Add uv workspace metadata

crates/uv-cli/src/lib.rs

@@ -517,6 +517,13 @@ pub enum Commands {
     Build(BuildArgs),
     /// Upload distributions to an index.
     Publish(PublishArgs),
+    /// Manage workspaces.
+    #[command(
+        after_help = "Use `uv help workspace` for more details.",
+        after_long_help = "",
+        hide = true
+    )]
+    Workspace(WorkspaceNamespace),
     /// The implementation of the build backend.
     ///
     /// These commands are not directly exposed to the user, instead users invoke their build
@@ -6835,6 +6842,22 @@ pub struct PublishArgs {
     pub dry_run: bool,
 }
 
+#[derive(Args)]
+pub struct WorkspaceNamespace {
+    #[command(subcommand)]
+    pub command: WorkspaceCommand,
+}
+
+#[derive(Subcommand)]
+pub enum WorkspaceCommand {
+    /// Display package metadata.
+    #[command(hide = true)]
+    Metadata(MetadataArgs),
+}
+
+#[derive(Args, Debug)]
+pub struct MetadataArgs;
+
 /// See [PEP 517](https://peps.python.org/pep-0517/) and
 /// [PEP 660](https://peps.python.org/pep-0660/) for specifications of the parameters.
 #[derive(Subcommand)]

crates/uv-preview/src/lib.rs

@@ -22,6 +22,7 @@ bitflags::bitflags! {
         const S3_ENDPOINT = 1 << 10;
         const CACHE_SIZE = 1 << 11;
         const INIT_PROJECT_FLAG = 1 << 12;
+        const WORKSPACE_METADATA = 1 << 13;
     }
 }
 
@@ -44,6 +45,7 @@ impl PreviewFeatures {
             Self::S3_ENDPOINT => "s3-endpoint",
             Self::CACHE_SIZE => "cache-size",
             Self::INIT_PROJECT_FLAG => "init-project-flag",
+            Self::WORKSPACE_METADATA => "workspace-metadata",
             _ => panic!("`flag_as_str` can only be used for exactly one feature flag"),
         }
     }
@@ -94,12 +96,12 @@ impl FromStr for PreviewFeatures {
                 "s3-endpoint" => Self::S3_ENDPOINT,
                 "cache-size" => Self::CACHE_SIZE,
                 "init-project-flag" => Self::INIT_PROJECT_FLAG,
+                "workspace-metadata" => Self::WORKSPACE_METADATA,
                 _ => {
                     warn_user_once!("Unknown preview feature: `{part}`");
                     continue;
                 }
             };
-
             flags |= flag;
         }
 

crates/uv/src/commands/mod.rs

@@ -67,6 +67,7 @@ use uv_normalize::PackageName;
 use uv_python::PythonEnvironment;
 use uv_scripts::Pep723Script;
 pub(crate) use venv::venv;
+pub(crate) use workspace::metadata::metadata;
 
 use crate::printer::Printer;
 
@@ -88,6 +89,7 @@ pub(crate) mod reporters;
 mod self_update;
 mod tool;
 mod venv;
+mod workspace;
 
 #[derive(Copy, Clone)]
 pub(crate) enum ExitStatus {

crates/uv/src/commands/workspace/metadata.rs

@@ -0,0 +1,91 @@
+use std::fmt::Write;
+use std::path::Path;
+
+use anyhow::Result;
+use serde::Serialize;
+
+use uv_fs::PortablePathBuf;
+use uv_normalize::PackageName;
+use uv_preview::{Preview, PreviewFeatures};
+use uv_warnings::warn_user;
+use uv_workspace::{DiscoveryOptions, Workspace, WorkspaceCache};
+
+use crate::commands::ExitStatus;
+use crate::printer::Printer;
+
+/// The schema version for the metadata report.
+#[derive(Serialize, Debug, Default)]
+#[serde(rename_all = "snake_case")]
+enum SchemaVersion {
+    /// An unstable, experimental schema.
+    #[default]
+    Preview,
+}
+
+/// The schema metadata for the metadata report.
+#[derive(Serialize, Debug, Default)]
+struct SchemaReport {
+    /// The version of the schema.
+    version: SchemaVersion,
+}
+
+/// Report for a single workspace member.
+#[derive(Serialize, Debug)]
+struct WorkspaceMemberReport {
+    /// The name of the workspace member.
+    name: PackageName,
+    /// The path to the workspace member's root directory.
+    path: PortablePathBuf,
+}
+
+/// The report for a metadata operation.
+#[derive(Serialize, Debug)]
+struct MetadataReport {
+    /// The schema of this report.
+    schema: SchemaReport,
+    /// The workspace root directory.
+    workspace_root: PortablePathBuf,
+    /// The workspace members.
+    members: Vec<WorkspaceMemberReport>,
+}
+
+/// Display metadata about the workspace.
+pub(crate) async fn metadata(
+    project_dir: &Path,
+    preview: Preview,
+    printer: Printer,
+) -> Result<ExitStatus> {
+    if preview.is_enabled(PreviewFeatures::WORKSPACE_METADATA) {
+        warn_user!(
+            "The `uv workspace metadata` command is experimental and may change without warning. Pass `--preview-features {}` to disable this warning.",
+            PreviewFeatures::WORKSPACE_METADATA
+        );
+    }
+
+    let workspace_cache = WorkspaceCache::default();
+    let workspace =
+        Workspace::discover(project_dir, &DiscoveryOptions::default(), &workspace_cache).await?;
+
+    let members = workspace
+        .packages()
+        .values()
+        .map(|package| WorkspaceMemberReport {
+            name: package.project().name.clone(),
+            path: PortablePathBuf::from(package.root().as_path()),
+        })
+        .collect();
+
+    let report = MetadataReport {
+        schema: SchemaReport::default(),
+        workspace_root: PortablePathBuf::from(workspace.install_path().as_path()),
+        members,
+    };
+
+    writeln!(
+        printer.stdout(),
+        "{}",
+        serde_json::to_string_pretty(&report)?
+    )?;
+
+    Ok(ExitStatus::Success)
+}

