The purpose of this script is to allow Atlassian Stash to send post-receive hooks to PHPCI

post-receive.sh

#!/bin/bash
# Author: Michael Gray 
# Description: The purpose of this script is to allow Atlassian Stash to send post-receive hooks to PHPCI 
# using the external post-receive POST hook request.
# Email: hello@graymic.co.uk
(
        PROJECT_ID=$1
        PHPCI_URL="http://path.to.ci.server.com"
        echo "Script name: $0"
        echo "Positional arguments: ${@}"
        echo "STASH_USER_NAME: $STASH_USER_NAME"
        echo "STASH_USER_EMAIL: $STASH_USER_EMAIL"
        echo "STASH_REPO_NAME: $STASH_REPO_NAME"
        echo "STASH_IS_ADMIN: $STASH_IS_ADMIN"

        while read from_ref to_ref ref_name; do
                BRANCH=$(git rev-parse --symbolic --abbrev-ref $ref_name)
                echo "Sending webhook"
                curl "$PHPCI_URL/webhook/git/$PROJECT_ID?branch=$BRANCH&commit=$to_ref"
        done

) | tee -a /tmp/atlassian-post-receive.log

Ensure you make the post-receive.sh script executable before assigning the post-receive hook in stash.