feat: address comments and change update user share behaviour

Author: bangyro

CHANGELOG.md

@@ -26,10 +26,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - Add a new field `mutable_flag` to `FeeVault` to indicate its mutability
-- Add a new field `operator` to `FeeVault`. The `operator` and vault owner can perform admin instructions on mutable `FeeVault`
+- Add a new field `operator` to `FeeVault`. The `operator` and vault owner can perform operator instructions on mutable `FeeVault`
 - Add a new owner endpoint `update_operator` for vault owner to update the operator field
-- Add a new admin endpoint `remove_user` which removes a user and distributes their unclaimed fees proportionally based on the remaining users' share
-- Add a new admin endpoint `update_user_share` to update a user's share. This affects the fees the user will be entitled to when the vault is funded. Any fees users earned before the share changed will be preserved
+- Add a new operator endpoint `remove_user` which removes a user and transfers any unclaimed fee into an account for the removed user to claim
+- Add a new endpoint `claim_removed_user_fee` where a user who have been removed from the `FeeVault` can claim any unclaimed fees
+- Add a new operator endpoint `update_user_share` to update a user's share. This affects the fees the user will be entitled to when the vault is funded. Any fees users earned before the share changed will be preserved
 
 ## dynamic-fee-sharing [0.1.1] [PR #8](https://github.com/MeteoraAg/dynamic-fee-sharing/pull/8)
 

Cargo.toml

@@ -14,6 +14,6 @@ incremental = false
 codegen-units = 1
 
 [workspace.dependencies]
-anchor-lang = {version = "0.31.1", features = ["event-cpi"]}
+anchor-lang = {version = "0.31.1", features = ["event-cpi", "init-if-needed"]}
 anchor-spl = "0.31.1"
 bytemuck = { version = "1.20.0", features = ["derive", "min_const_generics"] }

programs/dynamic-fee-sharing/src/constants.rs

@@ -9,6 +9,7 @@ pub mod seeds {
     pub const FEE_VAULT_PREFIX: &[u8] = b"fee_vault";
     pub const FEE_VAULT_AUTHORITY_PREFIX: &[u8] = b"fee_vault_authority";
     pub const TOKEN_VAULT_PREFIX: &[u8] = b"token_vault";
+    pub const REMOVED_USER_TOKEN_VAULT: &[u8] = b"removed_user_token_vault";
 }
 
 // (program_id, instruction, index_of_token_vault_account)

programs/dynamic-fee-sharing/src/event.rs

@@ -31,12 +31,20 @@ pub struct EvtClaimFee {
 #[event]
 pub struct EvtUpdateUserShare {
     pub fee_vault: Pubkey,
-    pub index: u8,
+    pub user: Pubkey,
     pub share: u32,
 }
 
 #[event]
 pub struct EvtRemoveUser {
     pub fee_vault: Pubkey,
     pub user: Pubkey,
+    pub unclaimed_fee: u64,
+}
+
+#[event]
+pub struct EvtClaimRemovedUserFee {
+    pub fee_vault: Pubkey,
+    pub user: Pubkey,
+    pub claimed_fee: u64,
 }

