use go 1.12

Signed-off-by: hongming <talonwan@yunify.com>

vendor/github.com/mholt/caddy/caddyhttp/push/setup.go

@@ -0,0 +1,193 @@
+// Copyright 2015 Light Code Labs, LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package push
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"strings"
+
+	"github.com/mholt/caddy"
+	"github.com/mholt/caddy/caddyhttp/httpserver"
+)
+
+func init() {
+	caddy.RegisterPlugin("push", caddy.Plugin{
+		ServerType: "http",
+		Action:     setup,
+	})
+}
+
+var errInvalidHeader = errors.New("header directive requires [name] [value]")
+
+var errHeaderStartsWithColon = errors.New("header cannot start with colon")
+var errMethodNotSupported = errors.New("push supports only GET and HEAD methods")
+
+const pushHeader = "X-Push"
+
+var emptyRules = []Rule{}
+
+// setup configures a new Push middleware
+func setup(c *caddy.Controller) error {
+	rules, err := parsePushRules(c)
+
+	if err != nil {
+		return err
+	}
+
+	cfg := httpserver.GetConfig(c)
+	cfg.AddMiddleware(func(next httpserver.Handler) httpserver.Handler {
+		return Middleware{Next: next, Rules: rules, Root: http.Dir(cfg.Root), indexPages: cfg.IndexPages}
+	})
+
+	return nil
+}
+
+func parsePushRules(c *caddy.Controller) ([]Rule, error) {
+	var rules = make(map[string]*Rule)
+
+	for c.NextLine() {
+		var rule *Rule
+		var resources []Resource
+		var ops []ruleOp
+
+		parseBlock := func() error {
+			for c.NextBlock() {
+				val := c.Val()
+
+				switch val {
+				case "method":
+					if !c.NextArg() {
+						return c.ArgErr()
+					}
+
+					method := c.Val()
+
+					if err := validateMethod(method); err != nil {
+						return errMethodNotSupported
+					}
+
+					ops = append(ops, setMethodOp(method))
+
+				case "header":
+					args := c.RemainingArgs()
+
+					if len(args) != 2 {
+						return errInvalidHeader
+					}
+
+					if err := validateHeader(args[0]); err != nil {
+						return err
+					}
+
+					ops = append(ops, setHeaderOp(args[0], args[1]))
+				default:
+					resources = append(resources, Resource{
+						Path:   val,
+						Method: http.MethodGet,
+						Header: http.Header{pushHeader: []string{}},
+					})
+				}
+			}
+			return nil
+		}
+
+		args := c.RemainingArgs()
+
+		if len(args) == 0 {
+			rule = new(Rule)
+			rule.Path = "/"
+			rules["/"] = rule
+			err := parseBlock()
+			if err != nil {
+				return emptyRules, err
+			}
+		} else {
+			path := args[0]
+
+			if existingRule, ok := rules[path]; ok {
+				rule = existingRule
+			} else {
+				rule = new(Rule)
+				rule.Path = path
+				rules[rule.Path] = rule
+			}
+
+			for i := 1; i < len(args); i++ {
+				resources = append(resources, Resource{
+					Path:   args[i],
+					Method: http.MethodGet,
+					Header: http.Header{pushHeader: []string{}},
+				})
+			}
+
+			err := parseBlock()
+			if err != nil {
+				return emptyRules, err
+			}
+		}
+
+		for _, op := range ops {
+			op(resources)
+		}
+		rule.Resources = append(rule.Resources, resources...)
+	}
+
+	var returnRules []Rule
+	for _, rule := range rules {
+		returnRules = append(returnRules, *rule)
+	}
+
+	return returnRules, nil
+}
+
+func setHeaderOp(key, value string) func(resources []Resource) {
+	return func(resources []Resource) {
+		for index := range resources {
+			resources[index].Header.Set(key, value)
+		}
+	}
+}
+
+func setMethodOp(method string) func(resources []Resource) {
+	return func(resources []Resource) {
+		for index := range resources {
+			resources[index].Method = method
+		}
+	}
+}
+
+func validateHeader(header string) error {
+	if strings.HasPrefix(header, ":") {
+		return errHeaderStartsWithColon
+	}
+
+	switch strings.ToLower(header) {
+	case "content-length", "content-encoding", "trailer", "te", "expect", "host":
+		return fmt.Errorf("push headers cannot include %s", header)
+	}
+
+	return nil
+}
+
+// rules based on https://go-review.googlesource.com/#/c/29439/4/http2/go18.go#94
+func validateMethod(method string) error {
+	if method != http.MethodGet && method != http.MethodHead {
+		return errMethodNotSupported
+	}
+
+	return nil
+}