- The DTD should allow for future server capabilities whenever possible - new metadata, new security levels, etc.
- The DTD should be capable of representing posts that have not yet been submitted to the LiveJournal server. (Client offline mode, possible XML protocol, etc.)
- The resulting files should be readable and editable by humans.
"3 < 4" should not be represented as"3 &lt; 4" . Possibly we should use CDATA blocks and conventionally escape" as]]( *)>"" ; inelegant, but nowhere near as ugly as double-escaping characters. Suggestions welcome.]]$1 >" - When keywords in the existing protocol and terminology in common usage differ, we should use the latter for tag names.
Update: Fixed typo. This originally had two ATTLISTs for option and none for meta.
<!-- itemid is optional, in case the server hasn't seen this post yet -->
<!ELEMENT entry (subject?, date, security, (option | meta)*, body)>
<!ATTLIST entry itemid CDATA #IMPLIED
journal CDATA #REQUIRED>
<!-- ime short one-line text bits make better attributes than tag contents -->
<!ELEMENT subject EMPTY>
<!ATTLIST subject text CDATA #REQUIRED>
<!-- format for date is "yyyy-mm-dd hh:mm:ss", as is used elsewhere in LJ
seconds-since-epoch would be nice, but fails outside 1970-2038 range
allow empty date value, with tz, to let server do the timestamp -->
<!ELEMENT date EMPTY>
<!ATTLIST date value CDATA #IMPLIED
tz CDATA #IMPLIED>
<!-- use CDATA attribute, not enum, in case we add security types -->
<!ELEMENT security (group+ | mask)?>
<!ELEMENT group EMPTY>
<!ELEMENT mask EMPTY>
<!ATTLIST security type CDATA #REQUIRED>
<!ATTLIST group name CDATA #REQUIRED>
<!ATTLIST mask name CDATA #REQUIRED>
<!-- options are booleans; metas are values associated with predefined keys -->
<!ELEMENT option EMPTY>
<!ATTLIST option name CDATA #REQUIRED>
<!ELEMENT meta EMPTY>
<!ATTLIST meta name CDATA #REQUIRED
value CDATA #REQUIRED>
<!-- body of the entry -->
<!ELEMENT body (#PCDATA)>
Example entry, using this DTD:
<entry itemid="4758836" journal="alanj">
<subject text="Subject of my post"/>
<date value="2001-06-01 21:41:08"/>
<security type="custom">
<group name="Some friends"/>
<group name="Other friends"/>
</security>
<option name="nocomments"/>
<meta name="userpic" value="dazed"/>
<meta name="mood" value="confused"/>
<meta name="weather" value="63'F, mostly cloudy"/>
<body><![CDATA[
This is my post body. It has <b>bold</b> and <i>italics</i>. :->
It also has a CDATA close sequence ]] >, but that got escaped.
]]></body>
</entry>