Erlang Chicagoboss unable to get the correct JSON response - json

Question

In my controller file I have a method that reads the incoming HTTP request, reads the user data from the Database, encodes the result in JSON (using jsx) and sends it in response.
sensorusersdetails('GET', []) ->
Headers = [{'Access-Control-Allow-Origin', "*"},
{'Access-Control-Allow-Methods', "GET, OPTIONS"},
{'Content-Type', "application/json"},
{'Access-Control-Allow-Headers', "X-Requested-With"},
{'Access-Control-Max-Age', "180"}],
Building = Req:query_param("bld"),
io:format("User Data request from Node.js server~n~p~n",
[Req:query_params()]),
{{Year,Month,Day},{_,_,_}} = erlang:localtime(),
StrDate = lists:flatten(io_lib:format("~4..0w-~2..0w-~2..0w",
[Year,Month,Day])),
BUserDataList = boss_db:find(sensoruser_data, [{building, 'equals', Building}]),
io:format("Current Users Data stored in the database: ~n~p~n",[BUserDataList]),
MyUserJSONList = sensor_preapre_data(BUserDataList, StrDate),
io:format("The Present Date Sensor Users Data with Binary 1: ~n~p~n",[MyUserJSONList]),
MyUserJSONListLength = length(MyUserJSONList),
if MyUserJSONListLength > 0 ->
MyFinalList = sensor_data_final(MyUserJSONList),
io:format("The Present Date Sensor Users Data without Binary 2: ~n~p~n",[MyFinalList]),
{200, [MyFinalList], Headers};
%%{json, MyFinalList};
true ->
{200, "NO DATA FOUND", Headers}
%%{json, [{error, "NO DATA FOUND"}]}
end.
In the Chicagoboss Server logs I'm getting:
The Present Date Sensor Users Data with Binary 1:
[[<<"{\"username\":\"KPBatman1\",\"building\":\"A\",\"device\":\"Fitbit\",\"date\":\"2017-07-23\",\"calorie\":732,\"distance\":6.4399999999999995,\"elevation\":0,\"floor\":0,\"steps\":8}">>],
[<<"{\"username\":\"KPSuperman1\",\"building\":\"A\",\"device\":\"Jawbone\",\"date\":\"2017-07-23\",\"calorie\":0,\"distance\":0.0,\"elevation\":0,\"floor\":0,\"steps\":0}">>]]
The Present Date Sensor Users Data without Binary 2:
[["{\"username\":\"KPBatman1\",\"building\":\"A\",\"device\":\"Fitbit\",\"date\":\"2017-07-23\",\"calorie\":732,\"distance\":6.4399999999999995,\"elevation\":0,\"floor\":0,\"steps\":8}"],
["{\"username\":\"KPSuperman1\",\"building\":\"A\",\"device\":\"Jawbone\",\"date\":\"2017-07-23\",\"calorie\":0,\"distance\":0.0,\"elevation\":0,\"floor\":0,\"steps\":0}"]]
However, when I send the HTTP request - the JSON response I am getting:
{"username":"KPBatman1","building":"A","device":"Fitbit","date":"2017-07-23","calorie":732,"distance":6.4399999999999995,"elevation":0,"floor":0,"steps":8}
{"username":"KPSuperman1","building":"A","device":"Jawbone","date":"2017-07-23","calorie":0,"distance":0.0,"elevation":0,"floor":0,"steps":0}
What is the correct way to send JSON response?

Answer 1

However, when I send the HTTP request - the JSON response I am
getting:
{"username":"KPBatman1","building":"A", ...}
{"username":"KPSuperman1","building":"A", ...}
And? What did you expect/want to get?
The following code works for me because the output is what I expected to see:
-module(cb_tutorial_greeting_controller, [Req]).
-compile(export_all).
hello('GET', []) ->
Headers = [
{'Access-Control-Allow-Origin', "*"},
{'Access-Control-Allow-Methods', "GET, OPTIONS"},
{'Content-Type', "application/json"},
{'Access-Control-Allow-Headers', "X-Requested-With"},
{'Access-Control-Max-Age', "180"}
],
Data = [
[<<"{\"username\":\"KPBatman1\",\"building\":\"A\"}">>],
[<<"{\"username\":\"KPSuperman1\",\"building\":\"A\"}">>]
],
Json = jsx:encode(Data),
{200, Json, Headers}.
In my browser, I see:
[["{\"username\":\"KPBatman1\",\"building\":\"A\"}"],["{\"username\":\"KPSuperman1\",\"building\":\"A\"}"]]
Note that MyFinalList isn't even valid JSON:
13> Data = [["{\"a\":\"Batman\"}"], ["{\"b\":\"Superman\"}"]].
[["{\"a\":\"Batman\"}"],["{\"b\":\"Superman\"}"]]
14> jsx:is_json(Data).
false
See what I did there?