json,haskell,aeson , Parsing JSON data from a URL in Haskell using Aeson


Parsing JSON data from a URL in Haskell using Aeson

Question:

Tag: json,haskell,aeson

I'm trying to create a web app in Haskell that takes some JSON input from a URL.

{-# LANGUAGE OverloadedStrings, DeriveGeneric #-}

import Data.Aeson as Q
import Data.Text
import Control.Applicative
import Control.Monad
import qualified Data.ByteString.Lazy as B
import Network.HTTP.Conduit (simpleHttp)
import GHC.Generics
--import Data.DateTime

data Temperatures = 
  Temperatures { date :: String
               , temperature :: Int
                 } deriving (Show, Generic)

instance FromJSON Temperatures
instance ToJSON Temperatures


jsonURL :: String
jsonURL = "http://www.phoric.eu/temperature"

getJSON :: IO B.ByteString
getJSON = simpleHttp jsonURL


main :: IO ()
main = do 
 d <- (eitherDecode <$> getJSON) :: IO (Either String Temperatures)
 case d of
  Left e   -> putStrLn e
  Right stuff -> print stuff

However, I'm getting the error at runtime:

Bradley$ runhaskell test.hs
The key "date" was not found

The JSON is below @ the URL which is in the code.

{"temperatures":[
    {"date":"2015-02-28T20:16:12+00:00", "temperature":0},
    {"date":"2015-01-01T21:46:55+00:00", "temperature":2}, 
    {"date":"2015-04-08T21:46:53+00:00", "temperature":3},
    {"date":"2015-04-09T21:46:01+00:00", "temperature":4},
    {"date":"2015-04-10T21:46:40+00:00", "temperature":5},
    {"date":"2015-04-11T21:46:36+00:00", "temperature":6},
    {"date":"2015-04-12T20:36:25+00:00", "temperature":7}
]}

I have no idea why it is not recognising the keys when they're clearly present in the JSON object, any ideas?


Answer:

In its current form, your code can only parse a single line of the form {"date":"2015-04-12T20:36:25+00:00", "temperature":7} : it tries to parse the input into a Temperatures, but can't find a date key into the root object because it only has a temperatures key.

The problem is that your Temperatures datatype does not really match your input. Here is something that should match:

data DataPoint = DataPoint { date :: String
                           , temperature :: Int
                           } deriving (Show, Generic)

data Temperatures = Temperatures { temperatures :: [DataPoint]
                                 } deriving (Show, Generic)

Related:


String comparison in AngularJS


javascript,json,angularjs,ionic-framework,string-comparison
I'm trying to compare two strings in AngularJS, and I've seen examples online. As I understand it, you can use angular.equals(str1, str2), you can use ===, you can use == if you're sure that both are strings... I've tried all three, but I don't get the result. Something must be...

Can't save json data to variable (or cache) with angularjs $http.get


json,angularjs,web-services,rest
I have weird angularjs problem. I'm trying to fetch data from Rest Webservice. It works fine, but I can't save json data to object. My code looks like: services.service('customerService', [ '$http', '$cacheFactory', function($http, $cacheFactory) { var cache = $cacheFactory('dataCache'); var result = cache.get('user'); this.getById = function(id){ $http.get(urlList.getCustomer + id).success(function(data, status,...

convert from json to array


javascript,php,json
I am trying to get data to display in a table. I don't know what I am doing wrong, but when I get the data from my page it is an array of single characters. I could parse this myself but would prefer to know what I am doing wrong....

How to parse JSON array of string arrays


c#,json
Lets say I get the following json data from a web service which I can't change. [ [ "Header1", "Header2", "Header3", "Header4" ], [ "FirstValue1", "FirstValue2", "FirstValue3", "FirstValue4" ], [ "SecondValue1", "SecondValue2", "SecondValue3", "SecondValue4" ] ] jsonlint.com tells me that it is valid json and from what I know I...

