Describe each format in Rust and remove plugin.toml

crates/core/tests/group_read.rs

@@ -40,11 +40,7 @@ use sqlx::PgPool;
 /// NuGet, the built-in format plugin, as the `Format` the repository code
 /// works with.
 fn nuget() -> forge_plugin::PluginFormat {
-    let plugin = forge_plugin::Plugin::builtin(
-        forge_format_nuget::PLUGIN_TOML,
-        forge_format_nuget::Nuget::default(),
-    )
-    .expect("crates/formats/nuget/plugin.toml is valid");
+    let plugin = forge_plugin::Plugin::builtin(forge_format_nuget::Nuget::default());
     forge_plugin::PluginFormat::new(&plugin)
 }
 

crates/core/tests/hosted_read.rs

@@ -21,11 +21,7 @@ use sqlx::PgPool;
 /// NuGet, the built-in format plugin, as the `Format` the repository code
 /// works with.
 fn nuget() -> forge_plugin::PluginFormat {
-    let plugin = forge_plugin::Plugin::builtin(
-        forge_format_nuget::PLUGIN_TOML,
-        forge_format_nuget::Nuget::default(),
-    )
-    .expect("crates/formats/nuget/plugin.toml is valid");
+    let plugin = forge_plugin::Plugin::builtin(forge_format_nuget::Nuget::default());
     forge_plugin::PluginFormat::new(&plugin)
 }
 

crates/core/tests/hosted_write.rs

@@ -27,11 +27,7 @@ use tokio::sync::Mutex;
 /// NuGet, the built-in format plugin, as the `Format` the repository code
 /// works with.
 fn nuget() -> forge_plugin::PluginFormat {
-    let plugin = forge_plugin::Plugin::builtin(
-        forge_format_nuget::PLUGIN_TOML,
-        forge_format_nuget::Nuget::default(),
-    )
-    .expect("crates/formats/nuget/plugin.toml is valid");
+    let plugin = forge_plugin::Plugin::builtin(forge_format_nuget::Nuget::default());
     forge_plugin::PluginFormat::new(&plugin)
 }
 

crates/core/tests/proxy_read.rs

@@ -57,11 +57,7 @@ use tokio::sync::Notify;
 /// NuGet, the built-in format plugin, as the `Format` the repository code
 /// works with.
 fn nuget() -> forge_plugin::PluginFormat {
-    let plugin = forge_plugin::Plugin::builtin(
-        forge_format_nuget::PLUGIN_TOML,
-        forge_format_nuget::Nuget::default(),
-    )
-    .expect("crates/formats/nuget/plugin.toml is valid");
+    let plugin = forge_plugin::Plugin::builtin(forge_format_nuget::Nuget::default());
     forge_plugin::PluginFormat::new(&plugin)
 }
 

crates/core/tests/retention_worker.rs

@@ -36,11 +36,7 @@ use common::{pool, unique};
 /// NuGet, the built-in format plugin, as the `Format` the repository code
 /// works with.
 fn nuget() -> forge_plugin::PluginFormat {
-    let plugin = forge_plugin::Plugin::builtin(
-        forge_format_nuget::PLUGIN_TOML,
-        forge_format_nuget::Nuget::default(),
-    )
-    .expect("crates/formats/nuget/plugin.toml is valid");
+    let plugin = forge_plugin::Plugin::builtin(forge_format_nuget::Nuget::default());
     forge_plugin::PluginFormat::new(&plugin)
 }
 

crates/formats/README.md

@@ -12,15 +12,15 @@ the design, the contract and how to write one.
 
 A plugin directory holds:
 
-- `Cargo.toml`: a member of the workspace;
-- `plugin.toml`: the format id (also the directory's name), display name,
-  version, the `forge:format` contract version it targets (`api`), and
-  optionally its mount, repository kinds (`proxy` when it implements
-  `upstream`), its `storage` (`packages`, or `files` for a files format such
-  as raw) and `[assets]` names;
-- `src/`: `impl FormatPlugin`, and `pub const PLUGIN_TOML: &str =
-  forge_plugin_api::plugin_toml!();`.
+- `Cargo.toml`: a member of the workspace; its `version` is the plugin's;
+- `src/`: `impl FormatPlugin`, and the format's `pub const DESCRIPTOR:
+  Descriptor` that its `descriptor()` returns: the format id (also the
+  directory's name), display name, version (`env!("CARGO_PKG_VERSION")`),
+  description, mount, repository kinds (`Proxy` when it implements
+  `upstream`), its `storage` (`Packages`, or `Files` for a files format such
+  as raw) and its asset names.
 
