Documentation

Overview

    Package mime implements parts of the MIME spec.

    Index

    Examples

    Constants

    View Source
    const (
    	// BEncoding represents Base64 encoding scheme as defined by RFC 2045.
    	BEncoding = WordEncoder('b')
    	// QEncoding represents the Q-encoding scheme as defined by RFC 2047.
    	QEncoding = WordEncoder('q')
    )

    Variables

    View Source
    var ErrInvalidMediaParameter = errors.New("mime: invalid media parameter")

      ErrInvalidMediaParameter is returned by ParseMediaType if the media type value was found but there was an error parsing the optional parameters

      Functions

      func AddExtensionType

      func AddExtensionType(ext, typ string) error

        AddExtensionType sets the MIME type associated with the extension ext to typ. The extension should begin with a leading dot, as in ".html".

        func ExtensionsByType

        func ExtensionsByType(typ string) ([]string, error)

          ExtensionsByType returns the extensions known to be associated with the MIME type typ. The returned extensions will each begin with a leading dot, as in ".html". When typ has no associated extensions, ExtensionsByType returns an nil slice.

          func FormatMediaType

          func FormatMediaType(t string, param map[string]string) string

            FormatMediaType serializes mediatype t and the parameters param as a media type conforming to RFC 2045 and RFC 2616. The type and parameter names are written in lower-case. When any of the arguments result in a standard violation then FormatMediaType returns the empty string.

            Example

            Code:

            package main
            
            import (
            	"fmt"
            	"mime"
            )
            
            func main() {
            	mediatype := "text/html"
            	params := map[string]string{
            		"charset": "utf-8",
            	}
            
            	result := mime.FormatMediaType(mediatype, params)
            
            	fmt.Println("result:", result)
            }
            
            result: text/html; charset=utf-8
            

            func ParseMediaType

            func ParseMediaType(v string) (mediatype string, params map[string]string, err error)

              ParseMediaType parses a media type value and any optional parameters, per RFC 1521. Media types are the values in Content-Type and Content-Disposition headers (RFC 2183). On success, ParseMediaType returns the media type converted to lowercase and trimmed of white space and a non-nil map. If there is an error parsing the optional parameter, the media type will be returned along with the error ErrInvalidMediaParameter. The returned map, params, maps from the lowercase attribute to the attribute value with its case preserved.

              Example

              Code:

              package main
              
              import (
              	"fmt"
              	"mime"
              )
              
              func main() {
              	mediatype, params, err := mime.ParseMediaType("text/html; charset=utf-8")
              	if err != nil {
              		panic(err)
              	}
              
              	fmt.Println("type:", mediatype)
              	fmt.Println("charset:", params["charset"])
              }
              
              type: text/html
              charset: utf-8
              

              func TypeByExtension

              func TypeByExtension(ext string) string

                TypeByExtension returns the MIME type associated with the file extension ext. The extension ext should begin with a leading dot, as in ".html". When ext has no associated type, TypeByExtension returns "".

                Extensions are looked up first case-sensitively, then case-insensitively.

                The built-in table is small but on unix it is augmented by the local system's mime.types file(s) if available under one or more of these names:

                /etc/mime.types
                /etc/apache2/mime.types
                /etc/apache/mime.types
                

                On Windows, MIME types are extracted from the registry.

                Text types have the charset parameter set to "utf-8" by default.

                Types

                type WordDecoder

                type WordDecoder struct {
                	// CharsetReader, if non-nil, defines a function to generate
                	// charset-conversion readers, converting from the provided
                	// charset into UTF-8.
                	// Charsets are always lower-case. utf-8, iso-8859-1 and us-ascii charsets
                	// are handled by default.
                	// One of the CharsetReader's result values must be non-nil.
                	CharsetReader func(charset string, input io.Reader) (io.Reader, error)
                }

                  A WordDecoder decodes MIME headers containing RFC 2047 encoded-words.

                  func (*WordDecoder) Decode

                  func (d *WordDecoder) Decode(word string) (string, error)

                    Decode decodes an RFC 2047 encoded-word.

