Ruby Data extract from Kubernetes API - ruby

Trying to get the node role from Kubeclient api
Command: client.get_nodes()[0].metadata.labels
Kubeclient::Node beta.kubernetes.io/arch="amd64",
beta.kubernetes.io/instance-type="t2.medium",
beta.kubernetes.io/os="linux",
failure-domain.beta.kubernetes.io/region="eu-west-1",
failure-domain.beta.kubernetes.io/zone="eu-west-1a",
kubernetes.io/hostname="ip-X-X-XX-XX.eu-west-1.compute.internal",
kubernetes.io/role="**node**", node-role.kubernetes.io/node="">
I need to get the value for kubernetes.io/role="node" which is node, can some one help with the Ruby code to format this output.

maybe you can do this:
require 'kubeclient'
config = Kubeclient::Config.read('/path/to/.kube/config')
client = Kubeclient::Client.new(
config.context.api_endpoint,
config.context.api_version,
{
ssl_options: config.context.ssl_options,
auth_options: config.context.auth_options
}
)
// prints the label kubernetes.io/role
puts client.get_nodes()[0].metadata.labels['kubernetes.io/role']
// Iterate over all labels
client.get_nodes()[0].metadata.labels.each_pair do |key, value|
puts "#{key} = #{value}"
end

Related

merge two or more hashes from array in one json file

The issue that I'm facing is when I'm trying to automate a terraform script for bootstrap VMs. I keep all the templates in json files and depending on instance it will take one, two or more templates to create the node json file.
My code looks like:
template.each do |t|
node = JSON.parse(File.read("./terraform/node/#{t}.json"))
atr << node.each { |k, v| puts "#{k}: #{v}" }
concatenated = atr.flatten
temp = concatenated
File.open("./terraform/node/#{instance_name}.json","w") do |f|
f.puts JSON.pretty_generate(temp)
end
end
The output file looks like:
[{"haproxy"=>{"app_server_role"=>["s1", "s2"]}}, {"apache"=>{"listen_ports"=>["80", "443"]}}, {"tags"=>[]}]
The issue is that inside the array we have the exact template stored in erb :
{"haproxy"=>{"app_server_role"=>["s1", "s2"]}}
{"tags"=>[]} ...
What I want is a valid json with the content of templates like:
{"haproxy"=>{"app_server_role"=>["s1", "s2"]}, "apache"=>{"listen_ports"=>["80", "443"]}, {"tags"=>[]}
output_file = [{"haproxy"=>{"app_server_role"=>["s1", "s2"]}}, {"apache"=>{"listen_ports"=>["80", "443"]}}, {"tags"=>[]}]
output_file.each_with_object({}) { |h, h2| h2.merge!(h) }
=> {"haproxy"=>{"app_server_role"=>["s1", "s2"]}, "apache"=>{"listen_ports"=>["80", "443"]}, "tags"=>[]}
another great option suggested by mudasobwa:
output_file.reduce(&:merge)

