generalizing fastcgi parameters, and improving headers passed.

middleware/fastcgi/fastcgi.go

@@ -4,6 +4,8 @@
 package fastcgi
 
 import (
+	"errors"
+	"fmt"
 	"io"
 	"io/ioutil"
 	"net/http"
@@ -17,7 +19,10 @@ import (
 
 // New generates a new FastCGI middleware.
 func New(c middleware.Controller) (middleware.Middleware, error) {
-	root := c.Root()
+	root, err := filepath.Abs(c.Root())
+	if err != nil {
+		return nil, err
+	}
 
 	rules, err := parse(c)
 	if err != nil {
@@ -25,130 +30,180 @@ func New(c middleware.Controller) (middleware.Middleware, error) {
 	}
 
 	return func(next middleware.Handler) middleware.Handler {
-		return Handler{Next: next, Rules: rules, Root: root}
+		return Handler{
+			Next:            next,
+			Rules:           rules,
+			Root:            root,
+			SoftwareName:    "Caddy", // TODO: Once generators are not in the same pkg as handler, obtain this from some global const
+			SoftwareVersion: "",      // TODO: Get this from some global const too
+			// TODO: Set ServerName and ServerPort to correct values... (as user defined in config)
+		}
 	}, nil
 }
 
 // Handler is a middleware type that can handle requests as a FastCGI client.
 type Handler struct {
 	Next  middleware.Handler
-	Root  string
+	Root  string // must be absolute path to site root
 	Rules []Rule
-}
 
-func (h Handler) DoesFileExist(path string) bool {
-	file := h.Root + path
-	if _, err := os.Stat(file); err == nil {
-		return true
-	}
-	return false
+	// These are sent to CGI scripts in env variables
+	SoftwareName    string
+	SoftwareVersion string
+	ServerName      string
+	ServerPort      string
 }
 
 // ServeHTTP satisfies the middleware.Handler interface.
 func (h Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) (int, error) {
-	servedFcgi := false
-	indexFile := "index.php"
-	ext := ".php"
-	splitText := ".php"
 	for _, rule := range h.Rules {
-		if middleware.Path(r.URL.Path).Matches(rule.Path) && (strings.HasSuffix(r.URL.Path, "/") ||
-			strings.HasSuffix(r.URL.Path, ext) || !h.DoesFileExist(r.URL.Path)) {
+		// In addition to matching the path, a request must meet some
+		// other criteria before being proxied as FastCGI. For example,
+		// we probably want to exclude static assets (CSS, JS, images...)
+		// but we also want to be flexible for the script we proxy to.
 
-			// Get absolute file paths
-			absPath, err := filepath.Abs(h.Root + r.URL.Path)
-			if err != nil {
-				return http.StatusInternalServerError, err
-			}
+		// These criteria work well in this order for PHP sites
+		if middleware.Path(r.URL.Path).Matches(rule.Path) &&
+			(r.URL.Path[len(r.URL.Path)-1] == '/' ||
+				strings.HasSuffix(r.URL.Path, rule.Ext) ||
+				!h.exists(r.URL.Path)) {
 
-			// Get absolute file path to website root
-			absRootPath, err := filepath.Abs(h.Root)
+			// Create environment for CGI script
+			env, err := h.buildEnv(r, rule)
 			if err != nil {
 				return http.StatusInternalServerError, err
 			}
 
-			// Separate remote IP and port
-			var ip, port string
-			if idx := strings.Index(r.RemoteAddr, ":"); idx > -1 {
-				ip = r.RemoteAddr[:idx]
-				port = r.RemoteAddr[idx:]
-			} else {
-				ip = r.RemoteAddr
-			}
-
-			// TODO: Do we really have to make this map from scratch for each request?
-			// TODO: We have quite a few more to map, too.
-			env := make(map[string]string)
-			env["SERVER_NAME"] = "caddy"
-			env["SERVER_SOFTWARE"] = "caddy" // TODO: Obtain version info...
-			env["SERVER_PROTOCOL"] = r.Proto
-			env["SCRIPT_FILENAME"] = absPath
-			env["REMOTE_ADDR"] = ip
-			env["REMOTE_PORT"] = port
-			env["REQUEST_METHOD"] = r.Method
-			env["QUERY_STRING"] = r.URL.RawQuery
-			env["SCRIPT_NAME"] = r.URL.Path
-			env["HTTP_HOST"] = r.Host
-
-			split := strings.Index(r.URL.Path, splitText)
-
-			if split == -1 {
-				//request doesn't have the extension
-				//send the request to the index file
-				env["DOCUMENT_URI"] = "/" + indexFile
-				env["SCRIPT_NAME"] = "/" + indexFile
-				env["SCRIPT_FILENAME"] = absRootPath + "/" + indexFile
-				env["PATH_INFO"] = r.URL.Path
-			} else {
-				env["DOCUMENT_URI"] = r.URL.Path[:split+len(splitText)]
-				env["PATH_INFO"] = r.URL.Path[split+len(splitText):]
-			}
-
-			env["REQUEST_URI"] = r.URL.RequestURI()
-
-			env["DOCUMENT_ROOT"] = absRootPath
-			env["HTTP_COOKIE"] = r.Header.Get("Cookie")
-
+			// Connect to FastCGI gateway
 			fcgi, err := Dial("tcp", rule.Address)
 			if err != nil {
 				return http.StatusBadGateway, err
 			}
 
