The Rust programming language uses deterministic versioning for toolchain releases. Stable versions use SemVer, while nightly, beta and historical builds can be accessed by using dated builds (YY-MM-DD).
cargo-msrv is a tool which can be used to determine the minimal supported Rust version (MSRV). In cargo-msrv I started by parsing the latest channel manifest, and then decreasing the minor semver version. This is not great for many reasons: * Except for the latest released version, we are left guessing the decreased version numbers actually exist * Only stable versions are supported, not nightly, beta, or other channels * Only 1.x.0 versions are supported
As a result of the above limitations, I decided to look for an actual index of releases. After doing some research I found the following options:
1) Use the AWS index (e.g. aws --no-sign-request s3 ls static-rust-lang-org/dist/ > dist.txt)
* Rate-limited (only obtaining the index took ~40 seconds)
* source
2) Build from individual release manifests
* Requires parsing multiple documents
* Approx. one week delay after a new release
* Also has more specific toolchain information
* source
3) Parse Rust in-repo RELEASES.md
* Note: stable only
Each of these options requires additional parsing, which is where this crate comes in: this crate provides an index of all Rust releases. It will eventually support all three options, but initially, only the second one will be supported.