Skip to main content
Back

Developer weekly update September 20, 2023

September 20 2023

Hello everyone and welcome back to this week's issue of the Internet Computer developer weekly! In this issue, we'll dive into the new releases of dfx v0.15.0 and the Rust CDK v0.11.0. Both of these releases have some incredible new features for developers, so let's dive into it!

dfx v0.15.0​

dfx v0.15.0 has been shipped with several new features and adjustments to enhance the developer experience and enable new workflows. Some of these new features include:

  • dfx nns and dfx sns have been removed as commands and turned into subcommands of the dfx extension, such as dfx extension install nns and dfx extension install sns.

  • The dfx replica and dfx bootstrap commands have been removed. dfx start should be used instead.

  • Warnings about using an unencrypted identity can be now be suppressed.

  • https://icp-api.io has been added to the default Content-Security-Policy header. Existing projects will need to update this value in their .ic-assets.json or .ic-assets.json5 file, then redeploy their project.

  • The default value of allow_raw_access has been changed to true, meaning that raw assets are now available by default. The frontend canister will not restrict access of traffic to the <canister-id>.raw.icp0.io URL, nor will it redirect requests to the certified domain <canister-id>.icp0.io unless configured.

  • New identities are restricted to using the characters ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz.-_@0123456789.

  • dfx now waits for the new module hash when installing a wallet to eliminate wallet installation errors.

  • Response verification v2 has been re-enabled in the asset canister.

You can read the full release notes with additional details here.

IC Rust CDK v0.11.0​

In the latest version of the Rust CDK, the Candid export workflow has changed. In this update, there is no need to compile for WASI separately. Instead, canisters should still use the ic_cdk::export_candid!() function to export the canister's Candid file, then the candid_extractor can be used to extract the Candid from the canister's Wasm. The candid_extractor is a CLI tool that can be used to extract the Candid definition from the canister's Wasm.

Preparation​

  • Step 1: Upgrade ic-cdk dependency to v0.11.0 or higher:​

# Cargo.toml
[dependencies]
ic-cdk = "0.11.0"
cargo install candid-extractor

With cargo-binstall you can install the prebuilt binary without waiting for compilation:

cargo binstall candid-extractor

Workflow​

  • Step 1: Call the export_candid macro at the end of your lib.rs file:​

#[query]
fn hello(name: String) -> String {
    format!("Hello, {}!", name)
}

#[update]
fn world(name: String) -> String {
    format!("World, {}!", name)
}

// Enable Candid export
ic_cdk::export_candid!();

  • Step 2: Compile the Canister Wasm module​

cargo build --release --target wasm32-unknown-unknown --package <CANISTER>

The Wasm module will be at:

target/wasm32-unknown-unknown/release/<CANISTER>.wasm

  • Step 3: Extract candid from the Wasm module and save to a file:​

candid-extractor target/wasm32-unknown-unknown/release/<CANISTER>.wasm > <CANISTER>.did

That'll wrap things up for this week! See everyone in the next issue of developer weekly!

-DFINITY