# Feedback for an API-wrapper

**URL:** <https://discourse.julialang.org/t/feedback-for-an-api-wrapper/32888>\
**Category:** New to Julia\
**Created:** [January 2, 2020, 7:36pm UTC](https://discourse.julialang.org/t/feedback-for-an-api-wrapper/32888 "2020-01-02T19:36:48Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![R.Heijmann](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/r.heijmann/32/12088_2.png) [@R.Heijmann](https://discourse.julialang.org/u/R.Heijmann)\
**Post date:** [January 2, 2020, 7:36pm UTC](https://discourse.julialang.org/t/feedback-for-an-api-wrapper/32888/1 "2020-01-02T19:36:48Z")

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Hi there, I discovered Julia just a couple of hours ago. And wanted to give it a try.

Could you give me feedback for my AccuWeather API-wrapper. I still have to find a way to make a few arguments optional. Some additions to strings can be coupled togethe, but for simplicity I have left them this way (it makes it easy to copy/paste a function for other API-methods). The ‘make-API-call’ functions uses HTTP.requests to send a GET-request and scans the response for errors.

```julia
function get_forecast(apikey::String, timespan::String, time::Int64, locationKey::String, language::String, details::Bool, metric::Bool)
    # Daily/Hourly forecasts for a specific location. Forecast searches require a location key. Please use the Locations API to obtain the location key for your desired location. By default, a truncated version of the hourly forecast data is returned. The full object can be obtained by passing "details=true" into the url string.

    url = "http://dataservice.accuweather.com/forecasts/v1/"

    # Add required parameters to the URL
    url = url * timespan * "ly"
    # Accepted values: day hour
    
    url = url * string(time) * timespan * "/"
    # Accepted values:
    # - Days: 1/5/10/15
    # - Hours: 1/12/24/72/120
    # Example: If "timespan" is set to "day" and "time" to 10, it gets the forecast for 15 days.
    
    url = url * string(locationKey)
    url = url * "?apikey=" * apikey

    # Add optional parameters to the URL
    if language != Nothing url = url * "&language=" * language end
    if details == true url = url * "&details=true" end
    if metric == true url = url * "&metric=true" end
    

    return make_API_call(url)
end

```

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**Author:** ![rdeits](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/rdeits/32/286_2.png) [@rdeits](https://discourse.julialang.org/u/rdeits)\
**Post date:** [January 2, 2020, 8:36pm UTC](https://discourse.julialang.org/t/feedback-for-an-api-wrapper/32888/2 "2020-01-02T20:36:56Z")

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Welcome!

My first suggestion would be to use the type system to make the time arguments easier to specify. Your current function asks for a `timespan::String` and a `time::Int64`, but it’s not clear from those types what inputs are actually allowed. For example, it looks like I can do `"day", 5` and `"hour", 120`, but doing `"hour", 18` or `"minute", 60` will likely cause an error.

You could make this function friendlier by taking in a dedicated type representing an amount of time. Julia has some useful types in the built-in `Dates` package. For example:

```julia
julia> using Dates
                                                                                                                                                                                                                                                                                                                                      
julia> Day(5)
5 days                                                                                                                                                                                                                                                                                                                                

julia> Hour(12)
12 hours

```

You could write a function which takes in a time range given in hours or days like this:

```julia
function get_forecast(apikey, duration::Union{Hour, Day}, <your other arguments here>)
  url = <your code here>
  url = url * url_date_string(duration)
  <more code here>
end

```

And then you could define `url_date_string` like this:

```julia
url_date_string(d::Day) = "$(d.value)daily"

url_date_string(h::Hour) = "$(h.value)hourly"

```

for example:

```julia
julia> url_date_string(Day(5))
"5daily"

julia> url_date_string(Hour(12))
"12hourly"

```

The advantage of this representation is that you can be extremely clear about what kinds of date ranges are allowed.