Querying Channels

If you’re building a similar application to Facebook Messenger or Intercom, you’ll want to show a list of Channels. The Chat API supports MongoDB style queries to make this easy to implement.

You can query channels based on built-in fields as well as any custom field you add to channels. You can find the complete list of supported operators in the query syntax section of the docs.

Multiple filters can be combined, but more complex filters can increase the latency of this API, particularly with custom fields. Reach out to support if you have any doubts about your query filter or logic.

As an example, let’s say that you want to query the last conversations I participated in sorted by last_message_at.

Stream Chat does not run MongoDB on the backend, only a subset of the query options are available.

Here’s an example of how you can query the list of channels:

val request = QueryChannelsRequest(
  filter = Filters.and(
    Filters.eq("type", "messaging"),
    Filters.`in`("members", listOf("thierry")),
  ),
  offset = 0,
  limit = 10,
  querySort = QuerySortByField.descByName("lastMessageAt")
).apply {
  watch = true
  state = true
}

client.queryChannels(request).enqueue { result ->
  if (result.isSuccess) {
    val channels: List<Channel> = result.data()
  } else {
    // Handle result.error()
  }
}

const filter = { type: 'messaging', members: { $in: ['thierry'] } };
const sort = [{ last_message_at: -1 }];

const channels = await chatClient.queryChannels(filter, sort, {
  watch: true, // this is the default
  state: true,
});

channels.map((channel) => {
    console.log(channel.data.name, channel.cid)
  })
}

final filter = Filter.in_('members',['thierry']);

final sort = [SortOption("last_message_at", direction: SortOption.DESC)];

final channels = await client.queryChannels(
 filter: filter,
 sort: sort,
 watch: true,
 state: true,
).last;

channels.forEach((Channel c) {
 print("${c.extraData['name']} ${c.cid}");
});

$filter = ['members' => ['$in' => ['elon', 'jack', 'jessie'] ]];
$sort  = ['last_message_at' => 1]; // sorting direction (1 or -1)
$options = ['limit' => 10];

$channels = $client->queryChannels($filter,$sort,$options);

let controller = chatClient.channelListController(
  query: .init(
    filter: .and([.equal(.type, to: .messaging), .containMembers(userIds: ["thierry"])]),
    sort: [.init(key: .lastMessageAt, isAscending: false)],
    pageSize: 10
  )
)

controller.synchronize { error in
  if let error = error {
    // handle error
    print(error)
  } else {
    // access channels
    print(controller.channels)

    // load more if needed
    controller.loadNextChannels(limit: 10) { error in
      // handle error / access channels
    }
  }
}

const FFilter Filter = FFilter::And({
  FFilter::In(TEXT("members"), {TEXT("thierry")}),
  FFilter::Equal(TEXT("type"), TEXT("messaging")),
});
const TArray<FChannelSortOption> SortOptions{{EChannelSortField::LastMessageAt, ESortDirection::Descending}};
Client->QueryChannels(
  Filter,
  SortOptions,
  EChannelFlags::State,
  {},  // Pagination options
  [](const TArray<UChatChannel*> ReceivedChannels)
  {
    // Do something with ReceivedChannels
  });

resp, err := c.QueryChannels(ctx, &QueryOption{
	Filter: map[string]interface{}{
		"members": map[string]interface{}{
			"$in": []string{ "elon", "jack", "jessie" },
		},
	},
 Sort: []*SortOption{{Field: "last_message_at", Direction: 1}}, // sorting direction (1 or -1)
	Limit: 10,
})

client.query_channels(
 {"members": {"$in": ["elon", "jack", "jessie"]}},
 {"last_message_at": 1},
 limit=10,
)

client.query_channels({
 'members' => { '$in' => ['elon', 'jack', 'jessie'] } },
 sort: { 'last_message_at' => 1 },
 limit: 10
)

await channelClient.QueryChannelsAsync(QueryChannelsOptions.Default
.WithFilter(new Dictionary<string, object>
{
  { "members", new Dictionary<string, object> { { "$in", new[] {"elon", "jack", "jessie"} } } },
})
.WithSortBy(new SortParameter { Field = "last_message_at", Direction = SortDirection.Ascending })
.WithLimit(10));

var filters = new List<IFieldFilterRule>
{
  // Return only channels where local user is a member
  ChannelFilter.Members.In(Client.LocalUserData.UserId),
};

var channels = await Client.QueryChannelsAsync(filters);