Create a Ruby Hash out of an xml string with the 'ox' gem

I am currently trying to create a hash out of an xml documen, with the help of the ox gem
Input xml:
<?xml version="1.0"?>
<expense>
<payee>starbucks</payee>
<amount>5.75</amount>
<date>2017-06-10</date>
</expense>
with the following ruby/ox code:
doc = Ox.parse(xml)
plist = doc.root.nodes
I get the following output:
=> [#<Ox::Element:0x00007f80d985a668 #value="payee", #attributes={}, #nodes=["starbucks"]>, #<Ox::Element:0x00007f80d9839198 #value="amount", #attributes={}, #nodes=["5.75"]>, #<Ox::Element:0x00007f80d9028788 #value="date", #attributes={}, #nodes=["2017-06-10"]>]
The output I want is a hash in the format:
{'payee' => 'Starbucks',
'amount' => 5.75,
'date' => '2017-06-10'}
to save in my sqllite database. How can I transform the objects array into a hash like above.
Any help is highly appreciated.
The docs suggest you can use the following:
require 'ox'
xml = %{
<top name="sample">
<middle name="second">
<bottom name="third">Rock bottom</bottom>
</middle>
</top>
}
puts Ox.load(xml, mode: :hash)
puts Ox.load(xml, mode: :hash_no_attrs)
#{:top=>[{:name=>"sample"}, {:middle=>[{:name=>"second"}, {:bottom=>[{:name=>"third"}, "Rock bottom"]}]}]}
#{:top=>{:middle=>{:bottom=>"Rock bottom"}}}
I'm not sure that's exactly what you're looking for though.
Otherwise, it really depends on the methods available on the Ox::Element instances in the array.
From the docs, it looks like there are two handy methods here: you can use [] and text.
Therefore, I'd use reduce to coerce the array into the hash format you're looking for, using something like the following:
ox_nodes = [#<Ox::Element:0x00007f80d985a668 #value="payee", #attributes={}, #nodes=["starbucks"]>, #<Ox::Element:0x00007f80d9839198 #value="amount", #attributes={}, #nodes=["5.75"]>, #<Ox::Element:0x00007f80d9028788 #value="date", #attributes={}, #nodes=["2017-06-10"]>]
ox_nodes.reduce({}) do |hash, node|
hash[node['#value']] = node.text
hash
end
I'm not sure whether node['#value'] will work, so you might need to experiment with that - otherwise perhaps node.instance_variable_get('#value') would do it.
node.text does the following, which sounds about right:
Returns the first String in the elements nodes array or nil if there is no String node.
N.B. I prefer to tidy the reduce block a little using tap, something like the following:
ox_nodes.reduce({}) do |hash, node|
hash.tap { |h| h[node['#value']] = node.text }
end
Hope that helps - let me know how you get on!
I found the answer to the question in my last comment by myself:
def create_xml(expense)
Ox.default_options=({:with_xml => false})
doc = Ox::Document.new(:version => '1.0')
expense.each do |key, value|
e = Ox::Element.new(key)
e << value
doc << e
end
Ox.dump(doc)
end
The next question would be how can i transform the value of the amount key from a string to an integer befopre saving it to the database

Simple JSON not working in Ruby

Code:
#!/usr/bin/ruby
require 'rubygems'
require 'open-uri'
require 'json'
def getData
file = open("http://goo.gl/BI6h7a")
#json = JSON.parse(file.read)
end
getData
cveIds = #json['cve_id']
puts cveIds
You can see the JSON response here: http://goo.gl/BI6h7a
Console:
./cve.rb:13:in `[]': can't convert String into Integer (TypeError) from ./cve.rb:13:in `<main>'
I don't know why this is happening. "Convert String into Integer"? WHAT?
The #json gets the content fine, but the cveIds doesn't.
The top element in the json that you're reading is actually an Array, each of its elements is actually a hash, it's like this:
[
{
"cve_id": "CVE-2014-3976"
// other key/value pairs
}
{
"cve_id": "CVE-2014-3975"
// other key/value pairs
}
{
"cve_id": "CVE-2014-3974"
// other key/value pairs
}
// .... more hashes
]
so #json is an array. And if you want to access any of its elements you have to access it with a numeric integer index like, so:
#json[0] # => { "cve_id": "CVE-2014-3976", // other key/value pairs }
I think you are trying to collect the cve_id fields of all these hashes, this can be done as follows:
cveIds = #json.collect { |h| h["cve_id"] }
# The result:
=> ["CVE-2014-3976", "CVE-2014-3975", "CVE-2014-3974", "CVE-2014-3962", "CVE-2014-3961",
"CVE-2014-3878", "CVE-2014-3871", "CVE-2014-3842", "CVE-2014-3806", "CVE-2014-3792",
"CVE-2014-3791", "CVE-2014-3443", "CVE-2014-3247", "CVE-2014-3246", "CVE-2014-3225",
"CVE-2014-3216", "CVE-2014-3139", "CVE-2014-3138", "CVE-2014-3008", "CVE-2014-2996",
"CVE-2014-2994", "CVE-2014-2976", "CVE-2014-2850", "CVE-2014-2847", "CVE-2014-2671",
"CVE-2014-2668", "CVE-2014-2588", "CVE-2014-2587","CVE-2014-2586", "CVE-2014-2579"]
I'm not a ruby developer but what you have there is a list if dictionaries.
My guess in order for you to read cve_id you need to create some kind of a for loop.
for example in python I would write it like this:
for line in my_data:
print line['cve_id']
I guess in ruby it would look like this:
for i in #json do
cveIds = i['cve_id']
puts cveIds
end
cveIds = #json['cve_id']
What are you doing here is equivalent to:
arr = [1, 2, 3, 4]
puts arr["hello"] # using a string here on an indexed based array!
Hence your error message about Ruby trying to convert a String to an int.
Try the following instead
cveIds = #json.first['cve_id'] # equivalent to #json[0]['cve_id']
puts cveIds
In the above code sample, we are getting the first element from the array, which is a hash we can then access cve_id from.

