Implement most of static file server; refactor and improve Replacer

1 files changed, 64 insertions, 100 deletions

diff --git a/modules/caddyhttp/replacer.go b/modules/caddyhttp/replacer.go
index e7aa250..6feb143 100644
--- a/modules/caddyhttp/replacer.go
+++ b/modules/caddyhttp/replacer.go
@@ -1,119 +1,83 @@
 package caddyhttp
 
 import (
+	"fmt"
 	"net"
 	"net/http"
-	"os"
+	"path"
 	"strings"
 
 	"bitbucket.org/lightcodelabs/caddy2"
 )
 
-// Replacer can replace values in strings based
-// on a request and/or response writer. The zero
-// Replacer is not valid; use NewReplacer() to
-// initialize one.
-type Replacer struct {
-	req    *http.Request
-	resp   http.ResponseWriter
-	custom map[string]string
-}
-
-// NewReplacer makes a new Replacer, initializing all necessary
-// fields. The request and response writer are optional, but
-// necessary for most replacements to work.
-func NewReplacer(req *http.Request, rw http.ResponseWriter) *Replacer {
-	return &Replacer{
-		req:    req,
-		resp:   rw,
-		custom: make(map[string]string),
-	}
-}
-
-// Map sets a custom variable mapping to a value.
-func (r *Replacer) Map(variable, value string) {
-	r.custom[variable] = value
-}
-
-// Replace replaces placeholders in input with the value. If
-// the value is empty string, the placeholder is substituted
-// with the value empty.
-func (r *Replacer) Replace(input, empty string) string {
-	if !strings.Contains(input, phOpen) {
-		return input
-	}
-
-	input = r.replaceAll(input, empty, r.defaults())
-	input = r.replaceAll(input, empty, r.custom)
-
-	return input
-}
-
-func (r *Replacer) replaceAll(input, empty string, mapping map[string]string) string {
-	for key, val := range mapping {
-		if val == "" {
-			val = empty
-		}
-		input = strings.ReplaceAll(input, phOpen+key+phClose, val)
-	}
-	return input
-}
-
-func (r *Replacer) defaults() map[string]string {
-	m := map[string]string{
-		"system.hostname": func() string {
-			// OK if there is an error; just return empty string
-			name, _ := os.Hostname()
-			return name
-		}(),
-	}
-
-	if r.req != nil {
-		m["request.host"] = func() string {
-			host, _, err := net.SplitHostPort(r.req.Host)
-			if err != nil {
-				return r.req.Host // OK; there probably was no port
+// TODO: A simple way to format or escape or encode each value would be nice
+// ... TODO: Should we just use templates? :-/ yeesh...
+
+func newReplacer(req *http.Request, w http.ResponseWriter) caddy2.Replacer {
+	repl := caddy2.NewReplacer()
+
+	httpVars := func() map[string]string {
+		m := make(map[string]string)
+		if req != nil {
+			m["http.request.host"] = func() string {
+				host, _, err := net.SplitHostPort(req.Host)
+				if err != nil {
+					return req.Host // OK; there probably was no port
+				}
+				return host
+			}()
+			m["http.request.hostport"] = req.Host // may include both host and port
+			m["http.request.method"] = req.Method
+			m["http.request.port"] = func() string {
+				// if there is no port, there will be an error; in
+				// that case, port is the empty string anyway
+				_, port, _ := net.SplitHostPort(req.Host)
+				return port
+			}()
+			m["http.request.scheme"] = func() string {
+				if req.TLS != nil {
+					return "https"
+				}
+				return "http"
+			}()
+			m["http.request.uri"] = req.URL.RequestURI()
+			m["http.request.uri.path"] = req.URL.Path
+			m["http.request.uri.path.file"] = func() string {
+				_, file := path.Split(req.URL.Path)
+				return file
+			}()
+			m["http.request.uri.path.dir"] = func() string {
+				dir, _ := path.Split(req.URL.Path)
+				return dir
+			}()
+
+			for field, vals := range req.Header {
+				m["http.request.header."+strings.ToLower(field)] = strings.Join(vals, ",")
 			}
-			return host
-		}()
-		m["request.hostport"] = r.req.Host // may include both host and port
-		m["request.method"] = r.req.Method
-		m["request.port"] = func() string {
-			// if there is no port, there will be an error; in
-			// that case, port is the empty string anyway
-			_, port, _ := net.SplitHostPort(r.req.Host)
-			return port
-		}()
-		m["request.scheme"] = func() string {
-			if r.req.TLS != nil {
-				return "https"
+			for _, cookie := range req.Cookies() {
+				m["http.request.cookie."+cookie.Name] = cookie.Value
+			}
+			for param, vals := range req.URL.Query() {
+				m["http.request.uri.query."+param] = strings.Join(vals, ",")
 			}
-			return "http"
-		}()
-		m["request.uri"] = r.req.URL.RequestURI()
-		m["request.uri.path"] = r.req.URL.Path
 
-		for field, vals := range r.req.Header {
-			m["request.header."+strings.ToLower(field)] = strings.Join(vals, ",")
-		}
-		for _, cookie := range r.req.Cookies() {
-			m["request.cookie."+cookie.Name] = cookie.Value
-		}
-		for param, vals := range r.req.URL.Query() {
-			m["request.uri.query."+param] = strings.Join(vals, ",")
+			hostLabels := strings.Split(req.Host, ".")
+			for i, label := range hostLabels {
+				key := fmt.Sprintf("http.request.host.labels.%d", len(hostLabels)-i-1)
+				m[key] = label
+			}
 		}
-	}
 
-	if r.resp != nil {
-		for field, vals := range r.resp.Header() {
-			m["response.header."+strings.ToLower(field)] = strings.Join(vals, ",")
+		if w != nil {
+			for field, vals := range w.Header() {
+				m["http.response.header."+strings.ToLower(field)] = strings.Join(vals, ",")
+			}
 		}
-	}
 
-	return m
-}
+		return m
+	}
 
-const phOpen, phClose = "{", "}"
+	repl.Map(httpVars)
 
-// ReplacerCtxKey is the context key for the request's replacer.
-const ReplacerCtxKey caddy2.CtxKey = "replacer"
+	return repl
+}