AERC-TEMPLATES(7)      Miscellaneous Information Manual      AERC-TEMPLATES(7)

NAME
       aerc-templates - template file specification for aerc(1)

SYNOPSIS
       aerc uses the go text/template package for the template parsing. Refer
       to the go text/template documentation for the general syntax. The
       template syntax described below can be used for message template files
       and for dynamic formatting of some UI app.

       Template files are composed of headers, followed by a newline, followed
       by the body text.

       Example:

           X-Clacks-Overhead: GNU Terry Pratchett

           Hello,

           Greetings,
           Chuck

       If you have a template that doesn't add any header, it must be preceded
       by a newline, to avoid parsing parts of the body as header text.

       All headers defined in the template will have precedence over any
       headers that are initialized by aerc (e.g. Subject, To, From, Cc) when
       composing a new message, forwarding or replying.

MESSAGE DATA
       The following data can be used in templates. Though they are not all
       available always.

       Addresses
           An array of mail.Address. That can be used to add sender or
           recipient names to the template.

           •   {{.From}}: List of senders.
           •   {{.Peer}}: List of senders or To recipients if the message is
               from you.
           •   {{.To}}: List of To recipients. Not always Available.
           •   {{.ReplyTo}}: List of ReplyTo recipients. Not always Available.
           •   {{.Cc}}: List of Cc recipients. Not always Available.
           •   {{.Bcc}}: List of Cc recipients. Not always Available.
           •   {{.OriginalFrom}}: List of senders of the original message.
               Available for quoted reply and forward.

           Example:

           Get the name of the first sender.
               {{(index .From 0).Name}}
               {{index (.From | names) 0}}

           Get the email address of the first sender.
               {{(index .From 0).Address}}

       Date and Time
           The date and time information is always available and can be easily
           formatted.

           •   {{.Date}}: Date and time information when the compose window is
               opened.
           •   {{.OriginalDate}}: Date and time when the original message was
               received. Available for quoted reply and forward.

           To format the date fields, dateFormat and .Local are provided.
           Refer to the TEMPLATE FUNCTIONS section for details.

       Subject
           The subject of the email (ThreadPrefix will be empty unless
           threading is enabled).

               {{.ThreadPrefix}}{{if .ThreadFolded}}{{printf "{%d}" .ThreadCount}}{{end}}{{.Subject}}

           The subject of the email stripped of any Re: and Fwd: prefixes.

               {{.SubjectBase}}
       Threading
           When threading is enabled, these attributes are available in the
           message list:

           ThreadPrefix
               If the message is part of a thread, this will contain arrows
               that represent the message tree based on In-Reply-To and
               References headers.

           ThreadFolded
               Will be true if the message has thread children which are
               hidden by :fold.

           ThreadCount
               The number of messages in the thread.

           ThreadUnread
               The number of unread messages in the thread.

       Flags
           List of message flags, not available when composing, replying nor
           forwarding. This is a list of strings that may be converted to a
           single string with join.

               {{.Flags | join ""}}

       IsReplied, HasAttachment, IsFlagged, IsRecent, IsUnread, IsMarked,
       IsDraft
           Individual boolean flags. not available when composing, replying
           nor forwarding.

               {{if .IsFlagged}}★{{end}}

       Labels
           Message labels (for example notmuch tags). Not available when
           composing, replying nor forwarding. This is a list of strings that
           may be converted to a single string with join.

               {{.Labels | join " "}}

       Size
           The size of the message in bytes. Not available when composing,
           replying nor forwarding. It can be formatted with humanReadable.

               {{.Size | humanReadable}}

       Filename
           The full path of the message file. Not available when composing,
           replying nor forwarding. For the notmuch backend, it returns a
           random filename if there are multiple files associated with the
           message.

       Filenames
           A list of the full paths of the files associated with the message.
           For maildir this is always a list with a single element.  Not
           available when composing, replying nor forwarding.

       Any header value
           Any header value of the email.

               {{.Header "x-foo-bar"}}

           Any header values of the original forwared or replied message:

               {{.OriginalHeader "x-foo-bar"}}
       Message-ID
           The message-ID of the message.

               :term b4 am {{.MessageId}}

       MIME Type
           MIME type is available for quoted reply and forward.

