributes
An example response modifying a chat User.
HTTP 200 OK
Content-Type: text/json
{
"friendly_name": "modified friendly name",
"attributes": "{\"key\" : \"value\"}"
}
Selective muting for Push notifications
Additionally, in response to onMessageSend, OnMemberAdd and OnMemberRemove the following property can be modified - mute_notification
. This allows to supress Push notification for named events.
HTTP 200 OK
Content-Type: text/json
{
"mute_notification": "true"
}
Configuring Webhooks with the REST API
Service-level Webhooks, both Pre-Event and Post-Event, are configured on the Service itself with the following parameters.
Configuration Attribute | Type | Meaning |
PreWebhookUrl |
string (absolute url) | The absolute URL where Twilio should send Pre-Event webhook requests. |
PostWebhookUrl |
string (absolute url) | The absolute URL where Twilio should send Post-Event webhook requests. |
WebhookMethod |
string ("POST" or "GET") | Twilio will use this HTTP method when sending webhook requests of all types. |
WebhookFilters |
string, repeatable | The list of webhook event triggers that are enabled for this Service. The entire list must be provided on any POST to Service configuration. |
PreWebhookRetryCount |
integer [0, 3] | Pre-Event webhooks that fail after a 5s timeout will be retried according to this setting. The maximum number of retries is 3 (i.e. 4 attempts total). |
PostWebhookRetryCount |
integer [0, 3] | Post-Event webhooks that fail after a 5s timeout will be retried according to this setting. The maximum number of retries is 3 (i.e. 4 attempts total). |
Webhook Bodies by Event Type
When Twilio makes an HTTP request to your server, it will include contextual information related to the action that triggered the WebHook call to your backend.
In addition to the event-specific parameters, each request will also contain the following parameters and information:
parameter name | type | description |
---|---|---|
AccountSid | string, SID | The Twilio Account SID which the Service instance belongs to |
InstanceSid | string, sid | The Programmable Chat Service instance SID which the action relates to |
ClientIdentity | string | The identity string of the SDK client endpoint that triggered the event callback (as taken from the Access Token for the client endpoint). |
Note: Each HTTP request is issued with the Content-Type
header application/x-www-urlencoded
.
Pre-Event Webhook Bodies
OnMessageSend
parameter name | type | description |
---|---|---|
EventType | string | Always onMessageSend |
ChannelSid | string | Channel SID identifier of the Channel the Message is being sent to |
Body | string | The body of message |
Attributes | string, optional, valid JSON structure or null | A JSON structure contained in a string. This can be null if attributes are not present in message entity. |
From | string | The author of the message |
DateCreated | date string | The timestamp of creation of the message (DEPRECATED) |
To | string | Channel String Identifier of the Channel the Message is being sent to (DEPRECATED) |
OnMessageRemove
parameter name | type | description |
---|---|---|
EventType | string | Always onMessageRemove |
MessageSid | string | The Message SID |
ChannelSid | string | SID identifier of the Channel the Message is being sent to |
Body | string | The body of message |
Attributes | string, optional, valid JSON structure or null | Stringified JSON structure. This can be null if attributes are not present in message entity. |
From | string | The author of the message |
DateCreated | date string | The timestamp from message creation |
RemovedBy | string | The remover of the message |
To | string | Channel String Identifier of the Channel the Message is being sent to (DEPRECATED) |
OnMessageUpdate
parameter name | type | description |
---|---|---|
EventType | string | Always onMessageUpdate |
MessageSid | string | The Message SID |
ChannelSid | string | SID identifier of the Channel the Message is being sent to |
Body | string | The body of message |
Attributes | string, optional, valid JSON structure or null | Stringified JSON structure. This can be null if attributes are not present in message entity |
From | string | The author of the message |
DateCreated | date string | The timestamp from message creation |
ModifiedBy | string | The updater/modifier of the message |
To | string | Channel String Identifier of the Channel the Message is being sent to (DEPRECATED) |
OnMediaMessageSend
parameter name | type | description |
---|---|---|
EventType | string | Always onMediaMessageSend |
ChannelSid | string | Channel SID identifier of the Channel the Message is being sent to |
Body | string | The body of message |
Attributes | string, optional, valid JSON structure or null | A JSON structure contained in a string. This can be null if attributes are not present in message entity. |
