Develop Reference

Blazor page's URL is interfering with component's call to API -- 400-Bad Request

My web-app is .Net 6, VS-2022 Blazor WASM-hosted.
I am having a problem with the URL for the API when being called from a component.
I have three files: page: VehicleList.razor, page: VehicleEdit.Razor and component: CRUD_Vehicle.razor.
The page flow is the user navigates to 'VehicleList' and has the ability to select a vehicle to EDIT via callback function. Once selected, the flow navigates to 'VehicleEdit' where some data needs to be passed to support the embedded sub-component 'CRUD_Vehicle'.
The problem is that URL to the 'VehicleEdit' looks like this with query-string data in a comma-delimited string AND it remains there when the CRUD-component is showing.
https://localhost:7777/vehicleedit/667?par=17,Bigelow,Active
When the user makes editing changes and SUBMITs the component, the HttpClient service gets called and fails with a 400-Bad Request. I am under the impression that the query-string interfers with the api URL. Please see below. Is there a way I could set the URL to not show the query-string and only have the base-address and the UID_VEHICLE like this?
https://localhost:7777/vehicleedit/667
public async Task<Vehicle> UpdateVehicle(Vehicle pVehicle) {
// Save the edited record.
HttpResponseMessage response = await httpClient.PutAsJsonAsync<Vehicle>($"/api/vehicle/{pVehicle.UID_VEHICLE}", pVehicle);
if (!response.IsSuccessStatusCode) {
// problems handling here.
Console.WriteLine($"UpdateVehicle() Error occurred, the status code is: {(int)response.StatusCode}: {response.StatusCode}" );
}
return await response.Content.ReadFromJsonAsync<Vehicle>();
}
I have a similar construction for the editing of the Customer object, but the page that shows the CRUD_Customer component has a simple URL and works perfectly to save data to the DB. The main difference is the URL for the VehicleEdit.razor. Your comments are welcome.
Thanks.
https://localhost:7777/customeredit/17

I downloaded Postman and entered the PUT transaction and the PUT RESULT showed there was an ERROR (based on DataAnnotation for the 'StartDate'-field) that was NOT caught at the client validation code. It turns out that the TITLE text was based on what the possible cause might be. But Postman showed me the exact reason why the PUT call failed.
So, my 'answer' is: Use Postman to simulate the 'httpClient.PutAsJsonAsync'-call to observe the result-details to pinpoint the reason for the '400-Bad Request' return from the service.

Pass parameters to Get request on swiftUI

I'm having trouble with passing in parameters to a get request. This request is intended to return a list of warehouses after the user entered some search parameters such as Date, State, ZIP and/or warehouse number, which is the only mandatory field. So when the search button is pressed the query is executed, but im getting this error:
2021-04-19 15:49:00 +0000
2021-11-02 13:06:44.670511-0600 WAREHOUSE_IOS-Master[3142:186324] GET method must not have a body
2021-11-02 13:06:44.670799-0600 WAREHOUSE_iOS-Master[3142:186324] Task <C7839029-C527-490E-8747-137012285F14>.<3> finished with error [-1103] Error Domain=NSURLErrorDomain Code=-1103 "resource exceeds maximum size" UserInfo={NSLocalizedDescription=resource exceeds maximum size,
error: invalidResponse
Okay so what im doing is passing a body to the get request that includes the search parameters as such:
struct WarehouseBody : Codable {
let dateRegistration : String?
let state : String?
let zip : String?
let warehouseNumber : String
}
and I'm expecting a response of this type:
struct WareHouseResponse: Codable {
let status: String?
let code: Int?
let responseCode, message: String?
let error: Bool?
let errorMessage: String?
let result: Result?
enum CodingKeys: String, CodingKey {
case status = "Status"
case code = "Code"
case responseCode = "ResponseCode"
case message = "Message"
case error = "Error"
case errorMessage = "ErrorMessage"
case result = "Result"
}
}
but according to what I've reading on other posts this is not the correct way of using a get request, but I really really need to do some testing. Is there a way that I can achieve this without needing to alter the backend? Just to mention that I ´m also the developer of the backend (c# using .net framework and dapper)so if the easiest way is to achieve this is by altering it I can also do that. Any ideas are very much appreciated.
On the backend I was thinking of implementing a post Request that sends the search parameters to the server and then a get request that pulls out the requested information, but I don't know if that's the correct approach. But this not feasible at the moment because the Web API are already publish and I cannot re publish with the changes at the moment, and is really urgent to test the response so that's why I would like to know if all this can be done from the front end first. Thank you very much for all the help!
Thank you very much for your help!
EDIT: Also I forgot to mention that the api has been previously tested on POSTMAN and is working perfectly.