           •   {{.OriginalMIMEType}}: MIME type info of quoted mail part.
               Usually text/plain or text/html.

       Original Message
           When using quoted reply or forward, the original message is
           available in a field called OriginalText.

               {{.OriginalText}}

       Signature
           The signature of the currently selected account obtained from
           signature-file or signature-cmd.

               {{.Signature}}

       Account info
           The current account name:

               {{.Account}}

           The current account's backend:

               {{.AccountBackend}}

           Currently selected mailbox folder:

               {{.Folder}}

           Current message counts for all folders:

               {{.Recent}} {{.Unread}} {{.Exists}}
               {{.RUE}}

           IANA role of the mailbox, converted to lowercase:

               {{.Role}}

           aerc implements two additional custom roles: A 'query' role is
           given to folders from a notmuch query-map and 'virtual' indicates a
           virtual node in the directory tree listing:

               {{if eq .Role "query"}}{{...}}{{else}}{{...}}{{end}}

           Current message counts for specific folders:

               {{.Recent "inbox"}}
               {{.Unread "inbox" "aerc/pending"}}
               {{.Exists "archive" "spam" "foo/baz" "foo/bar"}}
               {{.RUE "inbox"}}

       Status line

           The following data will only be available in the status line
           templates:

           Connection state.

               {{.Connected}}
               {{.ConnectionInfo}}

           General status information (e.g. filter, search) separated with
           [statusline].separator.

               {{.ContentInfo}}

           Combination of {{.ConnectionInfo}} and {{.StatusInfo}} separated
           with [statusline].separator.

               {{.StatusInfo}}

           General on/off information (e.g. passthrough, threading, sorting,
           visual mode), separated with [statusline].separator.

               {{.TrayInfo}}

           Currently pressed key sequence that does not match any key binding
           and/or is incomplete.

               {{.PendingKeys}}

TEMPLATE FUNCTIONS
       Besides the standard functions described in go's text/template
       documentation, aerc provides the following additional functions:

       wrap
           Wrap the original text to the specified number of characters per
           line.

               {{wrap 72 .OriginalText}}

       quote
           Prepends each line with "> ".

               {{quote .OriginalText}}

       trimSignature
           Removes the signature froma passed in mail. Quoted signatures are
           kept as they are.

               {{trimSignature .OriginalText}}

       join
           Join the provided list of strings with a separator:

               {{.To | names | join ", "}}

       split
           Split a string into a string slice with a separator:

               {{.To | names | join ", " | split ", "}}

       names
           Extracts the names part from a mail.Address list. If there is no
           name available, the mbox (email address without @domain) is
           returned instead.

               {{.To | names | join ", "}}
               {{index (.To | names) 0}}

       firstnames
           Extracts the first names part from a mail.Address list. If there is
           no name available, the short mbox (start of email address without
           @domain) is returned instead.

               {{.To | firstnames | join ", "}}
               {{index (.To | firstnames) 0}}

       initials
           Extracts the initials from the names part from a mail.Address list.
           If there is no name available, the first letter of the email
           address is returned instead.

               {{.To | initials | join ", "}}
               {{index (.To | initials) 0}}

       emails
           Extracts the addresses part from a mail.Address list.

               {{.To | emails | join ", "}}
               {{index (.To | emails) 0}}

       mboxes
           Extracts the mbox part from a mail.Address list (i.e. smith from
           smith@example.com).

               {{.To | mboxes | join ", "}}
               {{index (.To | mboxes) 0}}

       shortmboxes
           Extracts the short mbox part from a mail.Address list (i.e. smith
           from smith.and.wesson@example.com).

               {{.To | shortmboxes | join ", "}}
               {{index (.To | shortmboxes) 0}}

       persons
           Formats a list of mail.Address into a list of strings containing
           the human readable form of RFC5322 (e.g. Firstname Lastname
           <email@address.tld>).

               {{.To | persons | join ", "}}
               {{index (.To | persons) 0}}

       .Attach
           Attaches a file to the message being composed.

               {{.Attach '/usr/libexec/aerc/filters/html'}}

       exec
           Execute external command, provide the second argument to its stdin.

               {{exec `/usr/libexec/aerc/filters/html` .OriginalText}}

       .Local
           Convert the date to the local timezone as specified by the locale.

