moved ysv -> vain

vain.go

@@ -0,0 +1,66 @@
+/*
+
+From the documentation for the go tool, it searches for the following header
+when searching for packages:
+
+<meta name="go-import" content="import-prefix vcs repo-root">
+
+this is simply a service for aggregating a collection of prefix, vcs, and
+repo-root tuples, and serving the appropriate header over http.
+
+API
+
+In order to add a new package POST a json object to the following route:
+
+POST /v0/package/
+
+A sample json object:
+
+	{
+		"path": "mcquay.me/vain",
+		"repo": "https://s.mcquay.me/sm/vain"
+	}
+
+Naming
+
+the "ysv" in ysvd stands for You're so Vain, the song by Carly Simon.
+*/
+package vain
+
+import "fmt"
+
+type vcs int
+
+const (
+	Git vcs = iota
+	Hg
+)
+
+var vcss = [...]string{
+	"git",
+	"mercurial",
+}
+
+var labelToVcs = map[string]vcs{
+	"git":       Git,
+	"mercurial": Hg,
+	"hg":        Hg,
+}
+
+// String returns the name of the vcs ("git", "mercurial", ...).
+func (v vcs) String() string { return vcss[v] }
+
+type Package struct {
+	Vcs  vcs    `json":vcs"`
+	Path string `json:"path"`
+	Repo string `json:"repo"`
+}
+
+func (p Package) String() string {
+	return fmt.Sprintf(
+		"<meta name=\"go-import\" content=\"%s %s %s\">",
+		p.Path,
+		p.Vcs,
+		p.Repo,
+	)
+}