[fungible_asset] a layered design #7183

lightmark · 2023-03-15T22:00:14Z

Description

This defines fungibility or a fungible asset in Aptos Move.

At the core is an asset object equipped with FungibleSource that defines asset metadata(fixed supply only for now) and during creation provides minting, burning, and freezing capabilities. So FungibleSource entitles an asset object with fungibility.
A FungibleSource's mint, burn, and freeze capabilities manage FungibleAssets, which contain a balance and point back to the originating asset object that has FungibleSource.

As an example, this also introduces a ManagedFungibleSource that enables the owner of the asset object with fungible source to mint, burn, and freeze these FungibleAssets.

Test Plan

unit test.

lightmark · 2023-03-15T22:02:05Z

aptos-move/framework/aptos-framework/sources/create_signer.move

@@ -15,5 +15,5 @@ module aptos_framework::create_signer {
    friend aptos_framework::multisig_account;
    friend aptos_framework::object;

-    public(friend) native fun create_signer(addr: address): signer;
+    public native fun create_signer(addr: address): signer;


Please ignore for now but I need this for the creation of FungibleAssetIndex and FungibleAsset object with deposit from nowhere.

I suppose we'll merge this package into AptosFramework sooner or later so it's okay to use this function.

I'm not sure why we need to share the signer... if we jump to this, we're missing a permissions model.

I don't think we are missing the permission model. I don't mean this is the final change. It is just a hack for me to test. The way we jump to this is:

make FA module in the framework.

friend FA module here and keeep public(friend)

I need this to create a FA object from nowhere when getting money the first time. It's for unilateral transfer.

In general, to create a new object we need a signer. When we're sending coins to someone for the first time and they don't have the object to store them, there's not a perfect signer to use (using sender's signer can be strange)

davidiw

amazing, amazing

davidiw · 2023-03-16T06:06:53Z

aptos-move/framework/aptos-framework/sources/create_signer.move

@@ -15,5 +15,5 @@ module aptos_framework::create_signer {
    friend aptos_framework::multisig_account;
    friend aptos_framework::object;

-    public(friend) native fun create_signer(addr: address): signer;
+    public native fun create_signer(addr: address): signer;


I'm not sure why we need to share the signer... if we jump to this, we're missing a permissions model.

aptos-move/move-examples/fungible_asset/sources/coin_example.move

aptos-move/move-examples/fungible_asset/sources/fungible_asset.move

aptos-move/move-examples/fungible_asset/sources/fungible_source.move

davidiw · 2023-03-16T06:36:52Z

aptos-move/move-examples/fungible_asset/sources/fungible_source.move

+    /// Mint the `amount` of coin with MintCap.
+    public fun mint_with_cap<T: key>(
+        cap: &MintCap,
+        asset: &Object<T>,


the cap should sufficiently define the asset, no need for both or we have an issue.

maybe we should call this mint_into?
how does one create a new object, can anyone do that? I need to read more.

only the create_signer I hacked can create a new FA object... But you dislike it for no reason :(

Option 1) Use the extendref that comes with the source, option 2) pass in the entity who will own the object.

That totally breaks the current code structure. Because when you deposit a hot potato FA into my account, you don't want me to provide my signer. This blocks unilateral sending.

aptos-move/move-examples/fungible_asset/sources/managed_fungible_asset.move

aptos-move/move-examples/fungible_asset/sources/fungible_source.move

aptos-move/move-examples/fungible_asset/sources/managed_fungible_asset.move

aptos-move/move-examples/fungible_asset/sources/fungible_source.move

aptos-move/move-examples/fungible_asset/sources/coin_example.move

aptos-move/move-examples/fungible_asset/sources/managed_fungible_asset.move

aptos-move/move-examples/fungible_asset/sources/fungible_source.move

aptos-move/move-examples/fungible_asset/sources/coin_example.move

lightmark · 2023-03-17T22:13:51Z

3 questions to answer:

how to create object from nowhere, use create_signer from framework?
do we want to delete the PinnedFungibleAsset Object if the balance depletes? (omg I hate this name...~)
how to deal with coin? My feeling is we may want to do what I showed in node_code_coin.move

