RestKit: set expected status codes without using response descriptor - restkit

I need to PUT/POST data to a service. Upon success, the server returns 201/Created (no body). The parameters are (necessarily) a NSDictionary, so no object binding on either side is needed. RKObjectManager.requestWithObject works fine for this, but raises an error it expected a 204 rather than a 201. As far as I can tell, the only place to alter expected status codes is in a matching RKResponseDescriptor. RKResponseDescriptors seem like overkill for a response which has no body, and I'm unsure how to even construct one that works with no body. How can I tell RestKit that a 201 is OK for this POST?
Update
I eventually gave up on trying to do requests that didn't involve any sort of binding (ie, posting a dictionary and receiving a 201 response), and just dropped down to NSURLConnection stuff - it wasn't bad)

On your RKObjectRequestOperation:
operation.HTTPRequestOperation.acceptableStatusCodes = [NSIndexSet indexSetWithIndex:201];

Related

How to use custom error settings for JWT middleware

I have followed the cook books guide to the letter, found here https://echo.labstack.com/cookbook/jwt
But when using the JWT middleware I am having some issues with adding custom error messages. Login works fine, even to the point of not giving details (username & password) that returns a 404.
But when the JWT is missing it returns a 400, I want it to also return a 404.
So in my research I found this, https://forum.labstack.com/t/custom-error-message-in-jwt-middleware/325/3 which lists the following middleware.ErrJWTMissing & middleware.ErrJWTInvalid But is very unclear on how to set these?
I have tried setting them as vars on the router file, like so
var (
ErrJWTInvalid = echo.NewHTTPError(http.StatusTeapot, "test 104")
ErrJWTMissing = echo.NewHTTPError(http.StatusTeapot, "test 103")
)
But the error that sill comes back to me is a 400 and not a 418 (as this is just a test). So what am I doing wrong?
You can change the HTTP code and message this way.
func init() {
middleware.ErrJWTMissing.Code = 401
middleware.ErrJWTMissing.Message = "Unauthorized"
}
First, a point on your statement that you want to return a 400 and also a 404 error - you cannot do this. You're sending one response from the server so it gets exactly one response code. You could send a 207, but we're not really talking about multiple resources here, so don't do that. In my opinion, a 400 error is indeed the correct response for a missing JWT as that constitutes a bad request. A 404 "Not Found" means that the requested resource (the thing on the server side) could not be found. It does not mean that something in the request could not be found.
As for setting your custom error message, you're likely to be out of luck without altering the source code for Echo. That specific response is coming from within the middleware handlers of the package itself (you can see it here). This is mostly abstracted away from you, so without looking at the inner workings of the package, there would be no way to tell where this was coming from, and frankly there's not a lot that you can easily do about it. ErrJWTMissing is indeed the variable that the package uses internally for this error message, but Echo does not appear to provide an exported setter method for you to change this value, so you're stuck with what it is.
If you truly wanted to set a custom error method for this case I think your options would be to:
Write your own middleware to intercept the request before it was handled by Echo's middleware, where you could handle the request however you wanted.
Edit the Echo source to work how you wanted it to work -- specifically, all you would have to do is edit ErrJWTMissing.
Basically, Echo is trying to do you favors by handling all of this middleware processing for you, and it's a lot of work or hackery to un-do that work while still using Echo.

How to inject a header from the errormessage

I've been attempting to inject a custom header for a error response status (and failing).
I have a very simple lambda being used
exports.handler = (event, context, callback) => {
// TODO implement
//callback(null, 'Hello from Lambda');
var error = {
name:"error",
message:"I am a failure",
statusCode: 400
};
error["x-test"] = 'foo';
callback(JSON.stringify(error), null);
};
In the api gateway, I've done the following:
set up CORS to include x-test
responsetemplate = "$input.path('$.errorMessage')"
responseparameter to include:
method.response.header.x-test = integration.response.body.x-test
Also, I have a statusCode mapped using '.*statusCode.*?400.*'
This has turned out empty.
so I decided to take a step back and see what happens if I do:
method.response.header.x-test = integration.response.body
I found that I get the stringified response of errorMessage.
{"x-test":"{\"errorMessage\":\"{\\\"name\\\":\\\"error\\\",\\\"message\\\":\\\"I am a failure\\\",\\\"statusCode\\\":400,\\\"x-test\\\":\\\"foo\\\"}\"}"}
So I decided to change the responsetemplate to force it to json by doing the following:
responsetemplate = "$util.parseJson($input.path('$.errorMessage'))"
and I still get the stringified response:
{"x-test":"{\"errorMessage\":\"{\\\"name\\\":\\\"error\\\",\\\"message\\\":\\\"I am a failure\\\",\\\"statusCode\\\":400,\\\"x-test\\\":\\\"foo\\\"}\"}"}
My guess is that it doesn't transform as expected, but only for the final output.
So how would you take a value and shove it into a header?
Thanks,
Kelly
I think this is more of a design choice regarding the limitation imposed by both Lambda and APIGateway. I will try my best to walk through my thoughts.
First of all, in Lambda, callback(error, result) function can either take an error string as first argument, or an object as result response. If you want to pass along a simple error message, you could definitely just do that. However, in your case, as you tried to pass along an entire error object, choosing the second option is clearly a better solution (in contrast to stringifying an object and parse it into object again). As a result, the final line of your Lambda function should be:
callback(null, error);
Yes, in this case, if you test your function in Lambda, the output result will no longer be red and flag it as an error, but this won't matter as you can format your headers and response in APIGateway.
Now you need to set things up in APIGateway, in which you need to make use of the object passed by Lambda.
It's actually rather easy to use method execution interface to configure headers.
In Method Response, you need to add the headers you want to include in the response for a specific status code, which in your case is x-test. (If you want the API to return different status codes, you can also configure that in this panel.)
Then go to Integration Response, under the same status code, you will see the added header available. According to this documentation from AWS, you can use integration.response.body.JSONPath_EXPRESSION to assign the header value (this is another reason that you should return object rather than string in Lambda, as there is no formal API to parse object from string at this stage). This time, as your Lambda is passing an object, the value of x-test header is:
integration.response.body['x-test']
Now your API should have the proper header included.
NOTE: In order to set up different status code in APIGateway, you should leave some distinguishable data fields (your statusCode: 400 should work perfectly) in you response body, so you can use RegEx to match those fields to a specific status code.
So... above doesn't work with success message. I found this blog though talking about error handling design pattern. Apparently what they suggest is only mapping status code when there is an error, in which case no body should be passed (only the errorMessage), as browser won't care about response body for a status code other than 200 anyway.
I guess after all, it is impossible to customize both status code and header at the same time with Lambda passing an object to APIGateway?
This is due to the fact that you are stringifying the error object coming from your Lambda function. API Gateway attempts to resolve the JSON-Path expression and can't evaluate "x-test" in a string. If you return an object instead of a string, this should work.
You may want to consider using proxy integrations which allow you to control the headers and status directly from your Lambda function.
Update: I've written a blog post on this topic with sample code # https://rpgreen.wordpress.com/2017/01/25/how-to-send-response-headers-for-aws-lambda-function-exceptions-in-api-gateway/

Google Api Ruby Client to return the actual HTTP response, not the helper object

Is there an easy way to ask the google api ruby client to just give you back the stock HTTP response, rather than to perform the lovely, but slightly limiting translation into one of their ruby representable objects?
e.g.
response = Gmail.client.get_user_message("me", id)
=> #<Google::Apis::GmailV1::Message
response = Gmail.client.list_user_messages("me")
=> #<Google::Apis::GmailV1::ListMessagesResponse
but
response = Gmail.client.delete_user_message("me", id)
=>nil #successfully deleted
Now that's all fine and dandy, except that sometimes I just want to know what sort of response is going to come back. i.e. an HTTP response with maybe some JSON in the body. And then I'll worry about what I do with it...
I can take the response and use the
response.to_json
to get the body of the json that would have come back (though I still won't have the response code, and I need to KNOW that it's one of those objects first).
The client library is definitely getting that, it's just converting it into these objects before it lets me see it. And if I don't know that it's a google object (and not nil) I can't run that to_json consistently....
Any ideas other than second guess what google is going to send me back?
(I should note that this has come about when trying to move a library from dealing with their 0.8 api to their 0.9 api, so call me a cynic if you must but my faith that google won't make breaking changes to those objects returned is at a low ebb...
As far as I know, it is possible to ask the server to send only the fields you really need and get a partial response instead of the default full response as mentioned in Performance Tips.
However, I suggest that you please check the documentation for the specific API you are using to see if the field you're looking for is currently supported. For the Gmail API, you may go through Working with partial resources.
Here are the two types of partial requests that you can use:
Partial response: A request where you specify which fields to include in the response (use the fields request parameter).
Patch: An update request where you send only the fields you want to change (use the PATCH HTTP verb).
Hope that helps!

Response data is changed when calling web api using ajax request

I have a web api which is returning a list(each item consists of bit values).
But when I see response from client side in console, I found that the bit value is changed.
For example if I have 36028797018963968 bit value in database then it is changed to 36028797018963970.
This is happening only for this bit value. In a list of 5 values only the above mentioned value is changing. The remaining are coming fine.
I have never seen this type of behaviour before, so I am not sure what else I should be posting here. Ask me if you need anything else.
There is no limitation for integer values in Json. But Javascript has boundaries.
JSON transfer of bigint: 12000000000002539 is converted to 12000000000002540?

Custom http codes

Could I use custom HTTP codes?
I want to use these codes as response for AJAX requests.
Example:
220 - will be correspond to status that some item was created successfully
420 - will be correspond to status that some validations errors were occurred
Each response will be has json string.
You can define extension codes, but it only makes sense if you want to standardize something; in which case you need to write a spec, and get the status code registered (see http://greenbytes.de/tech/webdav/draft-ietf-httpbis-p2-semantics-12.html#rfc.section.4.1).
If this is just between your server and your client, simply put the additional information into the response body and use a more generic status code.
That being said -- what you called "420" is already defined as "422 Unprocessable Entity".
Using your server side language of choice you can send headers to the browser with the relevant HTTP code and message.

Resources