Can we add Json object to RequestHeader of HTTP GET method - rest

I am developing a new REST-full webservice for our application,I wanted to send the reqest data in requestHeader instead of sending as query param, as my request data is large.
I have My jquery code like below to add json to the request header and call the REST service GET method.
$.ajax({
beforeSend: function(req) {
req.setRequestHeader("test", "{name:mouli, id:918}");},
type : "GET",
data :'',
dataType : "jsonp",
url : 'http://localhost:29801/RestFulJSONExample/rest/jobdesc?callback=?',
success : function(data) {
alert("invoked");
}
});
});
And my GET method in my REST service is like
#GET
#Produces("application/javascript")
public JSONWithPadding getJobDescription(#Context HttpHeaders headers) {
List<String> requestHeader = headers.getRequestHeader("test");
//some logic here.
}
i could able to get the JSON object from the request header which i have added in the jquery request.
My question is ..
Can i follow this approach? is it secure and safe?
If not please tell me the other way?

What appears at the right side of the ":" in a header is mostly free. You have to take into account character set restriction in HTTP, and possible carriage returns in the JSON value (you know, headers of more than one line have a specific syntax). If your JSON examples are relatively simple, then I see no problem in that. It is just another way of organizing the actual value of a header line.

Related

Empty MultipartFile[] when sending files from Vue to SpringBoot controller

I'm doing a program that will help me to make monthly reports and I stuck at uploading photos which I need for one kind of the reports. For some reason, it doesn't get an array in the controller.
I use Springboot RestController at the backend and Vue with BootstrapVue and vue-resource on the other side.
index.html (BootstrapVue):
<b-form-file
v-model="photos"
accept="image/*"
multiple
placeholder="..."
></b-form-file>
<b-button #click="uploadPhotos">Upload</b-button>
inside vuemain.js:
data: {
photos: null,
},
methods: {
uploadPhotos(){
var formData = new FormData();
formData.append("photos", this.photos);
this.$http.post('reports/photo', formData).then(result => {
...
})
}, ...
inside Controller:
#PostMapping("/photo")
public void addPhoto(#RequestParam("photos") MultipartFile[] photo) {
System.out.println(photo.length); // shows 0
}
what I see inside Params at browser:
XHRPOSThttp://localhost:8080/reports-maker/reports/photo
[HTTP/1.1 500 326ms]
Request payload
-----------------------------4469196632041005505545240657
Content-Disposition: form-data; name="photos"
[object File],[object File],[object File],[object File]
-----------------------------4469196632041005505545240657--
​
So for some reason at this point #RequestParam("photos") MultipartFile[] photo it's empty array. But if I change it to just one photo like this: #RequestParam("photos") MultipartFile photo and send one from js: formData.append("photos", this.photos[0]); everything works nicely and photo gets uploaded to the server.
It's my first experience with Vue and to be honest I don't want to go deep into JS learning, so probably there is some silly mistake somewhere. Any way I can use a loop in JS method to upload them one by one, but that would be so ugly. I hope there is a better way to do it (without any additional JS libraries of course).
If you use axios then you should add header
var headers = {
'Content-Type': 'multipart/form-data',
};
axios.post(
'reports/photo',
formData,
{
headers: headers,
}
)
...
to be able send files to the server.
I agree, sending files in separate requests one by one is very "ugly", but I also don't like the idea of not using the mapping resources of Spring Boot, having to send all files with different names (seems disorganized) and having to work with MultipartHttpServletRequest, but there is a simple solution for this: Ian's answer to this question (not realy related to Vue.js, but useful) worked for me:
In order for Spring to map items in a request to a list, you need to provide the same name (in the FormData.append calls) for each item when appending to the form data. This allows Spring to effectively see the request as name=value1&name=value2&name=value3 (but obviously in the form of form data). When Spring sees the same key ("name") multiple times, it can map the values into a collection.
In your .vue file, append the photos with the same name:
for (let i = 0; i < this.photos.length; i++) {
formData.append("photos", this.photos[i]);
}
And in your Controller:
#PostMapping("/photo")
public void addPhoto(#RequestParam("photos") MultipartFile[] photo) {
System.out.println(photo.length); // Should be greater than 0 now
}
Note:
I used Vue Axios to consume my API and manually added the Content-Type: multipart/form-data header. Make sure its in your request header list.
I found an acceptable solution here https://stackoverflow.com/a/33921749/11508625 Rossi Robinsion's code works nicely. At least it looks better than sending files in separate requests one by one.
The answer is based on using getFileNames() which helps to iterate on files inside a request even if they are not in the array.

