SDK for writing and testing canisters for the Internet Computer in Rust. This repo includes a few crates that help to simplify the tricky aspects of IC canisters development:
This project builds on top of ic-cdk
and ic-kit
crates. It is not intended to replace them, but adds some types and
macros to simplify things that are not dealt with by those crates.
The following crates are included in this repo:
ic-auction
- This crate provides an API trait for auction canisters. This crate is optional.ic-canister
- This crate provides a set of macros and types to simplify the development of canisters.ic-export
- This crate mainly re-exports commonly used dependencies fromic
dependencies.ic-log
- This crate provides a simple logger implementation of thelog
crate. Log records are saved into memory and can be inspected with a canister query.ic-metrics
- This crate provides an API trait to simplify the collection of metrics from canisters.ic-storage
- This crate provides a simple in-memory storage for canisters.
A wrapper crate among all the canisters in this repository with all the necessary re-exports. It some features for exporting factory and auction traits as well as their APIs.
Note: Currently we require each canister to have its own export-api
feature that will export the wasm definitions of
the canister (and hide them if this canister is used as a dependency). This is not the case with trait canisters as rust
features are additive even in transitive dependencies we're forced to introduce different export-api
features for
different traits in this repo (auction-api
and factory-api
respectively). The best approach will be to
use canister-sdk
dependency with dependent features that will trigger the necessary APIs transitively, e.g.
[ package ]
edition = "2021"
name = "awesome-canister"
version = "0.1.0"
[ features ]
default = []
export-api = ["canister-sdk/auction-api"]
auction = ["canister-sdk/auction"]
[ dependencies ]
canister-sdk = { git = "https://github.com/infinity-swap/canister-sdk", package = "canister-sdk" }
There's an example crate on how to use the export-api
feature in the canister-e directory. This crate shows how to use the export-api
features to export the methods in the canister and how to generate the idl for the canister with the methods included.
The ic-exports
crate re-exports commonly used ic
dependencies. This means that you can use the ic-exports
crate to
import the ic
dependencies without having to specify the version of the ic
dependencies in your Cargo.toml
file.
use ic_exports::*;
The common ic
dependencies that are re-exported are:
ic-cdk
ic-cdk-macros
ic-kit
ic-agent
ic-icrc1
ic-icrc1-index
ledger-canister
ic-ledger-core
ic-stable-structures
cycles-minting-canister
ic-base-types
ic-ic00-types
This crate introduces a framework to write easily testable canisters, including testing inter-canister calls, as well as a way to compose canister APIs using rust traits. There are few examples below, but for the details you can check out the crate documentation.
For example, you can have a canister with simple API:
#[derive(Clone, Canister)]
struct MyCanister {
#[id]
principal: Principal,
#[state]
state: Rc<RefCell<MyCanisterState>>,
}
impl MyCanister {
#[query]
fn get_counter(&self) -> u64 {
self.state.borrow().counter
}
#[update]
fn add(&self, value: u64) {
self.state.borrow_mut().counter += value;
}
}
Now instead of using ic_cdk::api::call
to query these APIs from another canister doing manual
serialization/deserialization:
impl MyOtherCanister {
#[update]
async fn increment_get(&self, id: Principal) -> u64 {
let my_canister = MyCanister::from_principal(id);
canister_call!(my_canister.add(1), ()).await.unwrap();
let updated_value = canister_call!(my_canister.get_counter(), u64).await.unwrap();
updated_value
}
}
Now, if you want to test the increment_get
method of you canister, all you need to do is to write a unit test:
#[tokio::test]
async fn test_increment_get() {
let my_canister = MyCanister::init_instance();
let my_other_canister = MyOtherCanister::init_instance();
assert_eq!(my_other_canister.increment_get(my_canister.principal()), 1);
assert_eq!(my_other_canister.increment_get(my_canister.principal()), 2);
}
Even though the canisters use statics internally to store the canister state, the tests can initialize multiple
instances of
canisters with init_instance
method, and each one of them will have a separate state.