From | string | The author of the message |
MediaFilename | string | The filename of the underlying media file as specified when uploaded |
MediaContentType | string | The MIME type of the file this media represents. |
MediaSid | string | Media SID identifier |
MediaSize | int | Media size in bytes |
DateCreated | date string | The timestamp of creation of the message (DEPRECATED) |
To | string | Channel String Identifier of the Channel the Message is being sent to (DEPRECATED) |
OnChannelAdd
parameter name | type | description |
---|---|---|
EventType | string | Always onChannelAdd |
Attributes | string, optional, valid JSON structure or null | Stringified JSON structure. This can be null if attributes are not present in channel entity |
CreatedBy | string | The identity of the user that created a channel |
FriendlyName | string, optional | The friendly name of the channel, if set |
UniqueName | string, optional | The unique name of the channel, if set |
ChannelType | string | The Channel type. Either private or public |
DateCreated | date string | The date of creation of the channel (DEPRECATED) |
Name | string, optional | The friendly name of the channel, if set (DEPRECATED) |
ChannelSid | string | Channel String Identifier (DEPRECATED) |
OnChannelDestroy
parameter name | type | description |
---|---|---|
EventType | string | Always onChannelDestroy |
ChannelSid | string | Channel String Identifier |
Attributes | string, optional, valid JSON structure or null | Stringified JSON structure. This can be null if attributes are not present in channel entity |
DateCreated | string | The date of creation of the channel |
CreatedBy | date string | The identity of the user that created a channel |
FriendlyName | string, optional | The friendly name of the channel, if set |
UniqueName | string, optional | The unique name of the channel, if set |
ChannelType | string | The Channel type. Either private or public |
Name | string, optional | The friendly name of the channel, if set (DEPRECATED) |
OnChannelUpdate
parameter name | type | description |
---|---|---|
EventType | string | Always onChannelUpdate |
ChannelSid | string | Channel String Identifier |
Attributes | string, optional, valid JSON structure or null | Stringified JSON structure. This can be null if attributes are not present in channel entity. |
DateCreated | date string, | The date of creation of the channel |
CreatedBy | string | The identity of the user that created a channel |
FriendlyName | string, optional | The friendly name of the channel, if set |
UniqueName | string, optional | The unique name of the channel, if set |
Name | string, optional | The friendly name of the channel, if set (DEPRECATED) |
OnMemberAdd
parameter name | type | description |
---|---|---|
EventType | string | Always onMemberAdd |
ChannelSid | string | Channel String Identifier |
Identity | string | The Identity of the User being added to the channel as a Member |
RoleSid | string, optional | The Role SID of added member |
Reason | string | The reason for the addition of the member. Could be: ADDED or JOINED |
Role | string, optional | The role of added member (DEPRECATED) |
OnMemberRemove
parameter name | type | description |
---|---|---|
EventType | string | Always onMemberRemove |
ChannelSid | string | Channel String Identifier |
Identity | string | The Identity of the User being removed from the channel |
MemberSid | string | The member SID of member being removed |
RoleSid | string, optional | The role of removed member |
Reason | string | The reason of the removal of the member. Could be: REMOVED or LEFT |
Role | string, optional | The role of removed member (DEPRECATED) |
OnMemberUpdate
parameter name | type | description |
---|---|---|
EventType | string | Always onMemberUpdate |
ChannelSid | string | Channel String Identifier |
Identity | string | The Identity of the Member being updated |
MemberSid | string | The member SID identifier |
RoleSid | string, optional | The role of updated member |
DateCreated | string, ISO8601 time | Creation date of member |
Attributes | JSON, string, optional | The optional Attributes (if set) of the Member being updated as a JSON structure in string format |
OnUserUpdate
parameter name | type | description |
---|---|---|
UserSid | string, SID | The SID of the User about to be updated |
EventType | string | Always onUserUpdate |
Identity | string | The Identity of the User being updated |
FriendlyName | string, optional | The optional (if set) FriendlyName of the User being updated |
RoleSid | string | The Role SID the user being updated |
DateCreated | string, ISO8601 time | The date and time of initial User creation |
DateUpdated | string, ISO8601 time | The date and time the user was last updated |
