github.com/olliephillips/hugo@v0.42.2/hugolib/alias.go (about) 1 // Copyright 2017 The Hugo Authors. All rights reserved. 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 // http://www.apache.org/licenses/LICENSE-2.0 7 // 8 // Unless required by applicable law or agreed to in writing, software 9 // distributed under the License is distributed on an "AS IS" BASIS, 10 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 11 // See the License for the specific language governing permissions and 12 // limitations under the License. 13 14 package hugolib 15 16 import ( 17 "bytes" 18 "fmt" 19 "html/template" 20 "io" 21 "path/filepath" 22 "runtime" 23 "strings" 24 25 "github.com/gohugoio/hugo/tpl" 26 27 jww "github.com/spf13/jwalterweatherman" 28 29 "github.com/gohugoio/hugo/helpers" 30 ) 31 32 const ( 33 alias = "<!DOCTYPE html><html><head><title>{{ .Permalink }}</title><link rel=\"canonical\" href=\"{{ .Permalink }}\"/><meta name=\"robots\" content=\"noindex\"><meta http-equiv=\"content-type\" content=\"text/html; charset=utf-8\" /><meta http-equiv=\"refresh\" content=\"0; url={{ .Permalink }}\" /></head></html>" 34 aliasXHtml = "<!DOCTYPE html><html xmlns=\"http://www.w3.org/1999/xhtml\"><head><title>{{ .Permalink }}</title><link rel=\"canonical\" href=\"{{ .Permalink }}\"/><meta name=\"robots\" content=\"noindex\"><meta http-equiv=\"content-type\" content=\"text/html; charset=utf-8\" /><meta http-equiv=\"refresh\" content=\"0; url={{ .Permalink }}\" /></head></html>" 35 ) 36 37 var defaultAliasTemplates *template.Template 38 39 func init() { 40 //TODO(bep) consolidate 41 defaultAliasTemplates = template.New("") 42 template.Must(defaultAliasTemplates.New("alias").Parse(alias)) 43 template.Must(defaultAliasTemplates.New("alias-xhtml").Parse(aliasXHtml)) 44 } 45 46 type aliasHandler struct { 47 t tpl.TemplateFinder 48 log *jww.Notepad 49 allowRoot bool 50 } 51 52 func newAliasHandler(t tpl.TemplateFinder, l *jww.Notepad, allowRoot bool) aliasHandler { 53 return aliasHandler{t, l, allowRoot} 54 } 55 56 func (a aliasHandler) renderAlias(isXHTML bool, permalink string, page *Page) (io.Reader, error) { 57 t := "alias" 58 if isXHTML { 59 t = "alias-xhtml" 60 } 61 62 var templ *tpl.TemplateAdapter 63 64 if a.t != nil { 65 templ = a.t.Lookup("alias.html") 66 } 67 68 if templ == nil { 69 def := defaultAliasTemplates.Lookup(t) 70 if def != nil { 71 templ = &tpl.TemplateAdapter{Template: def} 72 } 73 74 } 75 data := struct { 76 Permalink string 77 Page *Page 78 }{ 79 permalink, 80 page, 81 } 82 83 buffer := new(bytes.Buffer) 84 err := templ.Execute(buffer, data) 85 if err != nil { 86 return nil, err 87 } 88 return buffer, nil 89 } 90 91 func (s *Site) writeDestAlias(path, permalink string, p *Page) (err error) { 92 return s.publishDestAlias(false, path, permalink, p) 93 } 94 95 func (s *Site) publishDestAlias(allowRoot bool, path, permalink string, p *Page) (err error) { 96 handler := newAliasHandler(s.Tmpl, s.Log, allowRoot) 97 98 isXHTML := strings.HasSuffix(path, ".xhtml") 99 100 s.Log.DEBUG.Println("creating alias:", path, "redirecting to", permalink) 101 102 targetPath, err := handler.targetPathAlias(path) 103 if err != nil { 104 return err 105 } 106 107 aliasContent, err := handler.renderAlias(isXHTML, permalink, p) 108 if err != nil { 109 return err 110 } 111 112 return s.publish(&s.PathSpec.ProcessingStats.Aliases, targetPath, aliasContent) 113 114 } 115 116 func (a aliasHandler) targetPathAlias(src string) (string, error) { 117 originalAlias := src 118 if len(src) <= 0 { 119 return "", fmt.Errorf("Alias \"\" is an empty string") 120 } 121 122 alias := filepath.Clean(src) 123 components := strings.Split(alias, helpers.FilePathSeparator) 124 125 if !a.allowRoot && alias == helpers.FilePathSeparator { 126 return "", fmt.Errorf("Alias \"%s\" resolves to website root directory", originalAlias) 127 } 128 129 // Validate against directory traversal 130 if components[0] == ".." { 131 return "", fmt.Errorf("Alias \"%s\" traverses outside the website root directory", originalAlias) 132 } 133 134 // Handle Windows file and directory naming restrictions 135 // See "Naming Files, Paths, and Namespaces" on MSDN 136 // https://msdn.microsoft.com/en-us/library/aa365247%28v=VS.85%29.aspx?f=255&MSPPError=-2147217396 137 msgs := []string{} 138 reservedNames := []string{"CON", "PRN", "AUX", "NUL", "COM0", "COM1", "COM2", "COM3", "COM4", "COM5", "COM6", "COM7", "COM8", "COM9", "LPT0", "LPT1", "LPT2", "LPT3", "LPT4", "LPT5", "LPT6", "LPT7", "LPT8", "LPT9"} 139 140 if strings.ContainsAny(alias, ":*?\"<>|") { 141 msgs = append(msgs, fmt.Sprintf("Alias \"%s\" contains invalid characters on Windows: : * ? \" < > |", originalAlias)) 142 } 143 for _, ch := range alias { 144 if ch < ' ' { 145 msgs = append(msgs, fmt.Sprintf("Alias \"%s\" contains ASCII control code (0x00 to 0x1F), invalid on Windows: : * ? \" < > |", originalAlias)) 146 continue 147 } 148 } 149 for _, comp := range components { 150 if strings.HasSuffix(comp, " ") || strings.HasSuffix(comp, ".") { 151 msgs = append(msgs, fmt.Sprintf("Alias \"%s\" contains component with a trailing space or period, problematic on Windows", originalAlias)) 152 } 153 for _, r := range reservedNames { 154 if comp == r { 155 msgs = append(msgs, fmt.Sprintf("Alias \"%s\" contains component with reserved name \"%s\" on Windows", originalAlias, r)) 156 } 157 } 158 } 159 if len(msgs) > 0 { 160 if runtime.GOOS == "windows" { 161 for _, m := range msgs { 162 a.log.ERROR.Println(m) 163 } 164 return "", fmt.Errorf("Cannot create \"%s\": Windows filename restriction", originalAlias) 165 } 166 for _, m := range msgs { 167 a.log.WARN.Println(m) 168 } 169 } 170 171 // Add the final touch 172 alias = strings.TrimPrefix(alias, helpers.FilePathSeparator) 173 if strings.HasSuffix(alias, helpers.FilePathSeparator) { 174 alias = alias + "index.html" 175 } else if !strings.HasSuffix(alias, ".html") { 176 alias = alias + helpers.FilePathSeparator + "index.html" 177 } 178 if originalAlias != alias { 179 a.log.INFO.Printf("Alias \"%s\" translated to \"%s\"\n", originalAlias, alias) 180 } 181 182 return alias, nil 183 }