James Wilson
5db9b73899
* WIP Implementing new event subscription API * back to lifetimes, fix example * no more need for accept_weak_inclusion * thread lifetime through to prevent 'temporary dropped' issue * make working with events a little nicer * Get tests compiling * fmt and clippy * _name back to name * dont take ownership, just have stronger note * Attempt to fix test * remove commented-out code * Add a couple more helper methods and a test * Remove custom ExtrinsicFailed handling; treat them like other events * Handle runtime errors in TransactionProgress related bits * cargo fmt + clippy * Fix some of the failing tests * remove unused import * fix transfer_error test * Fix compile errors against new substrate latest * Comment tweaks, and force test-runtime rebuild * Drop the TransactionProgress subscription when we hit 'end' statuses * cargo fmt * find_event to find_first_event and helper to return all matching events * TransactionProgressStatus to TransactionStatus * Copy and improve docs on TransactionStatus from substrate * debug impl for Client to avoid manual debug impls elsewhere * Add and tweak comments, specifically a note about block inclusion on errors * clippy + fmt * Fix docs * Ignore 'error' statuses and adhere to the substrate docs * tweak and improve some comments per @dvdplm's suggestions * Break transaction* structs into separate file * fmt and fix doc link
subxt · 
A library to submit extrinsics to a substrate node via RPC.
⚠️ Health Warning ⚠️ considered alpha after recent changes, API still subject to change
See https://github.com/paritytech/subxt/issues/309 for an overview of outstanding issues.
Usage
Downloading metadata from a Substrate node
Use the subxt-cli tool to download the metadata for your target runtime from a node.
- Install:
cargo install subxt-cli
- Save the encoded metadata to a file:
subxt metadata -f bytes > metadata.scale
This defaults to querying the metadata of a locally running node on the default http://localhost:9933/. If querying
a different node then the metadata command accepts a --url argument.
Generating the runtime API from the downloaded metadata
Declare a module and decorate it with the subxt attribute which points at the downloaded metadata for the
target runtime:
#[subxt::subxt(runtime_metadata_path = "metadata.scale")]
pub mod node_runtime { }
Important: runtime_metadata_path resolves to a path relative to the directory where your crate's Cargo.toml
resides (CARGO_MANIFEST_DIR), not relative to the source file.
Initializing the API client
API is still a work in progress. See examples for the current usage.
Querying Storage
API is still a work in progress. See tests for the current usage.
Submitting Extrinsics
API is still a work in progress. See examples for the current usage.
Integration Testing
Most tests require a running substrate node to communicate with. This is done by spawning an instance of the
substrate node per test. It requires an executable binary substrate at polkadot-v0.9.10 on your path.
This can be installed from source via cargo:
cargo install --git https://github.com/paritytech/substrate node-cli --tag=polkadot-v0.9.10 --force
Alternatives
substrate-api-client provides similar functionality.