aptos-move/move-examples/fungible_asset/sources/fungible_asset.move

davidiw · 2023-03-20T00:40:51Z

aptos-move/move-examples/fungible_asset/sources/fungible_asset.move

+    /// Freeeze/unfreeze any account of asset address `asset_addr`.
+    public(friend) fun set_frozen_flag(
+        fungible_asset_owner: address,
+        asset_addr: address,
+        frozen: bool
+    ) acquires FungibleAssetStore, PinnedFungibleAsset {
+        let pfa_opt = get_pinned_fungible_asset_object(fungible_asset_owner, asset_addr, true);
+        let pfa = option::destroy_some(pfa_opt);
+        borrow_global_mut<PinnedFungibleAsset>(object_address(&pfa)).frozen = frozen;
+    }


we're going down a dangerous path here, we should push the concept of the TransferRef into here rather than re-invent.. then fungible assets could determine what it means to freeze, enable allowlists, partial freeze, approvals, etc.

I understand what you mean here. But it is really mind-blowing that how to offer the flexibility of all the features you mentioned here. lemme think about it.

Don't overthink it, we already have the TransferRef pattern and ungated transfers, just replicate it :)

only for partial freeze. I am confused that how transferRef pattern deal with this case.

davidiw

I think we should merge fungible_caps, fungible_source, and fungible_assets. I'm happy to contribute!

davidiw · 2023-03-22T00:55:13Z

aptos-move/framework/aptos-framework/sources/fungible_asset/fungible_asset.move

+    #[test_only]
+    use aptos_framework::fungible_source::init_test_fungible_source;


let's be consistent here and have this where it is used and we're importing a function 😭

davidiw · 2023-03-22T01:36:18Z

aptos-move/framework/aptos-framework/sources/fungible_asset/fungible_asset.move

+        balance: u64,
+        /// Fungible Assets transferring is a common operation, this allows for disabling and enabling
+        /// transfers bypassing the use of a TransferCap.
+        allow_ungated_transfer: bool,


oh this is interesting... you can have a gated withdraw and a gated deposit....

davidiw · 2023-03-22T01:37:49Z

aptos-move/framework/aptos-framework/sources/fungible_asset/fungible_asset.move

+
+    #[resource_group_member(group = aptos_framework::object::ObjectGroup)]
+    /// The resource of an object recording the properties of the fungible assets held of the object owner.
+    struct AccountFungibleAsset has key {


gaah, no no, FungibleAssetResource or just FungibleResource

AccountFungibleAsset is the framework that let's a user specify their primary one.

davidiw · 2023-03-22T01:40:25Z

aptos-move/framework/aptos-framework/sources/fungible_asset/fungible_asset.move

+    }
+
+    /// Return the underlying fungible source.
+    public fun fungible_asset_source(fa: &FungibleAsset): Object<FungibleSource> {


let's not add fungible_asset to each of these, we should move against this double namespacing.

davidiw · 2023-03-22T01:42:53Z

aptos-move/framework/aptos-framework/sources/fungible_asset/fungible_caps.move

+    const ETRANSFER_CAP_AND_FUNGIBLE_ASSET_MISMATCH: u64 = 1;
+
+    /// Capability to mint fungible asset.
+    struct MintCap has store {


Let's use Ref per previous convos
We also use drop everywhere 😬

... you stressed the two things I hate.

lightmark · 2023-03-22T05:37:32Z

@davidiw fungible_caps has to use fungible_store to transfer fas. And fungible store depends on fungible_asset. There is no way to isolate fungible_store and merge the other three.

Basically if you have caps, you can burn from any account and transfer from/to any account so you must be aware of the fungible store.

davidiw · 2023-03-22T06:15:09Z

@davidiw fungible_caps has to use fungible_store to transfer fas. And fungible store depends on fungible_asset. There is no way to isolate fungible_store and merge the other three.

Basically if you have caps, you can burn from any account and transfer from/to any account so you must be aware of the fungible store.

Option 1) land as is
Option 2) I tweak and we land after I tweak

preference?

