"Unable to load /proxy/?http://localhost Statu 404

[JoseSanchez]

Hello everyone,

I am getting the following error message

"Unable to load /proxy/?http://localhost/FindNextVALUENumber/api/value status: 404"

when running this sample:

https://developers.arcgis.com/javascript/3/jssamples/data_requestJson.html

When I pass these URLs, the first one works fine but the second one fails

url = "http://localhost:59297/api/value";   <ç========WORKS FINE – it is the Visual Studio 2012 proejct

Or

url = "http://localhost/FindNextVALUENumber/api/value"; <ç==== FAILS – runs from IIS

The second URL is the IIS Application pointing to the same folder.

I am using the proxy server from this sample: https://github.com/Esri/resource-proxy

I tested both url and they work fine with the proxy:

http://localhost/proxy/proxy.ashx?http://localhost:59297/api/value

 http://localhost/proxy/proxy.ashx? http://localhost/FindNextVALUENumber/api/value

Here is the proxy.config file

 <ProxyConfig allowedReferers="*"   mustMatch="true">

   <serverUrls>

     <serverUrl url="http://localhost:61004"

                 matchAll="true"/>

     <serverUrl url="http://localhost:59297"

               matchAll="true"/>

     <serverUrl url="http://localhost"

                   matchAll="true"/>

   </serverUrls>

</ProxyConfig>

My code:

            esriConfig.defaults.io.proxyUrl = "/proxy/";

           var url = "http://localhost:59297/api/value";

           url = "http://localhost/FindNextVALUENumber/api/value";

           dom.byId("url").value = url;

           dom.byId("content").value = "";

           //handle the Go button's click event

           on(dom.byId("submitRequest"), "click", getContent);

           var serviceDescriptionStr = "";

           function getContent() {

               var result = "";

               var contentDiv = dom.byId("content");

               contentDiv.value = "";

               domClass.remove(contentDiv, "failure");

               dom.byId("status").innerHTML = "Downloading...";

               var requestHandle = esriRequest({

                    "url": url,

                   handleAs: "json"

                 });

               requestHandle.then(

                                 function (response) {

                                     console.log("Data: ", response);

                                     dojoJson.toJsonIndentStr = " ";

                                     console.log("Success: ", response);

                                 },

                                 function (error) {

                                      console.log("Error: ", error.message);

                                     alert(error.message);

                                });

            }

[JoseSanchez]

Robert,

Typing

http://localhost/proxy/proxy.ashx?http://localhost/FindNextVALUENumber/api/value  

or

http://[mymachine]/proxy/proxy.ashx?http://[mymachine]/FindNextVALUENumber/api/value

Work fine.

 It looks like https://js.arcgis.com is trying to open the link but it can't or it does not allowed.

The error persists pointing directly to my computer name instead of localhost

XMLHttpRequest cannot load http://jsancn-3/proxy/proxy.ashx?http://jsancn-3/FindNextVALUENumber/api/value. Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'null' is therefore not allowed access.

1. Object

2. responseText:""
3. stack:"Error: Unable to load http://jsancn-3/proxy/proxy.ashx?http://jsancn-3/FindNextVALUENumber/api/value status: 0↵ at new n (https://js.arcgis.com/3.18/init.js:111:353)↵   at XMLHttpRequest.f (https://js.arcgis.com/3.18/init.js:142:454)"
4. status:0

[RobertScheitlin__GISP]

Jose,

   This is how I have code in my app that calls a RESTfull web service without that error:

        var requestHandle = esriRequest({
          url: 'my web service url and endpoint',
          content: {
            ppin: ppin,
            f: 'json'
          },
          handleAs: "json",
          timeout: 10000
        },{useProxy: true, usePost: false, disableIdentityLookup: true});

        requestHandle.then(lang.hitch(this, function(taxReportJSON){
        ....‍‍‍‍‍‍‍‍‍‍‍‍

[JoseSanchez]

Hi Robert,

When do I have tdeclare a content part?

content: {
            ppin: ppin,
            f: 'json'
          }

This is my code, let me update it to match yours:

esriConfig.defaults.io.alwaysUseProxy = true;
esriConfig.defaults.io.proxyUrl = "http://jsancn-3/proxy/proxy.ashx";
var url = "http://jsancn-3/FindNextVALUENumber/api/value";

var requestHandle = esriRequest({
                    "url":  url,
                   handleAs: "json"
                    //callbackParamName: "jsoncallback"

                });
                requestHandle.then(requestSucceeded, requestFailed);

[RobertScheitlin__GISP]

Jose,

   If your web service does not take an input parameter then no you do not need the content part

[JoseSanchez]

It works now!

I just created an empty  ASP.Net application, added  html file "HtmlPage2.html", and used the "Internal Web Browser" to run the project. Selecting the HtmlPage2.html as "Set as Start Page" I was able to run it in Visual studio.

I am using URLs with my machine name instead of "localhost.

   var requestHandle = esriRequest({
                    "url":  url,
                   handleAs: "json"
                   

                }, {useProxy: true, usePost: false, disableIdentityLookup: true});

requestHandle.then(requestSucceeded, requestFailed);

[RobertScheitlin__GISP · Accepted solution]

Great, don't forget to mark this as answered.