Technical test to get the aggregated stock results for a given symbol, originally done in C# but I tried it out in F#

stock.fsx

#r @"./packages/fsharp-data/netstandard2.0/Fsharp.Data.dll"
#r @"./packages/newtonsoft.json/netstandard2.0/Newtonsoft.Json.dll"
open System
open FSharp.Data
open Newtonsoft.Json.Linq

let timeSeriesUrl = "https://www.alphavantage.co/query?function=TIME_SERIES_DAILY&symbol=%s&outputsize=full&apikey=A3U8E3F7N3A85K86"

type TimeSeries = FSharp.Data.JsonProvider<"""{
   "2. high": "123.4567",
   "3. low": "123.4567"
}""">

let renderStockUrl symbol =
  sprintf (Printf.StringFormat<string->string>(timeSeriesUrl)) symbol

let queryApi url = 
  FSharp.Data.Http.RequestString url

let parseStockResponse response =
  let json = JObject.Parse response
  
  let timeSeries = json.Item "Time Series (Daily)"
  timeSeries.Children()
  |> Seq.cast<JToken>
  |> Seq.map(fun token -> token.ToObject<JProperty>())
  |> Seq.map(fun prop -> prop, TimeSeries.Parse(prop.Value.ToString()))
  |> Seq.map(fun (prop, entry) -> DateTime.Parse prop.Name, entry.``2High``, entry.``3Low``)

let aggregateStockTimeSeries timeSeries =
  timeSeries
  |> Seq.groupBy(fun (date : DateTime, _, _) -> (date.Year, date.Month))
  |> Seq.map(fun ((year, month), values) -> 
      let date = DateTime(year, month, 1)
      let minLow = values |> Seq.map(fun (_, _, low) -> low) |> Seq.maxBy(fun low -> low)
      let maxHigh = values |> Seq.map(fun (_, high, _) -> high) |> Seq.maxBy(fun high -> high)
      date, minLow, maxHigh)

let renderAggrigatedStockResultsFor symbol = 
  renderStockUrl symbol
  |> queryApi
  |> parseStockResponse
  |> aggregateStockTimeSeries
  |> Seq.iter(fun (date, low, high) -> printf "%s %M %M\n" (date.ToString("yyyy-MM")) low high)

renderAggrigatedStockResultsFor "MSFT"