Ruby: Parse API Response

I am trying to geht this script to run: http://dysinger.net/2008/10/13/using-amazon-ec2-metadata-as-a-simple-dns but dosnt work because it is using an old amazon sdk version, i rewrote it to use the new one:
#!/usr/bin/env ruby
require "rubygems"
require "aws-sdk"
%w(optparse rubygems aws-sdk resolv pp).each {|l| require l}
options = {}
parser = OptionParser.new do |p|
p.banner = "Usage: hosts [options]"
p.on("-a", "--access-key USER", "The user's AWS access key ID.") do |aki|
options[:access_key_id] = aki
end
p.on("-s",
"--secret-key PASSWORD",
"The user's AWS secret access key.") do |sak|
options[:secret_access_key] = sak
end
p.on_tail("-h", "--help", "Show this message") {
puts(p)
exit
}
p.parse!(ARGV) rescue puts(p)
end
if options.key?(:access_key_id) and options.key?(:secret_access_key)
puts "127.0.0.1 localhost"
AWS.config(options)
AWS::EC2.new(options)
answer = AWS::EC2::Client.new.describe_instances
answer.reservationSet.item.each do |r|
r.instancesSet.item.each do |i|
if i.instanceState.name =~ /running/
puts(Resolv::DNS.new.getaddress(i.privateDnsName).to_s +
" #{i.keyName}.ec2 #{i.keyName}")
end
end
end
else
puts(parser)
exit(1)
end
What this should do is outputing a new /etc/hosts file with my ec2 instances in it.
And i get a response =D, but answer is a hash and therefore i get the
error undefined method `reservationSet' for #<Hash:0x7f7573b27880>.
And this is my problem, since i dont know Ruby at all ( All I was doing was reading Amazon Documentation and playing around so i get an answer ). Somehow in the original example this seemed to work. I suppose that back then, the API did not return a hash, anyway...how can i iterate through a hash like above, to get this to work?
This code may help you:
answer = AWS::EC2::Client.new.describe_instances
reservations = answer[:reservation_set]
reservations.each do |reservation|
instances = reservation[:instances_set]
instances.each do |instance|
if instance[:instance_state][:name] == "running"
private_dns_name = instance[:private_dns_name]
key_name = instance[:key_name]
address = Resolv::DNS.new.getaddress(private_dns_name)
puts "{address} #{key_name}.ec2 #{key_name}"
end
end
end
Generally change your code from using methods with names e.g. item.fooBarBaz to using a hash e.g. item[:foo_bar_baz]
When you're learning Ruby the "pp" command is very useful for pretty-printing variables as you go, such as:
pp reservations
pp instances
pp private_dns_name

Manipulating XML files in ruby with XmlSimple

I've got a complex XML file, and I want to extract a content of a specific tag from it.
I use a ruby script with XmlSimple gem. I retrieve an XML file with HTTP request, then strip all the unnecessary tags and pull out necessary info. That's the script itself:
data = XmlSimple.xml_in(response.body)
hash_1 = Hash[*data['results']]
def find_value(hash, value)
hash.each do |key, val|
if val[0].kind_of? Hash then
find_value(val[0], value)
else
if key.to_s.eql? value
puts val
end
end
end
end
hash_1['book'].each do |arg|
find_value(arg, "title")
puts("\n")
end
The problem is, that when I change replace puts val with return val, and then call find_value method with puts find_value (arg, "title"), i get the whole contents of hash_1[book] on the screen.
How to correct the find_value method?
A "complex XML file" and XmlSimple don't mix. Your task would be solved a lot easier with Nokogiri, and be faster as well:
require 'nokogiri'
doc = Nokogiri::XML(response.body)
puts doc.xpath('//book/title/text()')

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