Attributes | JSON, string, optional | The optional Attributes (if set) of the User being updated as a JSON structure in string format. |
IsOnline | boolean, optional | true if the user has an active session and can create and receive real-time events. This field is present only if the Reachability Indicator feature is enabled for the Service instance. |
IsNotifiable | boolean, optional | true if the user has an active session and can create and receive push notifications. This field is present only if the Reachability Indicator and Push Notifications features are enabled for the Service instance. The User must have at least one Push Notification registration for Chat. |
Post-Event Webhook Bodies
OnMessageSent
parameter name | type | description |
---|---|---|
EventType | string | Always onMessageSent |
MessageSid | string | The Message SID of the new Message |
Index | int | The index of the Message within the Channel Message list |
ChannelSid | string | Channel SID identifier of the Channel the Message is being sent to |
Body | string | The body of the message |
Attributes | string, optional, valid JSON structure or null | Stringified JSON structure. This can be null if attributes are not present in message entity |
From | string | The author of the message |
DateCreated | date string | The timestamp of message creation |
OnMessageRemoved
parameter name | type | description |
---|---|---|
EventType | string | Always onMessageRemoved |
MessageSid | string | The Message SID of the removed Message |
Index | int | The index of the removed Message within the Channel Message list |
ChannelSid | string | The SID identifier of the Channel the Message is being sent to |
Body | string | The body of message |
Attributes | string, optional, valid JSON structure or null | Stringified JSON structure. This can be null if attributes are not present in message entity |
From | string | The author of the message |
RemovedBy | string | The remover of the message |
DateCreated | date string | The timestamp of message creation |
DateRemoved | date string | The timestamp of removal of the message |
OnMessageUpdated
parameter name | type | description |
---|---|---|
EventType | string | Always onMessageUpdated |
MessageSid | string | The Message SID of the updated Message |
Index | int | The index of the updated Message within the Channel Message list |
ChannelSid | string | SID identifier of the Channel the Message is being sent to |
Body | string | The body of message |
Attributes | string, optional, valid JSON structure or null | Stringified JSON structure. This can be null if attributes are not present in message entity |
From | string | The author of the message |
ModifiedBy | string | The identity of the user that updated the message |
DateCreated | date string | The timestamp of message creation |
DateUpdated | date string | The timestamp of update of the message |
OnMediaMessageSent
parameter name | type | description |
---|---|---|
EventType | string | Always onMediaMessageSent |
MessageSid | string | The Message SID of the new Message |
Index | int | The index of the Message within the Channel Message list |
ChannelSid | string | Channel SID identifier of the Channel the Message is being sent to |
Body | string | The body of the message |
Attributes | string, optional, valid JSON structure or null | Stringified JSON structure. This can be null if attributes are not present in message entity |
From | string | The author of the message |
DateCreated | date string | The timestamp of message creation |
MediaFilename | string | The filename of the underlying media file as specified when uploaded |
MediaContentType | string | The MIME type of the file this media represents. |
MediaSid | string | Media SID identifier |
MediaSize | int | Media size in bytes |
OnChannelAdded
parameter name | type | description |
---|---|---|
EventType | string | Always onChannelAdded |
ChannelSid | string | The SID of the newly added Channel |
Attributes | string, optional, JSON structure | The arbitrary JSON structure of the channel |
DateCreated | date string | The date of channel creation |
CreatedBy | string | The identity of the user that created a channel |
FriendlyName | string, optional | The friendly name of the channel, if set |
UniqueName | string, optional | The unique name of the channel, if set |
ChannelType | string | The Channel type. Either private or public |
OnChannelDestroyed
parameter name | type | description |
---|---|---|
EventType | string | Always onChannelDestroyed |
ChannelSid | string | Channel String Identifier |
Attributes | string, optional, JSON structure | The arbitrary JSON structure of the channel |
DateCreated | date string, | The date of creation of the channel |
