git.delta.rocks / jrsonnet / refs/commits / bf70e2e2a045

1use crate::{2	error::{Error::*, Result},3	throw,4};5use fs::File;6use jrsonnet_interner::IStr;7use std::fs;8use std::io::Read;9use std::{10	any::Any,11	cell::RefCell,12	collections::HashMap,13	path::{Path, PathBuf},14	rc::Rc,15};1617/// Implements file resolution logic for `import` and `importStr`18pub trait ImportResolver {19	/// Resolves real file path, e.g. `(/home/user/manifests, b.libjsonnet)` can correspond20	/// both to `/home/user/manifests/b.libjsonnet` and to `/home/user/${vendor}/b.libjsonnet`21	/// where `${vendor}` is a library path.22	fn resolve_file(&self, from: &Path, path: &Path) -> Result<Rc<Path>>;2324	/// Reads file from filesystem, should be used only with path received from `resolve_file`25	fn load_file_contents(&self, resolved: &Path) -> Result<IStr>;2627	/// # Safety28	///29	/// For use only in bindings, should not be used elsewhere.30	/// Implementations which are not intended to be used in bindings31	/// should panic on call to this method.32	unsafe fn as_any(&self) -> &dyn Any;33}3435/// Dummy resolver, can't resolve/load any file36pub struct DummyImportResolver;37impl ImportResolver for DummyImportResolver {38	fn resolve_file(&self, from: &Path, path: &Path) -> Result<Rc<Path>> {39		throw!(ImportNotSupported(from.into(), path.into()))40	}4142	fn load_file_contents(&self, _resolved: &Path) -> Result<IStr> {43		// Can be only caused by library direct consumer, not by supplied jsonnet44		panic!("dummy resolver can't load any file")45	}4647	unsafe fn as_any(&self) -> &dyn Any {48		panic!("`as_any($self)` is not supported by dummy resolver")49	}50}51#[allow(clippy::use_self)]52impl Default for Box<dyn ImportResolver> {53	fn default() -> Self {54		Box::new(DummyImportResolver)55	}56}5758/// File resolver, can load file from both FS and library paths59#[derive(Default)]60pub struct FileImportResolver {61	/// Library directories to search for file.62	/// Referred to as `jpath` in original jsonnet implementation.63	pub library_paths: Vec<PathBuf>,64}65impl ImportResolver for FileImportResolver {66	fn resolve_file(&self, from: &Path, path: &Path) -> Result<Rc<Path>> {67		let mut direct = from.to_path_buf();68		direct.push(path);69		if direct.exists() {70			Ok(direct.into())71		} else {72			for library_path in self.library_paths.iter() {73				let mut cloned = library_path.clone();74				cloned.push(path);75				if cloned.exists() {76					return Ok(cloned.into());77				}78			}79			throw!(ImportFileNotFound(from.to_owned(), path.to_owned()))80		}81	}82	fn load_file_contents(&self, id: &Path) -> Result<IStr> {83		let mut file = File::open(id).map_err(|_e| ResolvedFileNotFound(id.to_owned()))?;84		let mut out = String::new();85		file.read_to_string(&mut out)86			.map_err(|_e| ImportBadFileUtf8(id.to_owned()))?;87		Ok(out.into())88	}89	unsafe fn as_any(&self) -> &dyn Any {90		panic!("this resolver can't be used as any")91	}92}9394type ResolutionData = (PathBuf, PathBuf);9596/// Caches results of the underlying resolver97pub struct CachingImportResolver {98	resolution_cache: RefCell<HashMap<ResolutionData, Result<Rc<Path>>>>,99	loading_cache: RefCell<HashMap<PathBuf, Result<IStr>>>,100	inner: Box<dyn ImportResolver>,101}102impl ImportResolver for CachingImportResolver {103	fn resolve_file(&self, from: &Path, path: &Path) -> Result<Rc<Path>> {104		self.resolution_cache105			.borrow_mut()106			.entry((from.to_owned(), path.to_owned()))107			.or_insert_with(|| self.inner.resolve_file(from, path))108			.clone()109	}110111	fn load_file_contents(&self, resolved: &Path) -> Result<IStr> {112		self.loading_cache113			.borrow_mut()114			.entry(resolved.to_owned())115			.or_insert_with(|| self.inner.load_file_contents(resolved))116			.clone()117	}118	unsafe fn as_any(&self) -> &dyn Any {119		panic!("this resolver can't be used as any")120	}121}