export default function(foreignKey, nspaceKey, hash = JSON.stringify) {
return function(primaryKey, slugKey, foreignKeyValue) {
if (foreignKeyValue == null || foreignKeyValue.length < 1) {
throw new Error('Unable to create fingerprint, missing foreignKey value');
}
return function(item) {
const slugKeys = slugKey.split(',');
const slugValues = slugKeys.map(function(slugKey) {
if (item[slugKey] == null || item[slugKey].length < 1) {
throw new Error('Unable to create fingerprint, missing slug');
return item[slugKey];
});
const nspaceValue = item[nspaceKey] || 'default';
return {
...item,
...{
[nspaceKey]: nspaceValue,
[foreignKey]: foreignKeyValue,
[primaryKey]: hash([nspaceValue, foreignKeyValue].concat(slugValues)),
},
};