FIP: Farcaster Pro

[aditiharini]

Title: Farcaster Pro
Type: Implementation FIP
Authors: @aditiharini, @sanjayprabhu, @horsefacts, @danromero

Abstract

Introduce the concept of a users with pro tier subscriptions. Users with active pro tier subscriptions have access to extra protocol level features.

Specification

Contract

Farcaster pro tier subscriptions will be paid for through a the TierRegistry contract which be deployed on Base mainnet and will emit events that Snapchain reads and stores. The design of the contract and the events allows for adding more tiers in the future with different pricing and a different set of associated features.

Subscriptions are purchased for a period of time. If time is purchased while a user already has an active subscription, the new time will be added to the time when the existing subscription expires. If there is no existing subscription, the subscription will start from block timestamp where the purchase was recorded.

enum OnChainEventType {
  EVENT_TYPE_NONE = 0;
  EVENT_TYPE_SIGNER = 1;
  EVENT_TYPE_SIGNER_MIGRATED = 2;
  EVENT_TYPE_ID_REGISTER = 3;
  EVENT_TYPE_STORAGE_RENT = 4;
  + EVENT_TYPE_TIER_PURCHASE = 5;
}

enum TierType {
  None = 0;
  Pro = 1;
}

message TierPurchaseBody {
  TierType tier_type = 1;
  uint64 for_days = 2;
  bytes payer = 3;
}

message OnChainEvent {
  ...
  oneof body {
    SignerEventBody signer_event_body = 9;
    SignerMigratedEventBody signer_migrated_event_body = 10;
    IdRegisterEventBody id_register_event_body = 11;
    StorageRentEventBody storage_rent_event_body = 12;
    + TierPurchaseBody tier_purchase_event_body = 15;
  }
}

New protocol features

There are 3 protocol features which will be enabled for pro tier users.

10k Length Casts

The protocol will accept casts up to 10k characters for users with a pro subscription. To support this new type of cast, there is a new CastType in the protocol. Casts that are >1024 characters must be tagged with type = CastType.TEN_K_CAST. Users without the pro subscription will still be able to post casts up to 1024 characters.

enum CastType {
  CAST = 0;
  LONG_CAST = 1;
  + TEN_K_CAST = 2;
}

4 embeds

The protocol will accept 4 embeds of any kind for users with a pro subscription. Users without a pro tier subscription will still be able to post casts with up to 2 embeds.

Banners

The protocol will accept UserData messages with values ≤ 256 characters in length with type = USER_DATA_TYPE_BANNER for users with a pro tier subscription. Values should point to images which will be displayed as the user’s banner image. A user may only have 1 banner image at any point in time as per the rules for the UserData set.

enum UserDataType {
  USER_DATA_TYPE_NONE = 0;
  USER_DATA_TYPE_PFP = 1; // Profile Picture for the user
  USER_DATA_TYPE_DISPLAY = 2; // Display Name for the user
  USER_DATA_TYPE_BIO = 3; // Bio for the user
  USER_DATA_TYPE_URL = 5; // URL of the user
  USER_DATA_TYPE_USERNAME = 6; // Preferred Name for the user
  USER_DATA_TYPE_LOCATION = 7; // Current location for the user
  USER_DATA_TYPE_TWITTER = 8; // Username of user on twitter
  USER_DATA_TYPE_GITHUB = 9; // Username of user on github
  + USER_DATA_TYPE_BANNER = 10; // Banner image for the user
}

Storage

Expiring subscriptions

After a user’s pro tier subscription expires, they will no longer be able to post content only available to pro tier users. The data they generated as a pro tier user will NOT be revoked or erased. If the user happens to exceed their storage limits in the future, their oldest data from the relevant set will be pruned as per the existing pruning logic.

Storage units are orthogonal to tier subscriptions

The pro tier subscription does not currently guarantee users extra storage. Storage units are purchased and tracked entirely independently. Long casts and casts with extra embeds will count the same as regular casts toward storage limits.

Read API updates

The GetCurrentStorageLimitsByFid endpoint will be updated to return when a user’s pro tier subscription expires. If the user hasn’t purchased a subscription, the API will return an entry for the pro tier with expires_at = 0.

message TierDetails {
  TierType tier_type = 1;
  uint64 expires_at = 2;
}
message StorageLimitsResponse {
  repeated StorageLimit limits = 1;
  uint32 units = 2;
  repeated StorageUnitDetails unit_details = 3;
  + repeated TierDetails tier_subscriptions = 4;
}

Release

This change requires a protocol upgrade. Nodes will be updated to support the new protocol features the week of June 9th . Pro tier subscriptions will not be tracked on the protocol and new protocol features will not be available until June 16, when the new protocol version goes live.

[Ghanijaan]

Nice 👍 FIP

[Siddxa]

It is certainly very strange that users with pro accounts do not receive extended storage.

[ozan-demir-dev]

Mrb

[YUBTC]

very good