Use JSON file to insert data in database


javascript,json,mongodb,meteor,data
I'm using my JSON file like this to insert data in my collection : var content = JSON.parse(Assets.getText('test.json')); console.log('inserting...'); Profiles.insert({ user: id, data:content }; But I would like to have a "data's tree" like that : [ user: "rtegert23423131", firstname:"test", surname:"test2", // ... ] Not like that : [ user:...

why i don't get return value javascript


javascript,jquery,html,json,html5
When i debug my code i can see i have value but i don't get value to createCheckBoxPlatform FN function createCheckBoxPlatform(data) { var platform = ""; $.each(data, function (i, item) { platform += '<label><input type="checkbox" name="' + item.PlatformName + ' value="' + item.PlatformSK + '">' + item.PlatformName + '</label>' +...

Link to another resource in a REST API: by its ID, or by its URL?


json,api,rest,api-design,hateoas
I am creating some APIs using apiary, so the language used is JSON. Let's assume I need to represent this resource: { "id" : 9, "name" : "test", "customer_id" : 12, "user_id" : 1, "store_id" : 3, "notes" : "Lorem ipsum example long text" } Is it correct to refer...

Sencha/Extjs rest call with all parameters


json,rest,extjs,sencha-touch
I'm using ExtJs 5.1.1 and I've written a simple view with a grid, and selecting one row the corresponding model property are editable in some text fields. When editing is completed the button 'save' call Model.save() method, which use the rest proxy configured to write the changes on the server....

Codeigniter Select JSON, Insert JSON


json,codeigniter,select,insert,routing
I have very simple users database: user_id, user_name, user_email My model this: class Users extends CI_Model { private $table; private $table_fields; private $table_fields_join; function __construct() { parent::__construct(); $this->table = 'users'; $this->table_fields = array( $this->table.'.user_id', $this->table.'.user_name', $this->table.'.user_email' ); $this->table_fields_join = array(); } function select(){ $this->db->select(implode(', ', array_merge($this->table_fields, $this->table_fields_join)));...

'utf8' codec can't decode byte 0xf3


python,json,character-encoding
I am using python 2.7 to read the json file. my code is import json from json import JSONDecoder import os path=os.path.dirname(os.path.abspath(__file__))+'/json' print path for root, dirs, files in os.walk(os.path.dirname(path+'/json')): for f in files: if f.lower().endswith((".json")): fp=open(root + '/'+f) data = fp.read() print data.decode('utf-8') But I got the following error....

php array returns undefined but print_r shows otherwise [duplicate]


php,arrays,json,undefined
This question already has an answer here: PHP: “Notice: Undefined variable” and “Notice: Undefined index” 11 answers foreach($jsonmediationinfo as $value1) { echo $value1['mstatus']; print_r($jsonmediationinfo); } Output: 1Array ( [0] => Array ( [mstatus] => 1 [mhearingnum] => first [mminutes] => adakjaflafjlarjkelfkalfkd;la ) [1] => Array ( [mhearingnum] => second...

Complicated Json processing - PHP


php,json
I am using this JSON: http://steamcommunity.com/id/mitch8910/inventory/json/730/2/ I am sorting through the "rgDescriptions" data with this: $data = file_get_contents('http://steamcommunity.com/id/mitch8910/inventory/json/730/2/'); $json = json_decode($data); foreach ($json->rgDescriptions as $mydata) { //checking and adding data to a database } Each section in "rgDescriptions" contains a lot of information on a certain item. For each item...

Check for duplicates in JSON


javascript,jquery,json,duplicates
I have a json object: var object1 = [{ "value1": "1", "value2": "2", "value3": "3", }, { "value1": "1", "value2": "5", "value3": "7", }, { "value1": "6", "value2": "9", "value3": "5", }, { "value1": "6", "value2": "9", "value3": "5", }] Now I want to take each record out of that...

Insert data in collection at Meteor's startup


javascript,json,meteor,data,startup
I would like to insert data at Meteor's startup. (And after from a JSON file) At startup, I create a new account and I would like to insert data and link it to this account once this one created. This is the code that creates the new account at startup:...

Sorting in Ruby on rails


ruby-on-rails,json,sorting
I'm very new to Ruby on rails. I try to edit the following api. I want to sorting "can_go" which is true are shown at the top of list. I added this row before sending data, but the result is still order by "user_id". user_infos.sort { |a, b| - (a['can_go']<=>b['can_go'])...

