Parser: add header parser

lib/Connection.js

@@ -6,7 +6,8 @@ var tls = require('tls'),
     isDate = require('util').isDate,
     utf7 = require('utf7').imap;
 
-var Parser = require('./Parser').Parser;
+var Parser = require('./Parser').Parser,
+    parseHeader = require('./Parser').parseHeader;
 
 var MAX_INT = 9007199254740992,
     KEEPALIVE_INTERVAL = 10000,
@@ -1135,6 +1136,8 @@ Connection.prototype._enqueue = function(fullcmd, promote, cb) {
   }
 };
 
+Connection.parseHeader = parseHeader; // from Parser.js
+
 module.exports = Connection;
 
 // utilities -------------------------------------------------------------------

lib/Parser.js

@@ -15,7 +15,9 @@ var CH_LF = 10,
     RE_LITERAL = /\{(\d+)\}$/,
     RE_UNTAGGED = /^\* (?:(OK|NO|BAD|BYE|FLAGS|LIST|LSUB|SEARCH|STATUS|CAPABILITY|NAMESPACE|PREAUTH|SORT)|(\d+) (EXPUNGE|FETCH|RECENT|EXISTS))(?: (?:\[([^\]]+)\] )?(.+))?$/i,
     RE_TAGGED = /^A(\d+) (OK|NO|BAD) (?:\[([^\]]+)\] )?(.+)$/i,
-    RE_CONTINUE = /^\+ (?:\[([^\]]+)\] )?(.+)$/i;
+    RE_CONTINUE = /^\+ (?:\[([^\]]+)\] )?(.+)$/i,
+    RE_CRLF = /\r\n/g,
+    RE_HDR = /^([^:]+):[ \t]?(.+)?$/;
 
 function Parser(stream, debug) {
   if (!(this instanceof Parser))
@@ -576,7 +578,42 @@ function convStr(str, literals) {
   return str;
 }
 
+function parseHeader(str) {
+  var lines = str.split(RE_CRLF),
+      len = lines.length,
+      modded = false,
+      header = {},
+      m, h;
+
+  for (var i = 0; i < len; ++i) {
+    if (lines[i].length === 0)
+      continue;
+    if (lines[i][0] === '\t' || lines[i][0] === ' ') {
+      // folded header content
+      // RFC2822 says to just remove the CRLF and not the whitespace following
+      // it, so we follow the RFC and include the leading whitespace ...
+      header[h][header[h].length - 1] += lines[i];
+    } else {
+      m = RE_HDR.exec(lines[i]);
+      if (m) {
+        h = m[1].toLowerCase();
+        if (m[2]) {
+          if (header[h] === undefined)
+            header[h] = [m[2]];
+          else
+            header[h].push(m[2]);
+        } else
+          header[h] = [''];
+      } else
+        break;
+    }
+  }
+
+  return header;
+}
+
 exports.Parser = Parser;
 exports.parseExpr = parseExpr;
 exports.parseEnvelopeAddresses = parseEnvelopeAddresses;
 exports.parseBodyStructure = parseBodyStructure;
+exports.parseHeader = parseHeader;