TL;DR

I can't send HTTP request to local docker container (accessible via 127.0.0.1:4002) through Kong gateway.

Kong Gateway components:

• Service test_service: url=http://127.0.0.1:4002;
• Route test_route: paths[]=/test, name=test_route;

Request to Kong proxy:

$ curl -X GET http://localhost:8000/test{"message":"An invalid response was received from the upstream server","request_id":"9aba1e35ea54222d9fd27c4e2eeea850"}

Long Version

I created a simple Express app that responds to HTTP requests with "Foo" and "Bar", and dockerized it.

Application

index.js:

const express = require('express');const app = express();var port = 4002;app.use("/foo", (req, res) => {    res.send("Foo");});app.use("/bar", (req, res) => {  res.send("Bar");});app.use((req, res) => {  res.send("Test unknown path");});app.listen(port, () => {  console.log(`Foo-bar listening on port ${port}`)})

Dockerfile:

FROM node:lts-alpineWORKDIR /usr/src/appCOPY package*.json ./RUN npm installCOPY . .EXPOSE 4002CMD ["node", "index.js"]

After building and running it, I can send HTTP requests to "localhost:4002" and correctly get the responses.

Example:

$ docker psCONTAINER ID   IMAGE                        COMMAND                  CREATED              STATUS                 PORTS                                             NAMESfce1cc4e7b24   mikyll/test-service:latest   "docker-entrypoint.s…"   About a minute ago   Up About a minute      0.0.0.0:4002->4002/tcp                            nice_blackwell$ curl -X GET http://localhost:4002Test unknown path$ curl -X GET http://localhost:4002/fooFoo$ curl -X GET http://localhost:4002/barBar

Kong Setup

I followed the instructions to setup Kong Gateway on Docker and manage services and routes:

1. I run Kong Gateway container:

curl -Ls https://get.konghq.com/quickstart | bash

2. Tested the connection:

$ curl --head localhost:8001HTTP/1.1 200 OK[...]

3. Created a service:

$ curl -i -s -X POST http://localhost:8001/services --data name=test_service --data url='http://127.0.0.1:4002'HTTP/1.1 201 Created[...]

Service JSON:

{"data":[    {"retries":5,"tls_verify":null,"protocol":"http","port":4002,"updated_at":1700054325,"created_at":1700054325,"connect_timeout":60000,"read_timeout":60000,"client_certificate":null,"host":"127.0.0.1","path":null,"name":"test_service","enabled":true,"tags":null,"write_timeout":60000,"ca_certificates":null,"id":"e79539ca-603b-4237-8abd-6ff07bd73160","tls_verify_depth":null    }  ],"next":null}

4. Created a route:

$ curl -i -X POST http://localhost:8001/services/test_service/routes --data 'paths[]=/test' --data name=test_route

Route JSON:

{"data":[    {"https_redirect_status_code":426,"service":{"id":"e79539ca-603b-4237-8abd-6ff07bd73160"      },"id":"4b04a262-6229-4361-9b2c-88f00b0fe6c2","hosts":null,"path_handling":"v0","updated_at":1700054404,"created_at":1700054404,"preserve_host":false,"headers":null,"methods":null,"sources":null,"destinations":null,"paths":["/test"      ],"snis":null,"name":"test_route","tags":null,"request_buffering":true,"response_buffering":true,"protocols":["http","https"      ],"regex_priority":0,"strip_path":true    }  ],"next":null}

Problem

When I try to send an HTTP request, I get the error "An invalid response was received from the upstream server.":

$ curl -X GET http://localhost:8000/test{"message":"An invalid response was received from the upstream server","request_id":"9aba1e35ea54222d9fd27c4e2eeea850"}

Question

Is my configuration (service/route) wrong? Am I missing some setup step?