aboutsummaryrefslogtreecommitdiff
path: root/handler.go
blob: aa646c642dd70d07b03ec918ea184df1aace0670 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
package main

import (
	"fmt"
	"html/template"
	"net/http"
	"sort"
	"strings"

	"go.uber.org/sally/templates"
)

var (
	indexTemplate = template.Must(
		template.New("index.html").Parse(templates.Index))
	packageTemplate = template.Must(
		template.New("package.html").Parse(templates.Package))
)

// CreateHandler creates a Sally http.Handler
func CreateHandler(config *Config) http.Handler {
	mux := http.NewServeMux()

	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 {
	pkgs []packageInfo
}

type packageInfo struct {
	Desc       string // package description
	ImportPath string // canonical import path
	GitURL     string // URL of the Git repository
	GodocHome  string // documentation home URL
}

func (h *indexHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	// Index handler only supports '/'.
	// ServeMux will call us for any '/foo' that is not a known package.
	if r.Method != http.MethodGet || r.URL.Path != "/" {
		http.NotFound(w, r)
		return
	}

	data := struct{ Packages []packageInfo }{
		Packages: h.pkgs,
	}
	if err := indexTemplate.Execute(w, data); err != nil {
		http.Error(w, err.Error(), 500)
	}
}

type packageHandler struct {
	// Hostname of the godoc server, e.g. "godoc.org".
	godocHost string

	// Name of the package relative to the vanity base URL.
	// For example, "zap" for "go.uber.org/zap".
	name string

	// Path at which the Git repository is hosted.
	// For example, "github.com/uber-go/zap".
	gitURL string

	// Default branch of the Git repository.
	defaultBranch string

	// Canonical import path for the package.
	canonicalURL string
}

func newPackageHandler(cfg *Config, name string, pkg PackageConfig) *packageHandler {
	baseURL := cfg.URL
	if pkg.URL != "" {
		baseURL = pkg.URL
	}
	canonicalURL := fmt.Sprintf("%s/%s", baseURL, name)

	return &packageHandler{
		godocHost:     cfg.Godoc.Host,
		name:          name,
		canonicalURL:  canonicalURL,
		gitURL:        pkg.Repo,
		defaultBranch: pkg.Branch,
	}
}

func (h *packageHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet {
		http.NotFound(w, r)
		return
	}

	// Extract the relative path to subpackages, if any.
	//	"/foo/bar" => "/bar"
	//	"/foo" => ""
	relPath := strings.TrimPrefix(r.URL.Path, "/"+h.name)

	data := struct {
		Repo         string
		CanonicalURL string
		GodocURL     string
	}{
		Repo:         h.gitURL,
		CanonicalURL: h.canonicalURL,
		GodocURL:     fmt.Sprintf("https://%s/%s%s", h.godocHost, h.canonicalURL, relPath),
	}
	if err := packageTemplate.Execute(w, data); err != nil {
		http.Error(w, err.Error(), 500)
	}
}