I'm building a RESTful API and the endpoints I'm creating are using command objects to validate the request data. I'm trying to figure out the best way to render the validation errors as json. For xml responses I followed the recommendation in the Grails in Action book and did...
response.status = 403
render(contentType: "text/xml") {
errors {
eventSaleDataCommand.errors.fieldErrors.each { err ->
field(err.field)
message(g.message(error: err))
}
}
}
This works well for rendering xml responses so I'm wondering what the recommended approach for rendering json responses is?
I wanted to have some control of how the error gets displayed so for the json response I added:
def results = eventSaleDataCommand.errors.fieldErrors.toList()
def errors = []
for (error in results) {
errors.add([
'type' : 'invalid_entry',
'field' : error.field,
'rejected_value': error.rejectedValue,
'message' : error.defaultMessage
])
}
render errors as JSON
Problem with this approach is I'm using the Joda time plugin so I'm getting the following exception when I try to render the map as JSON:
Class org.codehaus.groovy.grails.web.converters.marshaller.json.GenericJavaBeanMarshaller can not access a member of class org.joda.time.tz.DateTimeZoneBuilder$PrecalculatedZone with modifiers "public".
Anyone know of a way around this?
How about?
render eventSaleDataCommand.errors.fieldErrors as JSON
Related
I have created a small Akka HTTP server to receive an uploaded file.
path("upload"){
uploadedFile("csv"){
case (metadata, file) =>{
println("file received " + file.length() );
complete("hahahah")
}
}
}
I can receive the file successfully but I cannot access other fields in this POST request. The field "csv" contains the file to be uploaded, while another field, "name", contains the user-defined name. I cannot access the data in "name". Can anybody give me some clues about how to get it?
You can use fromFields('user) to get user name. But unfortunately you will get this exception: java.lang.IllegalStateException: Substream Source cannot be materialized more than once It's known issue: https://github.com/akka/akka-http/issues/90
As workaround, you can use toStrictEntity directive:
toStrictEntity(3.seconds) {
formFields('user) { (user) =>
uploadedFile("csv") {
case (metadata, file) => {
println(s"file received by $user" + file.length())
complete("hahahah")
}
}
}
}
}
I don't think it's a good idea because you will read the entire request entity into memory and it works if you have the small entity.
As a better solution, you can implement your own uploadedFile directive that will extract needed parts and fields from your multipart form data, see uploadedFile source code as example: https://github.com/akka/akka-http/blob/v10.0.10/akka-http/src/main/scala/akka/http/scaladsl/server/directives/FileUploadDirectives.scala
I am creating Post Call using Akka-Http where user will fill the form and make a request.
I want to convert this form data to Scala Map[String, String]
Can any one tell how to do this.
here is the code Snippet
post {
entity(as[Multipart.FormData]) { body =>
complete { //How to process Multi Part Form data to Map
}
}
}
Thanks
Looks like you're looking for the formFieldMap directive.
(post & formFieldMap) { fields =>
doStuffWith(fields)
complete(...)
}
See the docs for more info.
My problem with Angular 2 that was not exist in AngularJS, that I was sending the error message as a string with backend API call in case I have error, with error status 401 as example, the problem now that I can't read this message from Angular2 http response message, while I can do that from AngularJS:
I tried the following codes and nothing was helpful:
Promise:
this._http.post('/login',{email: 'email#example.com', password: '123'})
.toPromise()
.then((resp) => console.log(resp), (error) => console.log(error));
Observable:
this._http.post('/login',{email: 'email#example.com', password: '123'})
.subscribe(response =>console.log(response), (error) => console.log(error));
And from back-end I send response as a text, for OK or Unauthorized, for OK i send back String token == UUID.randomUUID().toString();, for error I send back message like String error = " Invalid credentials ";, the problem is that the console.log works and print the text for success (token in this case), but in case error, its just prints: Response with status: 200 for URL: null.
