I'm trying to add CORS headers to incoming requests but I've noticed that app.response.headers is an immutable map and app.request.response doesn't exist even though it appears in the documentation examples. So, to the OPTIONS request I'm replying using a new Shelf response, but I can't find a way to add any new headers to the response of the actual request. Any ideas?
#app.Interceptor(r"/api/.*", chainIdx: 1)
corsInterceptor() {
if (app.request.method == "OPTIONS") {
var response = new shelf.Response.ok("", headers: HEADERS);
app.chain.interrupt(statusCode: HttpStatus.OK, responseValue: response);
} else {
// app.request.response is not available
app.request.response.headers.add('Access-Control-Allow-Origin', '*');
app.chain.next();
}
}
I found the fix in the first piece of code inside the Interceptor documentation...:)
#app.Interceptor(r"/api/.*", chainIdx: 1)
corsInterceptor() {
if (app.request.method == "OPTIONS") {
var response = new shelf.Response.ok("", headers: HEADERS);
app.chain.interrupt(statusCode: HttpStatus.OK, responseValue: response);
} else {
app.chain.next(() => app.response.change(headers: HEADERS));
}
}
app.chain.next() can take a callback as argument, which is expected to return a Response object. In this case app.response.change() returns a response with the correct headers.
Related
I am struggling with making a http post call returning JSON in flutter. I keep getting a 500 error and I dont know what the issue is. I need to pass a username and password in the header and I think the issue is how im doing it. Here is the code.
Future<User> LoginUser(String username, String password ) async {
final response =
await http.post('http://xx.xxx.xxx.xxx/api/Login',
headers: {"Content-Type": "application/json", 'email' : username , 'password' : password });
if (response.statusCode == 200) {
// If the call to the server was successful, parse the JSON
return User.fromJson(json.decode(response.body));
} else {
// If that call was not successful, throw an error.
throw Exception('Failed to load user');
}
}
It wont get past the 200 check because it is getting a 500. I cant find any examples with passing 2 parameters in the header and the content type so im not sure im doing that correctly.
If we have to pass 2 arguments like key and any other data, Then follow the code(Only for Post Request)
Future<ClassType> callApi()async{
const String url="your/request/to/post/link/url";
const Uri=Uri.parse(url);
Map passValues={'token':'yOuRtOkEnkEy','user_id':'123456789'};
var body = json.encode(token);
var response;
try {
response = **await** http.post(
uri,
headers: {'Content-Type': 'application/json'},
body: body,
);
} catch (e) {
print(e);
}
if (response.statusCode == 200) {
var jsonString = response.body;
var jsonMap = json.decode(jsonString);
print(jsonMap);
} else {
print('API FAILED');
}
return response;
}
I tried looking for the solution in the forum but I was unable to find something similar to what I'm trying to achieve. I have a gateway script in an MPG which kinda looks like this:
session.INPUT.readAsJSON(function (error, json) {
if (error){
throw error;
} else {
var SAMLResponse = json['SAMLResponse'];
var RelayState = json['RelayState'];
var urlopen = require('urlopen');
var options = {
target: 'https://************.com/e32d32der2tj90g8h4',
method: 'POST',
headers: { 'HEADER_NAME' : 'VALUE'},
contentType: 'application/json',
timeout: 60,
sslClientProfile: 'ClientProfile',
data: {"SAMLResponse": SAMLResponse, "RelayState": RelayState}
};
urlopen.open(options, function(error, response) {
if (error) {
session.output.write("urlopen error: "+JSON.stringify(error));
} else {
var responseStatusCode = response.statusCode;
var responseReasonPhrase = response.reasonPhrase;
response.readAsBuffer(function(error, responseData){
if (error){
throw error;
} else {
session.output.write(responseData);
console.log(responseData);
}
});
}
});
}
});
I'm doing a POST request and the response I get from the urlopen function is an HTML page, how to I display the contents of that page in my browser? I need that to initiate a process flow. am I going in the wrong direction here? what's the best way to POST to a URI and display it's response in DataPower?
with regards to my experience with DataPower, I just started learning, So I might not be familiar with many of the concepts.
Thanks in Advance!
session.INPUT.readAsJSON() would indicate that you are receiving JSON data as the input (from the POST).
Since you are building this in a Multi-Protocol Gateway (MPGW) you need to set the Response type to non-xml if the response is HTML and if there is no backend call being made (other than the url-open()) you also must set the skip-backside=1 variable.
Is the scenario as:
JSON HTTP Request -> [MPGW] -> url-open() -> Backend server --|
HTTP Response <-----------------------------------------|
Or:
JSON HTTP Request -> [MPGW] -> url-open() --| (skip-backside)
HTTP Response <------------------------|
If there is no backend call I would recommend building this in a XML Firewall (XMLFW) service instead and set it to "loopback" and non-xml.
If there is a backend and that is where you are sending your HTML from the url-open() then only MPGW Response type needs to be set to non-xml.
If it is the second option the you can just set the payload and headers in GWS and just call the target (https://************.com/e32d32der2tj90g8h4) as teh MPGW backside connection, no need for the url-open().