+			// TODO: Allow more methods (requires refactoring fcgiclient first...)
 			var resp *http.Response
-			if r.Method == "GET" {
+			switch r.Method {
+			case "GET":
 				resp, err = fcgi.Get(env)
-			} else {
+			case "POST":
 				l, _ := strconv.Atoi(r.Header.Get("Content-Length"))
 				resp, err = fcgi.Post(env, r.Header.Get("Content-Type"), r.Body, l)
+			default:
+				return http.StatusMethodNotAllowed, nil
 			}
-			if err != nil && err != io.EOF {
-				return http.StatusBadGateway, err
-			}
+			defer resp.Body.Close()
 
-			body, err := ioutil.ReadAll(resp.Body)
-			if err != nil {
+			if err != nil && err != io.EOF {
 				return http.StatusBadGateway, err
 			}
 
+			// Write the response header
 			for key, vals := range resp.Header {
 				for _, val := range vals {
 					w.Header().Add(key, val)
 				}
 			}
-
 			w.WriteHeader(resp.StatusCode)
-			w.Write(body)
 
-			servedFcgi = true
+			body, err := ioutil.ReadAll(resp.Body)
+			fmt.Printf("%s", body)
+			fmt.Printf("%d\n", resp.StatusCode)
+			fmt.Printf("%d\n", len(body))
+			w.Write(body)
 
 			return resp.StatusCode, nil
 		}
 	}
 
-	if !servedFcgi {
-		return h.Next.ServeHTTP(w, r)
+	return h.Next.ServeHTTP(w, r)
+}
+
+func (h Handler) exists(path string) bool {
+	if _, err := os.Stat(h.Root + path); err == nil {
+		return true
+	}
+	return false
+}
+
+func (h Handler) buildEnv(r *http.Request, rule Rule) (map[string]string, error) {
+	var env map[string]string
+
+	// Get absolute path of requested resource
+	absPath, err := filepath.Abs(h.Root + r.URL.Path)
+	if err != nil {
+		return env, err
+	}
+
+	// Separate remote IP and port; more lenient than net.SplitHostPort
+	var ip, port string
+	if idx := strings.Index(r.RemoteAddr, ":"); idx > -1 {
+		ip = r.RemoteAddr[:idx]
+		port = r.RemoteAddr[idx+1:]
+	} else {
+		ip = r.RemoteAddr
 	}
 
-	return 0, nil
+	// Split path in preparation for env variables
+	splitPos := strings.Index(r.URL.Path, rule.SplitPath)
+	var docURI, scriptName, scriptFilename, pathInfo string
+	if splitPos == -1 {
+		// Request doesn't have the extension, so assume index file
+		docURI = "/" + rule.IndexFile
+		scriptName = "/" + rule.IndexFile
+		scriptFilename = h.Root + "/" + rule.IndexFile
+		pathInfo = r.URL.Path
+	} else {
+		// Request has the extension; path was split successfully
+		docURI = r.URL.Path[:splitPos+len(rule.SplitPath)]
+		pathInfo = r.URL.Path[splitPos+len(rule.SplitPath):]
+		scriptName = r.URL.Path
+		scriptFilename = absPath
+	}
+
+	// Some variables are unused but cleared explicitly to prevent
+	// the parent environment from interfering.
+	env = map[string]string{
+
+		// Variables defined in CGI 1.1 spec
+		"AUTH_TYPE":         "", // Not used
+		"CONTENT_LENGTH":    r.Header.Get("Content-Length"),
+		"CONTENT_TYPE":      r.Header.Get("Content-Type"),
+		"GATEWAY_INTERFACE": "CGI/1.1",
+		"PATH_INFO":         pathInfo,
+		"PATH_TRANSLATED":   h.Root + "/" + pathInfo, // Source for path_translated: http://www.oreilly.com/openbook/cgi/ch02_04.html
+		"QUERY_STRING":      r.URL.RawQuery,
+		"REMOTE_ADDR":       ip,
+		"REMOTE_HOST":       ip, // For speed, remote host lookups disabled
+		"REMOTE_PORT":       port,
+		"REMOTE_IDENT":      "", // Not used
+		"REMOTE_USER":       "", // Not used
+		"REQUEST_METHOD":    r.Method,
+		"SERVER_NAME":       h.ServerName,
+		"SERVER_PORT":       h.ServerPort,
+		"SERVER_PROTOCOL":   r.Proto,
+		"SERVER_SOFTWARE":   h.SoftwareName + "/" + h.SoftwareVersion,
+
+		// Other variables
+		"DOCUMENT_ROOT":   h.Root,
+		"DOCUMENT_URI":    docURI,
+		"HTTP_HOST":       r.Host, // added here, since not always part of headers
+		"REQUEST_URI":     r.URL.RequestURI(),
+		"SCRIPT_FILENAME": scriptFilename,
+		"SCRIPT_NAME":     scriptName,
+	}
+
+	// Add all HTTP headers to env variables
+	for field, val := range r.Header {
+		header := strings.ToUpper(field)
+		header = headerNameReplacer.Replace(header)
+		// We don't want to pass the encoding header to prevent the fastcgi server from gzipping
+		// TODO: is there a better way.
+		if header != "ACCEPT_ENCODING" {
+			env["HTTP_"+header] = strings.Join(val, ", ")
+		}
+	}
+
+	return env, nil
 }
 