If I change code to JSON.stringify(error) I get something like this:
{"_body":{},"status":401,"ok":false,"statusText":"Unauthorized","headers":{"null":["HTTP/1.1 401 Unauthorized"],"Access-Control-Allow-Headers":["Origin"," X-Requested-With"," Content-Type"," Accept"," Referer"," User-Agent"],"Access-Control-Allow-Met
hods":["POST"," GET"," PUT"," DELETE"," OPTIONS"],"Access-Control-Allow-Origin":["*"],"Allow":["*"],"Content-Length":["36"],"Content-Type":["text/plain; charset=utf-8"],"Date":["Tue"," 23 Aug 2016 14:53:25 GMT"]},"type":2,"url":null}
As you can see the error test not even mentioned inside the Object !!
I tried to change the response for error from backend to return json like this:
{
"message": "invalid email or password"
}
I can get the result inside _body, and I can only read it like this: console.log(error._body.message) ! but i feel its something wrong this way, and I don't want to response as a json in this case.
For angularjs (angular 1), its so simple just to print the response and everything is cool, while in angular 2 its a really problem.
What the problem, and how I can solve this issue without any refactor to backend?
Edit:
I'm using Angular 2.0.0-rc.4 and same for http : `"#angular/http": "2.0.0-rc.4"
Mothanfar
In my case I'm working with the Asp Web Api as back end,this thing is making me crazy as well, the only solution I found is transform in a json and read the message, I know is really ugly but works for me.
Regards.
CheckError(error: any) {
let servermsg: any = JSON.parse(error._body)["ModelState"]["Login"][0];
if (servermsg) {
this.showMsg = true;
this.msg = servermsg;
}
}
If you are returning JSON object from the server, you may use the below code at client side:
let errMsg: ErrorMessage = err.json();
console.log(errMsg.message)
export class ErrorMessage {
message:string;
}
I'm making a REST DELETE call, which returns a 204. In jQuery 1.8.3 this works, and hits the request.done callback. But if I use 1.9 it goes to request.fail with a parsererror in the textStatus and a 'SyntaxError: Unexpected end of input' in the errorThrown.
remove = function (complete) {
var self = this;
var request = $.ajax({
context: self,
url: "/v1/item/" + itemId,
dataType: "json",
type: "DELETE"
});
request.done(removeCallback);
request.fail(function (xhr, textStatus, errorThrown) {
alert(errorThrown);
});
},
Anyone know what has changed in 1.9 that would cause this to fail, and what needs to change in order to fix it?
So, answering my own question it looks like this is in fact the problem:
From the jQuery upgrade guide
jQuery.ajax returning a JSON result of an empty string
Prior to 1.9, an ajax call that expected a return data type of JSON or JSONP would consider a return value of an empty string to be a success case, but return a null to the success handler or promise. As of 1.9, an empty string returned for JSON data is considered to be malformed JSON (because it is); this will now throw an error. Use the error handler to catch such cases.
So, if remove the dataType
dataType: "json",
It works in jQuery 1.8.3 and 1.9.
An HTTP 204 response is not an empty string: it means there is no data. This is a valid response for delete and update operations.
This looks like a bug introduced in JQuery 1.9.
The reason removing the dataType property fixes this is because when it's set to "json" JQuery attempts to parse the content using JSON.parse and failing as a result. From the ticket:
This won't fail with any other dataType than "json" because the
regression is due to the re-alignment of parseJSON with native
JSON.parse (throwing an exception for null/undefined values).
Don't try the workaround suggested in the ticket of adding a handler for the 204 via the statusCode property, because both that handler and the error handler will be triggered. A possible solution is the following:
$.ajax(url, {
type: "DELETE",
dataType: "json",
error: function (error) {
if (error.status === 204) {
// Success stuff
}
else {
// fail
}
}});
I was having a very similar problem, and you helped my find my answer - so thank you. My solution, however is slightly different, so I figured I would share it.