programs/dynamic-fee-sharing/src/instructions/admin/ix_remove_user.rs

@@ -0,0 +1,85 @@
+use crate::const_pda;
+use crate::constants::seeds::REMOVED_USER_TOKEN_VAULT;
+use crate::event::EvtClaimRemovedUserFee;
+use crate::state::FeeVault;
+use crate::utils::token::transfer_from_fee_vault;
+use anchor_lang::prelude::*;
+use anchor_spl::token_interface::{
+    close_account, CloseAccount, Mint, TokenAccount, TokenInterface,
+};
+
+#[event_cpi]
+#[derive(Accounts)]
+pub struct ClaimRemovedUserFeeCtx<'info> {
+    #[account(has_one = token_mint, has_one = owner)]
+    pub fee_vault: AccountLoader<'info, FeeVault>,
+
+    /// CHECK: fee vault authority
+    #[account(address = const_pda::fee_vault_authority::ID)]
+    pub fee_vault_authority: UncheckedAccount<'info>,
+
+    pub token_mint: Box<InterfaceAccount<'info, Mint>>,
+
+    #[account(
+        mut,
+        seeds = [
+            REMOVED_USER_TOKEN_VAULT,
+            fee_vault.key().as_ref(),
+            token_mint.key().as_ref(),
+            user.key().as_ref(),
+        ],
+        bump,
+        token::mint = token_mint,
+        token::authority = fee_vault_authority,
+    )]
+    pub removed_user_token_vault: Box<InterfaceAccount<'info, TokenAccount>>,
+
+    #[account(
+        mut, 
+        token::authority = user, 
+        token::mint = token_mint,
+    )]
+    pub user_token_vault: Box<InterfaceAccount<'info, TokenAccount>>,
+
+    /// CHECK: fee vault owner, receives rent from closed account
+    #[account(mut)]
+    pub owner: UncheckedAccount<'info>,
+
+    pub user: Signer<'info>,
+
+    pub token_program: Interface<'info, TokenInterface>,
+}
+
+pub fn handle_claim_removed_user_fee(ctx: Context<ClaimRemovedUserFeeCtx>) -> Result<()> {
+    let fee_being_claimed = ctx.accounts.removed_user_token_vault.amount;
+
+    if fee_being_claimed > 0 {
+        transfer_from_fee_vault(
+            ctx.accounts.fee_vault_authority.to_account_info(),
+            &ctx.accounts.token_mint,
+            &ctx.accounts.removed_user_token_vault,
+            &ctx.accounts.user_token_vault,
+            &ctx.accounts.token_program,
+            fee_being_claimed,
+        )?;
+    }
+
+    let signer_seeds = fee_vault_authority_seeds!();
+    close_account(CpiContext::new_with_signer(
+        ctx.accounts.token_program.to_account_info(),
+        CloseAccount {
+            account: ctx.accounts.removed_user_token_vault.to_account_info(),
+            destination: ctx.accounts.owner.to_account_info(),
+            authority: ctx.accounts.fee_vault_authority.to_account_info(),
+        },
+        &[&signer_seeds[..]],
+    ))?;
+
+    emit_cpi!(EvtClaimRemovedUserFee {
+        fee_vault: ctx.accounts.fee_vault.key(),
+        user: ctx.accounts.user.key(),
+        claimed_fee: fee_being_claimed,
+    });
+
+    Ok(())
+}

programs/dynamic-fee-sharing/src/instructions/ix_claim_removed_user_fee.rs

@@ -13,7 +13,7 @@ use anchor_spl::token_interface::{Mint, TokenAccount, TokenInterface};
 #[derive(AnchorSerialize, AnchorDeserialize, Debug, Clone)]
 pub struct InitializeFeeVaultParameters {
     pub padding: [u8; 63], // for future use
-    pub mutable_flag: u8,
+    pub mutable_flag: bool,
     pub users: Vec<UserShare>,
 }
 
@@ -40,10 +40,6 @@ impl InitializeFeeVaultParameters {
                 FeeVaultError::InvalidUserAddress
             );
         }
-        require!(
-            self.mutable_flag == 0 || self.mutable_flag == 1,
-            FeeVaultError::InvalidFeeVaultParameters
-        );
         // that is fine to leave user addresses are duplicated?
         Ok(())
     }
@@ -113,7 +109,7 @@ pub fn handle_initialize_fee_vault(
         &Pubkey::default(),
         0,
         FeeVaultType::NonPdaAccount.into(),
-        params.mutable_flag,
+        params.mutable_flag.into(),
     )?;
 
