SevenTV / EventAPI

A service which provides live updates for various resources implementing the Server-Sent Events and WebSocket specs
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THIS REPO IS ARCHIVED PLEASE SEE

https://github.com/seventv/seventv

for more info

7TV EventAPI

The Event API allows developers to receive real-time updates on 7TV data and implement instantaneous feedback in applications. This service is used primarily to push channel emote changes to clients without requiring a manual refresh and it powers systems such as personal emotes. To get started on using this service see the documentation below.

Supported Protocols

API Documentation

Versions

Base URL: https://events.7tv.io

Name Status
V3 ✅ Supported
V2 Skipped
V1 ⚠️ Deprecated

Opcodes

Operation codes are used to identify what kind of payload an event contains.

Op Name Type Description
0 Dispatch ⬇️ A standard event message, sent when a subscribed event is emitted
1 Hello ⬇️ Received upon connecting, presents info about the session
2 Heartbeat ⬇️ Ensures the connection is still alive
4 Reconnect ⬇️ Server wants the client to reconnect
5 Ack ⬇️ Server acknowledges an action by the client
6 Error ⬇️ An error occured, you should log this
7 End of Stream ⬇️ The server will send no further data and imminently end the connection
33 Identify ⬆️ Authenticate with an account
34 Resume ⬆️ Try to resume a previous session
35 Subscribe ⬆️ Watch for changes on specific objects or sources. Don't smash it!
36 Unsubscribe ⬆️ Stop listening for changes
37 Signal ⬆️

Legends: ⬆️ sent by client, ⬇️ sent by server

Close codes

Close codes provide a reason for the closure of a connection to help clients understand what happened.

Code Name Description Reconnect?
4000 Server Error an error occured on the server's end Yes
4001 Unknown Operation the client sent an unexpected opcode No¹
4002 Invalid Payload the client sent a payload that couldn't be decoded No¹
4003 Auth Failure the client unsucessfully tried to identify No¹
4004 Already Identified the client wanted to identify again No¹
4005 Rate Limited the client is being rate-limited Maybe³
4006 Restart the server is restarting and the client should reconnect Yes
4007 Maintenance the server is in maintenance mode and not accepting connections Yes²
4008 Timeout the client was idle for too long Yes
4009 Already Subscribed the client tried to subscribe to an event twice No¹
4010 Not Subscribed the client tried to unsubscribe from an event they weren't subscribing to No¹
4011 Insufficient Privilege the client did something that they did not have permission for Maybe³

¹ this code indicate a bad client implementation. you must log such error and fix the issue before reconnecting ² reconnect with significantly greater delay, i.e at least 5 minutes, including jitter ³ only reconnect if this was initiated by action of the end-user

Payloads

Dispatch (0)

Key Type Description
type EventType the event type
body ChangeMap detailed changes
ChangeMap
Key Type Description
id ObjectID the object's ID
kind int8 the object kind
contextual? bool if true, this event represents a change local only to the current session
actor User the user responsible for these changes
added? []ChangeField a list of added fields
updated? []ChangeField a list of updated fields
removed? []ChangeField a list of removed fields
pushed? []ChangeField a list of items pushed to an array
pulled? []ChangeField a list of items pulled from an array
ChangeField
Key Type Description
key string the key in context
index int? if the field is an array, this is the index of the item within the array that was updated
nested¹ bool if true, this means the current value is nested deeper
old_value object or nil the previous value
value object, []ChangeField or nil the new value

¹ the value field will always be []ChangeField when nested is true.

Hello (1)

Key Type Description
heartbeat_interval uint32 interval in milliseconds between each heartbeat
session_id string unique token for this session, used for resuming and mutating the session
subscription_limit int32 the maximum amount of subscriptions this connection can initiate

Heartbeat

Key Type Description
count uint64 The amount of heartbeats so far

Ack (5)

Key Type Description
command string the acknowledged sent opcode in text form
data echo the data sent by the client

Resume (34)

Key Type Description
session_id string the id of the previous session

Subscribe (35)

Key Type Description
type string subscription type
condition string map filter messages by conditions

Example


{
"op": 35,
"d": {
"type": "emote_set.update",
"condition": {
// valid fields in the condition depend on the subscription type
// though in most cases except creations, object_id is acceptable
// to filter for a specific object.
        "object_id": "62cdd34e72a832540de95857"
    }
}

