diff options
Diffstat (limited to 'modules/caddyhttp/rewrite/rewrite.go')
| -rw-r--r-- | modules/caddyhttp/rewrite/rewrite.go | 149 |
1 files changed, 99 insertions, 50 deletions
diff --git a/modules/caddyhttp/rewrite/rewrite.go b/modules/caddyhttp/rewrite/rewrite.go index f610658..a142080 100644 --- a/modules/caddyhttp/rewrite/rewrite.go +++ b/modules/caddyhttp/rewrite/rewrite.go @@ -35,8 +35,9 @@ type Rewrite struct { Method string `json:"method,omitempty"` URI string `json:"uri,omitempty"` - StripPathPrefix string `json:"strip_path_prefix,omitempty"` - StripPathSuffix string `json:"strip_path_suffix,omitempty"` + StripPathPrefix string `json:"strip_path_prefix,omitempty"` + StripPathSuffix string `json:"strip_path_suffix,omitempty"` + URISubstring []replacer `json:"uri_substring,omitempty"` HTTPRedirect caddyhttp.WeakString `json:"http_redirect,omitempty"` Rehandle bool `json:"rehandle,omitempty"` @@ -61,49 +62,76 @@ func (rewr *Rewrite) Provision(ctx caddy.Context) error { // Validate ensures rewr's configuration is valid. func (rewr Rewrite) Validate() error { if rewr.HTTPRedirect != "" && rewr.Rehandle { - return fmt.Errorf("cannot be configured to both write a redirect response and rehandle internally") + return fmt.Errorf("cannot be configured to both redirect externally and rehandle internally") } return nil } func (rewr Rewrite) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler) error { repl := r.Context().Value(caddy.ReplacerCtxKey).(caddy.Replacer) - var changed bool logger := rewr.logger.With( zap.Object("request", caddyhttp.LoggableHTTPRequest{Request: r}), ) - // rewrite the method + changed := rewr.rewrite(r, repl, logger) + + if changed { + logger.Debug("rewrote request", + zap.String("method", r.Method), + zap.String("uri", r.RequestURI), + ) + if rewr.Rehandle { + return caddyhttp.ErrRehandle + } + if rewr.HTTPRedirect != "" { + statusCode, err := strconv.Atoi(repl.ReplaceAll(rewr.HTTPRedirect.String(), "")) + if err != nil { + return caddyhttp.Error(http.StatusInternalServerError, err) + } + w.Header().Set("Location", r.RequestURI) + w.WriteHeader(statusCode) + return nil + } + } + + return next.ServeHTTP(w, r) +} + +// rewrite performs the rewrites on r using repl, which +// should have been obtained from r, but is passed in for +// efficiency. It returns true if any changes were made to r. +func (rewr Rewrite) rewrite(r *http.Request, repl caddy.Replacer, logger *zap.Logger) bool { + oldMethod := r.Method + oldURI := r.RequestURI + + // method if rewr.Method != "" { - method := r.Method r.Method = strings.ToUpper(repl.ReplaceAll(rewr.Method, "")) - if r.Method != method { - changed = true - } } - // rewrite the URI + // uri (which consists of path, query string, and maybe fragment?) if rewr.URI != "" { - oldURI := r.RequestURI newURI := repl.ReplaceAll(rewr.URI, "") - u, err := url.Parse(newURI) + newU, err := url.Parse(newURI) if err != nil { - return caddyhttp.Error(http.StatusInternalServerError, err) + logger.Error("parsing new URI", + zap.String("raw_input", rewr.URI), + zap.String("input", newURI), + zap.Error(err), + ) } - r.RequestURI = newURI - r.URL.Path = u.Path - if u.RawQuery != "" { - r.URL.RawQuery = u.RawQuery + if newU.Path != "" { + r.URL.Path = newU.Path } - if u.Fragment != "" { - r.URL.Fragment = u.Fragment + if newU.RawQuery != "" { + newU.RawQuery = strings.TrimPrefix(newU.RawQuery, "&") + r.URL.RawQuery = newU.RawQuery } - - if newURI != oldURI { - changed = true + if newU.Fragment != "" { + r.URL.Fragment = newU.Fragment } } @@ -111,42 +139,63 @@ func (rewr Rewrite) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddy if rewr.StripPathPrefix != "" { prefix := repl.ReplaceAll(rewr.StripPathPrefix, "") r.URL.Path = strings.TrimPrefix(r.URL.Path, prefix) - newURI := r.URL.String() - if newURI != r.RequestURI { - changed = true - } - r.RequestURI = newURI } if rewr.StripPathSuffix != "" { suffix := repl.ReplaceAll(rewr.StripPathSuffix, "") r.URL.Path = strings.TrimSuffix(r.URL.Path, suffix) - newURI := r.URL.String() - if newURI != r.RequestURI { - changed = true - } - r.RequestURI = newURI } - if changed { - logger.Debug("rewrote request", - zap.String("method", r.Method), - zap.String("uri", r.RequestURI), - ) - if rewr.Rehandle { - return caddyhttp.ErrRehandle - } - if rewr.HTTPRedirect != "" { - statusCode, err := strconv.Atoi(repl.ReplaceAll(rewr.HTTPRedirect.String(), "")) - if err != nil { - return caddyhttp.Error(http.StatusInternalServerError, err) - } - w.Header().Set("Location", r.RequestURI) - w.WriteHeader(statusCode) - return nil - } + // substring replacements in URI + for _, rep := range rewr.URISubstring { + rep.do(r, repl) } - return next.ServeHTTP(w, r) + // update the encoded copy of the URI + r.RequestURI = r.URL.RequestURI() + + // return true if anything changed + return r.Method != oldMethod || r.RequestURI != oldURI +} + +// replacer describes a simple and fast substring replacement. +type replacer struct { + // The substring to find. Supports placeholders. + Find string `json:"find,omitempty"` + + // The substring to replace. Supports placeholders. + Replace string `json:"replace,omitempty"` + + // Maximum number of replacements per string. + // Set to <= 0 for no limit (default). + Limit int `json:"limit,omitempty"` +} + +// do performs the replacement on r and returns true if any changes were made. +func (rep replacer) do(r *http.Request, repl caddy.Replacer) bool { + if rep.Find == "" || rep.Replace == "" { + return false + } + + lim := rep.Limit + if lim == 0 { + lim = -1 + } + + find := repl.ReplaceAll(rep.Find, "") + replace := repl.ReplaceAll(rep.Replace, "") + + oldPath := r.URL.Path + oldQuery := r.URL.RawQuery + + r.URL.Path = strings.Replace(oldPath, find, replace, lim) + r.URL.RawQuery = strings.Replace(oldQuery, find, replace, lim) + + // changed := r.URL.Path != oldPath && r.URL.RawQuery != oldQuery + // if changed { + // r.RequestURI = r.URL.RequestURI() + // } + + return r.URL.Path != oldPath && r.URL.RawQuery != oldQuery } // Interface guard |