// Android SDK
FilterObject filter = Filters.and(
    Filters.eq("type", "messaging"),
    Filters.in("members", Arrays.asList("thierry"))
);
int offset = 0;
int limit = 10;
QuerySortByField<Channel> sort = QuerySortByField.descByName("last_message_at");
int messageLimit = 0;
int memberLimit = 0;

QueryChannelsRequest request = new QueryChannelsRequest(filter, offset, limit, sort, messageLimit, memberLimit)
    .withWatch()
    .withState();

client.queryChannels(request).enqueue(result -> {
  if (result.isSuccess()) {
    List<Channel> channels = result.data();
  } else {
    // Handle result.error()
  }
});

// Backend SDK
Channel.list()
  .user(user)
  .filterCondition("type", "messaging")
  .filterConditions(FilterCondition.in("members", "thierry"))
  .sort(Sort.builder().field("last_message_at").direction(Direction.DESC).build())
  .watch(true)
  .state(true)
  .request()

Query Parameters

name	type	description	default
filters	object	The query filters to use. You can query on any of the custom fields you’ve defined on the Channel. You can also filter other built-in channel fields, see next section for reference.	{}
sort	object or array of objects	The sorting used for the channels matching the filters. Sorting is based on field and direction, multiple sorting options can be provided. You can sort based on last_updated, last_message_at,updated_at,created_at,member_count, unread_count or has_unread (unread status). Direction can be ascending (1) or descending (-1)	[{last_updated: -1}]
options	object	Query options. See below.	{}

Some languages does not guarantee field order in objects or maps. That’s why using array of single key objects is necessary

By default when query channels does not have any filter and it will match all channels on your application. While this might be OK during development, you most likely want to have at least some basic filtering.

At a minimum, the filter should include members: { $in: [userID] }.

The query channels endpoint will only return channels that the user can read, you should make sure that the query uses a filter that includes such logic. For example: messaging channels are readable only to their members, such requirement can be included in the query filter (see below).

Common filters by use-case

Messaging and Team

On messaging and team applications you normally have users added to channels as a member. A good starting point is to use this filter to show the channels the user is participating.

val filter = Filters.`in`("members", listOf("thierry"))

const filter = { members: { $in: ["thierry"] } };

final filter = Filter.and([
 Filter.equal('type', 'messaging'),
 Filter.in_('members', ['thierry']),
]);

$filter = ['members' => ['$in' => ['thierry'] ]];

let currentUserChannels = chatClient.channelListController(
  query: .init(
    filter: .containMembers(userIds: [chatClient.currentUserId!])
  )
)

currentUserChannels.synchronize()

// or

let thierryChannels = chatClient.channelListController(
  query: .init(
    filter: .containMembers(userIds: ["thierry"])
  )
)

thierryChannels.synchronize()

const FFilter Filter = FFilter::And({
  FFilter::In(TEXT("members"), {TEXT("thierry")}),
  FFilter::Equal(TEXT("type"), TEXT("messaging")),
});

filter := map[string]interface{}{
	"members": map[string]interface{}{
		"$in": []string{ "thierry" },
	},
}

filter = {"members": {"$in": ["thierry"]}}

filter = {"members" => {"$in" => ["thierry"]}}

var filter = new Dictionary<string, object>
{
  { "members", new Dictionary<string, object> { { "$in", new[] {"thierry"} } } },
}

// Android SDK
FilterObject filter = Filters.in("members", Arrays.asList("thierry"));

// Backend SDK
Map<String, Object> filter = FilterCondition.in("members", "thierry")

var filters = new List<IFieldFilterRule>
{
  // Return only channels where local user is a member
  ChannelFilter.Members.In(Client.LocalUserData.UserId),

  // You can define multiple filters that will all have to be satisfied
};

var channels = await Client.QueryChannelsAsync(filters);

Support

On a support chat, you probably want to attach additional information to channels such as the support agent handling the case and other information regarding the status of the support case (ie. open, pending, solved).

val filter = Filters.and(
  Filters.eq("agent_id", user.id),
  Filters.`in`("status", listOf("pending", "open", "new")),
)

const filter = {
  agent_id: `${user.Id}`,
  status: { $in: ["pending", "open", "new"] },
};

final filter = Filter.and([
 Filter.equal('agent_id', user.id),
 Filter.in_('status', ['pending', 'open', 'new']),
]);

final filter = Filter.and([
  Filter.equal('agent_id', '${user.id}'),
 Filter.in_('status', ['pending', 'open', 'new']),
]);

