git.delta.rocks / jrsonnet / refs/commits / 0afc5f71ec0d

1use crate::create_error;2use crate::error::{Error, Result};3use fs::File;4use std::fs;5use std::io::Read;6use std::{cell::RefCell, collections::HashMap, path::PathBuf, rc::Rc};78pub trait ImportResolver {9	fn resolve_file(&self, from: &PathBuf, path: &PathBuf) -> Result<Rc<PathBuf>>;10	fn load_file_contents(&self, resolved: &PathBuf) -> Result<Rc<str>>;11}1213pub struct DummyImportResolver;14impl ImportResolver for DummyImportResolver {15	fn resolve_file(&self, from: &PathBuf, path: &PathBuf) -> Result<Rc<PathBuf>> {16		create_error(Error::ImportNotSupported(from.clone(), path.clone()))17	}18	fn load_file_contents(&self, _resolved: &PathBuf) -> Result<Rc<str>> {19		// Can be only caused by library direct consumer, not by supplied jsonnet20		panic!("dummy resolver can't load any file")21	}22}23impl Default for Box<dyn ImportResolver> {24	fn default() -> Self {25		Box::new(DummyImportResolver)26	}27}2829pub struct FileImportResolver {30	pub library_paths: Vec<PathBuf>,31}32impl ImportResolver for FileImportResolver {33	fn resolve_file(&self, from: &PathBuf, path: &PathBuf) -> Result<Rc<PathBuf>> {34		let mut new_path = from.clone();35		new_path.push(path);36		if new_path.exists() {37			Ok(Rc::new(new_path))38		} else {39			for library_path in self.library_paths.iter() {40				let mut cloned = library_path.clone();41				cloned.push(path);42				if cloned.exists() {43					return Ok(Rc::new(cloned));44				}45			}46			create_error(Error::ImportFileNotFound(from.clone(), path.clone()))47		}48	}49	fn load_file_contents(&self, id: &PathBuf) -> Result<Rc<str>> {50		let mut file = File::open(id).map_err(|_e| {51			create_error::<()>(Error::ResolvedFileNotFound(id.clone()))52				.err()53				.unwrap()54		})?;55		let mut out = String::new();56		file.read_to_string(&mut out).map_err(|_e| {57			create_error::<()>(Error::ImportBadFileUtf8(id.clone()))58				.err()59				.unwrap()60		})?;61		Ok(out.into())62	}63}6465pub struct CachingImportResolver {66	resolution_cache: RefCell<HashMap<(PathBuf, PathBuf), Result<Rc<PathBuf>>>>,67	loading_cache: RefCell<HashMap<PathBuf, Result<Rc<str>>>>,68	inner: Box<dyn ImportResolver>,69}70impl ImportResolver for CachingImportResolver {71	fn resolve_file(&self, from: &PathBuf, path: &PathBuf) -> Result<Rc<PathBuf>> {72		self.resolution_cache73			.borrow_mut()74			.entry((from.clone(), path.clone()))75			.or_insert_with(|| self.inner.resolve_file(from, path))76			.clone()77	}78	fn load_file_contents(&self, resolved: &PathBuf) -> Result<Rc<str>> {79		self.loading_cache80			.borrow_mut()81			.entry(resolved.clone())82			.or_insert_with(|| self.inner.load_file_contents(resolved))83			.clone()84	}85}