Getting a specific data from HTTP body response

I am sending some data to my api by post and when it successfully submitted, it will return some data and I want to access the response data.
This is what I've got from my component :
this.http.post(this.restProvider.restApiUrl+'saveDraft', draftData, options)
.subscribe(data => {
console.log(data["_body"]);
}, error => {
console.log("Oooops!");
});
The console.log(data["_body"]); will resulting this data :
{"status":"ok","data_id":"2","statusMsg":"Saved as draft"}
What I'm trying to do now is to access the value of data_id but I'm not really sure how to get it inside my component. I thought it can be accessed by something like data["_body"]["data_id"]
I think data is an object. Try this:
console.log(data._body.data_id);
console.log(data["_body"].data_id);
Finally, I solved the issue by changing the console.log(data["_body"]); to console.log(data.json().data_id);
I refer to this discussion Angular 2: How to access an HTTP response body? and tried to apply the JSON and it works.

upload a file in SAPUI5 and send to Gateway server

I am having difficulties trying to figure out a way to send uploaded file and send it to a Gateway server. I am using the basic FileUploader control.
***<u:FileUploader
id="fileUploader"
name="myFileUpload"
uploadUrl="upload/"
width="400px"
tooltip="Upload your file to the local server"
uploadComplete="handleUploadComplete"/>
<Button
text="Upload File"
press="handleUploadPress"/>***
And in the controller I have the following event handler
***handleUploadPress: function(oEvent) {
var oFileUploader = this.getView().byId("fileUploader");
oFileUploader.upload();
}***
What code should I add after oFileUploader.upload() to have an xstring that I can pass to my attachment property of my OData srvice
Thank you
The first thing to do is to make sure that you have a gateway service that is able to handle media types and streams. To set this up you need to set the entity that is handling the file content as a media type and get the logic in place that deals with streams (CREATE_STREAM). You can find more information on how to do this in this SCN blog.
In your UI5 application, you will have to set the URL of the upload control to e.g. /sap/opu/odata/sap/AWESOME_SERVICE/Customers('0000123456')/$value so that the file is handled by the CREATE_STREAM method that you just implemented.
When the upload is eventually taking place, you need to deal with two header parameters; the slug and the CSRF token. The slug header should be set to e.g. the filename, while the CSRF token needs to be retrieved using a pre-flight request. To set the headers, you could use something like this:
oFileUploader.addHeaderParameter(new FileUploaderParameter({
name: "x-csrf-token",
value: _csrfToken
}));
The slug header parameter could be set in a similar way and should contain something that identifies the file, e.g. filename or id.
To determine the CSRF token, you could do something like this:
var _csrfToken = "";
jQuery.ajax({
url: "/sap/opu/odata/sap/AWESOME_SERVICE",
headers: {
"X-CSRF-Token": "Fetch",
"X-Requested-With": "XMLHttpRequest",
"DataServiceVersion": "2.0"
},
type: "GET",
contentType: "application/json",
dataType: 'json',
success: function(data, textStatus, jqXHR) {
_csrfToken = jqXHR.getResponseHeader('x-csrf-token');
}
});
With the right header parameters in place, sending the file to a properly configured gateway entity should do the trick to get your file uploaded.

