Add partial_encode/2 function.

davisp · Mar 16, 2017 · 6801624 · 6801624
1 parent f7831e6
commit 6801624
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Showing 5 changed files with 61 additions and 15 deletions.
diff --git a/c_src/encoder.c b/c_src/encoder.c
@@ -601,16 +601,25 @@ enc_object_element(Encoder* e, int first, ERL_NIF_TERM curr, ERL_NIF_TERM* stack
     if(!first && !enc_comma(e)) {
         return enc_error(e, "internal_error");
     }
-    if(!enc_string(e, tuple[0])) {
-        return enc_obj_error(e, "invalid_object_member_key", tuple[0]);
-    }
-    if(!enc_colon(e)) {
-        return enc_error(e, "internal_error");
+    if(enif_compare(tuple[0], e->atoms->atom_partial_object) == 0) {
+        if(!enc_unknown(e, tuple[1])) {
+            return enc_error(e, "internal_error");
+        }
+        stack = enif_make_list_cell(env, curr, stack);
+        stack = enif_make_list_cell(env, e->atoms->ref_object, stack);
+        *stackp = stack;
+    } else {
+        if(!enc_string(e, tuple[0])) {
+            return enc_obj_error(e, "invalid_object_member_key", tuple[0]);
+        }
+        if(!enc_colon(e)) {
+            return enc_error(e, "internal_error");
+        }
+        stack = enif_make_list_cell(env, curr, stack);
+        stack = enif_make_list_cell(env, e->atoms->ref_object, stack);
+        stack = enif_make_list_cell(env, tuple[1], stack);
+        *stackp = stack;
     }
-    stack = enif_make_list_cell(env, curr, stack);
-    stack = enif_make_list_cell(env, e->atoms->ref_object, stack);
-    stack = enif_make_list_cell(env, tuple[1], stack);
-    *stackp = stack;
     return 0;
 }
 

diff --git a/c_src/jiffy.c b/c_src/jiffy.c
@@ -16,6 +16,7 @@ load(ErlNifEnv* env, void** priv, ERL_NIF_TERM info)
     st->atom_null = make_atom(env, "null");
     st->atom_true = make_atom(env, "true");
     st->atom_false = make_atom(env, "false");
+    st->atom_partial_object = make_atom(env, "$partial_object$");
     st->atom_bignum = make_atom(env, "bignum");
     st->atom_bignum_e = make_atom(env, "bignum_e");
     st->atom_bigdbl = make_atom(env, "bigdbl");

diff --git a/c_src/jiffy.h b/c_src/jiffy.h
@@ -19,6 +19,7 @@ typedef struct {
     ERL_NIF_TERM    atom_null;
     ERL_NIF_TERM    atom_true;
     ERL_NIF_TERM    atom_false;
+    ERL_NIF_TERM    atom_partial_object;
     ERL_NIF_TERM    atom_bignum;
     ERL_NIF_TERM    atom_bignum_e;
     ERL_NIF_TERM    atom_bigdbl;

diff --git a/src/jiffy.erl b/src/jiffy.erl
@@ -2,7 +2,7 @@
 % See the LICENSE file for more information.
 
 -module(jiffy).
--export([decode/1, decode/2, encode/1, encode/2]).
+-export([decode/1, decode/2, encode/1, encode/2, partial_encode/2]).
 -define(NOT_LOADED, not_loaded(?LINE)).
 
 -compile([no_native]).
@@ -19,17 +19,20 @@
                     | json_array()
                     | json_preencoded().
 
--type json_array()  :: [json_value()].
+-type json_array()  :: [json_value()|json_partial_array()].
 -type json_string() :: atom() | binary().
 -type json_number() :: integer() | float().
 
+-type json_partial_array() :: {'$partial_array$', iodata()}.
+-type json_partial_object() :: {'$partial_object$', iodata()}.
+
 -ifdef(JIFFY_NO_MAPS).
 
--type json_object() :: {[{json_string(),json_value()}]}.
+-type json_object() :: {[({json_string(),json_value()})|json_partial_object()]}.
 
 -else.
 