I'm going with Option 2... I have a new found appreciation for the hell you have been working on :)

lightmark · 2023-03-23T23:14:31Z

@davidiw the refactoring is done.

movekevin · 2023-03-24T02:16:00Z

aptos-move/framework/aptos-framework/sources/fungible_asset/fungible_store.move

+    }
+
+    /// Ensure the existence and return the `FungibleAssetWallet`.
+    inline fun ensure_fungible_asset_wallet(


This is outdated as it's creating FungibleAssetStore not fungible_asset_wallet

davidiw · 2023-03-24T05:36:17Z

aptos-move/framework/aptos-framework/sources/fungible_asset/fungible_store.move

+    /// Create a default `FungibleAssetWallet` object with zero balance of `metadata`.
+    fun create_account_fungible_asset_object(
+        account: address,
+        metadata: &Object<FungibleAssetMetadata>
+    ): Object<FungibleAssetWallet> {


I don't think we should restrict what is a fungible asset (wallet) and what isn't

I'd prefer we just allow someone to pass in a constructor ref and to their thing

this should be parallelizable -- otherwise account creation will become serial

davidiw · 2023-03-24T15:00:39Z

aptos-move/framework/aptos-framework/sources/fungible_asset/fungible_store.move

+    /// Remove the `FungibleAssetWallet` object of `metadata` from `account` if balance drops to 0 and
+    /// `allowed_ungated_transfer` is allowed.
+    inline fun maybe_delete(wallet: Object<FungibleAssetWallet>) acquires FungibleAssetStore {
+        if (fungible_asset::balance(&wallet) == 0 && fungible_asset::ungated_transfer_allowed(&wallet)) {


let's revisit the goal here, I don't think we just want to delete something if it is empty
consider the case where it is your primary wallet, I think that lifetime should be managed by the fungible_store

This is something I am not quite sure. I can remove it for now, but also keep in mind that you may not want the wallets with 0 balance of different metadata objects that you just used once.

aptos-move/framework/aptos-framework/sources/fungible_asset/managed_fungible_metadata.move

davidiw · 2023-03-24T15:14:14Z

aptos-move/framework/aptos-framework/sources/fungible_asset/managed_fungible_metadata.move

+
+    #[resource_group_member(group = aptos_framework::object::ObjectGroup)]
+    /// Hold refs to control the minting, transfer and burning of fungible assets.
+    struct ManagingRefs has key {


let's be bland here and call this ManagedAsset

I don't have an opinion here.

davidiw · 2023-03-24T15:14:52Z

aptos-move/framework/aptos-framework/sources/fungible_asset/managed_fungible_metadata.move

+        assert_owner(metadata_owner, metadata);
+        let mint_ref = borrow_mint_from_refs(metadata);
+        let fa = fungible_asset::mint(mint_ref, amount);
+        fungible_store::deposit(fa, to);


I don't think this module should know about fungible store

That's quite different than I thought. Then basically we have to build another layer otherwise most users will reinvent the wheel. Agree?

davidiw · 2023-03-24T15:15:38Z

aptos-move/move-examples/fungible_asset/sources/coin.move

@@ -0,0 +1,48 @@
+/// This is an example showing how to create a fungible asset and how to use it.
+module fungible_asset::coin {


does this exist purely for demos and testing? I think this can be incorporated as an integration test

showing ppl how to use it as a demo

davidiw · 2023-03-24T15:16:55Z

aptos-move/framework/aptos-framework/sources/fungible_asset/fungible_store.move

+    /// Return true if `account` allows ungated transfer.
+    public fun ungated_transfer_allowed<T: key>(
+        account: address,
+        metadata: &Object<T>
+    ): bool acquires FungibleAssetStore {
+        let metadata = fungible_asset::verify(metadata);
+        let afa_opt = get_account_fungible_asset_object(
+            account,
+            &metadata,
+            false
+        );
+        if (option::is_none(&afa_opt)) {
+            return true
+        };
+        let wallet = option::destroy_some(afa_opt);
+        fungible_asset::ungated_transfer_allowed(&wallet)
+    }
+
+    /// Enable/disable the direct transfer.
+    public fun set_ungated_transfer(
+        ref: &TransferRef,
+        account: address,
+        allow: bool
+    ) acquires FungibleAssetStore {
+        let metadata = fungible_asset::verify(&fungible_asset::transfer_ref_metadata(ref));
+        let afa_opt = get_account_fungible_asset_object(account, &metadata, !allow);
+        if (option::is_none(&afa_opt)) {
+            return
+        };
+        let wallet = option::destroy_some(afa_opt);
+        fungible_asset::set_ungated_transfer(ref, &wallet, allow);
+        maybe_delete(wallet);
+    }


