print current rust version on the about page

src/docbuilder/chroot_builder.rs

@@ -11,7 +11,7 @@ use std::process::Command;
 use std::path::PathBuf;
 use std::fs::remove_dir_all;
 use postgres::Connection;
-use rustc_serialize::json::Json;
+use rustc_serialize::json::{Json, ToJson};
 use error::Result;
 
 
@@ -314,7 +314,7 @@ impl DocBuilder {
 
 
     /// Gets rustc and cratesfyi version from chroot environment
-    fn get_versions(&self) -> (String, String) {
+    pub fn get_versions(&self) -> (String, String) {
         // It is safe to use expect here
         // chroot environment must always have rustc and cratesfyi installed
         (String::from(self.chroot_command("rustc --version")
@@ -439,6 +439,15 @@ impl DocBuilder {
 
         try!(self.clean(&pkg));
 
+        let (vers, _) = self.get_versions();
+
+        try!(conn.query("INSERT INTO config (name, value) VALUES ('rustc_version', $1)",
+                   &[&vers.to_json()])
+            .or_else(|_| {
+                conn.query("UPDATE config SET value = $1 WHERE name = 'rustc_version'",
+                           &[&vers.to_json()])
+            }));
+
         Ok(())
     }
 }

src/web/mod.rs

@@ -61,7 +61,6 @@ use semver::{Version, VersionReq};
 use rustc_serialize::json::{Json, ToJson};
 use std::collections::BTreeMap;
 
-
 /// Duration of static files for staticfile and DatabaseFileHandler (in seconds)
 const STATIC_FILE_CACHE_DURATION: u64 = 60 * 60 * 24 * 30 * 12;   // 12 months
 const STYLE_CSS: &'static str = include_str!(concat!(env!("OUT_DIR"), "/style.css"));
@@ -97,9 +96,7 @@ impl CratesfyiHandler {
         let mut router = Router::new();
         router.get("/", releases::home_page, "index");
         router.get("/style.css", style_css_handler, "style_css");
-        router.get("/about",
-                   |_: &mut Request| page::Page::new(false).title("About Docs.rs").to_resp("about"),
-                   "about");
+        router.get("/about", sitemap::about_handler, "about");
         router.get("/robots.txt", sitemap::robots_txt_handler, "robots_txt");
         router.get("/sitemap.xml", sitemap::sitemap_handler, "sitemap_xml");
         router.get("/opensearch.xml", opensearch_xml_handler, "opensearch_xml");
@@ -427,7 +424,6 @@ fn opensearch_xml_handler(_: &mut Request) -> IronResult<Response> {
     Ok(response)
 }
 
-
 /// MetaData used in header
 #[derive(Debug)]
 pub struct MetaData {

src/web/sitemap.rs

@@ -1,11 +1,11 @@
-
-
+use std::collections::BTreeMap;
 use iron::prelude::*;
 use iron::headers::ContentType;
+use rustc_serialize::json::Json;
 use super::page::Page;
 use super::pool::Pool;
 use time;
-
+use db::connect_db;
 
 pub fn sitemap_handler(req: &mut Request) -> IronResult<Response> {
     let conn = extension!(req, Pool);
@@ -31,3 +31,20 @@ pub fn robots_txt_handler(_: &mut Request) -> IronResult<Response> {
     resp.headers.set(ContentType("text/plain".parse().unwrap()));
     Ok(resp)
 }
+
+pub fn about_handler(req: &mut Request) -> IronResult<Response> {
+    let mut content = BTreeMap::new();
+
+    let conn = extension!(req, Pool);
+    let res = ctry!(conn.query("SELECT value FROM config WHERE name = 'rustc_version'", &[]));
+
+    if let Some(row) = res.iter().next() {
+        if let Some(Ok::<Json, _>(res)) = row.get_opt(0) {
+            if let Some(vers) = res.as_string() {
+                content.insert("rustc_version".to_string(), vers.to_string());
+            }
+        }
+    }
+
+    Page::new(content).title("About Docs.rs").to_resp("about")
+}

templates/about.hbs

@@ -10,6 +10,12 @@
   Docs.rs automatically builds crates' documentation released on
   <a href="https://crates.io/">crates.io</a>
   using the nightly release of the Rust compiler.
+  {{#if content.rustc_version}}
+  The current version of the Rust compiler in use is <code>{{content.rustc_version}}</code>.
+  If you need a newer version of this compiler, check the
+  <a href="https://github.com/rust-lang/docs.rs/issues">issues page</a>
+  and file a new issue if you don't see an existing request.
+  {{/if}}
   </p>
 
   <p>