Swift

Firebase GET - Reading Data

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Demonstrates how to read parts of a Firebase JSON database. The data used in this example is at Chilkat Firebase Pigs Database, and is shown here:

Swift

func chilkatTest() {
    var success: Bool = false

    // Demonstrates how to read parts of a Firebase JSON database.

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // This example assumes a JWT authentication token, if required, has been previously obtained.
    // See Get Firebase Access Token from JSON Service Account Private Key for sample code.

    // Load the previously obtained Firebase access token into a string.
    let fac = CkoFileAccess()!
    var accessToken: String? = fac.readEntireTextFile(path: "qa_data/tokens/firebaseToken.txt", charset: "utf-8")
    if fac.lastMethodSuccess != true {
        print("\(fac.lastErrorText!)")
        return
    }

    let rest = CkoRest()!

    // Make the initial connection (without sending a request yet).
    // Once connected, any number of requests may be sent.  It is not necessary to explicitly
    // call Connect before each request.  
    success = rest.connect(hostname: "chilkat.firebaseio.com", port: 443, tls: true, autoReconnect: true)
    if success != true {
        print("\(rest.lastErrorText!)")
        return
    }

    // If authentication is required...
    let authGoogle = CkoAuthGoogle()!
    authGoogle.accessToken = accessToken
    rest.setAuthGoogle(authProvider: authGoogle)

    // Chilkat's sample data (pig-rescue data) is publicly readable at: https://chilkat.firebaseio.com/.json

    // Let's get the animals with the shallow parameter so we can see how many pigs exist.
    var jsonResponse: String? = rest.fullRequestNoBody(httpVerb: "GET", uriPath: "/pig-rescue/animal.json?shallow=true")
    if rest.lastMethodSuccess != true {
        print("\(rest.lastErrorText!)")
        return
    }

    // The JSON returned should look like this:  
    // {"-KI3bD-FU_Dake7sYOiP":true,"-KI3bD-FU_Dake7sYOiT":true,"-KI3bD-FU_Dake7sYOiS":true,"-KI3bD-FU_Dake7sYOiU":true,"-KI3bD-FU_Dake7sYOiV":true,"-KI3bD-FU_Dake7sYOiR":true,"-KI3bD-FU_Dake7sYOiQ":true}
    print("\(jsonResponse!)")

    // Parse the response so we can iterate over each pig in the database..
    let piggyPath = CkoStringBuilder()!
    let shallow = CkoJsonObject()!
    let piggyData = CkoJsonObject()!
    shallow.load(json: jsonResponse)
    var count: Int = shallow.size.intValue
    var i: Int = 0
    while i < count {

        // Get each individual pig's data.
        piggyPath.clear()
        piggyPath.append(value: "/pig-rescue/animal/")
        piggyPath.append(value: shallow.name(at: i))
        piggyPath.append(value: "/.json")

        var piggyJson: String? = rest.fullRequestNoBody(httpVerb: "GET", uriPath: piggyPath.getAsString())
        if rest.lastMethodSuccess != true {
            print("\(rest.lastErrorText!)")
            return
        }

        // Show this piggy's data...
        // An example of one pig's data is shown here:
        // {"birth":"February, 1998","from":"Middle Ave.","gender":"F","in-date":"January, 2000",
        //   "name":"Molly II","picture":{"caption":"Molly in the Pasture","description":"Black pig","file":"molly_th.jpg"},
        //   "species":"pot belly pig","type":"Cathy's Herd"}
        print("---- \(i) ----")
        print("\(piggyJson!)")

        // Let's get the pig's name, and the caption of the picture.
        piggyData.load(json: piggyJson)
        print("name: \(piggyData.string(of: "name")!)")
        print("caption: \(piggyData.string(of: "picture.caption")!)")

        i = i + 1
    }

    // Note: In many of the Chilkat examples, you may notice strange ways
    // of doing something that should be simpler and shorter.  For example,
    // building the piggyPath (above) could've been written differently,
    // with some simple string concatenation.
    // 
    // The reason is that the Chilkat examples are written in a 
    // proprietary "example code" scripting language,
    // and then automatically generated to each of the different programming
    // languages you see on example-code.com.  The code generation is
    // limited in what it can do.  For example, string concatentation
    // is not yet a feature of the "example code" scripting language (as of May 2016), 
    // and therefore you won't see the use of a programming language's string
    // concatentation operators in any example.  
    // 

}