crates/uv/src/commands/workspace/mod.rs

@@ -0,0 +1 @@
+pub(crate) mod metadata;

crates/uv/src/lib.rs

@@ -26,7 +26,8 @@ use uv_cli::SelfUpdateArgs;
 use uv_cli::{
     AuthCommand, AuthNamespace, BuildBackendCommand, CacheCommand, CacheNamespace, Cli, Commands,
     PipCommand, PipNamespace, ProjectCommand, PythonCommand, PythonNamespace, SelfCommand,
-    SelfNamespace, ToolCommand, ToolNamespace, TopLevelArgs, compat::CompatArgs,
+    SelfNamespace, ToolCommand, ToolNamespace, TopLevelArgs, WorkspaceCommand, WorkspaceNamespace,
+    compat::CompatArgs,
 };
 use uv_client::BaseClientBuilder;
 use uv_configuration::min_stack_size;
@@ -1733,6 +1734,11 @@ async fn run(mut cli: Cli) -> Result<ExitStatus> {
             )
             .await
         }
+        Commands::Workspace(WorkspaceNamespace { command }) => match command {
+            WorkspaceCommand::Metadata(_args) => {
+                commands::metadata(&project_dir, globals.preview, printer).await
+            }
+        },
         Commands::BuildBackend { command } => spawn_blocking(move || match command {
             BuildBackendCommand::BuildSdist { sdist_directory } => {
                 commands::build_backend::build_sdist(&sdist_directory)

crates/uv/tests/it/common/mod.rs

@@ -1064,6 +1064,14 @@ impl TestContext {
         command
     }
 
+    /// Create a `uv workspace metadata` command with options shared across scenarios.
+    pub fn workspace_metadata(&self) -> Command {
+        let mut command = Self::new_command();
+        command.arg("workspace").arg("metadata");
+        self.add_shared_options(&mut command, false);
+        command
+    }
+
     /// Create a `uv export` command with options shared across scenarios.
     pub fn export(&self) -> Command {
         let mut command = Self::new_command();

crates/uv/tests/it/main.rs

@@ -141,3 +141,4 @@ mod workflow;
 
 mod extract;
 mod workspace;
+mod workspace_metadata;

crates/uv/tests/it/show_settings.rs

@@ -7831,7 +7831,7 @@ fn preview_features() {
         show_settings: true,
         preview: Preview {
             flags: PreviewFeatures(
-                PYTHON_INSTALL_DEFAULT | PYTHON_UPGRADE | JSON_OUTPUT | PYLOCK | ADD_BOUNDS | PACKAGE_CONFLICTS | EXTRA_BUILD_DEPENDENCIES | DETECT_MODULE_CONFLICTS | FORMAT | NATIVE_AUTH | S3_ENDPOINT | CACHE_SIZE | INIT_PROJECT_FLAG,
+                PYTHON_INSTALL_DEFAULT | PYTHON_UPGRADE | JSON_OUTPUT | PYLOCK | ADD_BOUNDS | PACKAGE_CONFLICTS | EXTRA_BUILD_DEPENDENCIES | DETECT_MODULE_CONFLICTS | FORMAT | NATIVE_AUTH | S3_ENDPOINT | CACHE_SIZE | INIT_PROJECT_FLAG | WORKSPACE_METADATA,
             ),
         },
         python_preference: Managed,
@@ -8059,7 +8059,7 @@ fn preview_features() {
         show_settings: true,
         preview: Preview {
             flags: PreviewFeatures(
-                PYTHON_INSTALL_DEFAULT | PYTHON_UPGRADE | JSON_OUTPUT | PYLOCK | ADD_BOUNDS | PACKAGE_CONFLICTS | EXTRA_BUILD_DEPENDENCIES | DETECT_MODULE_CONFLICTS | FORMAT | NATIVE_AUTH | S3_ENDPOINT | CACHE_SIZE | INIT_PROJECT_FLAG,
+                PYTHON_INSTALL_DEFAULT | PYTHON_UPGRADE | JSON_OUTPUT | PYLOCK | ADD_BOUNDS | PACKAGE_CONFLICTS | EXTRA_BUILD_DEPENDENCIES | DETECT_MODULE_CONFLICTS | FORMAT | NATIVE_AUTH | S3_ENDPOINT | CACHE_SIZE | INIT_PROJECT_FLAG | WORKSPACE_METADATA,
             ),
         },
         python_preference: Managed,