It is also possible to write a trait to store some part of the canister API that can be reused in different canisters. This also allows to compose a canister from different traits just by implementing the needed traits for your canister Struct:
impl Factory for MyCanister {
fn state(&self) -> Rc<RefCell<FactoryState>> {
<Self as Factory>::FactoryStateState::get()
}
}
impl OtherCanisterTrait for MyCanister {
// impl
}
For other examples you can look into the tests
If you use ic-cdk
to create your canister's API's, you cannot simply use a canister as a rust dependency for another
canister, because all the APIs of that dependency will not be included into the canister you're implementing. If you
create a canister using canister-sdk
, don't forget to add a export-api
feature to the dependency so that it will
export all the wasm from the canister trait definition (more specifically from one that is auto-generated
by generate_exports!
macro).
Some helpers and wrappers over principals we use on day-to-day basis for ledger and management canister calls.
Introduces traits IcStorage
and Versioned
for in-memory and stable storage management respectively.
In the past, the ic-cdk
crate provided methods in the ic_cdk::storage
module to store and get structs from the
canister's memory, but they were removed in version 0.5.0
(for a good reason). The recommended way to store the data
in the canister
memory is to use thread_local
storage with RefCell
controlling access to the struct.
The ic_storage::IcStorage
deriving macro does exactly that, but saving you some boilerplate. Using it is quite
straightforward:
use ic_storage::IcStorage;
#[derive(IcStorage, Default)]
struct MyCanisterState {
value: u32,
}
let local_state = MyCanisterState::get();
assert_eq!(local_state.borrow().value, 0);
local_state.borrow_mut().value = 42;
assert_eq!(local_state.borrow().value, 42);
It also allows having generic state structures. For detailed information, check out the crate level documentation.
The ic_storage::stable
module introduces Versioned
trait that allows transparent upgrades for the state during
canister upgrades (even over several versions of state at once). When using this trait, the state structure can
be serialized into the stable storage using ic_storage::stable::write
method. Then after the upgrade, simply use
ic_storage::stable::read::<NewStateType>()
. This will read the serialized previous version of the state, check its
version and run the upgrade methods until the current version of the type (the NewStateType
struct) is reached.
Check out the module level documentation for more details.
When using Canister
deriving macro, the fields that are marked with #[state]
attribute are all preserved over
canister upgrades. This is done using Versioned
trait. This means that at this moment you can have only one #[state]
in a canister. If the state type is changed, the new state must have the previous state type as
its Versioned::Previous
type. The Canister
deriving macro takes care of generating the pre_upgrade
and post_upgrade
functions and updating the state to the new type when needed.
If a canister needs to have a state that is not preserved during the upgrade process (like caches or some other
temporary data), #[state(stable_store = false)]
can be used in addition to the #[state]
field. Any number of
non-stable state fields can be added to a canister.
Metrics trait that the canister can implement to store a history of necessary metrics (stored
in MetricsData)
for the canister that also
allows to overwrite the update_metrics
call to store custom metrics for a canister. For an example you can refer to
the tests.
This crate currently provides two APIs for metrics, these are :-
get_metrics
- This API returns the metrics data for the canister. It returns snapshot of the metrics data over a certain period of the interval.get_curr_metrics
- This API returns the current metrics data for the canister.
The IC canisters needs cycles to run and as well as to pay for the storage. This crate provides a mechanism of cycle
auctions, that doesn't require owner's attention for the canister cycle management. Cycle auctions are run in a set of
intervals, and allow any user to add cycles to the canister and retrieve a reward set up via disburse_rewards
call as
a reward for doing so. You can find more information about the cycle auctions in the README.
This crate is optional and can be used by adding the feature auction
to your Cargo.toml
file.
[ dependencies ]
canister-sdk = { git = "https://github.com/infinity-swap/canister-sdk", features = ["auction"] tag = "vx.x.xx"}
Note: When you're using the canister-sdk
with these crates, make sure to include export-api
feature as well, and
when building the canister, make sure to include the --export-api
flag.
IC log is a log library for IC canisters. It allows you to use the log
crate macros (debug!
, info!
, error!
...) into a canister. The records are written into memory with a configurable history size and can be later be retrieved by a query to the canister.
You can see ic-log in action in the examples