Simplify dependencies to Linera binaries

[ma2bd]

Motivation

We have three ways to obtain Linera binaries at the moment: release mode (look up in CARGO_HOME), debug mode (cargo build), test-runner (look up in CARGO_HOME + cargo install if needed).

This is rather complicated and create some subtle limitations:

• We cannot run tests in release mode (it will fetch the binaries with cargo install)
• We cannot rename the test runner because cargo install from the network would break CI.

Proposal

In the long term, cargo should eventually provide a way to depend on the binaries of another crate (rust-lang/cargo#9096). In the meantime, we only have partial solutions. At least we're going for a simple one here (removing lots of code such as the feature detection).

1. Use a single resolve_binary function what all the cases.

• In production, it will just look at a directory where the current binary is.
• In the case of integration tests run from target/{debug,release}/deps, it will look at the directory above.
• We suggest how to provide the missing binaries (with cargo build or cargo install) but do not do it ourselves any more.

There will be two cargo install documented for users (test runner and linera-service).

For tests, cargo test always build the binaries of the current crate(s). So, the only potential remaining issue is when a test depends on the binary of another crate. This is rare as most e2e tests are inside linera-service. In CI, we run cargo build anyway first.

2. Add a version check based on the crate version (Linera callers and callees must have the same version).

• CAVEAT: All Linera binaries must use StructOpt (or at least recognize --version in the same way)
• Make sure to support --version in schema_export

3. Details:

• The first commit in the PR also fixes CI for linera-service-graphql-client.
• This PR caught a few places where we still used version 0.4.0 instead of 0.4.1.

Test Plan

CI

Release Plan

• Need to bump the major version number in the next release of the crates.
• Need to update the developer manual. ==> need to cargo install linera-sdk explicitly

Links

stacked on top of #1106

[afck]

🤩 🚀

[afck]

😞

[ma2bd]

lol

[christos-h]

This is a little harder to read, consider: https://doc.rust-lang.org/std/path/struct.Path.html#method.ends_with

 if path.ends_with(Path::new("target/debug/deps")) || path.ends_with(Path::new("target/release/deps")) {

[ma2bd]

nice

[ma2bd]

Actually Path::new is not even needed

[christos-h]

You can just use with_context here (since formatting is expensive and you want to do it lazily). You don't need the map_err as the error will be shown anyway:

Error: Failed to execute and retrieve version from the binary {name} in directory {}

Caused by:
    {e}

[ma2bd]

with_context seems to only work if you have an anyhow::Result already.

[afck]

The documentation says the error type just has to be StdError + Send + Sync + 'static.

[christos-h]

Same here I think?

[christos-h]

Nothing blocking, just a few suggestions. LGTM :)