soda-swift

soda-swift is a native Swift library to access Socrata OpenData servers. It is compatible with iOS 8 and OS X 10.10.

Getting Started

1. Get an access token for your app

2. Reference SODAKit/SODAClient.swift in Xcode

3. Initialize a SODAClient

let client = SODAClient(domain: "(Domain name of the server)", token: "(Your app's access token)")

For example,

let client = SODAClient(domain: "data.cityofchicago.org", token: "Uo25eXiX14zEd2K6EKAkeMIDW")

(that token won't work)

4. Query for data

Here is a simple filter query to find compressed natural gas stations in Chicago:

let fuelLocations = client.queryDataset("alternative-fuel-locations")

fuelLocations.filterColumn ("fuel_type_code", "CNG").get { res in
    switch res {
    case .Dataset (let data):

        // Display the data

    case .Error (let error):

    	// Show the error

    }
}

Note the use of filterColumn to get only compressed natural gas stations.

Also note that the final get function is asynchronous and that the last argument is a completion handler. For your convenience, soda-swift automatically schedules the handler on the main operation queue.

That completion handler is given an enumeration SODADatasetResult with two possible values:

• Dataset with an array of rows if the query succeeded.
• Error with the NSError if the query failed.

Query Options

There are many more query options than just filterColumn. We could have also written:

fuelLocations.filter("fuel_type_code = 'CNG'")

We can also order the results:

fuelLocations.orderAscending("station_name")

We can then limit the results and control the offset to perform paging:

fuelLocations.limit(10).offset(0)

Chaining Queries

Queries can be easily composed and stored in variables. This allows you to keep your code clean and easily construct derivative queries.

For example, we may have an app that has a base query called fuelLocations:

let fuelLocations = client.queryDataset("alternative-fuel-locations")

The app allows the user to choose two types of stations: natural gas and electric. This decision is encapsulated in the query stations.

let userWantsNaturalGas = true // Get this from the UI

let stations = fuelLocations.filterColumn("fuel_type_code", userWantsNaturalGas ? "CNG" : "ELEC")

The app can also display the data sorted in two different directions and stores this in orderedStations:

let userWantsAscending = true // Get this from the UI

let orderedStations = userWantsAscending ?
    stations.orderAscending("station_name") :
    stations.orderDescending("station_name")

Now the app can easily query the results:

orderedStations.get { result in

    // Display the data or the error

}

API Reference

The full API Reference can be found in Reference.md.

Sample App

A sample app that shows recent police incidents in Seattle is included.

1. Open soda-swift.xcodeproj
2. Modify SODASample/AppDelegate.swift to insert your access token
3. Ensure that the target SODA iOS Sample is selected
4. Run