Initial Book loader and summary parsing

Cargo.toml

@@ -41,6 +41,7 @@ ws = { version = "0.7", optional = true}
 # Tests
 [dev-dependencies]
 tempdir = "0.3.4"
+pretty_assertions = "0.2.1"
 
 [build-dependencies]
 error-chain = "0.10"

src/lib.rs

@@ -76,19 +76,24 @@ extern crate serde_derive;
 extern crate serde;
 #[macro_use] 
 extern crate serde_json;
+#[macro_use]
+extern crate log;
 
 extern crate handlebars;
 extern crate pulldown_cmark;
 extern crate regex;
 
+#[cfg(test)]
 #[macro_use]
-extern crate log;
+extern crate pretty_assertions;
+
 pub mod book;
 pub mod config;
 mod parse;
 pub mod renderer;
 pub mod theme;
 pub mod utils;
+pub mod loader;
 
 pub use book::MDBook;
 pub use book::BookItem;

src/loader/mod.rs

@@ -0,0 +1,84 @@
+//! Functionality for loading the internal book representation from disk.
+//!
+//! The typical use case is to create a `Loader` pointing at the correct
+//! source directory then call the `load()` method. Internally this will
+//! search for the `SUMMARY.md` file, parse it, then use the parsed
+//! `Summary` to construct an in-memory representation of the entire book.
+//!
+//! # Examples
+//!
+//! ```rust,no_run
+//! # fn run() -> mdbook::errors::Result<()> {
+//! use mdbook::loader::Loader;
+//! let loader = Loader::new("./src/");
+//! let book = loader.load()?;
+//! # Ok(())
+//! # }
+//! # fn main() { run().unwrap() }
+//! ```
+//!
+//! Alternatively, if you are using the `mdbook` crate as a library and
+//! only want to read the `SUMMARY.md` file without having to load the
+//! entire book from disk, you can use the `parse_summary()` function.
+//!
+//! ```rust
+//! # fn run() -> mdbook::errors::Result<()> {
+//! use mdbook::loader::parse_summary;
+//! let src = "# Book Summary
+//!
+//! [Introduction](./index.md)
+//! - [First Chapter](./first/index.md)
+//!   - [Sub-Section](./first/subsection.md)
+//! - [Second Chapter](./second/index.md)
+//! ";
+//! let summary = parse_summary(src)?;
+//! println!("{:#?}", summary);
+//! # Ok(())
+//! # }
+//! # fn main() { run().unwrap() }
+//! ```
+
+#![deny(missing_docs)]
+
+use std::path::{Path, PathBuf};
+use std::fs::File;
+use std::io::Read;
+use errors::*;
+
+mod summary;
+
+pub use self::summary::{Summary, Link, SummaryItem, parse_summary, SectionNumber};
+
+
+/// The object in charge of parsing the source directory into a usable
+/// `Book` struct.
+#[derive(Debug, Clone, PartialEq)]
+pub struct Loader {
+    source_directory: PathBuf,
+}
+
+impl Loader {
+    /// Create a new loader which uses the provided source directory.
+    pub fn new<P: AsRef<Path>>(source_directory: P) -> Loader {
+        Loader { source_directory: source_directory.as_ref().to_path_buf() }
+    }
+
+    /// Parse the summary file and use it to load a book from disk.
+    pub fn load(&self) -> Result<()> {
+        let summary = self.parse_summary().chain_err(
+            || "Couldn't parse `SUMMARY.md`",
+        )?;
+
+        unimplemented!()
+    }
+
+    /// Parse the `SUMMARY.md` file.
+    pub fn parse_summary(&self) -> Result<Summary> {
+        let path = self.source_directory.join("SUMMARY.md");
+
+        let mut summary_content = String::new();
+        File::open(&path)?.read_to_string(&mut summary_content)?;
+
+        summary::parse_summary(&summary_content)
+    }
+}