Add support to dynamically set INDEX_META_PATH

README.md

@@ -137,6 +137,13 @@ This command will execute full reindex at first call - and then will be storing
 
 Please note: Magento2 has a bug with altering `updated_at` field. Please install [a fix for that](https://github.com/codepeak/magento2-productfix) before using this method: 
 
+If you have a multistore setup and would like to use the delta indexer for each storeview you can not use the delta timestamp from `.lastIndex.json` for all stores; instead
+you will need to set the `INDEX_META_PATH` to a unique value for each store you are indexing. For instance:
+
+```
+export INDEX_META_PATH=.lastIndex-UK.json && node --harmony cli.js productsdelta --partitions=1
+```
+
 ```bash
 composer require codepeak/magento2-productfix
 php bin/magento cache:flush

src/cli.js

@@ -9,7 +9,7 @@ let config = require('./config');
 let logger = require('./log');
 let factory = new AdapterFactory(config);
 const jsonFile = require('jsonfile')
-const INDEX_META_PATH = '.lastIndex.json'
+const INDEX_META_PATH = process.env.INDEX_META_PATH ? process.env.INDEX_META_PATH : '.lastIndex.json'
 
 let kue = require('kue');
 let queue = kue.createQueue(Object.assign(config.kue, { redis: config.redis }));