}


#### Unsubscribe (36)

| Key        |    Type    |          Description          |
| ---------- | :--------: | :---------------------------: |
| type       |   string   |       subscription type       |
| condition? | string map | filter messages by conditions |

```jsonc
{
  "op": 36, 
  "d": {
    "type": "emote_set.update",
    "condition": {
      "object_id": "62cdd34e72a832540de95857"
    }
  }
}

End of Stream (7)

End of Stream events are sent when the connection is closed by the server.

The close code provided in the event indicates the reason for the disconnect and whether or not the client should reconnect.

Key Type Description
code uint16 close code
message string a text message about the closure

Subscription types

Subscription Types
Type Kind
System - Announcement system.announcement
Create Emote emote.create
Update Emote emote.update
Delete Emote emote.delete
Create Emote Set emote_set.create
Update Emote Set emote_set.update
Delete Emote Set emote_set.delete
Create User user.create
Update User user.update
Delete User user.delete
Add User Connection user.add_connection
Update User Connection user.update_connection
Delete User Connection user.delete_connection
Create Cosmetic cosmetic.create
Update Cosmetic cosmetic.update
Delete Cosmetic cosmetic.delete
Create Entitlement entitlement.create
Update Entitlement entitlement.update
Delete Entitlement entitlement.delete

If you'd like to receive all events about an object, it is also possible to use an asterisk symbol as a wildcard. For example, using the type emote.* will subscribe to each of emote.create, emote.update and emote.delete.


EventStream / Server-Sent Events (HTTP)

EventStream, or Server-Sent Events (SSE) is the recommended way to use the EventAPI. This is a one-way stream which operates via a regular HTTP connection rather than a different protocol such as WebSocket.

The EventStream access point is https://events.7tv.io/v3. The following sections will cover how to initiate and modify the connection.

Message Structure (EventStream)

In a browser environment, the EventSource interface exists to automatically handle an EventStream endpoint.

Otherwise, to read and parse this data refer to the spec for Server-Sent Events.

Opcodes are sent in their text form as the event's type, and the data will always be JSON.

Connection (EventStream)

Upon opening the connection, you will receive a [1] HELLO event.

Inline Event Subscriptions (EventStream)

It is possible to add subscriptions directly in the connection string, by appending a @ to the URL followed by a URL-encoded string with the following syntax,

{type}<{condition1}={value1};{condition2}={value2}>;...

where type is a subscription type, then wrapped between brackets (<...>) are a list of conditions. Separate each subscription by a comma. The same type can be subscribed to multiple times with different conditions.

The entire inline subscription string must be URL-encoded.

Full examples

Subscribe to updates on a specific emote set
: GET https://events.7tv.io/v3@emote_set.update<object_id=62cdd34e72a832540de95857>

Subscribe to all entitlement and cosmetic events on a specific channel
: GET https://events.7tv.io/v3@entitlement.*<host_id=60867b015e01df61570ab900;connection_id=1234>,cosmetic.*<host_id=60867b015e01df61570ab900;connection_id=1234>

At this time, it is possible to subscribe with no conditions and effectively turn the connection into a Firehose, however this may be restricted in the future.

Managing subscriptions (EventStream)

Adding or removing a subscription is done by sending a request via a REST endpoint and passing your session ID to authenticate.

The endpoint for managing subscriptions is currently unavailable. You may use Inline Event Subscriptions in the meantime.

Acks (EventStream)

An ack will be sent when the session is mutated, such as when subscribing or unsubscribing. ACKs are also sent when using Inline Event Subscriptions immediately after the session becomes ready. This can be used to confirm the validity of the inline subscription string.

Handling ACKs is optional, but allows an implementation to confirm that the server accepted their input.

Dispatches (EventStream)

Once subscriptions are active, you will receive [0] DISPATCH events


WebSocket

For apps which must issue commands frequently, WebSocket may be a better choice.

The websocket access point is wss://events.7tv.io/v3. The following sections will cover how to maintain and modify the connection.

Message Structure (WebSocket)

WebSocket messages are sent in JSON format and are composed of three root properties, op is the opcode, t is the timestamp of the message's formation, and d is the data payload.

Key Type Description
op uint8 message operation code
t date timestamp of the message's formation in unix millis
d object generic data payload

Connection (WebSocket)

Upon establishing a connection, you will receive a [1] HELLO event.

Heartbeat (WebSocket)

The server will send periodic heartbeats at the interval specified in the Hello payload. If heartbeats are missed for 3 cycles, the connection can be considered dead (i.e due to an error or network issue) and you should reconnect.

Resuming (WebSocket)

When a connection is dropped with a non-normal, non-error closure, it is possible to resume the session to restore subscriptions and replay missed events.

To initiate a resume, send the opcode [34] RESUME and pass the session ID from the previous connection. If successful, the server will acknowledge the resume with an [5] ACK. Previous subscriptions will be restored, and missed [0] DISPATCH events will replay in sequence.

Managing subscriptions (WebSocket)

A subscription consists of a type and a condition. This is where you can choose exactly what kind of data your application needs.

Valid subscription types can be found here.

Subscribing (WebSocket)

To set up a subscription, you may send the opcode [35] SUBSCRIBE and these fields

You are allowed to subscribe multiple times to the same type, however, duplicated conditions will result in a disconnect with code 4009 Already Subscribed.

Unsubscribing (WebSocket)

When an event source is no longer needed, you should unsubscribe from it to avoid receiving unnecessary data with [36] UNSUBSCRIBE.

It is also possible to unsubscribe from an entire event type at once by leaving the condition field empty.

Acks (WebSocket)

An ack will be sent when a command is successfully executed, such as subscribing or unsubscribing. Handling ACKs is optional, but allows an implementation to confirm that the server accepted their input.

Dispatches (WebSocket)

Once subscriptions are active, you may start receiving messages with the [0] DISPATCH opcode. These events notify of changes to an object and allow you to keep your state up to date.


View legacy v1 documentation