let remoteOpts = {
    remoteCallbacks: {
        certificateCheck: function () {
            return 1;
        },
        credentials: function (url, username) {
            return git.Cred.sshKeyFromAgent(username);
        }
    }
};

function getFileFromBranch(branch, filePath) {
    let repository;

    return git.Repository.open(config.git.cloneTo)
        .catch(function (err) {
            if (err.message.startsWith('Failed to resolve')) {
                winston.info('Repo not found, cloning');

                // USED HERE
                return git.Clone(config.git.repo, config.git.cloneTo, remoteOpts);
            } else {
                winston.error(err);
                throw err;
            }
        })
        .then(function (repo) {
            repository = repo;

            winston.log('verbose', 'Changing branch');
            return repo.checkoutBranch(branch);
        })
        .catch(function (err) {
            if (/Reference '([^']+)' not found/.test(err.message)) {
                winston.info('Branch not found, fetching');

                // USED HERE
                let remoteCallbacks = remoteOpts.remoteCallbacks;
                return repository.fetch('origin', remoteCallbacks, true)
                    .then(function () {
                        return repository.checkoutBranch(branch);
                    });
            } else {
                winston.error(err);
                throw err;
            }
        })
        .then(function () {
            return fs.readFile(path.join(config.git.cloneTo, filePath));
        });
}