Since iOS 13. you cannot pass in parameters to a GET request. There’s no easy way around this. You need to change your request from a GET to a POST on the backend. In my case, this was an easy task because I had access to the API source— but, if you don’t, just ask the backend team to change it, and pass in the parameters as in any other POST request. That should work.

You must log in before using this part of Bugzilla

I have an issue with this get request of bugzilla to get the page of bug_list of two bugs "http://10.0.6.199:8080/bugzilla/rest.cgi/bug?id=2313,3478?api_key=my_api_key"
The issue appeared when I write more than one bug id to get the page of bug_list, I get this response
{
"code" : 410,
"documentation" : "http://www.bugzilla.org/docs/tip/en/html/api/",
"error" : true,
"message" : "You must log in before using this part of Bugzilla."
}
but I have no issus when I write one id by this get request
http://10.0.6.199:8080/bugzilla/rest.cgi/bug/2313?api_key=my_api_key
Can any one tell me the problem with this get request link?

I got the problem, I should write '&' before api_key instead of '?'
http://10.0.6.199:8080/bugzilla/rest.cgi/bug?id=2313,3478&api_key=my_api_key
instead of
http://10.0.6.199:8080/bugzilla/rest.cgi/bug?id=2313,3478?api_key=my_api_key"

C# screen scraping an ASP.NET web forms page - POST request not completely working

Please bear with me for this slightly long winded description but I'm having a strange problem with C# screen scraping an ASP.NET web forms page. The steps I'm trying to do are as follows:-
1) The site is secured using basic authentication over HTTPS so I need to login appropriately.
2) I'm performing a GET request on the page to retrieve the __VIEWSTATE value (darn thing does nothing if I don't set this thing!)
3) Once logged in there are several form fields to complete then a submit button which POST's the form to the server
4) When the submit button is pressed the form is POST'd to the server and response is the same page and form but now with an extra little HTML table at the bottom of the form with some data I need to get at.
I've so far managed to sort the login and form post using the WebClient class. I've used fiddler (and firebug) to check the POST field values that are being sent when completing the form normally using a browser. I can successfully get a response from the POST request with the data table in question appearing below the form as expected. The problem however is that although the table is populated with data it is populated with data I don't expect. The data that appears is if I completed the form in a browser as normal but with one particular parameter (a drop down list) set to a different value than I'm passing in my POST request to the server. I've confirmed using fiddler and firebug that I'm passing exactly the same POST parameters that are sent as normal using a web browser human completed form. I'm now totally stuck as to why this one parameter is not being 'taken into consideration' by the server?
The one difference is that this particular control is a select list and it performs a page reload or 'postback' when changed. However this doesn't seem to do anything apart from change some other select lists content later in the form.
I guess I'm asking is there anything else I'm missing that would cause this? I'm totally tearing my hair out on this one. Can anyone help? I've posted the code below (with addresses and parameters blanked out for privacy).
// a place to store the html
string responseBody = "";
// create out web client to handle the request
using (WebClient webClient = new WebClient())
{
// space to store responses from the remote site
byte[] responseBytes;
// site uses basic authentication over HTTPS so we'll need to login
CredentialCache credentials = new CredentialCache();
credentials.Add(new Uri(Url), "Basic", new NetworkCredential(Username, Password));
// set the credentials in the web client
webClient.Credentials = credentials;
// a place for __VIEWSTATE
string viewState = "";
// try and get __VIEWSTATE from the web site
try
{
responseBytes = webClient.DownloadData(Url);
viewState = GetHtmlInputValue(Encoding.UTF8.GetString(responseBytes), "__VIEWSTATE");
}
catch (Exception e)
{
bool cancel = false;
ComponentMetaData.FireError(10, "Read web page data", "Error whilst trying to get __VIEWSTATE from web page: " + e.Message, "", 0, out cancel);
}
// add our POST parameters (don't forget the __VIEWSTATE or it won't work as its an ASP.NET web page)
NameValueCollection requestParameters = new NameValueCollection();
// add ASP.NET fields
requestParameters.Add("__EVENTTARGET", __EVENTTARGET);
requestParameters.Add("__EVENTARGUMENT", __EVENTARGUMENT);
requestParameters.Add("__LASTFOCUS", __LASTFOCUS);
// add __VIEWSTATE
requestParameters.Add("__VIEWSTATE", viewState);
// all other form parameters
requestParameters.Add("btnSubmit", btnSubmit);
/* I've hidden the rest of the parameters hidden for privacy just in case */
// see if we can connect and get data
try
{
// set content type
webClient.Headers.Clear();
webClient.Headers.Add("Content-Type", "application/x-www-form-urlencoded");
// 'POST' the form data using web client and hope we get a response
responseBytes = webClient.UploadValues(Url, "POST", requestParameters);
// transform the response to a string
responseBody = Encoding.UTF8.GetString(responseBytes);
}
catch (Exception e)
{
bool cancel = false;
ComponentMetaData.FireError(10, "Read web page data", "Error whilst trying to connect to web page: " + e.Message, "", 0, out cancel);
}
}
Please ignore the 'ComponentMetaData' references as this is part of SSIS script source.
Any ideas or help will be greatly appreciated - cheers!
RE: thanks for the quick responses, all I can say to those comments is...
There's the normal ASP session cookie but there's no values in the cookie (apart from the session ID of course), I figured as the site is using basic authentication not forms authentication I could just ignore the cookie - and as I'm getting into the site and getting data returned this was ok. I guess it's worth a try but I'll have to just alter the code to use the WebRequest class method instead...
As for the select list javascript, no there's no javascript changing the value of the select list after page load. The only javascript on the select list is an onchange event to do a 'postback' which only seems to change some other select lists on the form that are empty anyway in the final POST. Note I'm including all the POST parameters when generating the POST request even if they're empty and I'm also including all the 'web forms' special fields such as __VIEWSTATE, __EVENTTARGET etc...
I'm no expert in web forms (MVC man myself) but is there anything else that the web forms 'engine' is expecting? I've sent 1 header for the 'Content-Type' of 'application/x-www-form-urlencoded' but I've tried setting others such as copying the 'User-Agent' header from the original POST but this ends up with me getting a 500 error from the server, not sure why that would happen??
Here's the code for the 'GetHtmlInputValue' its a bit simple/basic and could be done better but:-
private string GetHtmlInputValue(string html, string inputID)
{
string valueDelimiter = "value=\"";
int namePosition = html.IndexOf(inputID);
int valuePosition = html.IndexOf(valueDelimiter, namePosition);
int startPosition = valuePosition + valueDelimiter.Length;
int endPosition = html.IndexOf("\"", startPosition);
return html.Substring(startPosition, endPosition - startPosition);
}

