How do we share data between two different services

Answer 1

Sure - how about data binding? I don't have a lot of information to go on here - about your platform but most sufficiently advanced systems offer it in some form.

Answer 2

If you need to collect and aggregate data, you might want to consider using a database between the two layers. Or have I misunderstood something?

You should consider enhancing your question with more requirements: pretty much all options are open here.

Answer 3

You could replace your static shared data with some database representation, with a caching layer (like memcached) between the database and the webservice, so that most of the time the data is available very quickly from the cache, but can be retrieved from the database as needed.

Answer 4

I appreciate that you want to keep the architecture simple. Depending on the magnitude of items you have to look up and there permanency, you might just consider leveraging your file system or a message queue. It sounds like you want a file system, because that sounds the least amount of impact to your design.

If you start dealing with tens of thousands of small files, your directories could get hard to navigate and slow to do file lookups on. I typically shoot for about 1000 - 10000 files per directory, and concoct a routine that can generate a path to the file depending on the file name pattern. Keeping the number of subdirectories even is important, some file systems have a limit on the number of subdirectories in a parent directory.