Capture Examples

Below are some examples using various tools to generate Capture traffic. Since Capture works by configuring a reverse proxy to forward traffic to your API, any tool that allows you to configure where requests are sent can be used.

ℹ️

To make it easier to send traffic to Capture's proxy, a variable is injected into server.command's environment. By default, this variable is OPTIC_PROXY, but can be modified as necessary by setting a value for server.proxy_variable.

ℹ️

By default, Capture's proxy will be listening on localhost:8000. A higher port number may be chosen if 8000 is in use. Alternatively, you can choose a specific port via the --proxy-port CLI option.

Optic

The simplest example is using Optic to send traffic to your API by defining requests directly in your optic.yml file. This is a fine place to start if you have a small surface area to cover or don't have an OpenAPI file yet and want to get one created quickly.

optic.yml

capture:
  openapi.yml:
    server:
      command: npm run start-server
      url: http://localhost:8080 # where your API is expected to be listening once started
    requests:
      send:
        - path: /
        - path: /widgets
        - path: /widgets/create
          method: POST
          data:
            name: widget1

Curl

requests.sh

#!/usr/bin/env sh
curl -s "$OPIC_PROXY"/widgets
 
curl -s -XPOST "$OPTIC_PROXY"/widgets/create \
   -H 'Content-Type: application/json'
   -d '{"name": "widget1"}'

optic.yml

capture:
  openapi.yml:
    server:
      command: npm run start-server
      url: http://localhost:8080
    requests:
      run:
        command: sh ./requests.sh

Hurl

https://hurl.dev (opens in a new tab)

requests.hurl

GET {{OPTIC_PROXY}}/widgets
POST {{OPTIC_PROXY}}/widgets/create
{"name": "widget1"}

optic.yml

capture:
  openapi.yml:
    server:
      command: npm run start-server
      url: http://localhost:8080
    requests:
      run:
        command: hurl ./*.hurl # globbing is supported!
        proxy_variable: HURL_OPTIC_PROXY # hurl only exposes env vars with a HURL_ prefix

HTTPie

https://httpie.io (opens in a new tab)

httpie.sh

#!/usr/bin/env sh
 
# HTTPie doesnt support defining requests in a dedicated file, but we can still script it
 
CMD="http"
OPTS="--ignore-stdin"
 
"$CMD" "$OPTS" "$OPTIC_PROXY"/
"$CMD" "$OPTS" "$OPTIC_PROXY"/widgets
"$CMD" "$OPTS" POST "$OPTIC_PROXY"/widgets/create name=widget1

optic.yml

capture:
  openapi.yml:
    server:
      command: npm run start-server
      url: http://localhost:8080
    requests:
      run:
        command: sh ./httpie.sh

Capturing Test Traffic HAR files/Postman