I'm trying to parse JSON data from URL and show the data in my app.
JSON Example (After accessing specific URL):
[{"placeID":"1","placeName":"Test Place","city":"New York","type":"Rest"..
How I can read this data and show a list of the places recieved from the API?
I've been trying ALL of the guides over the internet for parsing JSON data from URL with Android Studio and without. As a total beginner with Android developement, I couldn't make one working exmaple with json even when the author shared the final example for download. I hope you can help me in noob-friendly way and step by step or refer me to the right places.
Thank you!
I believe Android uses org.json as the JSON library, in which case something like this works to retrieve information about each place (assuming data is a valid JSON string)
try {
String data = "\"[{\"placeID\":\"1\",\"placeName\":\"Test Place\",\"city\":\"New York\",\"type\":\"Rest\"..";
JSONArray places = new JSONArray(data);
for (int i = 0; i < places.length(); i++)
JSONObject place = (JSONObject) places.get(i);
int id = place.getInt("id");
String name = place.getString("placeName");
String city = place.getString("city");
// etc...
// Do what you wish with the id, name, city and other variables.
// It loops through here for each item in the JSON variable.
}
} catch (JSONException e) {
e.printStackTrace();
}
This goes through each place in the JSON array and grabs some of the variables from it. It would probably be smart to create a data class and call it something like Place. You could then pass in the data with a constructor: new Place(id, name, city); (see this constructor for example: https://stackoverflow.com/a/22419370/5236779).
I want to store the result from a call to a Domino Access Service (DAS) in a localStorage however when I try to convert the result object to a JSON string I get an error.
With DAS you get the result as an Array e.g.:
[
{
"#entryid":"1-CD90722966A36D758025725800726168",
"#noteid":"16B46",
Does anyone know how I get rid of the square brackets or convert the Array quickly to a JSON object?
Here is a snippet of my code:
var REST = "./myREST.xsp/notesView";
$.getJSON(REST,function(data){
if(localStorage){
localStorage.setItem('myCatalog',JSON.stringify(data));
}
});
Brackets are part of the JSON syntax. They indicate that this is an array of objects. And as you point to a view it is very likely that you would get more than one object back (one for each entry in the view).
So if you are only interested in the first element you could do this:
var REST = "./myREST.xsp/notesView";
$.getJSON(REST,function(data){
if(localStorage){
var firstRecord = data[0] || {};
localStorage.setItem('myCatalog',JSON.stringify(firstRecord));
}
});
Otherwise, you would need to define a loop to handle each of the objects :-)
/John
my JSON response is as given below
JSON response is
{"code":201,"message":[["TEST Action","NA","30-11--2011"],["TEST Action 2","NA","30-11--2011"]]}.
i want to take the data correspond to 'message'.i used JSON Array.and got response as
JSON array response is
[["TEST Action","NA","30-11--2011"],["TEST Action 2","NA","30-11--2011"]].
Now how can i access each array in that?
You should expand on what you have done, what language you are using, etc. Normally, you should be able to index into the array with the standard notation. In python for example you can do something along the lines of json_data["message"][0] to access the first array and json_data["message"][1] to access the second.
something like :
var d = JSON.parse('{"code":201,"message":[["TEST Action","NA","30-11--2011"],["TEST Action 2","NA","30-11--2011"]]}')
and then you can access each array in message part as :
d.message.forEach(function(obj) { console.log(obj); });
I am using App42 for my mobile backend. I need to put date field in my JSON that I am saving and further do a query on it for date search. I am not able to find it in document. Can anybody please let me know what is the required date format to do this?
You are not mentioned that which SDK you are using.
I am posting an Android sample code for date search in App42 json storage.
String yourDate = Util.getUTCFormattedTimestamp();
JSONObject jsonData = new JSONObject();
jsonData.put("name", "sachin");
jsonData.put("DOB", yourDate);
// Inserting json document.
Storage storageObj = storage.insertJSONDocument("dbName", "collectionName", jsonData);
System.out.println(storageObj);
// building query.
Query query = QueryBuilder.build("DOB", yourDate, Operator.EQUALS);
// find documents by query.
Storage result = storage.findDocumentsByQuery("dbName", "collectionName", query);
System.out.println(result);
I'm trying to build a restful API and I'm struggling on how to serialize JSON data to a HTTP query string.
There are a number of mandatory and optional arguments that need to be passed in the request, e.g (represented as a JSON object below):
{
"-columns" : [
"name",
"column"
],
"-where" : {
"-or" : {
"customer_id" : 1,
"services" : "schedule"
}
},
"-limit" : 5,
"return" : "table"
}
I need to support a various number of different clients so I'm looking for a standardized way to convert this json object to a query string. Is there one, and how does it look?
Another alternative is to allow users to just pass along the json object in a message body, but I read that I should avoid it (HTTP GET with request body).
Any thoughts?
Edit for clarification:
Listing how some different languages encodes the given json object above:
jQuery using $.param: -columns[]=name&-columns[]=column&-where[-or][customer_id]=1&-where[-or][services]=schedule&-limit=5&return=column
PHP using http_build_query: -columns[0]=name&-columns[1]=column&-where[-or][customer_id]=1&-where[-or][services]=schedule&-limit=5&return=column
Perl using URI::query_form: -columns=name&-columns=column&-where=HASH(0x59d6eb8)&-limit=5&return=column
Perl using complex_to_query: -columns:0=name&-columns:1=column&-limit=5&-where.-or.customer_id=1&-where.-or.services=schedule&return=column
jQuery and PHP is very similar. Perl using complex_to_query is also pretty similar to them. But none look exactly the same.