 The server installs it in `plugins::builtin()`
-([`crates/server/src/plugins.rs`](../server/src/plugins.rs)). The
+([`crates/server/src/plugins.rs`](../server/src/plugins.rs)), whose tests
+check every built-in format's descriptor (`forge_plugin::descriptor`). The
 workspace builds, lints and tests the plugins like every other crate.

crates/formats/nuget/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "forge-format-nuget"
-# The plugin's own version: keep it equal to `version` in plugin.toml.
+# The plugin's own version, its descriptor's.
 version = "1.0.0"
 edition.workspace = true
 rust-version.workspace = true

crates/formats/nuget/src/lib.rs

@@ -1,6 +1,6 @@
 //! NuGet V3 feeds for Forge, as a format plugin.
 //!
-//! Served under `/v3/{repository}` (its `plugin.toml` names the mount):
+//! Served under `/v3/{repository}` (its [`DESCRIPTOR`] names the mount):
 //!
 //! * `GET /index.json` — the service index;
 //! * `GET /flat/{id}/index.json`, `/flat/{id}/{version}/{file}` — the flat
@@ -17,7 +17,7 @@
 //! Ids are matched case-insensitively (`ToLowerInvariant`); versions are
 //! NuGet versions, normalized (`1.0` → `1.0.0`).
 //!
-//! Forge links this plugin in ([`Nuget`], [`PLUGIN_TOML`]).
+//! Forge links this plugin in ([`Nuget`], [`DESCRIPTOR`]).
 
 pub mod model;
 pub mod nuspec;
@@ -28,14 +28,35 @@ pub mod version;
 use std::cmp::Ordering;
 
 use forge_plugin_api::{
-    Action, FetchResult, FormatError, FormatPlugin, Loaded, PackageSource, ParsedPackage, Remote,
-    Repository, Request, UpstreamOp, UpstreamStep,
+    Action, Assets, Descriptor, FetchResult, FormatError, FormatPlugin, Loaded, PackageSource,
+    ParsedPackage, Remote, Repository, RepositoryKind, Request, Storage, UpstreamOp, UpstreamStep,
 };
 
 pub use model::NupkgLimits;
 
-/// This plugin's `plugin.toml`: its format id, name, version and mount.
-pub const PLUGIN_TOML: &str = forge_plugin_api::plugin_toml!();
+/// What NuGet says about itself: its format id, name, version and mount.
+pub const DESCRIPTOR: Descriptor = Descriptor {
+    id: "nuget",
+    name: "NuGet",
+    version: env!("CARGO_PKG_VERSION"),
+    description: "NuGet V3 feeds: push, restore and search with dotnet, nuget.exe and Visual \
+                  Studio; proxies of nuget.org and other V3 feeds.",
+    mount: "/v3",
+    // Proxies mirror another V3 feed through the plugin's upstream side.
+    kinds: &[
+        RepositoryKind::Hosted,
+        RepositoryKind::Proxy,
+        RepositoryKind::Group,
+    ],
+    storage: Storage::Packages,
+    // The asset names and content types NuGet has always stored.
+    assets: Assets {
+        package: "package.nupkg",
+        package_type: "application/octet-stream",
+        manifest: "package.nuspec",
+        manifest_type: "application/xml",
+    },
+};
 
 /// The NuGet format, with the zip-bomb limits applied while parsing packages.
 #[derive(Debug, Clone, Default)]
@@ -51,6 +72,10 @@ impl Nuget {
 }
 
 impl FormatPlugin for Nuget {
+    fn descriptor(&self) -> &'static Descriptor {
+        &DESCRIPTOR
+    }
+
     fn canonical_id(&self, id: &str) -> String {
         nuspec::lower_id(id)
     }
@@ -100,21 +125,6 @@ impl FormatPlugin for Nuget {
 mod tests {
     use super::*;
 
-    #[test]
-    fn plugin_toml_names_this_crate() {
-        let value = |key: &str| {
-            PLUGIN_TOML
-                .lines()
-                .filter_map(|line| line.split_once('='))
-                .find(|(k, _)| k.trim() == key)
-                .map(|(_, v)| v.trim().trim_matches('"').to_string())
-        };
-        assert_eq!(value("id").as_deref(), Some("nuget"));
-        assert_eq!(value("version").as_deref(), Some(env!("CARGO_PKG_VERSION")));
-        assert_eq!(value("api").as_deref(), Some(forge_plugin_api::API));
-        assert_eq!(value("mount").as_deref(), Some("/v3"));
-    }
-
     #[test]
     fn the_rules_are_nugets() {
         let nuget = Nuget::default();

crates/formats/raw/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "forge-format-raw"
-# The plugin's own version: keep it equal to `version` in plugin.toml.
+# The plugin's own version, its descriptor's.
 version = "1.0.0"
 edition.workspace = true
 rust-version.workspace = true