att / xfilter

arbitrary backend <-> crossfilter bridge

arbitrary backend <-> crossfilter bridge

This library implements enough of the crossfilter API and an asynchronous commit hook so that (in theory) any query engine can be connected to dc.js

Currently the query engine supported is Nanocubes (this library was originally called "nanofilter"): use xf.engine(xfilter.nanocube_queries) to connect with a Nanocubes server (demo).

Another example engine xfilter.fgb_queries() assumes the server takes queries that look like

{
    "filter": {
        "column": [
            "val1",
            "val2"
        ]
    },
    "groupby": [
        "column2"
    ]
}

The intent is that this library can be generalized to support any query engine.

xfilter's Issues

time out of joint

Here's a pretty bug:

Looks like time is skipping around. More likely, the data is not getting pulled in sequential order.

Docs for implementing other query providers

I am interested in implementing an Apache Arrow and Mapd backed query engine conforming to the interface of xfilter. It looks the interface would be the 3 functions named do_query, unpack_result, and fetch_schema. Is that right? Are there any documentations help me to understand the expected input and output of these functions? Thanks.

PS: I am aware that the issue tab is not for communication like this. But did not find any other ways. Please bear with me on it.