URL-encode (https://en.wikipedia.org/wiki/Percent-encoding) your JSON text and put it into a single query string parameter. for example, if you want to pass {"val": 1}:
mysite.com/path?json=%7B%22val%22%3A%201%7D
Note that if your JSON gets too long then you will run into a URL length limitation problem. In which case I would use POST with a body (yes, I know, sending a POST when you want to fetch something is not "pure" and does not fit well into the REST paradigm, but neither is your domain specific JSON-based query language).
There is no single standard for JSON to query string serialization, so I made a comparison of some JSON serializers and the results are as follows:
JSON: {"_id":"5973782bdb9a930533b05cb2","isActive":true,"balance":"$1,446.35","age":32,"name":"Logan Keller","email":"logankeller#artiq.com","phone":"+1 (952) 533-2258","friends":[{"id":0,"name":"Colon Salazar"},{"id":1,"name":"French Mcneil"},{"id":2,"name":"Carol Martin"}],"favoriteFruit":"banana"}
Rison: (_id:'5973782bdb9a930533b05cb2',age:32,balance:'$1,446.35',email:'logankeller#artiq.com',favoriteFruit:banana,friends:!((id:0,name:'Colon Salazar'),(id:1,name:'French Mcneil'),(id:2,name:'Carol Martin')),isActive:!t,name:'Logan Keller',phone:'+1 (952) 533-2258')
O-Rison: _id:'5973782bdb9a930533b05cb2',age:32,balance:'$1,446.35',email:'logankeller#artiq.com',favoriteFruit:banana,friends:!((id:0,name:'Colon Salazar'),(id:1,name:'French Mcneil'),(id:2,name:'Carol Martin')),isActive:!t,name:'Logan Keller',phone:'+1 (952) 533-2258'
JSURL: ~(_id~'5973782bdb9a930533b05cb2~isActive~true~balance~'!1*2c446.35~age~32~name~'Logan*20Keller~email~'logankeller*40artiq.com~phone~'*2b1*20*28952*29*20533-2258~friends~(~(id~0~name~'Colon*20Salazar)~(id~1~name~'French*20Mcneil)~(id~2~name~'Carol*20Martin))~favoriteFruit~'banana)
QS: _id=5973782bdb9a930533b05cb2&isActive=true&balance=$1,446.35&age=32&name=Logan Keller&email=logankeller#artiq.com&phone=+1 (952) 533-2258&friends[0][id]=0&friends[0][name]=Colon Salazar&friends[1][id]=1&friends[1][name]=French Mcneil&friends[2][id]=2&friends[2][name]=Carol Martin&favoriteFruit=banana
URLON: $_id=5973782bdb9a930533b05cb2&isActive:true&balance=$1,446.35&age:32&name=Logan%20Keller&email=logankeller#artiq.com&phone=+1%20(952)%20533-2258&friends#$id:0&name=Colon%20Salazar;&$id:1&name=French%20Mcneil;&$id:2&name=Carol%20Martin;;&favoriteFruit=banana
QS-JSON: isActive=true&balance=%241%2C446.35&age=32&name=Logan+Keller&email=logankeller%40artiq.com&phone=%2B1+(952)+533-2258&friends(0).id=0&friends(0).name=Colon+Salazar&friends(1).id=1&friends(1).name=French+Mcneil&friends(2).id=2&friends(2).name=Carol+Martin&favoriteFruit=banana
The shortest among them is URL Object Notation.
How about you try this sending them as follows:
http://example.com/api/wtf?
[-columns][]=name&
[-columns][]=column&
[-where][-or][customer_id]=1&
[-where][-or][services]=schedule&
[-limit]=5&
[return]=table&
I tried with a REST Client
And on the server side (Ruby with Sinatra) I checked the params, it gives me exactly what you want. :-)
Another option might be node-querystring. It also uses a similar scheme to the ones you've so far listed.
It's available in both npm and bower, which is why I have been using it.
Works well for nested objects.
Passing complex objects as query parameters of a url.
In the example below, obj is the JSON object to pass into query parameters.
Injecting JSON object as query parameters:
value = JSON.stringify(obj);
URLSearchParams to convert a string to an object representing search params. toString to retain string type for appending to url:
queryParams = new URLSearchParams(value).toString();
Pass the query parameters using template literals:
url = `https://some-url.com?key=${queryParams}`;
Now url will contain the JSON object as query parameters under key (user-defined name)
Extracing JSON from url:
This is assuming you have access to the url (either as string or URL object)
url_obj = new URL(url); (only if url is NOT a URL object, otherwise ignore this step)
Extract all query parameters in the url:
queryParams = new URLSearchParams(url_obj.search);
Use the key to extract the specific value:
obj = JSON.parse(queryParams.get('key').slice(0, -1));
slice() is used to extract a tailing = in the query params which is not required.
Here obj will be the same object passed in the query params.
I recommend to try these steps in the web console to understand better.
You can test with JSON examples here: https://json.org/example.html