Fast and extensible multi-platform HTTP/1-2-3 web server with automatic HTTPS
Mirrored from https://github.com/Slazee/caddy.git
Synced Nov 11, 01:00 UTC
| 1 | package network |
| 2 | |
| 3 | import ( |
| 4 | "errors" |
| 5 | "net/http" |
| 6 | "net/url" |
| 7 | "strings" |
| 8 | |
| 9 | "go.uber.org/zap" |
| 10 | |
| 11 | "github.com/caddyserver/caddy/v2" |
| 12 | "github.com/caddyserver/caddy/v2/caddyconfig/caddyfile" |
| 13 | ) |
| 14 | |
| 15 | func init() { |
| 16 | caddy.RegisterModule(ProxyFromURL{}) |
| 17 | caddy.RegisterModule(ProxyFromNone{}) |
| 18 | } |
| 19 | |
| 20 | // The "url" proxy source uses the defined URL as the proxy |
| 21 | type ProxyFromURL struct { |
| 22 | URL string `json:"url"` |
| 23 | |
| 24 | ctx caddy.Context |
| 25 | logger *zap.Logger |
| 26 | } |
| 27 | |
| 28 | // CaddyModule implements Module. |
| 29 | func (p ProxyFromURL) CaddyModule() caddy.ModuleInfo { |
| 30 | return caddy.ModuleInfo{ |
| 31 | ID: "caddy.network_proxy.url", |
| 32 | New: func() caddy.Module { |
| 33 | return &ProxyFromURL{} |
| 34 | }, |
| 35 | } |
| 36 | } |
| 37 | |
| 38 | func (p *ProxyFromURL) Provision(ctx caddy.Context) error { |
| 39 | p.ctx = ctx |
| 40 | p.logger = ctx.Logger() |
| 41 | return nil |
| 42 | } |
| 43 | |
| 44 | // Validate implements Validator. |
| 45 | func (p ProxyFromURL) Validate() error { |
| 46 | if _, err := url.Parse(p.URL); err != nil { |
| 47 | return err |
| 48 | } |
| 49 | return nil |
| 50 | } |
| 51 | |
| 52 | // ProxyFunc implements ProxyFuncProducer. |
| 53 | func (p ProxyFromURL) ProxyFunc() func(*http.Request) (*url.URL, error) { |
| 54 | if strings.Contains(p.URL, "{") && strings.Contains(p.URL, "}") { |
| 55 | // courtesy of @ImpostorKeanu: https://github.com/caddyserver/caddy/pull/6397 |
| 56 | return func(r *http.Request) (*url.URL, error) { |
| 57 | // retrieve the replacer from context. |
| 58 | repl, ok := r.Context().Value(caddy.ReplacerCtxKey).(*caddy.Replacer) |
| 59 | if !ok { |
| 60 | err := errors.New("failed to obtain replacer from request") |
| 61 | p.logger.Error(err.Error()) |
| 62 | return nil, err |
| 63 | } |
| 64 | |
| 65 | // apply placeholders to the value |
| 66 | // note: h.ForwardProxyURL should never be empty at this point |
| 67 | s := repl.ReplaceAll(p.URL, "") |
| 68 | if s == "" { |
| 69 | p.logger.Error("network_proxy URL was empty after applying placeholders", |
| 70 | zap.String("initial_value", p.URL), |
| 71 | zap.String("final_value", s), |
| 72 | zap.String("hint", "check for invalid placeholders")) |
| 73 | return nil, errors.New("empty value for network_proxy URL") |
| 74 | } |
| 75 | |
| 76 | // parse the url |
| 77 | pUrl, err := url.Parse(s) |
| 78 | if err != nil { |
| 79 | p.logger.Warn("failed to derive transport proxy from network_proxy URL") |
| 80 | pUrl = nil |
| 81 | } else if pUrl.Hostname() == "" { |
| 82 | // url.Parse does not return an error on these values: |
| 83 | // |
| 84 | // - http://:80 |
| 85 | // - pUrl.Host == ":80" |
| 86 | // - /some/path |
| 87 | // - pUrl.Host == "" |
| 88 | // |
| 89 | // Super edge cases, but humans are human. |
| 90 | err = errors.New("supplied network_proxy URL is missing a host value") |
| 91 | pUrl = nil |
| 92 | } else { |
| 93 | p.logger.Debug("setting transport proxy url", zap.String("url", s)) |
| 94 | } |
| 95 | |
| 96 | return pUrl, err |
| 97 | } |
| 98 | } |
| 99 | return func(r *http.Request) (*url.URL, error) { |
| 100 | return url.Parse(p.URL) |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | // UnmarshalCaddyfile implements caddyfile.Unmarshaler. |
| 105 | func (p *ProxyFromURL) UnmarshalCaddyfile(d *caddyfile.Dispenser) error { |
| 106 | d.Next() |
| 107 | d.Next() |
| 108 | p.URL = d.Val() |
| 109 | return nil |
| 110 | } |
| 111 | |
| 112 | // The "none" proxy source module disables the use of network proxy. |
| 113 | type ProxyFromNone struct{} |
| 114 | |
| 115 | func (p ProxyFromNone) CaddyModule() caddy.ModuleInfo { |
| 116 | return caddy.ModuleInfo{ |
| 117 | ID: "caddy.network_proxy.none", |
| 118 | New: func() caddy.Module { |
| 119 | return &ProxyFromNone{} |
| 120 | }, |
| 121 | } |
| 122 | } |
| 123 | |
| 124 | // UnmarshalCaddyfile implements caddyfile.Unmarshaler. |
| 125 | func (p ProxyFromNone) UnmarshalCaddyfile(d *caddyfile.Dispenser) error { |
| 126 | return nil |
| 127 | } |
| 128 | |
| 129 | // ProxyFunc implements ProxyFuncProducer. |
| 130 | func (p ProxyFromNone) ProxyFunc() func(*http.Request) (*url.URL, error) { |
| 131 | return nil |
| 132 | } |
| 133 | |
| 134 | var ( |
| 135 | _ caddy.Module = ProxyFromURL{} |
| 136 | _ caddy.Provisioner = (*ProxyFromURL)(nil) |
| 137 | _ caddy.Validator = ProxyFromURL{} |
| 138 | _ caddy.ProxyFuncProducer = ProxyFromURL{} |
| 139 | _ caddyfile.Unmarshaler = (*ProxyFromURL)(nil) |
| 140 | |
| 141 | _ caddy.Module = ProxyFromNone{} |
| 142 | _ caddy.ProxyFuncProducer = ProxyFromNone{} |
| 143 | _ caddyfile.Unmarshaler = ProxyFromNone{} |
| 144 | ) |