                    Example

                    Code:

                    package main
                    
                    import (
                    	"bytes"
                    	"fmt"
                    	"io"
                    	"mime"
                    )
                    
                    func main() {
                    	dec := new(mime.WordDecoder)
                    	header, err := dec.Decode("=?utf-8?q?=C2=A1Hola,_se=C3=B1or!?=")
                    	if err != nil {
                    		panic(err)
                    	}
                    	fmt.Println(header)
                    
                    	dec.CharsetReader = func(charset string, input io.Reader) (io.Reader, error) {
                    		switch charset {
                    		case "x-case":
                    			// Fake character set for example.
                    			// Real use would integrate with packages such
                    			// as code.google.com/p/go-charset
                    			content, err := io.ReadAll(input)
                    			if err != nil {
                    				return nil, err
                    			}
                    			return bytes.NewReader(bytes.ToUpper(content)), nil
                    		default:
                    			return nil, fmt.Errorf("unhandled charset %q", charset)
                    		}
                    	}
                    	header, err = dec.Decode("=?x-case?q?hello!?=")
                    	if err != nil {
                    		panic(err)
                    	}
                    	fmt.Println(header)
                    }
                    
                    ¡Hola, señor!
                    HELLO!
                    

                    func (*WordDecoder) DecodeHeader

                    func (d *WordDecoder) DecodeHeader(header string) (string, error)

                      DecodeHeader decodes all encoded-words of the given string. It returns an error if and only if CharsetReader of d returns an error.

                      Example

                      Code:

                      package main
                      
                      import (
                      	"bytes"
                      	"fmt"
                      	"io"
                      	"mime"
                      )
                      
                      func main() {
                      	dec := new(mime.WordDecoder)
                      	header, err := dec.DecodeHeader("=?utf-8?q?=C3=89ric?= <eric@example.org>, =?utf-8?q?Ana=C3=AFs?= <anais@example.org>")
                      	if err != nil {
                      		panic(err)
                      	}
                      	fmt.Println(header)
                      
                      	header, err = dec.DecodeHeader("=?utf-8?q?=C2=A1Hola,?= =?utf-8?q?_se=C3=B1or!?=")
                      	if err != nil {
                      		panic(err)
                      	}
                      	fmt.Println(header)
                      
                      	dec.CharsetReader = func(charset string, input io.Reader) (io.Reader, error) {
                      		switch charset {
                      		case "x-case":
                      			// Fake character set for example.
                      			// Real use would integrate with packages such
                      			// as code.google.com/p/go-charset
                      			content, err := io.ReadAll(input)
                      			if err != nil {
                      				return nil, err
                      			}
                      			return bytes.NewReader(bytes.ToUpper(content)), nil
                      		default:
                      			return nil, fmt.Errorf("unhandled charset %q", charset)
                      		}
                      	}
                      	header, err = dec.DecodeHeader("=?x-case?q?hello_?= =?x-case?q?world!?=")
                      	if err != nil {
                      		panic(err)
                      	}
                      	fmt.Println(header)
                      }
                      
                      Éric <eric@example.org>, Anaïs <anais@example.org>
                      ¡Hola, señor!
                      HELLO WORLD!
                      

                      type WordEncoder

                      type WordEncoder byte

                        A WordEncoder is an RFC 2047 encoded-word encoder.

                        func (WordEncoder) Encode

                        func (e WordEncoder) Encode(charset, s string) string

                          Encode returns the encoded-word form of s. If s is ASCII without special characters, it is returned unchanged. The provided charset is the IANA charset name of s. It is case insensitive.

                          Example

                          Code:

                          package main
                          
                          import (
                          	"fmt"
                          	"mime"
                          )
                          
                          func main() {
                          	fmt.Println(mime.QEncoding.Encode("utf-8", "¡Hola, señor!"))
                          	fmt.Println(mime.QEncoding.Encode("utf-8", "Hello!"))
                          	fmt.Println(mime.BEncoding.Encode("UTF-8", "¡Hola, señor!"))
                          	fmt.Println(mime.QEncoding.Encode("ISO-8859-1", "Caf\xE9"))
                          }
                          
                          =?utf-8?q?=C2=A1Hola,_se=C3=B1or!?=
                          Hello!
                          =?UTF-8?b?wqFIb2xhLCBzZcOxb3Ih?=
                          =?ISO-8859-1?q?Caf=E9?=
                          
                          GOOS=linux, GOARCH=amd64

                          Directories

                          Path Synopsis
                          Package multipart implements MIME multipart parsing, as defined in RFC 2046.
                          Package multipart implements MIME multipart parsing, as defined in RFC 2046.
                          Package quotedprintable implements quoted-printable encoding as specified by RFC 2045.
                          Package quotedprintable implements quoted-printable encoding as specified by RFC 2045.