From ea361d9d2c60c961c09332592bce8423b8c708f3 Mon Sep 17 00:00:00 2001
From: Steven Barth <steven@midlink.org>
Date: Sun, 4 Jan 2009 20:09:13 +0000
Subject: [PATCH] Introduce active (pulling) JSON-Decoder

---
 libs/json/luasrc/json.lua | 39 ++++++++++++++++++++++++++++++++++++++-
 1 file changed, 38 insertions(+), 1 deletion(-)

diff --git a/libs/json/luasrc/json.lua b/libs/json/luasrc/json.lua
index 5d1abcf48..26b540428 100644
--- a/libs/json/luasrc/json.lua
+++ b/libs/json/luasrc/json.lua
@@ -498,4 +498,41 @@ Decoder.parsers = {
 	['n'] = Decoder.parse_null,
 	['['] = Decoder.parse_array,
 	['{'] = Decoder.parse_object
-}
\ No newline at end of file
+}
+
+
+--- Create a new Active JSON-Decoder.
+-- @class	function
+-- @name	ActiveDecoder
+-- @param   customnull	Use luci.json.null instead of nil for decoding null
+-- @return  Active JSON-Decoder
+ActiveDecoder = util.class(Decoder)
+
+function ActiveDecoder.__init__(self, source, customnull)
+	Decoder.__init__(self, customnull)
+	self.source = source
+	self.chunk = nil
+	getmetatable(self).__call = self.get
+end
+
+
+--- Fetches one JSON-object from given source
+-- @return Decoded object
+function ActiveDecoder.get(self)
+	local chunk, src_err, object
+	if not self.chunk then
+		chunk, src_err = self.source()
+	else
+		chunk = self.chunk
+	end
+
+	self.chunk, object = self:dispatch(chunk, src_err, true)
+	return object
+end
+
+
+function ActiveDecoder.fetch(self)
+	local chunk, src_err = self.source()
+	assert(chunk or not src_err, src_err)
+	return chunk
+end
-- 
2.11.0