How can I express foldr in terms of foldMap for type-aligned sequences?


haskell,types,monoids,type-variables,foldable
I'm playing around with type-aligned sequences, and in particular I'm messing around with the idea of folding them. A foldable type-aligned sequence looks something like this: class FoldableTA fm where foldMapTA :: Category h => (forall b c . a b c -> h b c) -> fm a b...

Replacing elements in an HTML file with JSON objects


javascript,json,replace
I am writing some Javascript to: Read in and Parse a JSON file Read in an HTML file (created as a template file) Replace elements in the HTML file with elements from the JSON file. It is only replacing the first element obj.verb. Can someone please help me figure out...

Nested JSON structure to build side-by-side d3.js charts


javascript,json,d3.js
I'm currently stuck on how to traverse a JSON structure (I created) in order to create side-by-side donut charts. I think I've created a bad structure, but would appreciate any advice. I'm working from Mike Bostock's example here: http://bl.ocks.org/mbostock/1305337 which uses a .csv file for source data. In that example...

JQuery mutiple post in the same time


javascript,php,jquery,json
I have three functions ,and every function post to special php page to get data.. and every function need some time because every php script need some time .. function nb1() { $.post("p1.php", { action: 1 }, function(data) { console.log(data); }, "json") .fail(function(data) { console.log("error"); }); } function nb2() {...

Haskell: When declaring a class, how can I use a type variable that is not immediately in the constructors?


haskell
I want to define a function, <-? to check whether an element is in a list/set/map. module Test where import qualified Data.Map as Map import qualified Data.Set as Set class Memberable a where (<-?) :: b -> a -> Bool instance Memberable [x] where (<-?) = elem instance Memberable (Map.Map...

do calculation inside JSONArray in Java


java,arrays,json
I have a simple issue but cannot solve it as I am not very good at algorithm! I have an JSONArray in this form: [{"values":[{"time":1434976493,"value":"50"}, {"time":1434976494,"value":"100"}],"counter":"counter1"}, {"values":[{"time":1434976493,"value":"200"}, {"time":1434976494,"value":"300"}],"counter":"counter2"}, {"values":[{"time":1434976493,"value":"400"}, {"time":1434976494,"value":"600"}],"counter":"total"}] What I want to do is to get the integer value for counter 1 and counter 2 and then divide...

SwiftyJSON Reading JSON Array issue


json,swift,swifty-json
I'm trying to read a json array data as below with my code but I'm getting empty result all the time while I can print the whole data. Please where would be my issue? I've read this topic but I couldn't get the result. Topic Link {"Cars":[{"Brand":"Alfa Romeo"},{"Brand":"Audi"},{"Brand":"BMW"},{"Brand":"Citroen"},{"Brand":"Dacia"},{"Brand":"Fiat"},.......... My code...

Combining Event and an attribute in threepenny-gui


haskell,threepenny-gui
I have an Event String which I want to sink into a textarea. This works fine, but now I want to combine the current value of a checkbox selection to this string. First I did this by using checkedChange of the checkbox which works, but has a problem. If the...

LineChart with C3 using JSON


json,c3
I can't understand because my chart is not working properly. Anything is displayed. Below my simple code: <div id="chartc3"></div> <script> var scene; $.getJSON('assets/json/chartc3.json', function(data) { scene=data; var chart = c3.generate({ bindto: '#chartc3', data: { json: scene, keys: { value: ['round','val'], } } }); }); </script> and the following json file:...

Parsing Google Custom Search API for Elasticsearch Documents


json,python-2.7,elasticsearch,google-search-api
After retrieving results from the Google Custom Search API and writing it to JSON, I want to parse that JSON to make valid Elasticsearch documents. You can configure a parent - child relationship for nested results. However, this relationship seems to not be inferred by the data structure itself. I've...

How to use ajax response JSON data?


javascript,jquery,ajax,json
I have made my ajax request, which works great and returns JSON. But how do i use it? My response is something like this [{ "id": "5", "reviewID": "2389", "serviceID": "50707", "title": "well done" }] Now in my success function I am trying to use the data like such: success:...

KendoUI Grid - Complex JSON with inconsistent keys


javascript,json,kendo-ui,kendo-grid
I know this is probably been asked before, but having tried to find an answer - I am guessing either I am not comprehending some of the answers right, or I am looking at the problem all wrong. I am using a complex SLC loopback query - and the api...