I think for this store, we should just expose the most trivial operations, let's consider deleting these

If we delete this, users have to implement all those by themselves?

davidiw · 2023-03-24T15:28:00Z

There's a lot of work that needs to be done here before this is ready for 1.4 cut.

movekevin · 2023-03-24T15:30:24Z

aptos-move/framework/aptos-framework/sources/fungible_asset/fungible_asset.move

+    }
+
+    /// Destroy `wallet` object.
+    public(friend) fun destory_fungible_asset_wallet(


destory => destroy

…k/fungible_asset

gerben-stavenga · 2023-03-24T18:34:28Z

aptos-move/framework/aptos-framework/sources/fungible_asset.move

+    /// Define the metadata required of an metadata to be fungible.
+    struct FungibleAssetMetadata has key {
+        /// The current supply.
+        supply: u64,


I suggest we use u128

github-actions · 2023-03-24T19:03:55Z

✅ Forge suite `land_blocking` success on `9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e`

performance benchmark with full nodes : 5696 TPS, 6964 ms latency, 9900 ms p99 latency,no expired txns
Test Ok

github-actions · 2023-03-24T19:07:30Z

✅ Forge suite `compat` success on `testnet_2d8b1b57553d869190f61df1aaf7f31a8fc19a7b` ==> `9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e`

Compatibility test results for testnet_2d8b1b57553d869190f61df1aaf7f31a8fc19a7b ==> 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e (PR)
1. Check liveness of validators at old version: testnet_2d8b1b57553d869190f61df1aaf7f31a8fc19a7b
compatibility::simple-validator-upgrade::liveness-check : 7863 TPS, 4896 ms latency, 7200 ms p99 latency,no expired txns
2. Upgrading first Validator to new version: 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e
compatibility::simple-validator-upgrade::single-validator-upgrade : 5184 TPS, 7838 ms latency, 11000 ms p99 latency,no expired txns
3. Upgrading rest of first batch to new version: 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e
compatibility::simple-validator-upgrade::half-validator-upgrade : 4598 TPS, 8627 ms latency, 11200 ms p99 latency,no expired txns
4. upgrading second batch to new version: 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e
compatibility::simple-validator-upgrade::rest-validator-upgrade : 6466 TPS, 5983 ms latency, 10500 ms p99 latency,no expired txns
5. check swarm health
Compatibility test for testnet_2d8b1b57553d869190f61df1aaf7f31a8fc19a7b ==> 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e passed
Test Ok

github-actions · 2023-03-24T19:09:31Z

❌ Forge suite `framework_upgrade` failure on `cb4ba0a57c998c60cbab65af31a64875d2588ca5` ==> `9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e`

Compatibility test results for cb4ba0a57c998c60cbab65af31a64875d2588ca5 ==> 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e (PR)
Upgrade the nodes to version: 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e
Test Failed: API error: Unknown error Transaction committed on chain, but failed execution: Transaction Executed and Committed with Error CONSTRAINT_NOT_SATISFIED
Trailing Log Lines:
INCLUDING DEPENDENCY MoveStdlib
BUILDING ExecuteProposal
::error::API error: Unknown error Transaction committed on chain, but failed execution: Transaction Executed and Committed with Error CONSTRAINT_NOT_SATISFIED
test framework_upgrade::framework-upgrade ... FAILED
Error: API error: Unknown error Transaction committed on chain, but failed execution: Transaction Executed and Committed with Error CONSTRAINT_NOT_SATISFIED
Test Statistics: 
Compatibility test results for cb4ba0a57c998c60cbab65af31a64875d2588ca5 ==> 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e (PR)
Upgrade the nodes to version: 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e
Test Failed: API error: Unknown error Transaction committed on chain, but failed execution: Transaction Executed and Committed with Error CONSTRAINT_NOT_SATISFIED