As stated in the question, on the JQuery website it says:
Prior to 1.9, an ajax call that expected a return data type of JSON or JSONP would consider a return value of an empty string to be a success case, but return a null to the success handler or promise. As of 1.9, an empty string returned for JSON data is considered to be malformed JSON (because it is); this will now throw an error. Use the error handler to catch such cases.
I was passing JSON data to a method on my server with "void" as a return type because I did not need to do anything with returned data in the success function. You can no longer return null when passing JSON in an AJAX request in JQuery 1.9 +. This was possible in previous versions of JQuery however.
To stop getting an error and get the success function to fire instead, you must simply return valid JSON in your AJAX request. It doesn't matter what you pass, as long as it's valid, because (in my case anyways) you are not using the returned data.
The problem seems to be that jQuery treats the empty body (where Content-Length is 0) of a 204 response as "". Which is one interpretation, but the downside is that "" gets treated like any other response string. So if you have called jQuery.ajax() with the dataType:json option, jQuery tries to convert "" to an object and throws an exception ("" is invalid JSON).
jQuery catches the exception and recovers, but if you prefer to avoid the exception altogether (in your development environment) you might do something like the following. Add in the "converters" option to jQuery.ajax() and use it to change "" responses to nulls (I do this when dataType is json). Something like :
var ajax_options =
{
/* ... other options here */
"converters" :
{
"text json" :
function( result )
{
if ( result === "" ) result = null;
return jQuery.parseJSON( result );
}
}
};
var dfd = jQuery.ajax( ajax_options );
I am having difficulty accessing the returned JSON response data from the new Facebook JS SDK new Graph API calls.
For instance, in some of their docs where they are using the old way of using the SDK , they get a pointer to the data by response[0]
but here, it's showing that you need to use response.data[0] instead: http://developers.facebook.com/tools/console/ (click on fb.api — photo-albums)
So which is it? I know that with my code below, if I try using response[0] type of syntax to get at the returned JSON I get undefined.
If I use response[0].length I also get undefined
But if I try response.data[0].length I get 2 which I guess is the returned JSON or my 2 albums..I just don't know how to play with this returned object in terms of syntax and manipulating it, its properties, etc.
I want to in the end parse out the returned JSON using the jQuery parseJSON method but have no clue how to even pass the right syntax here for the response and just use that response object.
FB.api(uri, function(response)
{
alert("response: " + response);
// check for a valid response
if (response == "undefined" || response == null || !response || response.error)
{
alert("error occured");
return;
}
alert("response length: " + response.data.length);
}
this alert gave me 2 which makes sense. I have 2 albums.
then I tried something like response.data[0] and tried a jQuery parseJSON(response.data) or parseJSON(response.data[0]) on that and it does not work. So can someone explain the response object here as in regards to Facebook I guess? I see no docs about how to use that returned object at all and how it's constructed.
UPDATED:
Ok, so here's the entire parsing method attempt that I've stubbed out so far. I don't know if the jQuery parsing is 100% good code yet, I sort of stubbed that out but I can't even test that until I figure out how to use this response object coming back. I know it is returning JSON because I parsed another facebook response object in another method in the JS SDK so pretty sure that response[0] or response.data[0] will give you the JSON string.
