json encoding: handle tuples as keys in hashes

Author: gorenje

priv/testflows/27d8dd0a4448e969/flows.json

@@ -0,0 +1 @@
+[{"disabled":false,"env":[],"id":"27d8dd0a4448e969","info":"","label":"[.core] json encoding - support tuples as hash keys","type":"tab"},{"crontab":"","id":"02ee5a691ee981c6","name":"","once":false,"onceDelay":0.1,"payload":"","payloadType":"date","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","topic":"","type":"inject","wires":[["af9c370b305358a5"]],"x":702,"y":754,"z":"27d8dd0a4448e969"},{"finalize":"","func":"Eval = fun(Expression) ->\n    {ok, Tokens, _} = erl_scan:string(binary_to_list(Expression)),\n    {ok, Term} = erl_parse:parse_term(Tokens),\n    Term\nend,\n\n#{ <<\"payload\">> := Payload } = Msg,\n\nMsg#{<<\"payload\">> => Eval(Payload)}\n","id":"1bf7fe98027e33dd","initialize":"","libs":[],"name":"parse config files","noerr":0,"outputs":1,"timeout":0,"type":"function","wires":[["0183ca667854228b"]],"x":312,"y":421,"z":"27d8dd0a4448e969"},{"field":"payload","fieldType":"msg","format":"erlang","id":"af9c370b305358a5","name":"","output":"str","syntax":"mustache","template":"[\n    {config_setting_one, #{\n        key_one =>\n            #{\n                {10, 15} => 10,\n                {16, 20} => 50,\n                {21, 25} => 30,\n                {26, 30} => 10\n            },\n        key_two =>\n            #{\n                {10, 15} => 10,\n                {16, 20} => 50,\n                {21, 25} => 30,\n                {26, 30} => 10\n            }\n    }},\n    \n    {config_setting_two, #{\n        key_three =>\n            #{\n                {atom, atom2} => 0.20,\n                {atom4, 12} => 0.20,\n                {234, atom3} => 0.20\n            },\n        key_four =>\n            #{\n                smp => 1,\n                {two,three,four} => 1,\n                {one} => 0.15,\n                {} => 0.10\n            }\n    }}\n].","type":"template","wires":[["1bf7fe98027e33dd"]],"x":1074,"y":543,"z":"27d8dd0a4448e969"},{"id":"0183ca667854228b","ignore_failure_if_succeed":false,"name":"","rules":[{"p":"payload","pt":"msg","t":"eql","to":"{\"config_setting_one\":{\"key_one\":[[[10,15],10],[[16,20],50],[[21,25],30],[[26,30],10]],\"key_two\":[[[10,15],10],[[16,20],50],[[21,25],30],[[26,30],10]]},\"config_setting_two\":{\"key_three\":[[[234,\"atom3\"],0.2],[[\"atom\",\"atom2\"],0.2],[[\"atom4\",12],0.2]],\"key_four\":[[\"smp\",1],[[],0.1],[[\"one\"],0.15],[[\"two\",\"three\",\"four\"],1]]}}","tot":"json"}],"type":"ut-assert-values","wires":[[]],"x":699,"y":211,"z":"27d8dd0a4448e969"}]

src/ered_messages.erl

@@ -247,6 +247,16 @@ encoder(Other, Encode) when is_binary(Other) ->
             io:format("Json Encoding Error ~p ~p~n", [E, S]),
             json:encode_value(binary_to_list(Other), Encode)
     end;
+encoder(Other, Encode) when is_map(Other) ->
+    %% need to handle "#{{tuple} => Value}" maps, assume that if an encoding
+    %% error does happen, that converting the map to a list will fix the
+    %% issue - this does work for the tuple-as-key issue.
+    try
+        json:encode_value(Other, Encode)
+    catch
+        error:_E:_S ->
+            json:encode_value(maps:to_list(Other), Encode)
+    end;
 encoder(Other, Encode) ->
     json:encode_value(Other, Encode).