WIT-based environment syntax

Signed-off-by: itowlson <[email protected]>

Author: itowlson

Cargo.lock

@@ -7,7 +7,10 @@ edition = { workspace = true }
 [dependencies]
 anyhow = { workspace = true }
 async-trait = "0.1"
+bytes = "1.1"
 futures = "0.3"
+futures-util = "0.3"
+id-arena = "2"
 indexmap = "2.2.6"
 miette = "7.2.0"
 oci-distribution = { git = "https://github.com/fermyon/oci-distribution", rev = "7e4ce9be9bcd22e78a28f06204931f10c44402ba" }
@@ -26,6 +29,8 @@ wac-parser = "0.6.0"
 wac-resolver = "0.6.0"
 wac-types = "0.6.0"
 wasm-pkg-loader = "0.4.1"
+wit-component = "0.217.0"
+wit-parser = "0.217.0"
 
 [lints]
 workspace = true

crates/environments/Cargo.toml

@@ -1,37 +1,112 @@
-use wasm_pkg_loader::PackageRef;
+use anyhow::Context;
 
-#[derive(Debug, serde::Deserialize)]
-pub struct TargetEnvironment {
-    pub name: String,
-    pub environments: std::collections::HashMap<TriggerType, TargetWorld>,
-}
+pub async fn load_environment(env_id: &str) -> anyhow::Result<TargetEnvironment> {
+    use futures_util::TryStreamExt;
+
+    let (pkg_name, pkg_ver) = env_id.split_once('@').unwrap();
+
+    let mut client = wasm_pkg_loader::Client::with_global_defaults()?;
+
+    let package = pkg_name.to_owned().try_into().context("pkg ref parse")?;
+    let version = wasm_pkg_loader::Version::parse(pkg_ver).context("pkg ver parse")?;
+
+    let release = client
+        .get_release(&package, &version)
+        .await
+        .context("get release")?;
+    let stm = client
+        .stream_content(&package, &release)
+        .await
+        .context("stream content")?;
+    let bytes = stm
+        .try_collect::<bytes::BytesMut>()
+        .await
+        .context("collect stm")?
+        .to_vec();
 
-#[derive(Debug, Eq, Hash, PartialEq, serde::Deserialize)]
-pub struct TargetWorld {
-    wit_package: PackageRef,
-    package_ver: String, // TODO: tidy to semver::Version
-    world_name: WorldNames,
+    TargetEnvironment::new(env_id.to_owned(), bytes)
 }
 
-#[derive(Debug, Eq, Hash, PartialEq, serde::Deserialize)]
-#[serde(untagged)]
-enum WorldNames {
-    Exactly(String),
-    AnyOf(Vec<String>),
+pub struct TargetEnvironment {
+    name: String,
+    decoded: wit_parser::decoding::DecodedWasm,
+    package: wit_parser::Package, // saves unwrapping it every time
+    package_id: id_arena::Id<wit_parser::Package>,
+    package_bytes: Vec<u8>,
 }
 
-impl TargetWorld {
-    fn versioned_name(&self, world_name: &str) -> String {
-        format!("{}/{}@{}", self.wit_package, world_name, self.package_ver)
+impl TargetEnvironment {
+    fn new(name: String, bytes: Vec<u8>) -> anyhow::Result<Self> {
+        let decoded = wit_component::decode(&bytes).context("decode wasm")?;
+        let package_id = decoded.package();
+        let package = decoded
+            .resolve()
+            .packages
+            .get(package_id)
+            .context("should had a package")?
+            .clone();
+
+        Ok(Self {
+            name,
+            decoded,
+            package,
+            package_id,
+            package_bytes: bytes,
+        })
+    }
+
+    pub fn is_world_for(&self, trigger_type: &TriggerType, world: &wit_parser::World) -> bool {
+        world.name.starts_with(&format!("trigger-{trigger_type}"))
+            && world.package.is_some_and(|p| p == self.package_id)
+    }
+
+    pub fn supports_trigger_type(&self, trigger_type: &TriggerType) -> bool {
+        self.decoded
+            .resolve()
+            .worlds
+            .iter()
+            .any(|(_, world)| self.is_world_for(trigger_type, world))
+    }
+
+    pub fn worlds(&self, trigger_type: &TriggerType) -> Vec<String> {
+        self.decoded
+            .resolve()
+            .worlds
+            .iter()
+            .filter(|(_, world)| self.is_world_for(trigger_type, world))
+            .map(|(_, world)| self.world_qname(world))
+            .collect()
+    }
+
+    /// Fully qualified world name (e.g. fermyon:spin/[email protected])
+    fn world_qname(&self, world: &wit_parser::World) -> String {
+        let version_suffix = match self.package_version() {
+            Some(version) => format!("@{version}"),
+            None => "".to_owned(),
+        };
+        format!(
+            "{}/{}{version_suffix}",
+            self.package_namespaced_name(),
+            world.name,
+        )
+    }
+
+    /// The environment name for UI purposes
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    /// Namespaced but unversioned package name (e.g. spin:cli)
+    pub fn package_namespaced_name(&self) -> String {
+        format!("{}:{}", self.package.name.namespace, self.package.name.name)
+    }
+
+    pub fn package_version(&self) -> Option<&semver::Version> {
+        self.package.name.version.as_ref()
     }
 
-    pub fn versioned_names(&self) -> Vec<String> {
-        match &self.world_name {
-            WorldNames::Exactly(name) => vec![self.versioned_name(name)],
-            WorldNames::AnyOf(names) => {
-                names.iter().map(|name| self.versioned_name(name)).collect()
-            }
-        }
+    pub fn package_bytes(&self) -> &[u8] {
+        &self.package_bytes
     }
 }