SwiftUI getting data from Data(contentsOf: file)

Question

I'm trying to get some content from a .txt file by doing

let ruterQuery = loadR(filename: "content.txt")


func loadR( filename: String )  -> String  {
    let data: Data

    guard let file = Bundle.main.url(forResource: filename, withExtension: nil)
        else {
            fatalError("Couldn't find \(filename) in main bundle.")
    }

    do {
        data = try Data(contentsOf: file)
    } catch {
        fatalError("Couldn't load \(filename) from main bundle:\n\(error)")
    }

    print(data)

    return "done"

}

But when I print the data it only says "2045 bytes", how do I get the actual content of the file?

This is the content.txt, it's for an api url as a "query" of what fields to be returned. So the url will be "https://api.myapi.com/planner?query=" + content.txt

"{\n\tplaces(\n\t\tids:[\"ABC:StopPlace:8329\", \"ABC:StopPlace:0808\"]\n\t) {\n\t\tname\n\t\tid\n\t\testimatedCalls(timeRange: 72100, numberOfDepartures: 20) {\n\n\t\t\trealtime\n\t\t\trealtimeState\n\t\t\texpectedDepartureTime\n\t\t\tpredictionInaccurate\n\t\t\tdestinationDisplay {\n\t\t\t\tfrontText\n\t\t\t}\n\t\t\tquay {\n\t\t\t\tid\n\t\t\t}\n\n\t\t\tsituations {\n\t\t\t\tid\n\t\t\t\tlines {\n\t\t\t\t\tid\n\t\t\t\t}\n\t\t\t\tsummary {\n\t\t\t\t\tvalue\n\t\t\t\t\tlanguage\n\t\t\t\t}\n\t\t\t\tstopPlaces {\n\t\t\t\t\tid\n\t\t\t\t}\n\t\t\t\tdescription {\n\t\t\t\t\tvalue\n\t\t\t\t\tlanguage\n\t\t\t\t}\n\t\t\t\tvalidityPeriod {\n\t\t\t\t\tstartTime\n\t\t\t\t\tendTime\n\t\t\t\t}\n\t\t\t\tseverity\n\t\t\t\tsituationNumber\n\t\t\t}\n\n\t\t\tserviceJourney {\n\t\t\t\tid\n\t\t\t\tpublicCode\n\t\t\t\tprivateCode\n\t\t\t\tserviceAlteration\n\t\t\t\ttransportSubmode\n\t\t\t\tdirectionType\n\n\t\t\t\tnotices {\n\t\t\t\t\tid\n\t\t\t\t\ttext\n\t\t\t\t\tpublicCode\n\t\t\t\t}\n\n\t\t\t\tjourneyPattern {\n\t\t\t\t\tid\n\t\t\t\t\tline{\n\t\t\t\t\t\tid\n\t\t\t\t\t\tname\n\t\t\t\t\t\tpublicCode\n\t\t\t\t\t\ttransportMode\n\t\t\t\t\t\ttransportSubmode\n\t\t\t\t\t\tpresentation {\n\t\t\t\t\t\t\ttextColour\n\t\t\t\t\t\t\tcolour\n\t\t\t\t\t\t}\n\t\t\t\t\t\tsituations {\n\t\t\t\t\t\t\tid\n\t\t\t\t\t\t\tdescription {\n\t\t\t\t\t\t\t\tvalue\n\t\t\t\t\t\t\t\tlanguage\n\t\t\t\t\t\t\t}\n\t\t\t\t\t\t\tvalidityPeriod {\n\t\t\t\t\t\t\t\tstartTime\n\t\t\t\t\t\t\t\tendTime\n\t\t\t\t\t\t\t}\n\t\t\t\t\t\t}\n\t\t\t\t\t}\n\t\t\t\t}\n\n\t\t\t\tsituations {\n\t\t\t\t\tid\n\t\t\t\t\tlines {\n\t\t\t\t\t\tid\n\t\t\t\t\t}\n\t\t\t\t\tsummary {\n\t\t\t\t\t\tvalue\n\t\t\t\t\t\tlanguage\n\t\t\t\t\t}\n\t\t\t\t\tstopPlaces {\n\t\t\t\t\t\tid\n\t\t\t\t\t}\n\t\t\t\t\tdescription {\n\t\t\t\t\t\tvalue\n\t\t\t\t\t\tlanguage\n\t\t\t\t\t}\n\t\t\t\t\tvalidityPeriod {\n\t\t\t\t\t\tstartTime\n\t\t\t\t\t\tendTime\n\t\t\t\t\t}\n\t\t\t\t\tseverity\n\t\t\t\t\tsituationNumber\n\t\t\t\t}\n\t\t\t}\n\n\t\t}\n\t}\n}\n"

score 4 · Accepted Answer · answered Nov 03 '19 at 21:36

The content of the file is JSON rather than simply text.

You get the the string representation with

func loadR(filename: String ) -> String  {

    let url = Bundle.main.url(forResource: filename, withExtension: "txt")!
    let data = try! Data(contentsOf: url)
    let string = String(data: data, encoding: .utf8)!   
    print(string)
    return string
}

If the code crashes you made a design mistake. As files in the bundle are immutable at runtime the code must not crash.

Another bad practice are all the unnecessary whitespace characters. Unlike a human being the device doesn't care about prettyPrinting

Thank you very much for a detailed answer! I'm still brand new to swift! This worked!. I'd like to remove the whitespaces as well, however I'm not sure how to. Now it's throwing an error when I try to use the url, I didn't want to mess up this question so I posted a new one here: https://stackoverflow.com/questions/58685419/swiftui-parse-query-to-json-string-for-api if you have the time. Thanks either way! — Cinta, Nov 03 '19 at 23:08

SwiftUI getting data from Data(contentsOf: file)

1 Answers1