Serializing a java bean into a cookie: Is it bad?


java,json,cookies
In the organization that i work for, there was a serious debate about the following. Scenario: There is a POJO with 6 different properties all are of type Strings. These values need to be persisted as cookies so that it can be picked back when someone does a booking on...

Haskell IO - read from standard input directly to list


haskell
Haskell IO system is super hard to understand for me so i have question : How to read from standard input to list ? I know that there is function getLine :: IO String and interact. But i do not know how to convert the input to list so I...

How to work with django-rest-framework in the templates


json,django,django-templates,django-rest-framework
Please bear with me. I am just learning django-rest-framework. And I really can't seem to grab it. model: class Day(models.Model): date = models.DateField(default=date.today) class ToDo(models.Model): date = models.ForeignKey(Day) name = models.CharField(max_length=100) very_important = models.BooleanField(default=False) finished = models.BooleanField(default=False) normal view: def home(request): days = Day.objects.all() return render(request, 'test.html', { 'days':days })...

Call function on Server from iOS app - Objective C


ios,objective-c,json,server,backend
If you are familiar with Parse.com's Javascript SDK, this is what I am trying to do for my own server for my iOS app (Objective-c). I want to be able to send some a string to the function that is on my server, have the server run its function and...

apply a transformation with function inline


haskell
Starting from a simple case of "fold" (I used (+) but can be anything else): Prelude.foldl (+) 0 [10,20,30] is it possible apply an inline transformation similar to (that doesn't work): Prelude.foldl ((+) . (\x -> read x :: Int)) 0 ["10","20","30"] In case not, is there an alternative to...

Haskell do clause with multiple monad types


haskell,monads
I'm using a graphic library in Haskell called ThreePennyUI. In this library the main function returns a UI monad object. This causes me much headache as when I attempt to unpack IO values into local variables I receive errors complaining of different monad types. Here's an example of my problem:...

Haskell - generate and use the same random list


haskell,random
In Haskell, I'd like to generate a random list of Ints and use it throughout my program. My current solution causes the array to be created randomly each time I access/use it. How can I overcome this problem?...

access the json encoded object returned by php in jquery


php,jquery,ajax,json
I want to post some data to php function by ajax, then get the encoded json object that the php function will return, then I want to get the information (keys and values) from this object, but I don't know how, here is my code: $.ajax({ url: "functions.php", dataType: "JSON",...

Replace all [ ] with {} - as short as possible [on hold]


haskell
Given the code below: import Data.List; main = (readLn :: IO [Integer]) >>= print . subsequences It takes a list of integers from standard input (for example [1,2,3]) and outputs something like: [[],[1],[2],[1,2],[3],[1,3],[2,3],[1,2,3]] I want it to be like this: {},{1},{2},{1,2},{3},{1,3},{2,3},{1,2,3}} so my goal is to replace every [ and...

How to rearrange CSV / JSON keys columns? (Javascript)


javascript,json,csv,papaparse
I am converting a JSON object array to CSV using Papa Parse JavaScript Library. Is there a way to have the CSV columns arranged in a certain way. For e.g; I get the column as: OrderStatus, canOp, OpDesc, ID, OrderNumber, FinishTime, UOM, StartTime but would like to be arranged as:...

Fatal error catched by register_shutdown_function and update json_encode


php,json,fatal-error
I can catch a fatal error with register_shutdown_function('shutdown') function shutdown(){ $error = error_get_last(); $result['message'] = $error['message']; } and I have an echo json_encode($result); Unfortunately this echo json_encode shows nothing because json is not updated with the message of the fatal error. What can I do to fix this?...

Create n:m objects using json and sequelize?


javascript,json,node.js,sequelize.js
I am trying to learn sequelize, but am having trouble getting a n:m object created. So far I have my 2 models that create 3 tables (Store, Product, StoreProducts) and the models below: models/Store.js module.exports = (sequelize, DataTypes) => { return Store = sequelize.define('Store', { name: { type: DataTypes.STRING, },...

How can I get json objects without the object number?


javascript,jquery,json,rest
I have a simple json object that spits out 4 items that have completely different properties inside each one. I have got the json being displayed with the 4 objects that are called meta.work_content like so: [Object, Object, Object, Object] I can open these in console and see the objects...

