Consider a REST URL like /api/users/findByCriteria which receives POSTed JSON that contains details of the criteria, and outputs a list of Users.
How would one call this with Restangular so that its results are similar to Restangulars getList()?
Restangular.all('users').post("findByCriteria", crit)... might work, but I don't know how to have Restangular recognize that the result will be a list of Users
Restangular.all('users').getListFromPOST("findByCriteria", crit)... would be nice to be able to do, but it doesn't exist.
Doing a GET instead of a POST isn't an option, because the criteria is complex.
Well,
I experience same problem and I workaround it with plain function, which return a plain array of objects. but it will remove all Restangular helper functions. So, you cant use it.
Code snippet:
Restangular.one('client').post('list',JSON.stringify({
offset: offset,
length: length
})).then(
function(data) {
$scope.clients = data.plain();
},
function(data) {
//error handling
}
);
You can get a POST to return a properly restangularized collection by setting a custom handler for OnElemRestangularized in a config block. This handler is called after the object has been Restangularized. isCollection is passed in to show if the obect was treated as a collection or single element. In the code below, if the object is an array, but was not treated as collection, it is restangularized again, as a collection. This adds all the restangular handlers to each element in the array.
let onElemR = (changedElem, isCollection, route, Restangular: restangular.IService) => {
if (Array.isArray(changedElem) && !isCollection ) {
return Restangular.restangularizeCollection(null, changedElem, changedElem.route);
}
return changedElem;
};
RestangularProvider.setOnElemRestangularized(onElemR);
Related
I was using OMDBapi to get the details of different movies. I successfully fetched the result and it returns a json object like this;
{"Title":"WWA: The Inception","Year":"2001","Rated":"N/A","Released":"26 Oct 2001","Runtime":"N/A","Genre":"Action, Sport","Director":"N/A","Writer":"Jeremy Borash","Actors":"Bret Hart, Jeff Jarrett, Brian James, David Heath","Plot":"N/A","Language":"English","Country":"Australia","Awards":"N/A","Poster":"https://m.media-amazon.com/images/M/MV5BNTEyNGJjMTMtZjZhZC00ODFkLWIyYzktN2JjMTcwMmY5MDJlXkEyXkFqcGdeQXVyNDkwMzY5NjQ#._V1_SX300.jpg","Ratings":[{"Source":"Internet Movie Database","Value":"6.0/10"}],"Metascore":"N/A","imdbRating":"6.0","imdbVotes":"22","imdbID":"tt0311992","Type":"movie","DVD":"N/A","BoxOffice":"N/A","Production":"N/A","Website":"N/A","Response":"True"}
Note that we get this type of object from the api if we want to get a particular movie details and that is what i was doing. Now to show the different details to a user, i started parsing this JSON object which works fine but when i try to get the value of the Value key present inside the Ratings key, it returns undefined.
I am working with react-native. After getting the data, i stored it inside the state, named it as details. Then to get it;
this.state.details.Title //if i wanted to get the Title and it works fine.
Then for Value inside Ratings;
this.state.details.Ratings[0].Value
But it returns undefined.
Also note that this works fine in pure Javascript as i parsed the dict in the browser console in the same way and it returned the correct value.
Here is more code;
componentDidMount() {
this.fetchData();
}
fetchData = async () => {
const response = await fetch(`http://www.omdbapi.com/?i=${this.props.navigation.getParam('i')}&apikey=******`) // where this.props.navigation.getParam('i') is the omdbid of the movie
const result = await response.json()
this.setState({details: result})
}
Here is error log;
undefined is not an object (evaluating 'this.state.details.Ratings[0]')
You're most likely trying to access state object before fetch has done it's job .... it's an async op ... so you should make sure your data is ready before rendering...
if (this.state.details) {
// start rendering...
}
More Explanation
your setState function should be executed right after fetch has finished its job, and since it's an async operation, it's going to take some time ...During that time, render function is executed with no state.details --> causing your issue ...
That's why you should check for state before rendering ... besides, the optional chaining trick Silversky Technology mentioned in his answer
If the value property you are accessing from the object might be not available for all the movies in the data you are getting from API response so it might cause you to error when accessing key from undefined objects.
To overcome the issue there is a way, you can try a fix as below:
this.state.details.Ratings[0]?.Value
The ? symbol lets the javascript not give an error when the value key not available in the object. it will make the accessing of property optional.
When storing objects in states it often causes problems as you are doing in line
this.setState({details: result})
Save result after strigifying it like
JSON.stringify(result)
this.setState({details: result})
Then when fetching form state, parse it back to object by
var result = JSON.parse(this.state.details)
Then you should be able to access it
You can access Ratings[0].Value by
this.state.details.Ratings && this.state.details.Ratings[0].Value
like,
<Text> {this.state.details.Ratings && this.state.details.Ratings[0].Value} </Text>
This is a slightly messy questions. Although it appears I'm asking question about amCharts, I really just trying to figure how to extract an array from HTTP request and then turn it into a variable and place it in to 3-party javacript.
