You probably want this either as a dev dependency, in which case you would install it like so:
composer require --dev violinist-dev/composer-changelog-fetcher
Or you might want to install it as a global tool, in which case you would do this:
composer global require violinist-dev/composer-changelog-fetcher
You probably want to invoke this within a project. Let's say you run composer outdated:
symfony/http-foundation v3.4.22 v3.4.23 Symfony HttpFoundation Component
...and then you want to know what changed. Let's assume your bin directory is in vendor/bin/:
./vendor/bin/changelog-fetcher fetch -p symfony/http-foundation -f v3.4.22 -t v3.4.23
..then you might get output like this:
9a96d77: Apply php-cs-fixer rule for array_key_exists() (https://github.com/symfony/http-foundation/commit/9a96d77)
You can also get this output as json (in this example piped into jq for readability):
./vendor/bin/changelog-fetcher fetch -p symfony/http-foundation -f v3.4.22 -t v3.4.23 -d ~/Sites/violinist -o json | jq
[
{
"hash": "9a96d77",
"message": "Apply php-cs-fixer rule for array_key_exists()",
"link": "https://github.com/symfony/http-foundation/commit/9a96d77"
}
]