PHP how to extract info from json string wtihout knowing the keys


php,json
I am querying a service if a person have phone number(s) (also maybe not). I have a json string (as return value) like the following: $json = '{"data":[{"tel1":"1102"},{"tel2":"3220"}],"found":true}'; I convert this string to json_decode() function. $jd = json_decode($json); Then I want to get the phone numbers only into an array...

How use jquery getJSON with a local variable


javascript,jquery,ajax,json,ace-editor
i want to extend the completions of Ace Editor, and i need a json of word, this is my code: function load_completions() { var object = $('#preview').attr('class'); $.ajax({ type: "POST", url: "test_editor_ajax.php", data: {action:'load_completion', object:object}, cache: false, success: function(json){ var adminCompleter = { getCompletions: function(editor, session, pos, prefix, callback) {...

Response 200 OK but Jquery shows error?


javascript,jquery,json
I am stuck in kind of a weird problem where I am trying to make a JSONP request to the Open Weather history API to get the weather information for the previous years on the a particular date. fetchHistoryUrl = 'http://78.46.48.103/data/3.0/days?day=0622&mode=list&lat=39.77476949&lon=-100.1953125'; $.ajax({ method: 'get', url: fetchHistoryUrl, success: function(response){ console.log(response); },...

How to transform $.post to $.ajax?


javascript,jquery,ajax,json,servlets
I have this $.post peace of code: $.post("../admin-login", { dataName:JSON.stringify({ username:uname, password:pass, }) }, function(data,status){ console.log("Data:"+data); answer = data; } ); and I wont to transform it to $.ajax. On the servlet side I am demanding request.getParamter("dataName") but I do not know how to write data: section in $.ajax so...

Getting front value from array/json


php,arrays,json
I want to get my image value wich could be images/thispicture.png for example. I have an Array or Json with some values, but the problem is i only want the image from array. This is what i get now from the array: {"image_intro":"images\/16748007940_1cc8f06622_small.jpg","float_intro":"","image_intro_alt":"","image_intro_caption":"","image_fulltext":"","float_fulltext":"","image_fulltext_alt":"","image_fulltext_caption":""}"><img...

Why i get can not resolve method error in class android?


android,json
I use this tutorial: JSON and part of code to this: protected String doInBackground(String... urls) { TextView lbl=(TextView) findViewById(R.id.provCODE); person = new Person(); person.setName(lbl.getText().toString()); //person.setCountry("1853"); //person.setTwitter("1892"); return POST(urls[0],person); } but in the this line: person.setName(lbl.getText().toString()); i get this error: Can not resolve method. How can i solve that?what happen? my...

Deserializing Json data to c# for use in GridView - Error Data source is an invalid type


c#,json,gridview,serialization,.net-4.5
I am relatively new to working with C# (v5.0) and Json data (Newtonsoft.Json v6.0) and am seeking assistance in resolving an error when attempting to populate a .Net 4.5 GridView control. My sample Json data as returned by a web service is: { PersonDetails: [ { Book: "10 ", FirstName:...

Deserializing JSON into c# class


c#,json,couchdb
I have a JSON in the following format (from couchDB view) {"rows":[ {"key":["2015-04-01","524","http://www.sampleurl.com/"],"value":1}, {"key":["2015-04-01","524","http://www.sampleurl2.com/"],"value":2}, {"key":["2015-04-01","524","http://www.sampleurl3.com"],"value":1} ]} I need to create a "service" to get this data from couchDB and insert it on SQL Server (for generating reports..) in a efficient way. My first bet was to bulk insert this json...

Uncaught error: Invalid type for google table column


javascript,json,google-maps,google-visualization
I recently started using google visualization due to its simplicity. But while implementing in my recent project i seem to have run into a bit of trouble. The program shown is used to pull data from a JSON object and utilize it to display data in the google tables. Now...

Parse JSON output from AlamoFire


json,swift,nsurlrequest
I am using the latest Alamofire to manage a GET http request to my server. I am using the following to GET and parse the JSON: Alamofire.request(.GET, "*******") .responseJSON {(request, response, JSON, error) in if let statusesArray = JSON as? NSArray{ if let aStatus = statusesArray[0] as? NSDictionary{ //OUTPUT SHOWN...