Validate target environments

Cargo.toml

@@ -55,6 +55,7 @@ spin-app = { path = "crates/app" }
 spin-build = { path = "crates/build" }
 spin-common = { path = "crates/common" }
 spin-doctor = { path = "crates/doctor" }
+spin-environments = { path = "crates/environments" }
 spin-factor-outbound-networking = { path = "crates/factor-outbound-networking" }
 spin-http = { path = "crates/http" }
 spin-loader = { path = "crates/loader" }

crates/build/Cargo.toml

@@ -8,6 +8,7 @@ edition = { workspace = true }
 anyhow = { workspace = true }
 serde = { workspace = true }
 spin-common = { path = "../common" }
+spin-environments = { path = "../environments" }
 spin-manifest = { path = "../manifest" }
 subprocess = "0.2"
 terminal = { path = "../terminal" }

crates/build/src/lib.rs

@@ -16,31 +16,87 @@ use subprocess::{Exec, Redirection};
 use crate::manifest::component_build_configs;
 
 /// If present, run the build command of each component.
-pub async fn build(manifest_file: &Path, component_ids: &[String]) -> Result<()> {
-    let (components, manifest_err) =
-        component_build_configs(manifest_file)
-            .await
-            .with_context(|| {
-                format!(
-                    "Cannot read manifest file from {}",
-                    quoted_path(manifest_file)
-                )
-            })?;
+pub async fn build(
+    manifest_file: &Path,
+    component_ids: &[String],
+    target_checks: TargetChecking,
+    cache_root: Option<PathBuf>,
+) -> Result<()> {
+    let build_info = component_build_configs(manifest_file)
+        .await
+        .with_context(|| {
+            format!(
+                "Cannot read manifest file from {}",
+                quoted_path(manifest_file)
+            )
+        })?;
     let app_dir = parent_dir(manifest_file)?;
 
-    let build_result = build_components(component_ids, components, app_dir);
+    let build_result = build_components(component_ids, build_info.components(), &app_dir);
 
-    if let Some(e) = manifest_err {
+    // Emit any required warnings now, so that they don't bury any errors.
+    if let Some(e) = build_info.load_error() {
+        // The manifest had errors. We managed to attempt a build anyway, but we want to
+        // let the user know about them.
         terminal::warn!("The manifest has errors not related to the Wasm component build. Error details:\n{e:#}");
+        // Checking deployment targets requires a healthy manifest (because trigger types etc.),
+        // if any of these were specified, warn they are being skipped.
+        let should_have_checked_targets =
+            target_checks.check() && build_info.has_deployment_targets();
+        if should_have_checked_targets {
+            terminal::warn!(
+                "The manifest error(s) prevented Spin from checking the deployment targets."
+            );
+        }
+    }
+
+    // If the build failed, exit with an error at this point.
+    build_result?;
+
+    let Some(manifest) = build_info.manifest() else {
+        // We can't proceed to checking (because that needs a full healthy manifest), and we've
+        // already emitted any necessary warning, so quit.
+        return Ok(());
+    };
+
+    if target_checks.check() {
+        let application = spin_environments::ApplicationToValidate::new(
+            manifest.clone(),
+            manifest_file.parent().unwrap(),
+        )
+        .await
+        .context("unable to load application for checking against deployment targets")?;
+        let target_validation = spin_environments::validate_application_against_environment_ids(
+            &application,
+            build_info.deployment_targets(),
+            cache_root.clone(),
+            &app_dir,
+        )
+        .await
+        .context("unable to check if the application is compatible with deployment targets")?;
+
+        if !target_validation.is_ok() {
+            for error in target_validation.errors() {
+                terminal::error!("{error}");
+            }
+            anyhow::bail!("All components built successfully, but one or more was incompatible with one or more of the deployment targets.");
+        }
     }
 
