Crate guppy

Track and query Cargo dependency graphs.

guppy provides a Rust interface to run queries over Cargo dependency graphs. guppy parses the output of cargo metadata, then presents a graph interface over it.

Optional features

• proptest010: Support for property-based testing using the proptest framework.
• rayon1: Support for parallel iterators through Rayon (preliminary work so far, more parallel iterators to be added in the future).
• summaries: Support for writing out build summaries.

Examples

Print out all direct dependencies of a package:

use guppy::{CargoMetadata, PackageId};

// `guppy` accepts `cargo metadata` JSON output. Use a pre-existing fixture for these examples.
let metadata = CargoMetadata::parse_json(include_str!("../../fixtures/small/metadata1.json")).unwrap();
let package_graph = metadata.build_graph().unwrap();

// `guppy` provides several ways to get hold of package IDs. Use a pre-defined one for this
// example.
let package_id = PackageId::new("testcrate 0.1.0 (path+file:///fakepath/testcrate)");

// The `metadata` method returns information about the package, or `None` if the package ID
// wasn't recognized.
let package = package_graph.metadata(&package_id).unwrap();

// `direct_links` returns all direct dependencies of a package.
for link in package.direct_links() {
    // A dependency link contains `from()`, `to()` and information about the specifics of the
    // dependency.
    println!("direct dependency: {}", link.to().id());
}

For more examples, see the examples directory.

Re-exports

pub use errors::Error;

pub use semver::Version;

pub use serde_json::Value as JsonValue;

Modules

errors	Contains types that describe errors and warnings that guppy methods can return.
graph	Entry point for analyzing Cargo dependency graphs.

Structs

CargoMetadata	A deserialized Cargo metadata returned by a MetadataCommand.
MetadataCommand	A builder for configuring cargo metadata invocations.
PackageId	An "opaque" identifier for a package.
Platform	A platform to evaluate target specs against.

Enums

DependencyKind	A descriptor for the kind of dependency.
TargetFeatures	A set of target features to match.
TargetSpecError	An error that happened during target-spec parsing or evaluation.

Traits

Obs	Trait representing an owned, borrowed or shared instance of T.