$filter = ['agent_id' => 'agent-id', 'status' => ['$in' => ['pending', 'open', 'new'] ]];

let channels = chatClient.channelListController(
  query: .init(
    filter: .and([.equal("agent_id", to: chatClient.currentUserId!), .in("status", values: ["pending", "open", "new"])])
  )
)

channels.synchronize()

const FFilter Filter = FFilter::And({
  FFilter::Equal(TEXT("agent_id"), User->Id),
  FFilter::In(TEXT("status"), {TEXT("pending"), TEXT("open"), TEXT("new")}),
});

filter := map[string]interface{}{
 "agent_id": user.Id,
	"status": map[string]interface{}{
		"$in": []string{ "pending", "open", "new" },
	},
}

filter = {
 "agent_id": user["id"],
 "status": {"$in": ["pending", "new", "open"]},
}

filter = {
 "agent_id" => user["id"],
 "status" => {"$in" => ["pending", "new", "open"]},
}

var filter = new Dictionary<string, object>
{
  { "agent_id", user.Id },
  { "status", new Dictionary<string, object> { { "$in", new[] {"pending", "new", "open"} } } },
}

// Android SDK
FilterObject filter = Filters.and(
    Filters.eq("agent_id", user.getId()),
    Filters.in("status", Arrays.asList("pending", "open", "new"))
);

// Backend SDK
Map<String, Object> filter = FilterCondition.and(
  FilterCondition.eq("agent_id", userID),
  FilterCondition.in("status", "pending", "open", "new")
);

var filters = new List<IFieldFilterRule>
{
  // Return only channels where local user is a member
  ChannelFilter.Custom("agent_id").EqualsTo(Client.LocalUserData.UserId),
  ChannelFilter.Custom("status").In("pending", "open", "new")
};

var channels = await Client.QueryChannelsAsync(filters);

Channel Queryable Built-In Fields

To learn more about the supported query operators themselves, please see: Query Syntax Operators.

The following channel fields can be used to filter your query results.

Name	Type	Description	Supported Operators	EXAMPLE
frozen	boolean	channel frozen status	$eq	false
type	string or list of string	the type of channel	$in, $eq	messaging
id	string or list of string	the ID of the channel	$in, $eq	general
cid	string or list of string	the full channel ID	$in, $eq	messaging:general
members	string or list of string	the list of user IDs of the channel members	$in, $eq	marcelo or [thierry, marcelo]
invite	string, must be one of these values: (pending, accepted, rejected)	the status of the invite	$eq	pending
joined	boolean	whether current user is joined the channel or not (through invite or directly)	$eq	true
muted	boolean	whether the current user has muted the channel	$eq	true
member.user.name	string	the ‘name’ property of a user who is a member of the channel	$autocomplete, $eq	marc
created_by_id	string	the id of the user that created the channel	$eq	marcelo
hidden	boolean	whether the current user has hidden the channel	$eq	false
last_message_at	string, must be formatted as an RFC3339 timestamp	the time of the last message in the channel	$eq, $gt, $lt, $gte, $lte, $exists	2021-01-15T09:30:20.45Z
member_count	integer	the number of members in the channel	$eq, $gt, $lt, $gte, $lte	5
created_at	string, must be formatted as an RFC3339 timestamp	the time the channel was created	$eq, $gt, $lt, $gte, $lte $exists	2021-01-15T09:30:20.45Z
updated_at	string, must be formatted as an RFC3339 timestamp	the time the channel was updated	$eq, $gt, $lt, $gte, $lte	2021-01-15T09:30:20.45Z
team	string	the team associated with the channel	$eq	stream
last_updated	string, must be formatted as an RFC3339 timestamp	the time of the last message in the channel. If the channel has no messages, then the time the channel was created	$eq, $gt, $lt, $gte, $lte	2021-01-15T09:30:20.45Z
Disabled	boolean	Whether the channel is disabled or not.	$eq	false
has_unread	boolean	Retrieve channels where the user has an unread message. Only “true” is supported, up to 100 channels	true	true

Querying by the channel Identifier should be done using the cid field as far as possible to optimize API performance. As the full channel ID, cid is indexed everywhere in Stream database where id is not.