-    build_result
+    Ok(())
+}
+
+/// Run all component build commands, using the default options (build all
+/// components, perform target checking). We run a "default build" in several
+/// places and this centralises the logic of what such a "default build" means.
+pub async fn build_default(manifest_file: &Path, cache_root: Option<PathBuf>) -> Result<()> {
+    build(manifest_file, &[], TargetChecking::Check, cache_root).await
 }
 
 fn build_components(
     component_ids: &[String],
     components: Vec<ComponentBuildInfo>,
-    app_dir: PathBuf,
+    app_dir: &Path,
 ) -> Result<(), anyhow::Error> {
     let components_to_build = if component_ids.is_empty() {
         components
@@ -70,7 +126,7 @@ fn build_components(
 
     components_to_build
         .into_iter()
-        .map(|c| build_component(c, &app_dir))
+        .map(|c| build_component(c, app_dir))
         .collect::<Result<Vec<_>, _>>()?;
 
     terminal::step!("Finished", "building all Spin components");
@@ -159,6 +215,21 @@ fn construct_workdir(app_dir: &Path, workdir: Option<impl AsRef<Path>>) -> Resul
     Ok(cwd)
 }
 
+/// Specifies target environment checking behaviour
+pub enum TargetChecking {
+    /// The build should check that all components are compatible with all target environments.
+    Check,
+    /// The build should not check target environments.
+    Skip,
+}
+
+impl TargetChecking {
+    /// Should the build check target environments?
+    fn check(&self) -> bool {
+        matches!(self, Self::Check)
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -171,6 +242,8 @@ mod tests {
     #[tokio::test]
     async fn can_load_even_if_trigger_invalid() {
         let bad_trigger_file = test_data_root().join("bad_trigger.toml");
-        build(&bad_trigger_file, &[]).await.unwrap();
+        build(&bad_trigger_file, &[], TargetChecking::Skip, None)
+            .await
+            .unwrap();
     }
 }

crates/build/src/manifest.rs

@@ -4,37 +4,120 @@ use std::{collections::BTreeMap, path::Path};
 
 use spin_manifest::{schema::v2, ManifestVersion};
 