--type json_object() :: {[{json_string(),json_value()}]}
+-type json_object() :: {[({json_string(),json_value()})|json_partial_object()]}
                         | #{json_string() => json_value()}.
 
 -endif.
@@ -107,6 +110,16 @@ encode(Data, Options) ->
     end.
 
 
+-spec partial_encode(json_array(), encode_options()) -> json_partial_array();
+                    (json_object(), encode_options()) -> json_partial_object().
+partial_encode(Data, Options) when is_list(Data) ->
+    Json = iolist_to_binary(encode(Data, Options)),
+    {'$partial_array$', binary_part(Json, 1, byte_size(Json) - 2)};
+partial_encode(Data, Options) when is_tuple(Data) ->
+    Json = iolist_to_binary(encode(Data, Options)),
+    {'$partial_object$', binary_part(Json, 1, byte_size(Json) - 2)}.
+
+
 finish_decode({bignum, Value}) ->
     list_to_integer(binary_to_list(Value));
 finish_decode({bignum_e, Value}) ->
@@ -161,7 +174,7 @@ finish_encode([<<_/binary>>=B | Rest], Acc) ->
 finish_encode([Val | Rest], Acc) when is_integer(Val) ->
     Bin = list_to_binary(integer_to_list(Val)),
     finish_encode(Rest, [Bin | Acc]);
-finish_encode([{json, Json} | Rest], Acc) ->
+finish_encode([{RawJson, Json} | Rest], Acc) when RawJson =:= json; RawJson =:= '$partial_array$'; RawJson =:= '$partial_object$' ->
     finish_encode(Rest, [Json | Acc]);
 finish_encode([InvalidEjson | _], _) ->
     throw({error, {invalid_ejson, InvalidEjson}});

diff --git a/test/jiffy_16_preencode_tests.erl b/test/jiffy_16_preencode_tests.erl
@@ -17,6 +17,11 @@ gen(ok, {E1, J, E2}) ->
     {msg("~p", [E1]), [
         {"Encode", ?_assertEqual(J, enc(E1))},
         {"Decode", ?_assertEqual(E2, dec(J))}
+    ]};
+
+gen(ok, {E, J}) ->
+    {msg("~p", [E]), [
+        {"Encode", ?_assertEqual(J, enc(E))}
     ]}.
 
 %% gen(error, E) ->
@@ -45,7 +50,24 @@ cases(ok) ->
         , { [ {json, JSON}, {json, JSON} ], <<"[[1,\"a\"],[1,\"a\"]]">>, [ EJSON, EJSON ]}
         , { {[ {<<"a">>, {json, JSON}} ]}, <<"{\"a\":[1,\"a\"]}">>, {[ {<<"a">>, EJSON} ]}}
         ],
-    TopTests ++ BuriedTests.
+
+    PartialArray = jiffy:partial_encode([ 2, 3 ], []),
+    PartialArrayTests =
+        [ {[ PartialArray ], <<"[2,3]">>}
+        , {[ 1, PartialArray ], <<"[1,2,3]">>}
+        , {[ PartialArray, 4 ], <<"[2,3,4]">>}
+        , {[ 1, PartialArray, 4 ], <<"[1,2,3,4]">>}
+        ],
+
+    PartialObject = jiffy:partial_encode({[ {<<"ii">>, <<"two">>}, {<<"iii">>, 3} ]}, []),
+    PartialObjectTests =
+        [ {{[ PartialObject ]}, <<"{\"ii\":\"two\",\"iii\":3}">>}
+        , {{[ {<<"i">>, 1}, PartialObject ]}, <<"{\"i\":1,\"ii\":\"two\",\"iii\":3}">>}
+        , {{[ PartialObject, {<<"iv">>, 4} ]}, <<"{\"ii\":\"two\",\"iii\":3,\"iv\":4}">>}
+        , {{[ {<<"i">>, 1}, PartialObject, {<<"iv">>, 4} ]}, <<"{\"i\":1,\"ii\":\"two\",\"iii\":3,\"iv\":4}">>}
+        ],
+
+    TopTests ++ BuriedTests ++ PartialArrayTests ++ PartialObjectTests.
 
 %% cases(error) ->
 %%     [ {json, true}