Disable default dependencies

Oct 13, 2025 by magicalceylontours.com 33 views

Introduction

When working with Rust libraries, it's not uncommon to encounter issues with dependencies. One such issue is the presence of a dependency on OpenSSL even after enabling the rustls feature. In this article, we'll delve into the problem, explore the dependency chain, and discuss possible solutions.

The Problem

Enabling the rustls feature on a crate is supposed to remove the dependency on OpenSSL. However, as reported by a user, the rustls feature still tries to pull in openssl and openssl-sys. This issue is not unique to a single crate, but rather a symptom of a more complex problem.

Dependency Chain

To understand the issue better, let's examine the dependency chain. According to the cargo tree command, the dependency chain looks like this:

musicbrainz_rs
reqwest
hyper-tls
native-tls
openssl
openssl-sys

As we can see, the dependency chain is quite long, and it's not immediately clear why reqwest is depending on both hyper-tls and hyper-rustls. However, upon closer inspection, we find that the native TLS feature is enabled by default in reqwest. This might be the reason why reqwest is depending on both hyper-tls and hyper-rustls.

Why Does This Happen?

So, why does enabling the rustls feature not remove the dependency on OpenSSL? There are a few possible reasons for this:

Default dependencies: As we saw earlier, reqwest has a default dependency on the native TLS feature, which in turn depends on openssl. This means that even if we enable the rustls feature, the dependency on openssl remains.
Transitive dependencies: When we enable the rustls feature, we might not be aware of the transitive dependencies that are being pulled in. In this case, the transitive dependency on openssl is being pulled in through the reqwest crate.
Crate configuration: The way crates are configured can also contribute to this issue. For example, if a crate is configured to use a specific version of openssl, even if we enable the rustls feature, the dependency on openssl might remain.

Solutions

So, what can we do to resolve this issue? Here are a few possible solutions:

Disable default dependencies: If we can disable the default dependencies in reqwest, we might be able to remove the dependency on openssl. This can be done by setting the native-tls feature to false in the reqwest crate.
Use a different TLS implementation: If we're not tied to using rustls, we can try using a different TLS implementation, such as native-tls. This might help us avoid the dependency on openssl.
Open a PR: If none of the above solutions work, we can try opening a PR to the reqwest crate to remove the dependency on openssl. This will require some effort, but it might be the best solution in the long run.

Conclusion

Introduction

In our previous article, we explored the issue of the rustls feature not removing the dependency on OpenSSL. We examined the dependency chain, discussed possible reasons for this issue, and proposed solutions. In this article, we'll answer some frequently asked questions (FAQs) related to this issue.

Q: Why does enabling the `rustls` feature not remove the dependency on OpenSSL?

A: There are several reasons why enabling the rustls feature might not remove the dependency on OpenSSL. These include default dependencies, transitive dependencies, and crate configuration.

Q: What are default dependencies?

A: Default dependencies are dependencies that are enabled by default in a crate. In the case of reqwest, the native TLS feature is enabled by default, which in turn depends on openssl.

Q: What are transitive dependencies?

A: Transitive dependencies are dependencies that are pulled in through another dependency. For example, if we enable the rustls feature, we might not be aware of the transitive dependency on openssl that is being pulled in through the reqwest crate.

Q: How can I disable default dependencies?

A: To disable default dependencies, you can set the native-tls feature to false in the reqwest crate. This will remove the dependency on openssl.

Q: What are some alternative TLS implementations?

A: Some alternative TLS implementations include native-tls and openssl. You can try using one of these implementations to see if it resolves the issue.

Q: How can I open a PR to remove the dependency on OpenSSL?

A: To open a PR to remove the dependency on OpenSSL, you'll need to create a pull request on the reqwest crate's GitHub repository. This will require some effort, but it might be the best solution in the long run.

Q: Why is this issue important?

A: This issue is important because it can cause problems with dependency management and crate configuration. By resolving this issue, we can ensure that crates are configured correctly and that dependencies are managed properly.

Q: How can I prevent this issue in the future?

A: To prevent this issue in the future, you can:

Be aware of default dependencies and transitive dependencies
Check the dependency chain before enabling features
Use alternative TLS implementations
Open PRs to resolve issues

Conclusion

In conclusion, the rustls feature not removing the dependency on OpenSSL is a complex issue that requires a deep understanding of the dependency chain. By answering some frequently asked questions, we can better understand this issue and find solutions to resolve it. Whether we disable default dependencies, use alternative TLS implementations, or open PRs, there are several ways to tackle this problem.