DateDestroyed | date string, | The date of destruction of the channel |
CreatedBy | string | The identity of the user that created a channel |
FriendlyName | string, optional | The friendly name of the channel, if set |
UniqueName | string, optional | The unique name of the channel, if set |
ChannelType | string | The Channel type. Either private or public |
OnChannelUpdated
parameter name | type | description |
---|---|---|
EventType | string | Always onChannelUpdated |
ChannelSid | string | Channel String Identifier |
Attributes | string, optional, JSON structure | The arbitrary JSON structure of the channel |
DateCreated | date string, | The date of creation of the channel |
DateUpdated | date string | The date of update of the channel |
CreatedBy | string | The identity of the user that created a channel |
FriendlyName | string, optional | The friendly name of the channel, if set |
UniqueName | string, optional | The unique name of the channel, if set |
ChannelType | string | The Channel type. Either private or public |
OnMemberAdded
parameter name | type | description |
---|---|---|
EventType | string | Always onMemberAdded |
MemberSid | string | The Member SID of the newly added Member |
ChannelSid | string | Channel String Identifier |
Identity | string | The Identity of the User being added to the channel as a Member |
RoleSid | string, optional | The Role SID of added member |
Reason | string | The reason for the addition of the member. Could be ADDED or JOINED |
DateCreated | date string | The date of Member addition |
OnMemberRemoved
parameter name | type | description |
---|---|---|
EventType | string | Always onMemberRemoved |
ChannelSid | string | Channel String Identifier |
Identity | string | The Identity of the User being removed from the channel |
MemberSid | string | The Member SID of member being removed |
RoleSid | string, optional | The role of removed member |
Reason | string | The reason for the removal of the member. Could be REMOVED or LEFT |
DateCreated | date string | The date of Member addition |
DateRemoved | date string | The date of Member removal |
OnMemberUpdated
parameter name | type | description |
---|---|---|
EventType | string | Always onMemberUpdated |
ChannelSid | string | Channel String Identifier |
Identity | string | The Identity of the updated member |
MemberSid | string | The member SID identifier |
RoleSid | string, optional | The role of updated member |
DateCreated | string, ISO8601 time | Creation date of member |
DateUpdated | string, ISO8601 time | The date when member was last updated |
Attributes | JSON, string, optional | The optional Attributes (if set) of the Member being updated as a JSON structure in string format |
LastConsumedMessageIndex | int, optional | Index of the last consumed message by the member |
OnUserUpdated
parameter name | type | description |
---|---|---|
UserSid | string, SID | The SID of the User that was updated. |
EventType | string | Always onUserUpdated |
Identity | string | The Identity of the User that was updated |
FriendlyName | string, optional | The optional FriendlyName (if set) of the updated User |
RoleSid | string | The Role SID the User that was updated |
DateCreated | string, ISO8601 time | The date and time the User was first created |
DateUpdated | string, ISO8601 time | The date and time the User was updated |
Attributes | JSON, string, optional | The optional Attributes of the updated user (if set). JSON structure in string format. |
IsOnline | boolean, optional | true if the user has an active session and can create and receive real-time events. This field is present only if Reachability Indicator feature is enabled for the Service instance. |
IsNotifiable | boolean, optional | true if the user has an active session and can create and receive push notifications. This field is present only if the Reachability Indicator and Push Notifications features are enabled for the Service instance. The User must also have at least one Push Notification registration for Chat. |
OnUserAdded
parameter name | type | description |
---|---|---|
UserSid | string, SID | The SID of the User that was updated. |
EventType | string | Always onUserAdded |
Identity | string | The Identity of the User that was updated |
FriendlyName | string, optional | The optional FriendlyName (if set) of the updated User |
RoleSid | string | The Role SID the User that was updated |
DateCreated | string, ISO8601 time | The date and time the User was first created |
Attributes | JSON, string, optional | The optional Attributes of the updated user (if set). JSON structure in string format. |
Need some help?
We all do sometimes; code is hard. Get help now from our support team, or lean on the wisdom of the crowd by visiting Twilio's Stack Overflow Collective or browsing the Twilio tag on Stack Overflow.