Call a REST API multiple times using Power Query

Hi Anonymous 

I work with something similar, without getting into tons of detail, here's some pointers to get you started and let me know if anything doesn't make sense or you want me to go through and part in more detail

If I've understood you right, I think it would be best to walk back from todays date (or a predefined date if you prefer) in increments.

1) Convert your code above into a function, where you can pass the start and end dates

Excuse that the escaped quotes might not be quite right

(startDate as text, endDate as text) =>

let
body = "{""from"":""" & startDate &""",""to"":""" & endDate & """"}",
Data= Web.Contents("***"),
DataRecord = Json.Document(Data)
in
DataRecord

2) Use a numbers table to generate a list of Start and End dates as required, invoke the above function

let
// Getting results for the last 365 days, in increments of 30 days
Source = List.Numbers(0, 365,30),
#"Converted to Table" = Table.FromList(Source, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
#"Added Custom" = Table.AddColumn(#"Converted to Table", "EndDate", each Date.AddDays(Date.From(DateTime.LocalNow()),[Column1]*-1)),
#"Added Custom1" = Table.AddColumn(#"Added Custom", "StartDate", each Date.AddDays([EndDate],-29)),
#"Invoked Custom Function" = Table.AddColumn(#"Added Custom1", "fnGetData", each fnGetData([StartDate], [EndDate]))
in
#"Invoked Custom Function"

3) Expand the results and get rid of any unneccesary columns

Hope that helps, let me know if you need any more info

Matt

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