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 | // Copyright 2015 Matthew Holt and The Caddy Authors |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | // you may not use this file except in compliance with the License. |
| 5 | // You may obtain a copy of the License at |
| 6 | // |
| 7 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | // See the License for the specific language governing permissions and |
| 13 | // limitations under the License. |
| 14 | |
| 15 | package caddyhttp |
| 16 | |
| 17 | import ( |
| 18 | "errors" |
| 19 | "fmt" |
| 20 | weakrand "math/rand/v2" |
| 21 | "path" |
| 22 | "runtime" |
| 23 | "strings" |
| 24 | |
| 25 | "github.com/caddyserver/caddy/v2" |
| 26 | ) |
| 27 | |
| 28 | // Error is a convenient way for a Handler to populate the |
| 29 | // essential fields of a HandlerError. If err is itself a |
| 30 | // HandlerError, then any essential fields that are not |
| 31 | // set will be populated. |
| 32 | func Error(statusCode int, err error) HandlerError { |
| 33 | const idLen = 9 |
| 34 | if he, ok := errors.AsType[HandlerError](err); ok { |
| 35 | if he.ID == "" { |
| 36 | he.ID = randString(idLen, true) |
| 37 | } |
| 38 | if he.Trace == "" { |
| 39 | he.Trace = trace() |
| 40 | } |
| 41 | if he.StatusCode == 0 { |
| 42 | he.StatusCode = statusCode |
| 43 | } |
| 44 | return he |
| 45 | } |
| 46 | return HandlerError{ |
| 47 | ID: randString(idLen, true), |
| 48 | StatusCode: statusCode, |
| 49 | Err: err, |
| 50 | Trace: trace(), |
| 51 | } |
| 52 | } |
| 53 | |
| 54 | // HandlerError is a serializable representation of |
| 55 | // an error from within an HTTP handler. |
| 56 | type HandlerError struct { |
| 57 | Err error // the original error value and message |
| 58 | StatusCode int // the HTTP status code to associate with this error |
| 59 | |
| 60 | ID string // generated; for identifying this error in logs |
| 61 | Trace string // produced from call stack |
| 62 | } |
| 63 | |
| 64 | func (e HandlerError) Error() string { |
| 65 | var s string |
| 66 | if e.ID != "" { |
| 67 | s += fmt.Sprintf("{id=%s}", e.ID) |
| 68 | } |
| 69 | if e.Trace != "" { |
| 70 | s += " " + e.Trace |
| 71 | } |
| 72 | if e.StatusCode != 0 { |
| 73 | s += fmt.Sprintf(": HTTP %d", e.StatusCode) |
| 74 | } |
| 75 | if e.Err != nil { |
| 76 | s += ": " + e.Err.Error() |
| 77 | } |
| 78 | return strings.TrimSpace(s) |
| 79 | } |
| 80 | |
| 81 | // Unwrap returns the underlying error value. See the `errors` package for info. |
| 82 | func (e HandlerError) Unwrap() error { return e.Err } |
| 83 | |
| 84 | // randString returns a string of n random characters. |
| 85 | // It is not even remotely secure OR a proper distribution. |
| 86 | // But it's good enough for some things. It excludes certain |
| 87 | // confusing characters. |
| 88 | // If sameCase is false, then l, I, O, S, 1, and 0 are excluded. |
| 89 | // If sameCase is true, then uppercase letters are excluded in |
| 90 | // addition to l, o, 1, and 0. |
| 91 | func randString(n int, sameCase bool) string { |
| 92 | if n <= 0 { |
| 93 | return "" |
| 94 | } |
| 95 | dict := []byte("abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRTUVWXY23456789") |
| 96 | if sameCase { |
| 97 | dict = []byte("abcdefghijkmnpqrstuvwxyz23456789") |
| 98 | } |
| 99 | b := make([]byte, n) |
| 100 | for i := range b { |
| 101 | //nolint:gosec |
| 102 | b[i] = dict[weakrand.IntN(len(dict))] |
| 103 | } |
| 104 | return string(b) |
| 105 | } |
| 106 | |
| 107 | func trace() string { |
| 108 | if pc, file, line, ok := runtime.Caller(2); ok { |
| 109 | filename := path.Base(file) |
| 110 | pkgAndFuncName := path.Base(runtime.FuncForPC(pc).Name()) |
| 111 | return fmt.Sprintf("%s (%s:%d)", pkgAndFuncName, filename, line) |
| 112 | } |
| 113 | return "" |
| 114 | } |
| 115 | |
| 116 | // ErrorCtxKey is the context key to use when storing |
| 117 | // an error (for use with context.Context). |
| 118 | const ErrorCtxKey = caddy.CtxKey("handler_chain_error") |