RFC updates: unify the specialisation documents into the root doc

bootspec/src/lib.rs

@@ -12,17 +12,6 @@ pub struct SpecialisationName(pub String);
 /// A wrapper type describing the root directory of a NixOS system configuration.
 pub struct SystemConfigurationRoot(pub PathBuf);
 
-#[derive(Debug, Default, Clone, Deserialize, Serialize, PartialEq, Eq)]
-/// A wrapper type describing the path to the bootspec schema file.
-pub struct BootSpecPath(pub PathBuf);
-
-#[derive(Debug, Default, Clone, Deserialize, Serialize, PartialEq, Eq)]
-/// Provides the information necessary to consume a specialisation with or without a bootspec.
-pub struct SpecialisationDescription {
-    /// The optional path to the specialisation's bootspec.
-    pub bootspec: BootSpecPath,
-}
-
 // !!! IMPORTANT: KEEP `BootJson`, `SCHEMA_VERSION`, and `JSON_FILENAME` IN SYNC !!!
 /// The current bootspec schema.
 pub type BootJson = v1::BootJsonV1;

bootspec/src/v1.rs

@@ -3,7 +3,7 @@ use std::path::PathBuf;
 
 use serde::{Deserialize, Serialize};
 
-use crate::{SpecialisationDescription, SpecialisationName, SystemConfigurationRoot};
+use crate::{SpecialisationName, SystemConfigurationRoot};
 
 /// The V1 bootspec schema version.
 pub const SCHEMA_VERSION: u32 = 1;
@@ -29,7 +29,7 @@ pub struct BootJsonV1 {
     /// Path to "append-initrd-secrets" script -- $toplevel/append-initrd-secrets
     pub initrd_secrets: Option<PathBuf>,
     /// Mapping of specialisation names to their boot.json
-    pub specialisation: HashMap<SpecialisationName, SpecialisationDescription>,
+    pub specialisation: HashMap<SpecialisationName, BootJsonV1>,
     /// config.system.build.toplevel path
     pub toplevel: SystemConfigurationRoot,
 }

synthesize/integration-test-cases/expected-synthesis/21.11-specialisations.json

@@ -0,0 +1,29 @@
+{
+  "schemaVersion": 1,
+  "label": "NixOS 21.11pre-git (Linux 5.10.81)",
+  "kernel": "/nix/store/hprwry55jwyd71ng7v7c2rhk3a3z1im8-linux-5.10.81/bzImage",
+  "kernelParams": [
+    "loglevel=4",
+    "net.ifnames=0"
+  ],
+  "init": "/nix/store/kgkjwhscv52r2y1ha1y19lb9h4j3lfrc-nixos-system-nixos-21.11pre-git/init",
+  "initrd": "/nix/store/69bhfdfv77y0vclnlxqrd8pxjzbkz47w-initrd-linux-5.10.81/initrd",
+  "initrdSecrets": "/nix/store/kgkjwhscv52r2y1ha1y19lb9h4j3lfrc-nixos-system-nixos-21.11pre-git/append-initrd-secrets",
+  "specialisation": {
+    "example": {
+      "schemaVersion": 1,
+      "label": "NixOS 21.11pre-git (Linux 5.10.81)",
+      "kernel": "/nix/store/hprwry55jwyd71ng7v7c2rhk3a3z1im8-linux-5.10.81/bzImage",
+      "kernelParams": [
+        "loglevel=4",
+        "net.ifnames=0"
+      ],
+      "init": "/nix/store/3w5kr91xq46638fd310q2sa9mjm6r6hn-nixos-system-nixos-21.11pre-git/init",
+      "initrd": "/nix/store/69bhfdfv77y0vclnlxqrd8pxjzbkz47w-initrd-linux-5.10.81/initrd",
+      "initrdSecrets": "/nix/store/3w5kr91xq46638fd310q2sa9mjm6r6hn-nixos-system-nixos-21.11pre-git/append-initrd-secrets",
+      "specialisation": {},
+      "toplevel": "/nix/store/3w5kr91xq46638fd310q2sa9mjm6r6hn-nixos-system-nixos-21.11pre-git"
+    }
+  },
+  "toplevel": "/nix/store/kgkjwhscv52r2y1ha1y19lb9h4j3lfrc-nixos-system-nixos-21.11pre-git"
+}

synthesize/integration-test-cases/verify.sh

@@ -12,7 +12,7 @@ done) | xargs --max-procs=$(nproc) --max-lines=1 nix-build
 rm -rf generated-synthesis
 mkdir generated-synthesis
 for out in ./builds/*; do
-    cargo run --bin synthesize -- "$out" "./generated-synthesis/$(basename "$out")"
+    cargo run --bin synthesize -- "$out" "./generated-synthesis/$(basename "$out").json"
 done
 
 diff -r ./expected-synthesis ./generated-synthesis

synthesize/src/lib.rs

@@ -3,23 +3,16 @@ use std::error::Error;
 use std::fs;
 use std::path::Path;
 
