Begin implementing error handling and re-handling

1 files changed, 106 insertions, 0 deletions

diff --git a/modules/caddyhttp/routes.go b/modules/caddyhttp/routes.go
new file mode 100644
index 0000000..95b6ee8
--- /dev/null
+++ b/modules/caddyhttp/routes.go
@@ -0,0 +1,106 @@
+package caddyhttp
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"bitbucket.org/lightcodelabs/caddy2"
+)
+
+type serverRoute struct {
+	Matchers map[string]json.RawMessage `json:"match"`
+	Apply    []json.RawMessage          `json:"apply"`
+	Respond  json.RawMessage            `json:"respond"`
+
+	Exclusive bool `json:"exclusive"`
+
+	// decoded values
+	matchers   []RouteMatcher
+	middleware []MiddlewareHandler
+	responder  Handler
+}
+
+type routeList []serverRoute
+
+func (routes routeList) buildMiddlewareChain(w http.ResponseWriter, r *http.Request) Handler {
+	if len(routes) == 0 {
+		return emptyHandler
+	}
+
+	var mid []Middleware
+	var responder Handler
+	mrw := &middlewareResponseWriter{ResponseWriterWrapper: &ResponseWriterWrapper{w}}
+
+	for _, route := range routes {
+		matched := len(route.matchers) == 0
+		for _, m := range route.matchers {
+			if m.Match(r) {
+				matched = true
+				break
+			}
+		}
+		if !matched {
+			continue
+		}
+		for _, m := range route.middleware {
+			mid = append(mid, func(next HandlerFunc) HandlerFunc {
+				return func(w http.ResponseWriter, r *http.Request) error {
+					return m.ServeHTTP(mrw, r, next)
+				}
+			})
+		}
+		if responder == nil {
+			responder = route.responder
+		}
+		if route.Exclusive {
+			break
+		}
+	}
+
+	// build the middleware stack, with the responder at the end
+	stack := HandlerFunc(func(w http.ResponseWriter, r *http.Request) error {
+		if responder == nil {
+			return nil
+		}
+		mrw.allowWrites = true
+		return responder.ServeHTTP(w, r)
+	})
+	for i := len(mid) - 1; i >= 0; i-- {
+		stack = mid[i](stack)
+	}
+
+	return stack
+}
+
+func (routes routeList) setup() error {
+	for i, route := range routes {
+		// matchers
+		for modName, rawMsg := range route.Matchers {
+			val, err := caddy2.LoadModule("http.matchers."+modName, rawMsg)
+			if err != nil {
+				return fmt.Errorf("loading matcher module '%s': %v", modName, err)
+			}
+			routes[i].matchers = append(routes[i].matchers, val.(RouteMatcher))
+		}
+
+		// middleware
+		for j, rawMsg := range route.Apply {
+			mid, err := caddy2.LoadModuleInlineName("http.middleware", rawMsg)
+			if err != nil {
+				return fmt.Errorf("loading middleware module in position %d: %v", j, err)
+			}
+			routes[i].middleware = append(routes[i].middleware, mid.(MiddlewareHandler))
+		}
+
+		// responder
+		if route.Respond != nil {
+			resp, err := caddy2.LoadModuleInlineName("http.responders", route.Respond)
+			if err != nil {
+				return fmt.Errorf("loading responder module: %v", err)
+			}
+			routes[i].responder = resp.(Handler)
+		}
+	}
+	return nil
+}