+#[allow(clippy::large_enum_variant)] // only ever constructed once
+pub enum ManifestBuildInfo {
+    Loadable {
+        components: Vec<ComponentBuildInfo>,
+        deployment_targets: Vec<spin_manifest::schema::v2::TargetEnvironmentRef>,
+        manifest: spin_manifest::schema::v2::AppManifest,
+    },
+    Unloadable {
+        components: Vec<ComponentBuildInfo>,
+        has_deployment_targets: bool,
+        load_error: spin_manifest::Error,
+    },
+}
+
+impl ManifestBuildInfo {
+    pub fn components(&self) -> Vec<ComponentBuildInfo> {
+        match self {
+            Self::Loadable { components, .. } => components.clone(),
+            Self::Unloadable { components, .. } => components.clone(),
+        }
+    }
+
+    pub fn load_error(&self) -> Option<&spin_manifest::Error> {
+        match self {
+            Self::Loadable { .. } => None,
+            Self::Unloadable { load_error, .. } => Some(load_error),
+        }
+    }
+
+    pub fn deployment_targets(&self) -> &[spin_manifest::schema::v2::TargetEnvironmentRef] {
+        match self {
+            Self::Loadable {
+                deployment_targets, ..
+            } => deployment_targets,
+            Self::Unloadable { .. } => &[],
+        }
+    }
+
+    pub fn has_deployment_targets(&self) -> bool {
+        match self {
+            Self::Loadable {
+                deployment_targets, ..
+            } => !deployment_targets.is_empty(),
+            Self::Unloadable {
+                has_deployment_targets,
+                ..
+            } => *has_deployment_targets,
+        }
+    }
+
+    pub fn manifest(&self) -> Option<&spin_manifest::schema::v2::AppManifest> {
+        match self {
+            Self::Loadable { manifest, .. } => Some(manifest),
+            Self::Unloadable { .. } => None,
+        }
+    }
+}
+
 /// Returns a map of component IDs to [`v2::ComponentBuildConfig`]s for the
 /// given (v1 or v2) manifest path. If the manifest cannot be loaded, the
 /// function attempts fallback: if fallback succeeds, result is Ok but the load error
 /// is also returned via the second part of the return value tuple.
-pub async fn component_build_configs(
-    manifest_file: impl AsRef<Path>,
-) -> Result<(Vec<ComponentBuildInfo>, Option<spin_manifest::Error>)> {
+pub async fn component_build_configs(manifest_file: impl AsRef<Path>) -> Result<ManifestBuildInfo> {
     let manifest = spin_manifest::manifest_from_file(&manifest_file);
     match manifest {
-        Ok(manifest) => Ok((build_configs_from_manifest(manifest), None)),
-        Err(e) => fallback_load_build_configs(&manifest_file)
-            .await
-            .map(|bc| (bc, Some(e))),
+        Ok(mut manifest) => {
+            spin_manifest::normalize::normalize_manifest(&mut manifest);
+            let components = build_configs_from_manifest(&manifest);
+            let deployment_targets = deployment_targets_from_manifest(&manifest);
+            Ok(ManifestBuildInfo::Loadable {
+                components,
+                deployment_targets,
+                manifest,
+            })
+        }
+        Err(load_error) => {
+            // The manifest didn't load, but the problem might not be build-affecting.
+            // Try to fall back by parsing out only the bits we need. And if something
+            // goes wrong with the fallback, give up and return the original manifest load
+            // error.
+            let Ok(components) = fallback_load_build_configs(&manifest_file).await else {
+                return Err(load_error.into());
+            };
+            let Ok(has_deployment_targets) = has_deployment_targets(&manifest_file).await else {
+                return Err(load_error.into());
+            };
+            Ok(ManifestBuildInfo::Unloadable {
+                components,
+                has_deployment_targets,
+                load_error,
+            })
+        }
     }
 }
 
 fn build_configs_from_manifest(
-    mut manifest: spin_manifest::schema::v2::AppManifest,
+    manifest: &spin_manifest::schema::v2::AppManifest,
 ) -> Vec<ComponentBuildInfo> {
-    spin_manifest::normalize::normalize_manifest(&mut manifest);
-
     manifest
         .components
-        .into_iter()
+        .iter()
         .map(|(id, c)| ComponentBuildInfo {
             id: id.to_string(),
-            build: c.build,
+            build: c.build.clone(),
         })
         .collect()
 }
 
+fn deployment_targets_from_manifest(
+    manifest: &spin_manifest::schema::v2::AppManifest,
+) -> Vec<spin_manifest::schema::v2::TargetEnvironmentRef> {
+    manifest.application.targets.clone()
+}
+
 async fn fallback_load_build_configs(
     manifest_file: impl AsRef<Path>,
 ) -> Result<Vec<ComponentBuildInfo>> {
@@ -57,7 +140,23 @@ async fn fallback_load_build_configs(
     })
 }
 
-#[derive(Deserialize)]
+async fn has_deployment_targets(manifest_file: impl AsRef<Path>) -> Result<bool> {
+    let manifest_text = tokio::fs::read_to_string(manifest_file).await?;
+    Ok(match ManifestVersion::detect(&manifest_text)? {
+        ManifestVersion::V1 => false,
+        ManifestVersion::V2 => {
+            let table: toml::value::Table = toml::from_str(&manifest_text)?;
+            table
+                .get("application")
+                .and_then(|a| a.as_table())
+                .and_then(|t| t.get("targets"))
+                .and_then(|arr| arr.as_array())
+                .is_some_and(|arr| !arr.is_empty())
+        }
+    })
+}
+
+#[derive(Clone, Deserialize)]
 pub struct ComponentBuildInfo {
     #[serde(default)]
     pub id: String,