Activity Feeds V3 is in closed alpha — do not use it in production (just yet).

Feeds

Creating a Feed

// Feed with no extra fields, of feed group "user"
let feed = client.feed(group: "user", id: "john")
try await feed.getOrCreate()

// More options
let query = FeedQuery(
    group: "user",
    id: "jack",
    data: .init(
        description: "My personal feed",
        name: "jack",
        visibility: "public"
    )
)
let feed2 = client.feed(for: query)
try await feed.getOrCreate()

Reading a Feed

Here is a basic example of how to read a feed:

let feed = client.feed(group: "user", id: "john")
try await feed.getOrCreate()
let feedData = feed.state.feed
let activities = feed.state.activities
let members = feed.state.members

The response will contain the following data.

You have more options when reading a feed, let’s go over a few:

let query = FeedQuery(
    group: "user",
    id: "john",
    activityFilter: .in(.filterTags, ["green"]), // filter activities with filter tag green
    activityLimit: 10,
    externalRanking: ["user_score": 0.8], // additional data used for ranking
    followerLimit: 10,
    followingLimit: 10,
    memberLimit: 10,
    view: "myview", // overwrite the default ranking or aggregation logic for this feed. good for split testing
    watch: true // receive web-socket events with real-time updates
)
let feed = client.feed(for: query)
try await feed.getOrCreate()
let activities = feed.state.activities
let feedData = feed.state.feed

Feed Pagination

Here is how you can read the next page on the feed:

let feed = client.feed(
    for: .init(
        group: "user",
        id: "john",
        activityLimit: 10
    )
)
// Page 1
try await feed.getOrCreate()
let activities = feed.state.activities // First 10 activities

// Page 2
let page2Activities = try await feed.queryMoreActivities(limit: 10)

let page1And2Activities = feed.state.activities

Filtering Examples

Another common use case is filtering a feed. This is trickier than it seems. Keep in mind that for performance reasons feeds often have to be computed on write time. To allow for filtering we expose the following API.

// Add a few activities
let fid = FeedId(group: "user", id: "john")
try await client.upsertActivities([
    ActivityRequest(fids: [fid.rawValue], filterTags: ["green", "blue"], text: "first", type: "post"),
    ActivityRequest(fids: [fid.rawValue], filterTags: ["yellow", "blue"], text: "second", type: "post"),
    ActivityRequest(fids: [fid.rawValue], filterTags: ["orange"], text: "third", type: "post"),
])
// Now read the feed, this will fetch activity 1 and 2
let query = FeedQuery(fid: fid, activityFilter: .in(.filterTags, value: ["blue"]))
let feed = client.feed(for: query)
try await feed.getOrCreate()
let activities = feed.state.activities // contains first and second

The filter syntax also supports $or and $and, so here’s an example that’s a little more complicated:

// Get all the activities where tags contain "green" and type is "post" or tag contains "orange" and type is "activity"
let query = FeedQuery(
    group: "user",
    id: "john",
    activityFilter: .or([
        .and([
            .in(.filterTags, ["green"]),
            .equal(.type, "post"),
        ]),
        .and([
            .in(.filterTags, ["orange"]),
            .equal(.type, "activity")
        ])
    ])
)
try await feed.getOrCreate()
let activities = feed.state.activities

Feed Members

You can add and remove members to a feed. This is useful for building communities where a set of users can add content to the feed.

// The following methods are available to edit the members of a feed
try await feed.updateFeedMembers(
    request: .init(
        members: [.init(
            custom: ["joined": "2024-01-01"],
            role: "moderator",
            userId: "john"
        )],
        operation: .upsert
    )
)
// Remove members
try await feed.updateFeedMembers(
    request: .init(
        members: [.init(userId: "john"), .init(userId: "jane")],
        operation: .remove
    )
)
// Set members (overwrites the list)
try await feed.updateFeedMembers(
    request: .init(
        members: [.init(role: "moderator", userId: "john")],
        operation: .set
    )
)

Member invites

You can invite members with the invite flag, where invited users can accept or reject the membership.