Query Options

name	type	description	default	optional
state	boolean	if true returns the Channel state	true	✓
watch	boolean	if true listen to changes to this Channel in real time.	true	✓
limit	integer	The number of channels to return (max is 30)	10	✓
offset	integer	The offset (max is 1000)	0	✓
message_limit	integer	How many messages should be included to each channel (Max 300)	25	✓
member_limit	integer	How many members should be included for each channel (Max 100)	100	✓

Query channels allows you to retrieve channels and start watching them at same time using the watch parameter set to true.

Response

The result of querying a channel is a list of ChannelState objects which include all the required information to render them without any additional API call.

ChannelState Response

Field Name	Description
channel	The data for this channel
messages	The most recent messages for this channel (see message_limit option)
watcher_count	How many users are currently watching the channel
read	The read state for the members, up to 100 members, ordered by the most recent added, the current user’s read state is always included
members	The list of members, up to 100 ordered by the most recent added
pinned_messages	Up to 10 most recent pinned messages

[
  {
    "id": "f8IOxxbt",
    "type": "messaging",
    "cid": "messaging:f8IOxxbt",
    "last_message_at": "2020-01-10T07:26:46.791232Z",
    "created_at": "2020-01-10T07:25:37.63256Z",
    "updated_at": "2020-01-10T07:25:37.632561Z",
    "created_by": {
      "id": "8ce4c6e11118ca103a0a7c633dcf60dd",
      "role": "admin",
      "created_at": "2019-08-27T17:33:14.442265Z",
      "updated_at": "2020-01-10T07:25:36.402819Z",
      "last_active": "2020-01-10T07:25:36.395796Z",
      "banned": false,
      "online": false,
      "image": "https://ui-avatars.com/api/?name=mezie&size=192&background=000000&color=6E7FFE&length=1",
      "name": "mezie",
      "username": "mezie"
    },
    "frozen": false,
    "config": {
      "created_at": "2020-01-20T10:23:44.878185331Z",
      "updated_at": "2020-01-20T10:23:44.878185458Z",
      "name": "messaging",
      "typing_events": true,
      "read_events": true,
      "connect_events": true,
      "search": true,
      "reactions": true,
      "replies": true,
      "mutes": true,
      "uploads": true,
      "url_enrichment": true,
      "max_message_length": 5000,
      "automod": "disabled",
      "automod_behavior": "flag",
      "commands": [
        {
          "name": "giphy",
          "description": "Post a random gif to the channel",
          "args": "[text]",
          "set": "fun_set"
        }
      ]
    },
    "name": "Video Call"
  }
]

Pagination

Query channel requests can be paginated similar to how you paginate on other calls. Here’s a short example:

// Get the first 10 channels
val filter = Filters.`in`("members", "thierry")
val offset = 0
val limit = 10
val request = QueryChannelsRequest(filter, offset, limit)
client.queryChannels(request).enqueue { result ->
  if (result.isSuccess) {
    val channels = result.data()
  } else {
    // Handle result.error()
  }
}

// Get the second 10 channels
val nextRequest = QueryChannelsRequest(
  filter = filter,
  offset = 10, // Skips first 10
  limit = limit
)
client.queryChannels(nextRequest).enqueue { result ->
  if (result.isSuccess) {
    val channels = result.data()
  } else {
    // Handle result.error()
  }
}

// retrieve 20 channels with Thierry as a member and skip first 10

const filter = { members: { $in: ["thierry"] } };
const sort = { last_message_at: -1 };

const channels = await authClient.queryChannels(filter, sort, {
  limit: 20,
  offset: 10,
});

// retrieve 20 channels with Thierry as a member and skip first 10

final filter = Filter.in_('members', ['thierry']);

final sort = [SortOption("last_message_at", direction: SortOption.DESC)];

final response = await client.queryChannels(
 filter: filter,
 sort: sort,
 paginationParams: PaginationParams(
  limit: 20,
  offset: 10,
 ),
);

response.first.forEach((ChannelState f) {
 print("${f.channel.extraData['name']} ${f.channel.cid}");
});

// retrieve 20 channels with Thierry as a member and skip first 10
$filter = ['members' => ['$in' => ['thierry'] ]];
$sort  = ['last_message_at' => -1]; // sorting direction (1 or -1)
$options = ['limit' => 20, 'offset' => 10];