     emit_cpi!(EvtInitializeFeeVault {

programs/dynamic-fee-sharing/src/instructions/ix_initialize_fee_vault.rs

@@ -80,7 +80,7 @@ pub fn handle_initialize_fee_vault_pda(
         &ctx.accounts.base.key,
         ctx.bumps.fee_vault,
         FeeVaultType::PdaAccount.into(),
-        params.mutable_flag,
+        params.mutable_flag.into(),
     )?;
 
     emit_cpi!(EvtInitializeFeeVault {

programs/dynamic-fee-sharing/src/instructions/ix_initialize_fee_vault_pda.rs

@@ -8,7 +8,9 @@ pub mod ix_initialize_fee_vault_pda;
 pub use ix_initialize_fee_vault_pda::*;
 pub mod ix_fund_by_claiming_fee;
 pub use ix_fund_by_claiming_fee::*;
-pub mod admin;
-pub use admin::*;
+pub mod ix_claim_removed_user_fee;
+pub use ix_claim_removed_user_fee::*;
+pub mod operator;
+pub use operator::*;
 pub mod owner;
 pub use owner::*;

programs/dynamic-fee-sharing/src/instructions/mod.rs

@@ -0,0 +1,72 @@
+use crate::const_pda;
+use crate::constants::seeds::REMOVED_USER_TOKEN_VAULT;
+use crate::event::EvtRemoveUser;
+use crate::state::FeeVault;
+use crate::utils::token::transfer_from_fee_vault;
+use anchor_lang::prelude::*;
+use anchor_spl::token_interface::{Mint, TokenAccount, TokenInterface};
+
+#[event_cpi]
+#[derive(Accounts)]
+pub struct RemoveUserCtx<'info> {
+    #[account(mut, has_one = token_vault, has_one = token_mint)]
+    pub fee_vault: AccountLoader<'info, FeeVault>,
+
+    /// CHECK: fee vault authority
+    #[account(address = const_pda::fee_vault_authority::ID)]
+    pub fee_vault_authority: UncheckedAccount<'info>,
+
+    #[account(mut)]
+    pub token_vault: Box<InterfaceAccount<'info, TokenAccount>>,
+
+    pub token_mint: Box<InterfaceAccount<'info, Mint>>,
+
+    /// CHECK: the user being removed
+    pub user: UncheckedAccount<'info>,
+
+    #[account(
+        init_if_needed,
+        payer = signer,
+        seeds = [
+            REMOVED_USER_TOKEN_VAULT,
+            fee_vault.key().as_ref(),
+            token_mint.key().as_ref(),
+            user.key().as_ref(),
+        ],
+        bump,
+        token::mint = token_mint,
+        token::authority = fee_vault_authority,
+    )]
+    pub removed_user_token_vault: Box<InterfaceAccount<'info, TokenAccount>>,
+
+    #[account(mut)]
+    pub signer: Signer<'info>,
+
+    pub token_program: Interface<'info, TokenInterface>,
+    pub system_program: Program<'info, System>,
+}
+
+pub fn handle_remove_user(ctx: Context<RemoveUserCtx>) -> Result<()> {
+    let mut fee_vault = ctx.accounts.fee_vault.load_mut()?;
+    let user = ctx.accounts.user.key();
+    let unclaimed_fee = fee_vault.validate_and_remove_user_and_get_unclaimed_fee(&user)?;
+
+    if unclaimed_fee > 0 {
+        transfer_from_fee_vault(
+            ctx.accounts.fee_vault_authority.to_account_info(),
+            &ctx.accounts.token_mint,
+            &ctx.accounts.token_vault,
+            &ctx.accounts.removed_user_token_vault,
+            &ctx.accounts.token_program,
+            unclaimed_fee,
+        )?;
+    }
+
+    emit_cpi!(EvtRemoveUser {
+        fee_vault: ctx.accounts.fee_vault.key(),
+        user,
+        unclaimed_fee,
+    });
+
+    Ok(())
+}