Refer to json individual objects in cpp crow - json

Question

i am using a cpp crow library and i am having difficulty in accessing individual objects i am attaching my code here.
CROW_ROUTE(app,"/hello/<string>")
([](string name){
crow::json::wvalue x;
x["name"] = "llllds";
x["Town"] = "Texas";
x["nickname"] = "drax";
x["father"] = "Nethan";
if (name == "Nothing")
cout << "Bad Responce";
std::ostringstream os;
cout << name << " is the required query";
val = x[name];
return val;
And i want to return my name can anyone help me with this. Thanks in advance

Answer 1

I used JSON for Modern C++ within crow (https://github.com/nlohmann/json)
Here is an example CROW_ROUTE I wrote
CROW_ROUTE(app, "/palindromes/<string>/<string>")([](const request &req, response &res, string ID, string words){
palindromeHash.insert({ID, words}); //ignore this
nlohmann::json x;
x = getPalindromes(palindromeHash.at(ID));
palindromeHash.erase(ID); //ignore this
res.sendJSON(x);
});
//getPalindromesFunction()
nlohmann::json getPalindromes(string data){
nlohmann::json x;
unordered_map<string, bool> hashmap;
string word = "";
std::string::size_type i = data.find("%20");
while (i != std::string::npos){
data.erase(i, 3);
data.insert(i, " ");
i = data.find("%20", i);
}
for(int i = 0; i < data.size(); i++){
if(data[i] == ' '){
hashmap.insert({word, true});
word = "";
}
else{
word += data[i];
}
}
string temp;
vector<string> words;
int numValid = 0;
for(auto& i: hashmap){
temp = i.first;
reverse(temp.begin(), temp.end());
auto got = hashmap.find(temp);
if(got != hashmap.end()){
words.push_back(i.first);
numValid++;
}
}
x["words"] = words;
x["numValid"] = numValid;
return x;
}
As you can see it returns a JSON object x that holds palindromes. The sendJSON() function is something I added to crow_all.h. Add it under the struct response section on line 7215
void sendJSON(const nlohmann::json& data){
std::string response = data.dump();
add_header("Access-Control-Allow-Origin", "*");
add_header("Content-Type", "text/html");
write(response);
end();
}
Remember to include "json.h" in both main.cpp and crow_all.h. The res.sendJSON will send it to my JS file which can loop through the JSON with ease.
$.get("/palindromes/" + ID + "/" + curr_line, {}, function(response){
let x = JSON.parse(response); //This will allow JS to read the C++ JSON
for(let i = 0; i < x.words.length; i++){
term.write(x.words[i] + "\r\n");
}
}