Web API calls with RestSharp - prepends application/json to body causing null parameter on action

I have a Web API service that I'm trying to access via the console using RestSharp. My RestSharp code looks like this:
RestClient client = new RestClient(baseUrlString);
RestRequest request = new RestRequest("controllername/actionname");
request.RequestFormat = DataFormat.Json;
ProcessQuestion model = new ProcessQuestion()
{
Id = "123456",
InstanceId = "123",
UniqueId = "bfb16a18-d0d6-46ab-a5b3-2f0ebbfe8626",
PostedAnswer = new Dictionary<string, string>() { { "question_7907_1", "selected" }, { "question_7907_2", "selected" } }
};
request.AddBody(model);
var response = client.Execute(request)
My Web API action takes a model that has the same parameters as the above model. When the call executes, the binding fails and the parameter is null. I suspect this is due to the RestRequest.AddBody method prepending application/json to the body value as shown below:
{application/json={"Id":"123456","InstanceId":"123","UniqueId":"bfb16a18-d0d6-46ab-a5b3-2f0ebbfe8626","PostedAnswer":{"question_7907_1":"selected","question_7907_2":"selected"}}}
If I post using Fiddler the body binds to the model properly. Below is the body value I provided in Fiddler:
{'Id':'123456','InstanceId':'123','Uniqueid':'bfb16a18-d0d6-46ab-a5b3-2f0ebbfe8626','PostedAnswer':{'question_7907_1':'selected','question_7907_2':'selected'}}
Note that the body value in fiddler is the same with the exception of prepending the application/json key.
Also to note: I've tried what seems like everything...I've separated the parameters out in the action, used FromBody and FromUri attributes, tried custom DictionaryModelBinder's, tried custom ValueBinders, tried changing the way I'm using RestSharp (AddParameter with a RequestBody parameter, AddObject, different URL styles, etc.).
Has anyone else encountered this, and if so, did you solve it? I chose Web API for this service with hopes the model binding would work as it does in MVC, but I'm seeing that isn't the case.
Thanks
EDIT (resolved):
RestSharp automatically uses the JsonSerializer for objects passed in the AddBody method. I figured I was missing something simple, and indeed I was... Adding the Method.Post parameter to the RestRequest instantiation solved the problem.
Specify the method when creating the request:
RestRequest request = new RestRequest("controllername/actionname", Method.POST);
Not sure what the default serializer is for body - you can try making it explicit:
request.AddBody(request.JsonSerializer.Serialize(model));
I'm not sure where the 'application/json' is coming from - that's the Content-Type header you should be sending with your request, definitely not part of the body. So do this instead:
request.AddHeader("Content-type", "application/json; charset=utf-8");
If this doesn't help, try making your code as similar to the example on their site as possible. Try removing complexity (even if it means changing the required functionality) - get it to a point when it works and build additional functionality on that.
http://restsharp.org/

How to make ajax call in extjs and display the json value inside div?

I am new in extjs. I need to know how to make ajax call in extjs and display the json values in inside div. I don't need to use grid..
In ExtJS, you will have to use the Ext.Ajax class to make ajax calls to a remote server. Following is a typical code showing how to do it:
Ext.Ajax.request({
url: 'ajax_demo/sample.json',
success: function(response, opts) {
var obj = Ext.decode(response.responseText);
console.dir(obj);
},
failure: function(response, opts) {
console.log('server-side failure with status code ' + response.status);
}
});
In case of HTTP success (200 OK), the control will go inside the success callback and the first things that we have to do is decode the response.responseText which will give you the JSON response coming from the back-end data source.
Once you have code the JSON, you are free to format it and add it to any element (say to a div in your case). In case you want to format the JSON data nicely before adding, you may do that using Template/XTemplate.
I have used something like this.
$.getJSON('somepathtoserver/somefile.php?callback?', variable,function(res){
});
In the somefile.php, I have a callback function that processes and return the value to the js function.
like this:
{
echo $_GET['callback']. '(' . "{'someValue' : $calculatedVariable}" . ')';
}
This is tricky, but very useful when trying to ajax from one server to a different server, which is the reason I would use JSON here and not just a straight AJAX request.