-use bootspec::{
-    BootJson, BootSpecPath, SpecialisationDescription, SpecialisationName, SystemConfigurationRoot,
-    JSON_FILENAME, SCHEMA_VERSION,
-};
+use bootspec::{BootJson, SpecialisationName, SystemConfigurationRoot, SCHEMA_VERSION};
 
 #[doc(hidden)]
 pub type Result<T, E = Box<dyn Error + Send + Sync + 'static>> = core::result::Result<T, E>;
 
 /// Synthesize a [`BootJson`] struct from the path to a generation.
 ///
 /// This is useful when used on generations that do not have a bootspec attached to it.
-pub fn synthesize_schema_from_generation(generation: &Path, out_path: &Path) -> Result<()> {
-    fs::create_dir(&out_path)?;
-    let specialisationdir = out_path.join("specialisation");
-    let mut specialisationdir_created = false;
-
-    let mut toplevelspec = describe_system(&generation)?;
+pub fn synthesize_schema_from_generation(generation: &Path) -> Result<BootJson> {
+    let mut toplevelspec = describe_system(generation)?;
 
     if let Ok(specialisations) = fs::read_dir(generation.join("specialisation")) {
         for spec in specialisations.map(|res| res.map(|e| e.path())) {
@@ -29,45 +22,16 @@ pub fn synthesize_schema_from_generation(generation: &Path, out_path: &Path) ->
                 .ok_or("Could not get name of specialisation dir")?
                 .to_str()
                 .ok_or("Specialisation dir name was invalid UTF8")?;
-            let toplevel = fs::canonicalize(generation.join(format!("specialisation/{}", name)))?;
-
-            let boot_json_path = toplevel.join(JSON_FILENAME);
-            let boot_json_path = match boot_json_path.exists() {
-                true => boot_json_path,
-                false => {
-                    if !specialisationdir_created {
-                        fs::create_dir(&specialisationdir)?;
-                        specialisationdir_created = true;
-                    }
-
-                    let specname = specialisationdir.join(format!("{name}.json"));
-                    let subspec = describe_system(&toplevel)?;
-                    let pretty = serde_json::to_string_pretty(&subspec)
-                        .map_err(|e| format!("Failed to make pretty JSON from bootspec:\n{e}"))?;
-
-                    fs::write(&specname, pretty).map_err(|e| {
-                        format!("Failed to write JSON to '{}':\n{e}", out_path.display())
-                    })?;
-
-                    specname
-                }
-            };
+            let toplevel = fs::canonicalize(generation.join("specialisation").join(name))?;
+
             toplevelspec.specialisation.insert(
                 SpecialisationName(name.to_string()),
-                SpecialisationDescription {
-                    bootspec: BootSpecPath(boot_json_path),
-                },
+                describe_system(&toplevel)?,
             );
         }
     }
 
-    let pretty = serde_json::to_string_pretty(&toplevelspec)
-        .map_err(|e| format!("Failed to make pretty JSON from bootspec:\n{}", e))?;
-
-    fs::write(&out_path.join("boot.v1.json"), pretty)
-        .map_err(|e| format!("Failed to write JSON to '{}':\n{}", out_path.display(), e))?;
-
-    Ok(())
+    Ok(toplevelspec)
 }
 
 fn describe_system(generation: &Path) -> Result<BootJson> {

synthesize/src/main.rs

@@ -1,3 +1,4 @@
+use std::fs;
 use std::io::{self, Write};
 use std::path::PathBuf;
 
@@ -34,13 +35,19 @@ fn cli() -> Result<()> {
         .ok_or("Expected output path, got none.")?
         .parse::<PathBuf>()?;
 
-    synthesize::synthesize_schema_from_generation(&generation_dir, &out_path).map_err(|e| {
+    let spec = synthesize::synthesize_schema_from_generation(&generation_dir).map_err(|e| {
         format!(
             "Failed to synthesize bootspec for {}:\n{}",
             generation_dir.display(),
             e
         )
     })?;
 
+    let pretty = serde_json::to_string_pretty(&spec)
+        .map_err(|e| format!("Failed to make pretty JSON from bootspec:\n{}", e))?;
+
+    fs::write(&out_path, pretty)
+        .map_err(|e| format!("Failed to write JSON to '{}':\n{}", out_path.display(), e))?;
+
     Ok(())
 }