I have Google analytics data ( dimensions and metrics) stored in a mongoDB database and I would like to query this data in a MDX style, then display it on the software I am working on. I was wondering if there is a FREE software than performs multidimensional queries on such data and then offers the results via a REST API so they can be consumed with other software.
Elasticsearch or Kibana may be what you are looking for. You can install them for free yourself but they are quite technical. This should not be a problem as you are mentioning MDX style which, in and of itself, is quite an advanced technology.
I would suggest MetaBase it has a lot of features, plus it takes only 5-minutes to install and supports a lot of databases.