refactor(indexHandler): Don't retain configuration (#86)

Similar to the previous patch,
this patch removes knowledge of the configuration from the index handler.
Instead, the index handler is now passed a list of packageInfo structs
each containing just the information needed to render the index page.

This also obviates the need to duplicate the logic to compute
the package import path in the index.html template.

1 files changed, 25 insertions, 3 deletions

diff --git a/handler.go b/handler.go
index 5144caf..918405e 100644
--- a/handler.go
+++ b/handler.go
@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"html/template"
 	"net/http"
+	"sort"
 	"strings"
 
 	"go.uber.org/sally/templates"
@@ -20,20 +21,38 @@ var (
 func CreateHandler(config *Config) http.Handler {
 	mux := http.NewServeMux()
 
-	mux.Handle("/", &indexHandler{config: config})
+	pkgs := make([]packageInfo, 0, len(config.Packages))
 	for name, pkg := range config.Packages {
 		handler := newPackageHandler(config, name, pkg)
 		// Double-register so that "/foo"
 		// does not redirect to "/foo/" with a 300.
 		mux.Handle("/"+name, handler)
 		mux.Handle("/"+name+"/", handler)
+
+		pkgs = append(pkgs, packageInfo{
+			Desc:       pkg.Desc,
+			ImportPath: handler.canonicalURL,
+			GitURL:     handler.gitURL,
+			GodocHome:  handler.godocHost + "/" + handler.canonicalURL,
+		})
 	}
+	sort.Slice(pkgs, func(i, j int) bool {
+		return pkgs[i].ImportPath < pkgs[j].ImportPath
+	})
+	mux.Handle("/", &indexHandler{pkgs: pkgs})
 
 	return mux
 }
 
 type indexHandler struct {
-	config *Config
+	pkgs []packageInfo
+}
+
+type packageInfo struct {
+	Desc       string // package description
+	ImportPath string // canonical improt path
+	GitURL     string // URL of the Git repository
+	GodocHome  string // documentation home URL
 }
 
 func (h *indexHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
@@ -44,7 +63,10 @@ func (h *indexHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if err := indexTemplate.Execute(w, h.config); err != nil {
+	data := struct{ Packages []packageInfo }{
+		Packages: h.pkgs,
+	}
+	if err := indexTemplate.Execute(w, data); err != nil {
 		http.Error(w, err.Error(), 500)
 	}
 }