I am posting stop object from angular2, this is the code
addStop(stop: IStop): Observable<IStop> {
let headers = new Headers({ 'Content-Type': 'application/json' });
let options = new RequestOptions({ headers: headers });
return this._http.post(this._tripsUrl, stop, options)
.map(this.extractData)
.catch(this.handleError);
}
this is net core code that should get the object but is not activated,
when I remove [FromBody] attribute, the service activated- but I am getting null
[Route("api/trips/{tripName}/stops")]
[HttpPost("")]
public async Task<IActionResult> Post(string tripName, [FromBody]Stop theStop)
{
if (ModelState.IsValid)
{
//some code
if (await _repository.SaveChangesAsync())
{
return //some code
}
}
return BadRequest("Bad Request");
}
need help, I am not finding the error
It was cors issue, I already defined cors in my web.config of my ASP.NET Core server, and get function worked OK, but the post function didn't work, the right way to define cors is written in this article: https://weblog.west-wind.com/posts/2016/Sep/26/ASPNET-Core-and-CORS-Gotchas
I am using route to handle http requests to my server. This is my current route code:
HttpServer.bind("127.0.0.1", 8080).then((server) {
new Router(server)
..filter(new RegExp(r'/.*'), addCorsHeaders)
..filter(new RegExp(r'/admin/.*'), authenticate)
..serve(userGetURL, method: 'GET').listen(userGetHandler)
..serve(userPostURL, method: 'POST').listen(userPostHandler);
});
I am trying to get JSON data that I am POSTing to a URL. The data will be used to get an entity from the database and return it as JSON to the caller. I am basically trying to create a server application that will handle all the data and a client application that will display it.
I cannot figure out how to get the data from a POST. Everything I have tried requires that I listen to the stream, but it is already being listened to. This is how I have been trying to get the POST data:
userPostHandler(HttpRequest req) {
req.listen((List<int> buffer) {
// Return the data back to the client.
res.write(new String.fromCharCodes(buffer));
res.close();
}
}
The problem is I get a Bad state: Stream has already been listened to. error.
EDIT: The filters
Future<bool> authenticate(HttpRequest req) {
if (req.method == 'POST') {
// Post data is not null
// Authenticate user
String userName = '';
String password = '';
User user = new User();
user.DBConnect().then((User user) {
return new Future.value(user.ValidateUser(userName, password));
});
}
}
Future<bool> addCorsHeaders(HttpRequest req) {
print('${req.method}: ${req.uri.path}');
req.response.headers.add('Access-Control-Allow-Origin', '*, ');
req.response.headers.add('Access-Control-Allow-Methods', 'POST, OPTIONS, GET');
req.response.headers.add('Access-Control-Allow-Headers',
'Origin, X-Requested-With, Content-Type, Accept');
return new Future.value(true);
}
I have never used the Route package but I wonder why you want to listen inside the Handler. Can't you just access the properties you want to process?
Otherwise you could try
req.asBroadcastStream().listen(...)
A BroadcastStream supports multiple listeners.
More information in this article Use Streams for Data
Using the following code I was able to get a POST working:
void main() {
HttpServer.bind("127.0.0.1", 8080).then((server) {
new Router(server)
..filter(new RegExp(r'/.*'), addCorsHeaders)
..filter(new RegExp(r'/admin/.*'), authenticate)
..serve(userGetURL, method: 'GET').listen(userGetHandler)
..serve(userPostURL, method: 'POST').listen(userPostHandler);
});
}
Future userPostHandler(HttpRequest req) {
bool headerSent = false;
// Start listening before writing to the response.
req.listen((List<int> buffer) {
if (!headerSent) {
req.response.write("User POST");
headerSent = true;
}
req.response.write(new String.fromCharCodes(buffer));
},
// Use onDone to close the response.
onDone: () => req.response.close()
);
}
Here is what I figured out. Any write to the response automatically drains the body and thus destroy the POST data. As mentioned here. Also, listening to the response is done asynchronously and thus must be completed before close() is called.
I am trying to make a POST request.
Here my code:
var myModel = new MydModel({
content: "ciao"
});
console.log(myModel.get("content")); // "ciao"
myModel.save();
If I look to the network activity it looks like this:
The response part {id:0, content:"", ……}
In the header part: Request Payload {"content":"ciao"}
Here my model:
define([], function () {
var MyModel = Backbone.Model.extend({
url: function url ()
{
return "http://localhost/users";
}
});
return MyModel;
});
Is it my problem or is it in the server part?
send/receive vs request/response
a server receives requests and sends responses
a client sends requests and receives responses
in short
if {id:0, content:"", ……} (the response) is wrong, it's your server
if {"content":"asdasdsa"} (the request) is wrong, it's your client
There is little problem with receiving JSON-payload that "Backbone-client" sends to your Apache-server.
All you need to do is to manually parse JSON-payload from input on the server side ("php://input", for PHP), like this:
if($_SERVER['REQUEST_METHOD'] == 'PUT' || $_SERVER['REQUEST_METHOD'] == 'POST') {
$postStr = file_get_contents("php://input");
//json_decode throws error or returns null if input is invalid json
try {
$json = json_decode($postStr, true);
if(empty($json)) {
throw new Exception("Not valid json");
}
//must not be json, try query str instead
} catch(Errfor $e) {
$postVars = parse_str($postStr);
foreach($postVars as $key=>$data) {
$_POST[$key] = $data;
}
}
}
Full explanation you can find here:
http://colinbookman.com/2014/04/08/php-puts-posts-and-backbone-js/