Allow navigating back to default target

The code as of the previous commit would let you navigate away from the
default, but not navigate back. This adds the default target to
`successful_targets` to add a link to the dropdown in 'Platform'.

After adding that, the link would give a 404
(because we treat paths literally when sending them to the database),
so the metadata for every crate now has to include the default target,
which allows redirecting to /:crate/:version/:module/ when visiting
/:crate/:version/:module/:default-target

Author: jyn514

src/docbuilder/rustwide_builder.rs

@@ -345,6 +345,7 @@ impl RustwideBuilder {
                         true,
                     )?;
 
+                    successful_targets.push(res.target.clone());
                     if in_target {
                         // Then build the documentation for all the targets
                         for target in TARGETS {
@@ -496,7 +497,7 @@ impl RustwideBuilder {
                 successful,
             },
             cargo_metadata,
-            target: target.unwrap_or_default().to_string(),
+            target: target.unwrap_or("x86_64-unknown-linux-gnu").to_string(),
             default_target: metadata.default_target.clone(),
         })
     }

src/web/crate_details.rs

@@ -43,7 +43,7 @@ pub struct CrateDetails {
     github_stars: Option<i32>,
     github_forks: Option<i32>,
     github_issues: Option<i32>,
-    metadata: MetaData,
+    pub metadata: MetaData,
     is_library: bool,
     doc_targets: Option<Json>,
     license: Option<String>,
@@ -120,7 +120,8 @@ impl CrateDetails {
                             releases.is_library,
                             releases.doc_targets,
                             releases.license,
-                            releases.documentation_url
+                            releases.documentation_url,
+                            releases.default_target
                      FROM releases
                      INNER JOIN crates ON releases.crate_id = crates.id
                      WHERE crates.name = $1 AND releases.version = $2;";
@@ -160,6 +161,7 @@ impl CrateDetails {
             description: rows.get(0).get(4),
             rustdoc_status: rows.get(0).get(11),
             target_name: rows.get(0).get(16),
+            default_target: rows.get(0).get(25),
         };
 
         let mut crate_details = CrateDetails {

src/web/mod.rs

@@ -451,6 +451,7 @@ pub struct MetaData {
     pub description: Option<String>,
     pub target_name: Option<String>,
     pub rustdoc_status: bool,
+    pub default_target: String,
 }
 
 
@@ -460,7 +461,8 @@ impl MetaData {
                                        releases.version,
                                        releases.description,
                                        releases.target_name,
-                                       releases.rustdoc_status
+                                       releases.rustdoc_status,
+                                       releases.default_target
                                 FROM releases
                                 INNER JOIN crates ON crates.id = releases.crate_id
                                 WHERE crates.name = $1 AND releases.version = $2",
@@ -473,6 +475,7 @@ impl MetaData {
                 description: row.get(2),
                 target_name: row.get(3),
                 rustdoc_status: row.get(4),
+                default_target: row.get(5),
             });
         }
 
@@ -489,6 +492,7 @@ impl ToJson for MetaData {
         m.insert("description".to_owned(), self.description.to_json());
         m.insert("target_name".to_owned(), self.target_name.to_json());
         m.insert("rustdoc_status".to_owned(), self.rustdoc_status.to_json());
+        m.insert("default_target".to_owned(), self.default_target.to_json());
         m.to_json()
     }
 }

src/web/rustdoc.rs

@@ -224,6 +224,14 @@ pub fn rustdoc_html_server_handler(req: &mut Request) -> IronResult<Response> {
     req_path.insert(1, &name);
     req_path.insert(2, &version);
 
+    // if visiting the full path to the default target, remove the target from the path
+    let crate_details = cexpect!(CrateDetails::new(&conn, &name, &version));
+    if req_path[3] == crate_details.metadata.default_target {
+        let canonical = Url::parse(&req_path[..2].join("/"))
+            .expect("got an invalid URL to start");
+        return Ok(super::redirect(canonical));
+    }
+
     let path = {
         let mut path = req_path.join("/");
         if path.ends_with('/') {
@@ -261,7 +269,6 @@ pub fn rustdoc_html_server_handler(req: &mut Request) -> IronResult<Response> {
     content.body_class = body_class;
 
     content.full = file_content;
-    let crate_details = cexpect!(CrateDetails::new(&conn, &name, &version));
     let (path, version) = if let Some(version) = latest_version(&crate_details.versions, &version) {
         req_path[2] = &version;
         (path_for_version(&req_path, &crate_details.target_name, &conn), version)

src/web/source.rs

@@ -93,7 +93,8 @@ impl FileList {
                                       releases.description,
                                       releases.target_name,
                                       releases.rustdoc_status,
-                                      releases.files
+                                      releases.files,
+                                      releases.default_target
                                FROM releases
                                LEFT OUTER JOIN crates ON crates.id = releases.crate_id
                                WHERE crates.name = $1 AND releases.version = $2",
@@ -173,6 +174,7 @@ impl FileList {
                 description: rows.get(0).get(2),
                 target_name: rows.get(0).get(3),
                 rustdoc_status: rows.get(0).get(4),
+                default_target: rows.get(0).get(5),
             },
             files: file_list,
         })