Swarm logs can be found here: See fgi output for more information.
{"level":"INFO","source":{"package":"aptos_forge","file":"testsuite/forge/src/backend/k8s/cluster_helper.rs:281"},"thread_name":"main","hostname":"forge-framework-upgrade-pr-7183-1679683646-cb4ba0a57c998c60cbab","timestamp":"2023-03-24T19:09:24.482886Z","message":"Deleting namespace forge-framework-upgrade-pr-7183: Some(NamespaceStatus { phase: Some(\"Terminating\") })"}
{"level":"INFO","source":{"package":"aptos_forge","file":"testsuite/forge/src/backend/k8s/cluster_helper.rs:389"},"thread_name":"main","hostname":"forge-framework-upgrade-pr-7183-1679683646-cb4ba0a57c998c60cbab","timestamp":"2023-03-24T19:09:24.482911Z","message":"aptos-node resources for Forge removed in namespace: forge-framework-upgrade-pr-7183"}

failures:
    framework_upgrade::framework-upgrade

test result: FAILED. 0 passed; 1 failed; 0 filtered out

Failed to run tests:
Tests Failed
Error: Tests Failed
Debugging output:

lightmark commented Mar 15, 2023

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lightmark force-pushed the lightmark/fungible_asset branch from 2a1e180 to bcaefe1 Compare March 15, 2023 22:02

[fungible_asset] a layered design

4f55b75

lightmark force-pushed the lightmark/fungible_asset branch from bcaefe1 to 4f55b75 Compare March 15, 2023 22:04

[fungible_asset] add an example

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lightmark marked this pull request as ready for review March 15, 2023 23:33

lightmark requested review from davidiw, movekevin and wrwg as code owners March 15, 2023 23:33

davidiw reviewed Mar 16, 2023

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lightmark added 4 commits March 16, 2023 23:38

[fungible asset] improve code usability

63af328

fix nits

d038bf5

rename Caps to GoveranceCapabilities

9720468

fix inline

0466dfd

lightmark requested review from 0xchloe and CapCap March 17, 2023 22:16

lightmark added 3 commits March 17, 2023 16:41

add comments

27b920b

fix nits

c2e4dce

fix lints

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lightmark requested review from clay-aptos and saharct as code owners March 18, 2023 00:27

davidiw reviewed Mar 20, 2023

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[fa] move to framework and refactor

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lightmark added 3 commits March 21, 2023 15:37

fix comments and examples

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fix autogen docs

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fix tests

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lightmark added 4 commits March 23, 2023 15:52

refactor

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regen docs

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fix naming

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fix coin example

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rename supply

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davidiw approved these changes Mar 24, 2023

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movekevin enabled auto-merge (squash) March 24, 2023 18:05

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Merge branch 'main' of github.com:aptos-labs/aptos-core into lightmar…

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…k/fungible_asset

Fix lints

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movekevin merged commit 7c4a010 into main Mar 24, 2023

movekevin deleted the lightmark/fungible_asset branch March 24, 2023 19:07

lightmark mentioned this pull request Apr 11, 2023

[AIP-21][Discussion] Fungible Asset using objects aptos-foundation/AIPs#95

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thepomeranian mentioned this pull request Apr 18, 2023

[AIP-22][Discussion] No-Code Token Objects aptos-foundation/AIPs#101

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		#[test_only]
		use aptos_framework::fungible_source::init_test_fungible_source;

		@@ -0,0 +1,48 @@
		/// This is an example showing how to create a fungible asset and how to use it.
		module fungible_asset::coin {

[fungible_asset] a layered design #7183

[fungible_asset] a layered design #7183

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lightmark commented Mar 15, 2023

Description

Test Plan

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github-actions bot commented Mar 24, 2023

✅ Forge suite land_blocking success on 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e

github-actions bot commented Mar 24, 2023

✅ Forge suite compat success on testnet_2d8b1b57553d869190f61df1aaf7f31a8fc19a7b ==> 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e

github-actions bot commented Mar 24, 2023

❌ Forge suite framework_upgrade failure on cb4ba0a57c998c60cbab65af31a64875d2588ca5 ==> 9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e

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✅ Forge suite `land_blocking` success on `9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e`

✅ Forge suite `compat` success on `testnet_2d8b1b57553d869190f61df1aaf7f31a8fc19a7b` ==> `9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e`

❌ Forge suite `framework_upgrade` failure on `cb4ba0a57c998c60cbab65af31a64875d2588ca5` ==> `9a3f3fccc67f5f4576643690f1f7b7ce0b806e0e`