               {{.Date.Local}}

       dateFormat
           Format date and time according to the format passed as the second
           argument. The format must be specified according to go's time
           package format.

               {{dateFormat .Date "Mon Jan 2 15:04:05 -0700 MST 2006"}}

           You can also use the .DateAutoFormat method to format the date
           according to *-time*format settings:

               {{.DateAutoFormat .OriginalDate.Local}}

       now
           Return the current date as a golang time.Time object that can be
           formatted with dateFormat.

               {{dateFormat now "Mon Jan 2 15:04:05 -0700 MST 2006"}}

       humanReadable
           Return the human readable form of an integer value.

               {{humanReadable 3217653721}}

       cwd
           Return the current working directory with the user home dir
           replaced by ~.

               {{cwd}}

       compactDir
           Reduce a directory path into a compact form. The directory name
           will be split with / and each part will be reduced to the first
           letter in its name: INBOX/01_WORK/PROJECT will become I/W/PROJECT.

               {{compactDir .Folder}}

       contains
           Checks if a string contains a substring.

               {{contains "<!DOCTYPE html>" .OriginalText}}

       hasPrefix
           Checks if a string has a prefix.

               {{hasPrefix "Business" .Folder}}

       toLower
           Convert a string to lowercase.

               {{toLower "SPECIAL OFFER!"}}

       toUpper
           Convert a string to uppercase.

               {{toUpper "important"}}

       replace
           Perform a regular expression substitution on the passed string.

               {{replace `(.+) - .+ at .+..+` `$1` ((index .OriginalFrom 0).Name)}}

       .Style
           Apply a user-defined style (see aerc-stylesets(7)) to a string.

               {{.Style .Account "red"}}
               {{.Style .ThreadPrefix "thread"}}{{.Subject}}

       .StyleSwitch
           Apply a user-defined style (see aerc-stylesets(7)) to a string if
           it matches one of the associated regular expressions. If the string
           does not match any of the expressions, leave it unstyled.

               {{.StyleSwitch .Subject (`^([[w-]+]s*)?[(RFC )?PATCH` "cyan")}}
               {{.StyleSwitch (.From | names | join ", ") (case `Tim` "cyan") (case `Robin` "pink-blink") (default "blue")}}

       .StyleMap
           Apply user-defined styles (see aerc-stylesets(7)) to elements of a
           string list. The logic is the same than .StyleSwitch but works on a
           list of elements. An additional exclude option is available to
           remove the matching elements from the list.

               {{.StyleMap .Labels (exclude .Folder) (exclude `^spam$`) (case `^inbox$` "red") (case `^Archive/.*` "green") (default "blue") | join " "}}

       version
           Returns the version of aerc, which can be useful for things like X-
           Mailer.

               X-Mailer: aerc {{version}}

       match
           Check if a string matches a regular expression. This is intended
           for use in conditional control flow:

               {{if match .Folder `.*/Archive-[0-9]+`}}{{humanReadable .Unread}}{{end}}

       switch
           Do swich/case/default control flows. The switch value is compared
           with regular expressions. If none of the case/default arms match,
           an empty string is returned.

               {{switch .Folder (case `^INBOX$` "📥") (case `^Archive/.*` "🗃") (default "📁")}}

       map
           Transform a string list into another one. The logic is the same
           than switch but works on a list of elements. An additional exclude
           option is available to remove the matching elements from the list.

               {{map .Labels (exclude .Folder) (exclude `^spam$`) (case `^inbox$` "📥") (case `^Archive/.*` "🗃") | join " "}}

       Function chaining
           All of the template functions can be chained together if needed.

           Example: Automatic HTML parsing for text/html mime type messages

               {{if eq .OriginalMIMEType "text/html"}}
               {{exec `/usr/libexec/aerc/filters/html` .OriginalText | wrap 72 | quote}}
               {{else}}
               {{wrap 72 .OriginalText | trimSignature | quote}}
               {{end}}

SEE ALSO
       aerc(1) aerc-config(5)

AUTHORS
       Originally created by Drew DeVault and maintained by Robin Jarry who is
       assisted by other open source contributors. For more information about
       aerc development, see https://sr.ht/~rjarry/aerc/.

                                  2024-07-30                 AERC-TEMPLATES(7)