add RawJson

Author: treeform

README.md

@@ -298,3 +298,23 @@ type Entry = object
   }
 }""".fromJson(Entry)
 ```
+
+## Full support for raw-json.
+
+Sometimes you don't need to parse the json, but just send it or store it in the database. You can speed this up by using `RawJson` type. What it does is prevents full parsing of that json tree and instead returns it is a `RawJson` (`disticnt string`) type. You can then do anything you want with that. Store it in a database or pass it along to some other API. Or maybe parse it later again with jsony.
+
+```nim
+import jsony
+type
+  Message = object
+    id: uint64
+    data: RawJson
+
+let
+  messageData = """{"id":123,"data":{"page":"base64","arr":[1,2,3]}}"""
+  message = messageData.fromJson(Message)
+# make sure raw json was not parsed
+doAssert message.data.string == """{"page":"base64","arr":[1,2,3]}"""
+# make sure that dumping raw json produces same result
+doAssert message.toJson() == messageData
+```

src/jsony.nim

@@ -1,4 +1,4 @@
-import jsony/objvar, strutils, tables, sets, unicode, json, options, parseutils, typetraits
+import jsony/objvar, std/strutils, std/tables, std/sets, std/unicode, std/json, std/options, std/parseutils, std/typetraits
 
 type JsonError* = object of ValueError
 
@@ -10,6 +10,7 @@ when defined(release):
 type
   SomeTable*[K, V] = Table[K, V] | OrderedTable[K, V] |
     TableRef[K, V] | OrderedTableRef[K, V]
+  RawJson* = distinct string
 
 proc parseHook*[T](s: string, i: var int, v: var seq[T])
 proc parseHook*[T: enum](s: string, i: var int, v: var T)
@@ -842,6 +843,14 @@ proc dumpHook*(s: var string, v: JsonNode) =
     of JBool:
       s.dumpHook(v.getBool)
 
+proc parseHook*(s: string, i: var int, v: var RawJson) =
+  let oldI = i
+  skipValue(s, i)
+  v = s[oldI ..< i].RawJson
+
+proc dumpHook*(s: var string, v: RawJson) =
+  s.add v.string
+
 proc toJson*[T](v: T): string =
   dumpHook(result, v)
 

tests/all.nim

@@ -18,5 +18,6 @@ import test_tables
 import test_tojson
 import test_tuples
 import test_refs
+import test_rawjson
 
 echo "all tests pass"

tests/test_rawjson.nim

@@ -0,0 +1,14 @@
+import jsony
+
+type
+  Message = object
+    id: uint64
+    data: RawJson
+
+let
+  messageData = """{"id":123,"data":{"page":"base64","arr":[1,2,3]}}"""
+  message = messageData.fromJson(Message)
+# make sure raw json was not parsed
+doAssert message.data.string == """{"page":"base64","arr":[1,2,3]}"""
+# make sure that dumping raw json produces same result
+doAssert message.toJson() == messageData