Hi
I haven't peronsally had a play with the approaches below yet, but am aware of them, which may be all you need to get started. If more specific help is required, then we'll probably need another user more skilled in these areas to weigh in.
MS provide third-party access to SSAS via XMLA endpoint, which is a SOAP-based protocol for working with Analysis Services, so any language with good SOAP support, so Java might be a better fit than JS here.
Note that XMLA is available in preview in Power BI, but only if you have premium, so SSAS might be the better option.
You should also be able to use XMLA in conjunction with SSAS-specific scripting languages:
- Developing with Analysis Services Scripting Language (ASSL)
- Tabular Model Scripting Language (TMSL) Reference
Hopefully this should give you something to get started with.
Good luck!
Daniel
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