comcar_api.sh

#!/bin/bash

# Setup required variables
host="d51ts.vehicles.api.comcar.co.uk"
path="/v0/makes/lamborghini/models/aventador/vehicles/"
api_key="cheesecake"
api_secret="fish"
nonce="making something up here"
dev_ip="192.168.0.24"
timestamp=$(date -u +%s)

# concat variables for ease of use
hmac_key="$api_key$api_secret$nonce$timestamp$dev_ip"
# get the sha256 hash of the concatted vbls
# only return frist 64 characters as the rest of the output is unnecessary
hmac=$( echo -n "$hmac_key" | sha256sum | head -c 64  )

# make the request, adding the necessary headers
# k flag means insecure mode ie ignore invalid/self-signed ssl certificate 
# i flag means include headers in output, don't add if you want to pretty print JSON
curl -k https://{$host}${path} \
        -H "hash: $hmac" \
        -H "key: $api_key" \
        -H "nonce: $nonce" \
        -H "time: $timestamp" \
        -H "x-timestamp: $timestamp" | \
# pipe the output to python's JSON pretty printer
        python -m json.tool