function GetAllFacebookAlbums(userID, accessToken)
{
alert("inside GetAllFacebookAlbums(userID, acessToken)");
var dFacebookAlbums = {}; // dictionary
var uri = "/" + userID + "/albums?access_token=" + accessToken;
//var uri = "/me/albums";
alert("get albums uri: " + uri);
FB.api(uri, function(response)
{
alert("response: " + response);
// check for a valid response
if (response == "undefined" || response == null || !response || response.error)
{
alert("error occured");
return;
}
alert("response length: " + response.data.length);
for (var i=0, l=response.data.length; i<l; i++)
{
alert("response[key]: " + response.data[i].Name);
}
// parse JSON from response
var dJSONObjects = jQuery.parseJSON(response.data);
alert("dJSONObjects: " + dJSONObjects);
if (dJSONObjects.length == 0)
return;
// iterate through the dictionary of returned JSON objects
// and transform each to a custom facebookAlbum object
// then add each new FacebookAlbum to the final dictionary
// that will return a set of facebookAlbums
$.each(json.attributes, function () {
// add a new album to the dictionary
aFacebookAlbums[i] = FacebookAlbum(
jsonObject["id"],
jsonObject["name"],
jsonObject["location"],
jsonObject["count"],
jsonObject["link"]
);
});
});
return dFacebookAlbums;
}
It depends on the API being used. For the new Graph API single objects come back as top level object: http://graph.facebook.com/naitik -- where as collections come back with a top level data property which is an Array: http://graph.facebook.com/zuck/feed. There's also introspection to make things somewhat easier: http://developers.facebook.com/docs/api#introspection. FQL is the other popular API call, and this is where the top level response is array (think rows in SQL) which is why some examples use response[0]. Easiest thing is to just look at the response in your browser or via curl and see what it looks like.
just to clarify for all you folks who are new to FB.api (as I am) graph queries return different shaped data ... here are two examples:
FB.api('me/' function(returnData) { } ) would put the following data into returnData
{
"id": "592529630",
"name": "Hugh Abbott",
"first_name": "Hugh",
"last_name": "Abbott",
}
then if I said returnData.first_name I would get "Hugh"
If however my query was about my friends, I might run the following query
FB.api('me/friends/' function(returnData) { } )
And the shape of my data is now different:
"data": [
{
"name": "Tom Bell",
"id": "36801805"
},
{
"name": "Michael Royce",
"id": "199712888"
},
]
... so returnData is now a array ... in order to retrieve values, I would do something like the following.
returnData.data[0].name this would return "Tom Bell"
I hope this helps, as I spent a few hours wondering where I had gone wrong ... it turns out, it is all in the shape of the data !!!! good luck my friends.
Hugh
In general, the JS SDK doesn't return JSON object but it returns an object which is structured similar to the JSON Object.
Say for example : One is polling for user events data and according to the GRAPH API reference (http://developers.facebook.com/docs/reference/api/event), the returned data will have attributes as given http://developers.facebook.com/docs/reference/api/event.
The JSON object for the events data would be like this if you are using PHP SDK
Array ( [data] => Array ( [0] => Array ( [name] => sample event [start_time] => 2010-08-09T22:00:00+0000 [end_time] => 2010-08-10T01:00:00+0000 [location] => at office\ [id] => xxxxxxxx [rsvp_status] => attending )) [paging] => Array ( [previous] => hyperlink [next] => hyperlink ) )
But if you are using JS SDK, then the returned response will be like this
response.data[0...n].attributes of the particular table which you are accessing.
So, in the case of event table it will be like this :
response.data[0...n].name or response.data[0...n].id, response.data[0...n].end_time, etc
Did this ever get figured out. No one accepted anything.
alert("response[key]: " + response.data[i].Name);
The above code has Name and not name. Also, as Matti pointed out above, this works:
response.data[0].name
Just my two cents. #CoffeeAddict, accept answers to show some appreciation... Seems like someone with you rep would appreciate that. :o)
I haven't looked at the API, but I doubt FB would give you JSON encoded strings in an array. Have you tried just accessing response.data[0].someproperty?
If there is no error, then response.data should be the stuff you want (this will be an array in most cases) if you are using the new graph api. You could always just alert the JSON string if you are unsure what you are getting back.
I'm sure this must not be an issue anymore considering the Graph API explorer clearly displays the data in the form that it is returned. You are right about the difference in structure of the responses, but personally it has been useful to see what data is returned using the explorer and use the syntax accordingly.