 func parse(c middleware.Controller) ([]Rule, error) {
@@ -156,16 +211,86 @@ func parse(c middleware.Controller) ([]Rule, error) {
 
 	for c.Next() {
 		var rule Rule
-		if !c.Args(&rule.Path, &rule.Address) {
+
+		args := c.RemainingArgs()
+
+		switch len(args) {
+		case 0:
 			return rules, c.ArgErr()
+		case 1:
+			rule.Path = "/"
+			rule.Address = args[0]
+		case 2:
+			rule.Path = args[0]
+			rule.Address = args[1]
+		case 3:
+			rule.Path = args[0]
+			rule.Address = args[1]
+			err := preset(args[2], &rule)
+			if err != nil {
+				return rules, c.Err("Invalid fastcgi rule preset '" + args[2] + "'")
+			}
+		}
+
+		for c.NextBlock() {
+			switch c.Val() {
+			case "ext":
+				if !c.NextArg() {
+					return rules, c.ArgErr()
+				}
+				rule.Ext = c.Val()
+			case "split":
+				if !c.NextArg() {
+					return rules, c.ArgErr()
+				}
+				rule.SplitPath = c.Val()
+			case "index":
+				if !c.NextArg() {
+					return rules, c.ArgErr()
+				}
+				rule.IndexFile = c.Val()
+			}
 		}
+
 		rules = append(rules, rule)
 	}
 
 	return rules, nil
 }
 
+// preset configures rule according to name. It returns an error if
+// name is not a recognized preset name.
+func preset(name string, rule *Rule) error {
+	switch name {
+	case "php":
+		rule.Ext = ".php"
+		rule.SplitPath = ".php"
+		rule.IndexFile = "index.php"
+	default:
+		return errors.New(name + " is not a valid preset name")
+	}
+	return nil
+}
+
 // Rule represents a FastCGI handling rule.
 type Rule struct {
-	Path, Address string
+	// The base path to match. Required.
+	Path string
+
+	// The address of the FastCGI server. Required.
+	Address string
+
+	// Always process files with this extension with fastcgi.
+	Ext string
+
+	// The path in the URL will be split into two, with the first piece ending
+	// with the value of SplitPath. The first piece will be assumed as the
+	// actual resource (CGI script) name, and the second piece will be set to
+	// PATH_INFO for the CGI script to use.
+	SplitPath string
+
+	// If the URL does not indicate a file, an index file with this name will be assumed.
+	IndexFile string
 }
+
+var headerNameReplacer = strings.NewReplacer(" ", "_", "-", "_")

middleware/fastcgi/fcgiclient.go

@@ -376,10 +376,13 @@ func (this *FCGIClient) Request(p map[string]string, req io.Reader) (resp *http.
 
 	if resp.Header.Get("Status") != "" {
 		statusParts := strings.SplitN(resp.Header.Get("Status"), " ", 2)
-		resp.StatusCode, _ = strconv.Atoi(statusParts[0])
+		resp.StatusCode, err = strconv.Atoi(statusParts[0])
+		if err != nil {
+			return
+		}
 		resp.Status = statusParts[1]
 	} else {
-		resp.StatusCode = 200
+		resp.StatusCode = http.StatusOK
 	}
 
 	// TODO: fixTransferEncoding ?