Refactoring of robotparser-rs

.gitignore

@@ -1,3 +1,4 @@
 target
 Cargo.lock
 .vscode/
+.idea/

Cargo.toml

@@ -8,16 +8,25 @@ license = "MIT"
 name = "robotparser"
 readme = "README.md"
 repository = "https://github.com/messense/robotparser-rs"
-version = "0.10.2"
+version = "0.11.0"
+edition = "2018"
 
 [dependencies]
-url = "1"
+url = "2"
+percent-encoding = "2.1"
 
 [dependencies.reqwest]
-version = "0.9"
+version = "0.10.1"
+optional = true
+features = ["blocking"]
+
+[dependencies.futures]
+version = "0.3"
 optional = true
 
 [features]
-default = ["http"]
-http = ["reqwest"]
+default = ["reqwest", "futures"]
 unstable = []
+
+[dev-dependencies]
+tokio = "0.2.11"

README.md

@@ -15,7 +15,7 @@ Add it to your ``Cargo.toml``:
 
 ```toml
 [dependencies]
-robotparser = "0.10"
+robotparser = "0.11"
 ```
 
 Add ``extern crate robotparser`` to your crate root and your're good to go!
@@ -24,14 +24,17 @@ Add ``extern crate robotparser`` to your crate root and your're good to go!
 ## Examples
 
 ```rust
-extern crate robotparser;
-
-use robotparser::RobotFileParser;
+use robotparser::http::RobotsTxtClient;
+use robotparser::service::RobotsTxtService;
+use reqwest::Client;
+use url::Url;
 
 fn main() {
-    let parser = RobotFileParser::new("http://www.python.org/robots.txt");
-    parser.read();
-    assert!(parser.can_fetch("*", "http://www.python.org/robots.txt"));
+    let client = Client::new();
+    let robots_txt_url = Url::parse("http://www.python.org/robots.txt").unwrap();
+    let robots_txt = client.fetch_robots_txt(robots_txt_url.origin()).unwrap().get_result();
+    let fetch_url = Url::parse("http://www.python.org/robots.txt").unwrap();
+    assert!(robots_txt.can_fetch("*", &fetch_url));
 }
 ```
 

src/http.rs

@@ -0,0 +1,19 @@
+//! # Supported libraries
+//! To enable support for the required library, you need to add this feature to your `Cargo.toml`.
+//! Now only one library is supported - `reqwest`.
+//! But you can also add support for other libraries.
+
+use url::Origin;
+#[cfg(feature = "reqwest")]
+/// Support for reqwest library.
+pub mod reqwest;
+
+/// User agent of this crate.
+pub const DEFAULT_USER_AGENT: &str = "robotparser-rs (https://crates.io/crates/robotparser)";
+
+/// Trait to fetch and parse the robots.txt file.
+/// Must be implemented on http-client.
+pub trait RobotsTxtClient {
+    type Result;
+    fn fetch_robots_txt(&self, origin: Origin) -> Self::Result;
+}

src/http/reqwest.rs

@@ -0,0 +1,4 @@
+mod sync_reqwest;
+pub use self::sync_reqwest::*;
+mod async_reqwest;
+pub use self::async_reqwest::*;

src/http/reqwest/async_reqwest.rs

@@ -0,0 +1,76 @@
+use reqwest::{Client, Request};
+use reqwest::{Method, Error};
+use reqwest::header::HeaderValue;
+use url::{Origin, Url};
+use reqwest::header::USER_AGENT;
+use crate::http::{RobotsTxtClient, DEFAULT_USER_AGENT};
+use crate::parser::{ParseResult, parse_fetched_robots_txt};
+use crate::model::FetchedRobotsTxt;
+use std::pin::Pin;
+use futures::task::{Context, Poll};
+use futures::Future;
+use futures::future::TryFutureExt;
+use futures::future::ok as future_ok;
+
+type FetchFuture = Box<dyn Future<Output=Result<(ResponseInfo, String), Error>>>;
+
+impl RobotsTxtClient for Client {
+    type Result = RobotsTxtResponse;
+    fn fetch_robots_txt(&self, origin: Origin) -> Self::Result {
+        let url = format!("{}/robots.txt", origin.unicode_serialization());
+        let url = Url::parse(&url).expect("Unable to parse robots.txt url");
+        let mut request = Request::new(Method::GET, url);
+        let _ = request.headers_mut().insert(USER_AGENT, HeaderValue::from_static(DEFAULT_USER_AGENT));
+        let response = self
+            .execute(request)
+            .and_then(|response| {
+                let response_info = ResponseInfo {status_code: response.status().as_u16()};
+                return response.text().and_then(|response_text| {
+                    return future_ok((response_info, response_text));
+                });
+            });
+        let response: Pin<Box<dyn Future<Output=Result<(ResponseInfo, String), Error>>>> = Box::pin(response);
+        return RobotsTxtResponse {
+            origin,
+            response,
+        }
+    }
+}
+
+struct ResponseInfo {
+    status_code: u16,
+}
+
+/// Future for fetching robots.txt result.
+pub struct RobotsTxtResponse {
+    origin: Origin,
+    response: Pin<FetchFuture>,
+}
+
+impl RobotsTxtResponse {
+    /// Returns origin of robots.txt
+    pub fn get_origin(&self) -> &Origin {
+        return &self.origin;
+    }
+}
+
+impl Future for RobotsTxtResponse {
+    type Output = Result<ParseResult<FetchedRobotsTxt>, Error>;
+
+    fn poll(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> {
+        let self_mut = self.get_mut();
+        let response_pin = self_mut.response.as_mut();
+        match response_pin.poll(cx) {
+            Poll::Ready(Ok((response_info, text))) => {
+                let robots_txt = parse_fetched_robots_txt(self_mut.origin.clone(), response_info.status_code, &text);
+                return Poll::Ready(Ok(robots_txt));
+            },
+            Poll::Ready(Err(error)) => {
+                return Poll::Ready(Err(error));
+            },
+            Poll::Pending => {
+                return Poll::Pending;
+            },
+        }
+    }
+}

src/http/reqwest/sync_reqwest.rs

@@ -0,0 +1,23 @@
+use reqwest::blocking::{Client, Request};
+use reqwest::{Method, Error};
+use reqwest::header::HeaderValue;
+use url::{Origin, Url};
+use reqwest::header::USER_AGENT;
+use crate::http::{RobotsTxtClient, DEFAULT_USER_AGENT};
+use crate::parser::{ParseResult, parse_fetched_robots_txt};
+use crate::model::FetchedRobotsTxt;
+
+impl RobotsTxtClient for Client {
+    type Result = Result<ParseResult<FetchedRobotsTxt>, Error>;
+    fn fetch_robots_txt(&self, origin: Origin) -> Self::Result {
+        let url = format!("{}/robots.txt", origin.unicode_serialization());
+        let url = Url::parse(&url).expect("Unable to parse robots.txt url");
+        let mut request = Request::new(Method::GET, url);
+        let _ = request.headers_mut().insert(USER_AGENT, HeaderValue::from_static(DEFAULT_USER_AGENT));
+        let response = self.execute(request)?;
+        let status_code = response.status().as_u16();
+        let text = response.text()?;
+        let robots_txt = parse_fetched_robots_txt(origin, status_code, &text);
+        return Ok(robots_txt);
+    }
+}