How to send an HTTP request without using curl?
We are using JWT validation. For some reasons, when testing on staging, we got 401 error:
1[GIN] 2022/05/20 - 14:20:57 | 401 | 2.588128ms | 127.0.0.1 | POST "/v1/endpoint"
After looking at the source code, we need to set the operation_debug to true to see what caused that error:
12022/05/20 08:31:26 KRAKEND ERROR: [ENDPOINT: /v1/endpoint][JWTValidator] Unable to validate the token: should have a JSON content type for JWKS endpoint
The thing is when testing locally or use port forwarding we see that the
Content-Type is set correctly:
1$ http get localhost:50050/.well-known/jwks.json 2HTTP/1.1 200 OK 3Content-Length: 419 4Content-Type: application/json 5Date: Fri, 20 May 2022 08:54:56 GMT
So, what could be the reason?
After ssh to that pod,
I realized that
nc, … is not installed. And I don’t have permission to do that.
I was wondering if I can send an HTTP request without using any external tool?
Reading Redirections section in the Bash manual, I saw this:
If host is a valid hostname or Internet address, and port is an integer port number or service name, Bash attempts to open the corresponding TCP socket.
So, looks like I can use this Bash’s feature to open a TCP socket to the target host.
First, we need to open a file descriptor for reading and writing on the specified TCP socket:
1$ exec 3<>/dev/tcp/s-auth/50050
Then send an HTTP request to that socket:
1$ echo -e "GET /.well-known/jwks.json HTTP/1.1\nHost: s-auth\nConnection: close\n\n" >&3
You can see this request header by using
1$ curl -v localhost:50050/.well-known/jwks.json 2* Trying ::1:50050... 3* Connected to localhost (::1) port 50050 (#0) 4> GET /.well-known/jwks.json HTTP/1.1 5> Host: localhost:50050 6> User-Agent: curl/7.77.0 7> Accept: */*
And read the response:
1$ cat <&3 2HTTP/1.1 502 Bad Gateway 3content-length: 87 4content-type: text/plain 5date: Fri, 20 May 2022 09:33:33 GMT 6server: envoy 7x-envoy-upstream-service-time: 13 8 9upstream connect error or disconnect/reset before headers. reset reason: protocol error
I will write another blog post to troubleshoot this error.
Tags: bash http
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