If I understand you correctly, then selecting an item in the dropdown will cause a POST to be performed, and the server alters the available options in another part of the form. The server will then include the current value of the dropdown in the __VIEWSTATE field value.
When you perform the scraping, you should make sure that the __VIEWSTATE contains the desired value for the dropdown. To investigate further, try to decode the viewstate from the server and see which values are sent back.

Post request getting duplicated after server error

When a request is posted with large data , eventually it gets cancelled with an error
Error: Sys.WebForms.PageRequestManagerServerErrorException: An unknown error occurred while processing the request on the server. The status code returned from the server was: 0
But after this error I am getting doubled results, like request was duplicated,
IAsyncResult res = delCreateReport.BeginInvoke(null, null);
Response.BufferOutput = true;//This property should be set to true to avoid some view state and response exceptions
while (res.IsCompleted == false)
{
Response.Write(" ");
Thread.Sleep(5000);
Response.Output.Flush();
}
Response.Clear();
delCreateReport.EndInvoke(res);
This is the content of the code, here we are using a delegate function for ASYNC trasfer of some data to a 3rd party application, for small data sets it excecutes well but when data is large , and processing time is around 5 minutes , the post request is getting cancelled with the above stated error,but the 3rd party application is listing duplicated data,Using internet explorer no duplication is observed but parser error is there for all, What could be the reaseon for this, I tried avoiding response.write() and update panels but the result is the same. this happens only in the production server its working fine in local while Debugging.Thanks in advance
Edit
Large data here means a greater date range or larger filter conditions for the data transfer, (for eg july 1 - 5 is a small data range july 1 - november 1) is large data, The data here is not data from page, it is fetched from our db and transfered to 3rd party app,
I dont know whether view state have significant role, and another important thing noticed here is this exception is thrown while request responds, ie after the operation is completed , No sign of duplication is found when IE is used but chrome duplicates the data, but both of them produce the error.