How to access the data stored in JSON on the database?

Question

Using Corona: I have been struggling with this for over a day now. I have a json file in a collection in a database. I can get my document using its Id.

---

storageService:findAllDocuments(dbName, collectionName, App42CallBack)

function App42CallBack:onSuccess(object)

   for i=1, table.getn(object:getJsonDocList()) do

         local doc = object:getJsonDocList()[i]:getDocId()

   end

end

---

Great. I have my document. Now in my document's JSON file, there are values such as "level" = 4. How do I get 4? I need a detailed answer. I read about queries and such, but that only gets me the document all over again. I need the data inside the json file. In my debugger I see: Success is: My document information including my json data I have no idea how to get the data. Thanks.

Answer 1

Hi,

Once you have the success response, you can find your JSON doc using the below code snippet from which you can your desired keys:

function App42CallBack:onSuccess(object)

   for i=1, table.getn(object:getJsonDocList()) do

         local doc = object:getJsonDocList()[i]:getDocId()

         local jsonDoc = object:getJsonDocList()[i]:getJsonDoc()

   end

end

 

Let me know if it helps.

 

Regards,

Himanshu Sharma

Comments

I get the document, but I try to print the table using ipairs, and nothing shows. If I try to decode the json file using (JSON:decode()) or (json.decode() --- corona use), I get an error "expected string but got table". If I just print(jsonDoc) it shows "table: 0CD6B8A8" and other tables like that.

"From which  you can get your desired keys" <--- how do I do that.

So, I have the document. Now, how do I get into that document to fetch the data. I need to see an example of how to return 4. The above just returns the document.