(Ruby) Firebase GET - Reading Data

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:

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require 'chilkat'

# 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.
fac = Chilkat::CkFileAccess.new()
accessToken = fac.readEntireTextFile("qa_data/tokens/firebaseToken.txt","utf-8")
if (fac.get_LastMethodSuccess() != true)
    print fac.lastErrorText() + "\n";
    exit
end

rest = Chilkat::CkRest.new()

# 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("chilkat.firebaseio.com",443,true,true)
if (success != true)
    print rest.lastErrorText() + "\n";
    exit
end

# If authentication is required...
authGoogle = Chilkat::CkAuthGoogle.new()
authGoogle.put_AccessToken(accessToken)
rest.SetAuthGoogle(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.
jsonResponse = rest.fullRequestNoBody("GET","/pig-rescue/animal.json?shallow=true")
if (rest.get_LastMethodSuccess() != true)
    print rest.lastErrorText() + "\n";
    exit
end

# 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 + "\n";

# Parse the response so we can iterate over each pig in the database..
piggyPath = Chilkat::CkStringBuilder.new()
shallow = Chilkat::CkJsonObject.new()
piggyData = Chilkat::CkJsonObject.new()
shallow.Load(jsonResponse)
count = shallow.get_Size()
i = 0
while i < count

    # Get each individual pig's data.
    piggyPath.Clear()
    piggyPath.Append("/pig-rescue/animal/")
    piggyPath.Append(shallow.nameAt(i))
    piggyPath.Append("/.json")

    piggyJson = rest.fullRequestNoBody("GET",piggyPath.getAsString())
    if (rest.get_LastMethodSuccess() != true)
        print rest.lastErrorText() + "\n";
        exit
    end

    # 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.to_s() + " ----" + "\n";
    print piggyJson + "\n";

    # Let's get the pig's name, and the caption of the picture.
    piggyData.Load(piggyJson)
    print "name: " + piggyData.stringOf("name") + "\n";
    print "caption: " + piggyData.stringOf("picture.caption") + "\n";

    i = i + 1
end

# 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.  
#