jyapayne/Nim
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

toJson, jsonTo, json (de)serialization for custom types; remove dependency on strtabs thanks to a hooking mechanism (#14563)

Browse source 
* json custom serialization; application for strtabs
* serialize using nesting
* make toJson more feature complete
* add since
* Revert "Improve JSON serialisation of strtabs (#14549)"

This reverts commit 7cb4ef26ad.

* better approach via mixin
* toJson, jsonTo
* fix test
* address comments
* move to jsonutils
* doc
* cleanups
* also test for js
* also test for vm
This commit is contained in:
Timothee Cour 2020-06-08 01:35:23 -07:00 • committed by GitHub
commit c7a1a7b8bf
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
5 changed files with 203 additions and 31 deletions
Download patch file Download diff file Expand all files Collapse all files

42
lib/pure/json.nim
View file

@ -140,6 +140,9 @@
## var j2 = %* {"name": "Isaac", "books": ["Robot Dreams"]}
## j2["details"] = %* {"age":35, "pi":3.1415}
## echo j2
##
## See also: std/jsonutils for hookable json serialization/deserialization
## of arbitrary types.
runnableExamples:
## Note: for JObject, key ordering is preserved, unlike in some languages,
@ -149,8 +152,10 @@ runnableExamples:
doAssert $(%* Foo()) == """{"a1":0,"a2":0,"a0":0,"a3":0,"a4":0}"""
import
hashes, tables, strtabs, strutils, lexbase, streams, macros, parsejson,
options
hashes, tables, strutils, lexbase, streams, macros, parsejson
import options # xxx remove this dependency using same approach as https://github.com/nim-lang/Nim/pull/14563
import std/private/since
export
tables.`$`
@ -353,14 +358,6 @@ proc `[]=`*(obj: JsonNode, key: string, val: JsonNode) {.inline.} =
assert(obj.kind == JObject)
obj.fields[key] = val
proc `%`*(table: StringTableRef): JsonNode =
## Generic constructor for JSON data. Creates a new ``JObject JsonNode``.
result = newJObject()
result["mode"] = %($table.mode)
var data = newJObject()
for k, v in table: data[k] = %v
result["data"] = data
proc `%`*[T: object](o: T): JsonNode =
## Construct JsonNode from tuples and objects.
result = newJObject()
@ -378,20 +375,20 @@ proc `%`*(o: enum): JsonNode =
## string. Creates a new ``JString JsonNode``.
result = %($o)
proc toJson(x: NimNode): NimNode {.compileTime.} =
proc toJsonImpl(x: NimNode): NimNode {.compileTime.} =
case x.kind
of nnkBracket: # array
if x.len == 0: return newCall(bindSym"newJArray")
result = newNimNode(nnkBracket)
for i in 0 ..< x.len:
result.add(toJson(x[i]))
result.add(toJsonImpl(x[i]))
result = newCall(bindSym("%", brOpen), result)
of nnkTableConstr: # object
if x.len == 0: return newCall(bindSym"newJObject")
result = newNimNode(nnkTableConstr)
for i in 0 ..< x.len:
x[i].expectKind nnkExprColonExpr
result.add newTree(nnkExprColonExpr, x[i][0], toJson(x[i][1]))
result.add newTree(nnkExprColonExpr, x[i][0], toJsonImpl(x[i][1]))
result = newCall(bindSym("%", brOpen), result)
of nnkCurly: # empty object
x.expectLen(0)
@ -399,7 +396,7 @@ proc toJson(x: NimNode): NimNode {.compileTime.} =
of nnkNilLit:
result = newCall(bindSym"newJNull")
of nnkPar:
if x.len == 1: result = toJson(x[0])
if x.len == 1: result = toJsonImpl(x[0])
else: result = newCall(bindSym("%", brOpen), x)
else:
result = newCall(bindSym("%", brOpen), x)
@ -407,7 +404,7 @@ proc toJson(x: NimNode): NimNode {.compileTime.} =
macro `%*`*(x: untyped): untyped =
## Convert an expression to a JsonNode directly, without having to specify
## `%` for every element.
result = toJson(x)
result = toJsonImpl(x)
proc `==`*(a, b: JsonNode): bool =
## Check two nodes for equality
@ -992,7 +989,6 @@ when defined(nimFixedForwardGeneric):
proc initFromJson[S,T](dst: var array[S,T]; jsonNode: JsonNode; jsonPath: var string)
proc initFromJson[T](dst: var Table[string,T]; jsonNode: JsonNode; jsonPath: var string)
proc initFromJson[T](dst: var OrderedTable[string,T]; jsonNode: JsonNode; jsonPath: var string)
proc initFromJson(dst: var StringTableRef; jsonNode: JsonNode; jsonPath: var string)
proc initFromJson[T](dst: var ref T; jsonNode: JsonNode; jsonPath: var string)
proc initFromJson[T](dst: var Option[T]; jsonNode: JsonNode; jsonPath: var string)
proc initFromJson[T: distinct](dst: var T; jsonNode: JsonNode; jsonPath: var string)
@ -1073,20 +1069,6 @@ when defined(nimFixedForwardGeneric):
initFromJson(mgetOrPut(dst, key, default(T)), jsonNode[key], jsonPath)
jsonPath.setLen originalJsonPathLen
proc mgetOrPut(tab: var StringTableRef, key: string): var string =
if not tab.hasKey(key): tab[key] = ""
result = tab[key]
proc initFromJson(dst: var StringTableRef; jsonNode: JsonNode; jsonPath: var string) =
dst = newStringTable(parseEnum[StringTableMode](jsonNode["mode"].getStr))
verifyJsonKind(jsonNode, {JObject}, jsonPath)
let originalJsonPathLen = jsonPath.len
for key in keys(jsonNode["data"].fields):
jsonPath.add '.'
jsonPath.add key
initFromJson(mgetOrPut(dst, key), jsonNode[key], jsonPath)
jsonPath.setLen originalJsonPathLen
proc initFromJson[T](dst: var ref T; jsonNode: JsonNode; jsonPath: var string) =
verifyJsonKind(jsonNode, {JObject, JNull}, jsonPath)
if jsonNode.kind == JNull: