Cannot query AWS API Gateway using API Key and CORs - amazon-web-services

I'm almost complete with a new web app, however, I'm getting a 403 error from AWS's API Gateway due to a CORs issue.
I'm creating a Vue app and using Vue's axios library. CORs is enabled and the request works with API Key Required option turned off in AWS's API Gateway by sending the following:
axios
.get('My-URL-Endpoint',{headers: {})
.then(response => (this.passports = response.data ));
When I turn on API Key Required functionality inside AWS's API Gateway. It works when I use Postman along with including x-api-key: My-API-Key. However, using Vue's axios it does not work and returns error 403:
axios
.get('My-URL-Endpoint', {headers: {
'x-api-key': 'My-API-Key'
}})
.then(response => (this.passports = response.data ));
My first instinct is that the problem is related to how Axios is sending the request through the browser. From what I can gather it looks like the pre-flight check is failing because I am receiving the following error within the browser:
Access to XMLHttpRequest at 'My-URL' from origin 'http://localhost:8080' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.
Sure enough it looks like there is no access-control-allow-origin key in the response. So I added access-control-allow-origin to the response of the 403 message and got a new error "It does not have HTTP ok status"
I've been trying nearly everything to get this to work! I came across stackoverflow answer where it seems like the person was suggesting that API Key Required Key functionality can't work with CORs. This kind of seemed like that cannot be true. It would be a pretty crippling restriction.
So my question is how to get the browser's pre-flight check to work along with CORs and API Key capability inside AWS's API Gateway?
Thank you!

If you have enabled cors on your api gateway, the next place to look is the application code such as lambda. Make sure the Lambda is returning the correct cross origin headers in both successful and failure scenarios.
First of all you can check if the request is reaching the lambda from the cloud watch logs. Another way to check this is to temporarily point the Api gateway target to the Mock end point.
If the mock endpoint works, then the problem is the application code. otherwise the problem is in your api gateway end point.
Also note that any headers you use should be white listed in the Access-Control-Allow-headers section when you enable to cors for your method/resource.

Related

AWS Amplify/Lambda/ApiGateway - CORS headers in F12 Network tab does not equal API Gateway Config

I have a site on AWS Amplify that is making an API call to an API Gateway Lambda integration. After strugglebussing with CORS errors for quite a while, I got it working but my headers arent what I expect.
Below is my API gatweway config: I have two allow-origin values and only GET, POST, OPTIONS methods being allowed.
After applying these settings, when I look in the browser f12 network panel when running these API calls through the website, I see that the access-control-allow-headers, access-control-allow-methods, and access-control-allow-origin are set to values that I have not assigned in my config:
So on to the question - Are the response header results normal? I expected to see the headers and http methods I allowed/exposed in the browser api calls and I'm seeing completely different values. I dont know if this is normal.
Thank you!
check your code if you are not exposing all methods in CORS. e.g. if it is on node js / express then below snippet can cause that problem. you can always limit those controls here. If I'm not wrong then your code overrides your gateway configurations.
// Enable CORS for all methods
app.use(function (req, res, next) {
res.header("Access-Control-Allow-Origin", "*");
res.header("Access-Control-Allow-Headers", "*");
next();
});

Configuring OPTIONS method in API Gateway to return statusCode 200

I have a non-simple cross-origin HTTP request to my POST method in API Gateway.
I have set up CORS support as per : https://docs.aws.amazon.com/apigateway/latest/developerguide/how-to-cors.html
The POST request succeeds from Postman/AWS console but fails from a local development server where the origin is of type localhost.
After browsing through many answers and trying to debug i have concluded that all the required headers are present on the integration response of both POST and OPTIONS. However when making a call to OPTIONS from postman i see that it returns 500 Internal server error. This looks like a configuration issue with OPTIONS. How do i fix it? I don't have a serverless yaml, the gateway has been configured manually. Any way of resolving this via the console ?

Ember app has been blocked by CORS policy

I was trying to use my api and I have a function on ember app to login but when the login action is trigerred I receive a message below. What is the reason I am receiving this error?
login:1 Access to fetch at 'https://app-dev.some-url.com.au/api/login' from origin
'http://localhost:4099' has been blocked by CORS policy: Response to preflight request doesn't
pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested
resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch
the resource with CORS disabled.
Your API server isn’t configured to accept requests that come from a web application on another origin. Some options:
Configure your API to serve the Access-Control-Allow-Origin header
on the OPTIONS request that the browser makes to test this. It
could be Access-Control-Allow-Origin: * if you’re lazy or can’t
know in advance what origins people will be coming from. It’s hard
to be more specific about this without knowing details of your API.
Use Ember CLI’s API
proxying
feature to bypass the need for CORS. This is for development mode
only, though. You’d need a similar solution in production where
Ember CLI’s development server isn’t present.

API Gateway HTTP API CORS

I am using the new API Gateway HTTP which during the configuration enables you to add CORS. So I have set the Access-Control-Allow-Origin Header with the setting *.
However when I make a request using Postman I do not see that header and this i causing my VueJS Axios request to fail.
I previously used a Lambda Proxy Integration and did the following in my Lambda
"headers": {
"Access-Control-Allow-Origin": "*"
}
However the new HTTP API just does not seem to implement CORS. Maybe I am missing something simple.
--EDITS--
So I have continue to find an answer and came across a blog post from the guys at Serverless who set the following
It’ll ensure following headers:
Access-Control-Allow-Origin: *
Access-Control-Allow-Headers:
Content-Type, X-Amz-Date, Authorization, X-Api-Key, X-Amz-Security-Token, X-Amz-User-Agent
Access-Control-Allow-Methods:
OPTIONS, and all the methods defined in your routes (GET, POST, etc.)
I have tried these and redeployed and still only get the standard headers
Thanks
For anyone using HTTP API and the proxy route ANY /{proxy+}
You will need to explicitly define your route methods in order for CORS to work.
Wish this was more explicit in the AWS Docs for Configuring CORS for an HTTP API
Was on a 2 hour call with AWS Support and they looped in one of their senior HTTP API developers, who made this recommendation.
Hopefully this post can save some people some time and effort.
If you have a JWT authorizer and your route accepts ANY requests, your authorizer will reject the OPTIONS request as it doesn't contain an Authorization/Bearer token. To resolve this issue, you need to explicitly point your route to the HTTP request/method you need. E.g. POST
In that case, your authorizer will ignore the OPTIONS request without a JWT and proceed with the required request.
(This is answer just for AWS HTTP api gateway/AWS api gateway v2).
I have met the same problem and I asked the AWS support finally. The tricky thing is actually CORS had been already working after we configured it, but I just didn't get how to test it (it's different from AWS REST API ), when test we need to specify the Origin(should be same with your setting:Access-Control-Allow-Origin in cors, like: http://example.com) and the Request method.
For example:
curl -v -X GET https://www.xxx.yy/foo/bar/ -H 'Origin:http://example.com' -H 'Access-Control-Request-Method: GET'
Then it would return the CORS header you had set in response header:
access-control-allow-origin, access-control-allow-methods, access-control-allow-headers, etc.
I just hope this can save time for who met the similar problem.
By the way, I hope AWS can update this test way to offical Document(it's not very useful, but most of people must be saw it before find real answer):
https://docs.aws.amazon.com/apigateway/latest/developerguide/http-api-cors.html
My issue was that I was sending this headers :
Access-Control-Allow-Origin
Access-Control-Allow-Methods
Access-Control-Allow-Credentials
From the web request and it was messing with the Access-Control-Allow-Headers. I removed them and it's fine now.
To debug CORS issue with AWS HTTP API, try to put a * in each field of the CORS configuration in the AWS Console and reconfigure each field one by one.
So even though i was getting cors headers in my post call, browsers were still failing,,
My solution was
explicitly create an OPTIONS route with same path {proxy+}
attach same lambda integration to it
have the lambda function return early with success headers
if (method === 'OPTIONS') {
return {
headers: { 'Access-Control-Allow-Origin': '*' },
statusCode: 200
}
}
tldr; x-api-key
It took some searching and trial and error, but I got CORS working for API Gateway HTTP API. For the very basic GET request from a jQuery ajax call here is what I had to do:
AWS Console CORS settings, needed Access-Control-Allow-Headers: x-api-key
Then, in my ajax call, I had to send a dummy x-api-key (I did not configure one, so not sure why it wants it.):
$.ajax ({
url: 'https://xxxxxxx.execute-api.us-east-1.amazonaws.com/prod/stuff/',
crossDomain: true,
method: 'GET',
headers: {
"accept": "application/json",
"X-Api-Key":"blablablalla"
},
success:function(data){
doStuff(data);
},
error: function(){
alert('error');
}
})
You may need additional configuration depending on your situation, but the x-api-key was what I narrowed down as the oddest undocumented requirement.

AWS API Gateway ERR_CONTENT_DECODING_FAILED in browser

In my use case, API Gateway serves as an HTTP proxy, using default settings following official tutorial.
It's tested working in test console or via curl. But if I access the link in browser or make an AJAX call, I'll get ERR_CONTENT_DECODING_FAILED.
It seems that API Gateway corrupt the content. Related issue.
Is there a way to forbid API Gateway changing my content? I set Content Handling to passthrough, but clearly it's changing my content.
Add a static integration request header Accept-Encoding with value 'identity', so that AWS won't tamper your request.