$channels = $client->queryChannels($filter,$sort,$options);

let controller = chatClient.channelListController(
  query: .init(
    filter: .containMembers(userIds: ["thierry"]),
    pageSize: 10
  )
)

// Get the first 10 channels
controller.synchronize { error in
  if let error = error {
    // handle error
    print(error)
  } else {
    // Access channels
    print(controller.channels)

    // Get the next 10 channels
    controller.loadNextChannels { error in
      // handle error / access channels
      print(error ?? controller.channels)
    }
  }
}

const FFilter Filter = FFilter::In(TEXT("members"), {TEXT("thierry")});
const TArray<FChannelSortOption> SortOptions{
  {EChannelSortField::LastMessageAt, ESortDirection::Descending},
};
const FPaginationOptions PaginationOptions{
  20,  // Limit
  10,  // Offset
};
Client->QueryChannels(
  Filter,
  SortOptions,
  EChannelFlags::State,
  PaginationOptions,
  [](const TArray<UChatChannel*> ReceivedChannels)
  {
    // Started watching channels
  });

// retrieve 20 channels with Thierry as a member and skip first 10
resp, err := c.QueryChannels(ctx, &QueryOption{
	Filter: map[string]interface{}{
		"members": map[string]interface{}{
			"$in": []string{ "thierry" },
		},
	},
 Sort: []*SortOption{{Field: "last_message_at", Direction: -1}}, // sorting direction (1 or -1)
	Limit: 20,
	Offset: 10,
})

# retrieve 20 channels with Thierry as a member and skip first 10
client.query_channels(
 {"members": {"$in": ["thierry"]}},
 {"last_message_at": -1},
 limit=20,
 offset=10,
)

# retrieve 20 channels with Thierry as a member and skip first 10
client.query_channels({
 'members' => { '$in' => ['thierry'] } },
 sort: { 'last_message_at' => -1 },
 limit: 20,
 offset: 10,
)

await channelClient.QueryChannelsAsync(QueryChannelsOptions.Default
.WithFilter(new Dictionary<string, object>
{
  { "members", new Dictionary<string, object> { { "$in", new[] {"thierry"} } } },
})
.WithSortBy(new SortParameter { Field = "last_message_at", Direction = SortDirection.Descending })
.WithLimit(20)
.WithOffset(10);

// Android SDK

// Get the first 10 channels
FilterObject filter = Filters.in("members", "thierry");
int offset = 0;
int limit = 10;
QuerySorter<Channel> sort = new QuerySortByField<>();
int messageLimit = 0;
int memberLimit = 0;
QueryChannelsRequest request = new QueryChannelsRequest(filter, offset, limit, sort, messageLimit, memberLimit);

client.queryChannels(request).enqueue(result -> {
  if (result.isSuccess()) {
    List<Channel> channels = result.data();
  } else {
    // Handle result.error()
  }
});

// Get the second 10 channels
int nextOffset = 10; // Skips first 10
QueryChannelsRequest nextRequest = new QueryChannelsRequest(filter, nextOffset, limit, sort, messageLimit, memberLimit);
client.queryChannels(nextRequest).enqueue(result -> {
  if (result.isSuccess()) {
    List<Channel> channels = result.data();
  } else {
    // Handle result.error()
  }
});

// Backend SDK
// Get first 10 channels
Map<String, Object> filter = FilterCondition.in("members", "thierry");

Integer offset = 0;
Integer limit = 10;
Integer messageLimit = 0;
Integer memberLimit = 0;

ChannelListRequest req = Channel.list()
  .user(testUserRequestObject)
  .filterConditions(filter)
  .watch(true)
  .state(true)
  .messageLimit(0)
  .memberLimit(0)

ChannelListResponse channels = req.limit(limit).offset(offset).request();

// Get the second 10 channels
Integer nextOffset = 10;
ChannelListResponse nextChannels = req.limit(limit).offset(nextOffset).request();

var filters = new List<IFieldFilterRule>
{
  // Return only channels where local user is a member
  ChannelFilter.Members.In(Client.LocalUserData.UserId),

  // You can define multiple filters that will all have to be satisfied
};

// Pass limit and offset to control the page or results returned
// Limit - how many records per page
// Offset - how many records to skip
var channels = await Client.QueryChannelsAsync(filters, limit: 30, offset: 60);

It is important to note that your filter should include, at the very least {members: {$in: [userID]} or pagination could break.

Updating Channel Members

Querying Members