Subwasm

subwasm is an essential utility for Substrate developers and users. It allows inspecting any Substrate WASM runttime. A WASM Blob is by nature not very readable. Prior the development of subwasm, a running node was required to inspect a runtime.

subwasm voids this requirements. It is a Rust utility that allows inspecting a Substrate WASM runtime without having to run a node. It can be used to extract metadata, call some of the functions, and inspect the storage of a Substrate runtime and would not even require an internet connection (assuming you already have a runtime locally).

subwasm is used within srtool to extract metadata from a runtime that was just built.

subwasm allows knowing exaxctly the content of a runtime without the need to run a node. It is a great tool for users and for automation.

You may install subwasm using homebrew or cargo or build it yourself:

You may then use it to inspect a runtime. subwasm can also fetch a runtime from a chain. Wondering what is the current runtime version ?

will fetch the metadata of the Polkadot runtime, then show you the runtime version:

You can find the project at: https://github.com/chevdor/subwasm and see how to list pallets, query the details of a specific pallet, retrieve the entire metadata in various formats and much more.