It all starts here, with this question, which was kindly answered by AmCharts support.
As one can see from the plnker. The chart is working. Data for the chart is hard coded:
`var chartData = [{date: new Date(2015,2,31,0,0,0, 0),value:372.10,volume:2506100},{date: new Date(2015,3,1,0, 0, 0, 0),value:370.26,volume:2458100},{date: new Date(2015,3,2,0, 0, 0, 0),value:372.25,volume:1875300},{date: new Date(2015,3,6,0, 0, 0, 0),value:377.04,volume:3050700}];`
So we know the amCharts part works. Know where the problem is changing hard coded data to a json request so it can be dynamic. I don't think this should be tremendously difficult, but for the life of me I can't seem figure it out.
The first issue is I can't find any documentation on .map, .subscribe, or .observable.
So here is a plunker that looks very similar to the first one, however it has an http providers and injectable. It's broken, because I can't figure out how to pull the data from the service an place it into the AmCharts function. I know how pull data from a http provider and display it in template using NgFor, but I don't need it in the template (view). As you can see, I'm successful in transferring the data from the service, with the getTitle() function.
this.chart_data =_dataService.getEntries();
console.log('Does this work? '+this.chart_data);
this.title = _dataService.getTitle();
console.log('This works '+this.title);
// Transfer the http request to chartData to it can go into Amcharts
// I think this should be string?
var chartData = this.chart_data;
So the ultimate question is why can't I use a service to get data, turn that data into a variable and place it into a chart. I suspect a few clues might be in options.json as the json might not be formatted correctly? Am I declaring the correct variables? Finally, it might have something to do with observable / map?
You have a few things here. First this is a class, keep it that way. By that I mean to move the functions you have inside your constructor out of it and make them methods of your class.
Second, you have this piece of code
this.chart_data =_dataService.getEntries().subscribe((data) => {
this.chart_data = data;
});
What happens inside subscribe runs asynchronously therefore this.chart_data won't exist out of it. What you're doing here is assigning the object itself, in this case what subscribe returns, not the http response. So you can simply put your library initialization inside of the subscribe and that'll work.
_dataService.getEntries().subscribe((data) => {
if (AmCharts.isReady) {
this.createStockChart(data);
} else {
AmCharts.ready(() => this.createStockChart(data));
}
});
Now, finally you have an interesting thing. In your JSON you have your date properties contain a string with new Date inside, that's nothing but a string and your library requires (for what I tested) a Date object, so you need to parse it. The problem here is that you can't parse nor stringify by default a Date object. We need to convert that string to a Date object.
Look at this snippet code, I used eval (PLEASE DON'T DO IT YOURSELF, IS JUST FOR SHOWING PURPOSES!)
let chartData = [];
for(let i = 0; i < data[0].chart_data.length; i++) {
chartData.push({
// FOR SHOWING PURPOSES ONLY, DON'T TRY IT AT HOME
// This will parse the string to an actual Date object
date : eval(data[0].chart_data[i].date);
value : data[0].chart_data[i].value;
volume : data[0].chart_data[i].volume;
});
}
Here what I'm doing is reconstructing the array so the values are as required.
For the latter case you'll have to construct your json using (new Date('YOUR DATE')).toJSON() and you can parse it to a Date object using new Date(yourJSON) (referece Date.prototype.toJSON() - MDN). This is something you should resolve in your server side. Assuming you already solved that, your code should look as follows
// The date property in your json file should be stringified using new Date(...).toJSON()
date : new Date(data[0].chart_data[i].date);
Here's a plnkr with the evil eval. Remember, you have to send the date as a JSON from the server to your client and in your client you have to parse it to a Date.
I hope this helps you a little bit.
If the getEntries method of DataService returns an observable, you need to subscribe on it to get data:
_dataService.getEntries().subscribe(
(data) => {
this.chart_data = data;
});
Don't forget that data are received asynchronously from an HTTP call. The http.get method returns an observable (something "similar" to promise) will receive the data in the future. But when the getEntries method returns the data aren't there yet...
The getTitle is a synchronous method so you can call it the way you did.
So, I found that array elements can be accessed in Handlebars using:
{{myArray.2.nestedObject}} and {{myArray.0.nestedObject}}
..to get the third and first elements for instance. (handlebars-access-array-item)
Is there a way to get the last element from an array?
I tried creating a helper for it:
Handlebars.registerHelper("lastElement", function(array) {
return array.last(); //Array.prototype extension
});
...and calling it as follows in the template:
{{lastElement myArray}} or even {{lastElement myArray.lastElement nestedArray}}
Sadly, this doesn't work. Helper functions return strings apparently. What I need is a way to be able to do this even with multi-dimensional arrays.
Should work, I've tested it.
Template:
{{last foo}}
Data:
{foo : [1,2,3,4,5,6]}
Helper:
Handlebars.registerHelper("last", function(array) {
return array[array.length-1];
});
The above piece of code works fine in all the cases. But if the array passed if a null array, possibility of the handlebar function throwing error is there. Instead perform a null check and then return the value accordingly.