// Request to become a member
try await feed.updateFeedMembers(
    request: .init(
        members: [.init(
            custom: ["reason": "community builder"],
            invite: true,
            role: "moderator",
            userId: "john"
        )],
        operation: .upsert
    )
)
// Accept and reject member requests
_ = try await feed.acceptFeedMember()
_ = try await feed.rejectFeedMember()

Query Feeds

Querying feeds allows you to do things like showing the list of communities you’ve joined.

Here’s an example of how to query feeds:

Querying My Feeds

let query = FeedsQuery(
    filter: .equal(.createdById, "john"),
    sort: [Sort(field: .createdAt, direction: .reverse)],
    limit: 10,
    watch: true
)
let feedList = client.feedList(for: query)
// Page 1
let page1 = try await feedList.get()

// Page 2
let page2 = try await feedList.queryMoreFeeds(limit: 10)

let page1And2 = feedList.state.feeds

Querying Feeds Where I Am a Member

let query = FeedsQuery(
    filter: .contains(.members, "john")
)
let feedList = client.feedList(for: query)
let feeds = try await feedList.get()

Querying feeds by name or description

let sportsQuery = FeedsQuery(
    filter: .and([
        .equal(.visibility, "public"),
        .query(.name, "Sports")
    ])
)
let sportsFeedList = client.feedList(for: sportsQuery)
let sportsFeeds = try await sportsFeedList.get()

let techQuery = FeedsQuery(
    filter: .and([
        .equal(.visibility, "public"),
        .autocomplete(.description, "tech")
    ])
)
let techFeedList = client.feedList(for: techQuery)
let techFeeds = try await techFeedList.get()

Querying feeds by creator name

let query = FeedsQuery(
    filter: .and([
        .equal(.visibility, "public"),
        .query(.createdByName, "Thompson")
    ])
)
let feedList = client.feedList(for: query)
let feeds = try await feedList.get()

Feeds Queryable Built-in Fields

nametypedescriptionsupported operationsexample
idstring or list of stringsThe ID of the feed$in, $eq{ id: { $in: [ 'abc', 'xyz' ] } }
group_idstring or list of stringsThe ID of the group this feed belongs to$in, $eq{ group_id: { $in: [ 'abc', 'xyz' ] } }
fidstring or list of stringsThe fully qualified feed ID (group_id:id)$in, $eq{ fid: { $in: [ 'abc', 'xyz' ] } }
visibilitystring or list of stringsThe visibility setting of the feed$in, $eq{ visibility: { $eq: 'public' } }
created_by_idstring or list of stringsThe ID of the user who created the feed$in, $eq{ created_by_id: { $in: [ 'abc', 'xyz' ] } }
created_by.namestringThe name of the user who created the feed$eq, $q, $autocomplete{ 'created_by.name': { $autocomplete: 'Frank' } }
namestringThe name of the feed$eq, $q, $autocomplete{ name: { $q: 'Sports' } }
descriptionstringThe description of the feed$eq, $q, $autocomplete{ description: { $autocomplete: 'tech' } }
member_countnumberThe number of members in this feed$eq, $ne, $gt, $lt, $gte, $lte{ member_count: { $gt: 100 } }
memberslist of stringsThe list of members in this feed$in{ members: { $in: [ 'bob', 'alice' ] } }
following_countnumberThe number of feeds this feed follows$eq, $ne, $gt, $lt, $gte, $lte{ following_count: { $gt: 100 } }
following_feedslist of stringsThe list of feeds this feed follows$in{ following_feeds: { $in: [ 'feed1', 'feed2' ] } }
follower_countnumberThe number of followers of this feed$eq, $ne, $gt, $lt, $gte, $lte{ follower_count: { $gt: 100 } }
created_atstring, RFC3339 timestampThe time the feed was created$eq, $gt, $lt, $gte, $lte{ created_at: { $gte: '2023-12-04T09:30:20.45Z' } }
updated_atstring, RFC3339 timestampThe time the feed was updated$eq, $gt, $lt, $gte, $lte{ updated_at: { $gte: '2023-12-04T09:30:20.45Z' } }

Feeds can be sorted by created_at, updated_at, member_count, follower_count, and following_count.

Be sure to reach out to support if you need additional query feed capabilities.

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