Here is a typical JQGrid JSON response:
{
"page":1,
"records":537,
"rows":[..],
"rowCount":10,
"total":54
}
Along with this, I want to send additional custom data. For example, I'd like to send the database time of the last search so that I can lazy-reload my grid whenever changes have occurred since then. Here is how I would like to send that data:
{
//Custom name-value pairs:
"nameValues":{"lastSearchTime":"2011/09/01:14:14:56"},
//Normal JSON data:
"page":1,
"records":537,
"rows":[..],
"rowCount":10,
"total":54
}
The problem is that JQGrid swallows up the JSON response rather than forwarding it to the gridComplete method. In other words, params is undefined in the following function:
function myGridComplete (params){
//params is undefined!
var JSONResponse = ?;//I need your help here!!!
globalGridVariables.lastSearchTime = JSONResponse.nameValues.lastSearchTime;
//Rest of grid complete method
..
}
Please let me know if there is a way to get access to the JSON response object in the gridComplete method, or if there is another supported way to add custom data to a JSON response.
Thanks much!
Note: I don't want to send this as a hidden column, because that would be inefficient.
You can use loadComplete instead of gridComplete. The loadComplete event has one parameter (for example data) which represent the full data from the server response inclusive all of your extensions.
Alternative you can rename the nameValues to userdata and use $('#list').jqGrid('getGridParam', 'userData') to get the value. See here for more information.
Moreover you can consider to use more HTTP caching (see here and here) for the aims which you described in your question.
You can use beforeProcessing that has the deserialized response and gets active before gridComplete and loadComplete.
For example:
beforeProcessing: function (data, status, xhr) {
myArray = data.rows;
}
And just to make it more clearer from the documentation:
Below is the execution order of the events when a ajax request is made
beforeRequest
loadBeforeSend
serializeGridData
loadError
beforeProcessing
gridComplete
loadComplete
Good evening everyone. I am currently using MVC 3 and I have a viewmodel that contains a property that is a List. I am currently using json2's JSON.stringify method to pass my viewmodel to my action method. While debugging I am noticing that all the simple properties are coming thru but the collection property is empty even though I know for sure that there is at least one object in the collection. I wanted to know if there is anyone that is running into the same issue. Below is the code that I am using to post to the action method:
$.post("/ReservationWizard/AddVehicleToReservation/",
JSON.stringify('#ViewData["modelAsJSON"]'),
function (data) {
if (data != null) {
$("#vehicle-selection-container").html(data);
$(".reservation-wizard-step").fadeIn();
}
});
The object #ViewData["modelAsJSON"] contains the following json and is passed to my action method
{"NumberOfVehicles":1,"VehiclesToService":[{"VehicleMakeId":0,"VehicleModelId":0}]}
As you can see the property "VehiclesToService" has one object but when it gets to my action method it is not translated to the corresponding object in the collection, but rather the collection is empty.
If anyone has any insight into this issue it would be greatly appreciated.
Thanks in advance.
UPDATE
OK after making the recommended changes and making the call to new JavaScriptSerializer().Serialize(#Model) this is the string that ultimately gets sent to my action method through the post
'{"NumberOfVehicles":1,"VehiclesToService":[{"VehicleMakeId":0,"VehicleModelId":0}]}'
I can debug and see the object that gets sent to my action method, but again the collection property is empty and I know that for sure there is at least one object in the collection.
The AddVehicleToReservation action method is declared as follows:
public ActionResult AddVehicleToReservation(VehicleSelection selections)
{
...
return PartialView("viewName", model);
}
Here's the problem:
JSON.stringify('#ViewData["modelAsJSON"]')
JSON.stringify is a client side function and you are passing as argument a list that's stored in the ViewData so I suppose that it ends up calling the .ToString() and you have
JSON.stringify('System.Collections.Generic.List<Foo>')
in your final HTML which obviously doesn't make much sense. Also don't forget that in order to pass parameters to the server using the $.post function the second parameter needs to be a javascript object which is not what JSON.stringify does (it generates a string). So you need to end up with HTML like this:
$.post(
'ReservationWizard/AddVehicleToReservation',
[ { id: 1, title: 'title 1' }, { id: 2, title: 'title 2' } ],
function (data) {
if (data != null) {
$('#vehicle-selection-container').html(data);
$('.reservation-wizard-step').fadeIn();
}
}
);
So to make this work you will first need to serialize this ViewData into JSON. You could use the JavaScriptSerializer class for this:
#{
var myList = new JavaScriptSerializer().Serialize(ViewData["modelAsJSON"]);
}
$.post(
'#Url.Action("AddVehicleToReservation", "ReservationWizard")',
// Don't use JSON.stringify: that makes JSON request and without
// proper content type header your sever won't be able to bind it
#myList,
function (data) {
if (data != null) {
$('#vehicle-selection-container').html(data);
$('.reservation-wizard-step').fadeIn();
}
}
);
And please don't use this ViewData. Make your views strongly typed and use view models.