how to create hash within hash - ruby-on-rails

How am I able to create a hash within a hash, with the nested hash having a key to indentify it. Also the elements that I create in the nested hash, how can I have keys for them as well
for example
test = Hash.new()
#create second hash with a name?? test = Hash.new("test1")??
test("test1")[1] = 1???
test("test1")[2] = 2???
#create second hash with a name/key test = Hash.new("test2")???
test("test2")[1] = 1??
test("test2")[2] = 2??
thank you

Joel's is what I would do, but could also do this:
test = Hash.new()
test['test1'] = Hash.new()
test['test1']['key'] = 'val'

my_hash = { :nested_hash => { :first_key => 'Hello' } }
puts my_hash[:nested_hash][:first_key]
$ Hello
or
my_hash = {}
my_hash.merge!(:nested_hash => {:first_key => 'Hello' })
puts my_hash[:nested_hash][:first_key]
$ Hello

h1 = {'h2.1' => {'foo' => 'this', 'cool' => 'guy'}, 'h2.2' => {'bar' => '2000'} }
h1['h2.1'] # => {'foo' => 'this', 'cool' => 'guy'}
h1['h2.2'] # => {'bar' => '2000'}
h1['h2.1']['foo'] # => 'this'
h1['h2.1']['cool'] # => 'guy'
h1['h2.2']['bar'] # => '2000'

Related

TypeError no implicit conversion of Symbol into Integer

Hash
data = {
:recordset => {
:row => {
:property => [
{:name => "Code", :value => "C0001"},
{:name => "Customer", :value => "ROSSI MARIO"}
]
}
},
:#xmlns => "http://localhost/test"
}
Code Used
result = data[:recordset][:row].each_with_object([]) do |hash, out|
out << hash[:property].each_with_object({}) do |h, o|
o[h[:name]] = h[:value]
end
end
I cannot get the following output:
[{"Code"=>"C0001", "Customer"=>"ROSSI MARIO", "Phone1"=>"1234567890"}
Error message:
TypeError no implicit conversion of Symbol into Integer
It works correctly in case of multi records
data = {
:recordset => {
:row => [{
:property => [
{:name => "Code", :value => "C0001"},
{:name => "Customer", :value => "ROSSI MARIO"},
{:name => "Phone1", :value => "1234567890"}
]
}, {
:property => [
{:name => "Code", :value => "C0002"},
{:name => "Customer", :value => "VERDE VINCENT"},
{:name => "Phone1", :value => "9876543210"},
{:name => "Phone2", :value => "2468101214"}
]
}]
},
:#xmlns => "http://localhost/test"
}
Code used
data.keys
#=> [:recordset, :#xmlns]
data[:recordset][:row].count
#=> 2 # There are 2 set of attribute-value pairs
result = data[:recordset][:row].each_with_object([]) do |hash, out|
out << hash[:property].each_with_object({}) do |h, o|
o[h[:name]] = h[:value]
end
end
#=> [
# {"Code"=>"C0001", "Customer"=>"ROSSI MARIO", "Phone1"=>"1234567890"},
# {"Code"=>"C0002", "Customer"=>"VERDE VINCENT", "Phone1"=>"9876543210", "Phone2"=>"2468101214"}
# ]
In the first case data[:recordset][:row] is not an Array, it's a Hash, so when you iterate it, the hash variable becomes the array:
[:property, [{:name=>"Code", :value=>"C0001"}, {:name=>"Customer", :value=>"ROSSI MARIO"}]]
In the second case, it's an Array, not a Hash, so when you iterate it, it becomes the hash:
{:property=>[{:name=>"Code", :value=>"C0001"}, {:name=>"Customer", :value=>"ROSSI MARIO"}, {:name=>"Phone1", :value=>"1234567890"}]}
You're always assuming it's the second format. You could force it into an array, and then flatten by 1 level to treat both instances the same:
result = [data[:recordset][:row]].flatten(1).each_with_object([]) do |hash, out|
out << hash[:property].each_with_object({}) do |h, o|
o[h[:name]] = h[:value]
end
end
# => [{"Code"=>"C0001", "Customer"=>"ROSSI MARIO"}] # result from example 1
# => [{"Code"=>"C0001", "Customer"=>"ROSSI MARIO", "Phone1"=>"1234567890"},
# {"Code"=>"C0002", "Customer"=>"VERDE VINCENT",
# "Phone1"=>"9876543210", "Phone2"=>"2468101214"}] # result from example 2
It's tempting to try and use Kernal#Array() instead of [].flatten(1), but you have to remember that Hash implements to_a to return a nested array of keys and values, so Kernal#Array() doesn't work like you'd want it to:
Array(data[:recordset][:row]) # using the first example data
# => [[:property, [{:name=>"Code", :value=>"C0001"}, {:name=>"Customer", :value=>"ROSSI MARIO"}]]]
You can create an array if it's not an array to normalize the input before processing it.
info = data[:recordset][:row]
info = [info] unless info.is_an? Array
result = info.each_with_object([]) do ....

undefined method `values_at' for nil:NilClass when I use WashOut gem

I am new to WSDL.
Code (I have added in the view directly - for test): (Page: http://localhost:3000/ccapis )
require 'savon'
client = Savon::Client.new(wsdl: "http://localhost:3000/ccapis/wsdl")
result = client.call(:fetch_prizes, message: { :gl_id => "123456789" })
result.to_hash
And in the controller:
soap_action "fetch_prizes",
:args => { :gl_id => :string },
:return => [:array]
def fetch_prizes
glnumber = params[:gl_id ]
prize = Prize.where(:gl_id => glnumber)
prize_to_show = []
a_hash = {}
prize.each do |p|
a_hash = { :prize => p.prize.to_s, :score => p.score.to_s, :date => p.round_date.to_s }
prize_to_show.push a_hash
a_hash = nil
end
render :soap => prize_to_show
end
When I try and run this in the Console all are good and I can see the result.to_hash but when I go to http://0.0.0.0:3000/ccapis I get the error that I mentioned above.
Explanation of what I am trying to achieve:
I need to supply a WSDL for a client which fetches all the prizes based on a score.
If My approach is wrong please direct me to a document so I can have a read and get a better understanding. Thanks again.

Accessing a hashmap as an attribute of an object

I have an instance of an object that is created like this:
Example.create(:attrib0 => {
:attrib1 => value,
:attrib2 => [
{:attrib3 => value},
{:attrib4 => value}
]
})
How can I access :attrib4?
You should use serialize in your model, then you'll be able to return the hash correctly:
class SomeModel < ActiveRecord::Base
serialize :attrib0
end
Then the following should return the hash
hash = #model.attrib0
# => {:attrib1 => value, :attrib2 => [{:attrib3 => value}, {:attrib4 => value}]
# now to access attrib4 you need to get the attrib2 array,
# then grab attrib4 by its index:
hash[:attrib2][1]
# => {:attrib4 => value}
# or to get the value:
hash[:attrib2][1][:attrib4]
# => value
The above however can get quite complex and ugly, which is why I recommended creating another model for these attributes instead.
I think you should use nested attributes. Here's how it can be:
class Example
has_one :attrib0
accepts_nested_attributes_for :attrib0
end
params = { :attrib0 => { :attrib1 => value1,
:attrib2 => [ {:attrib3 => value3}, {:attrib4 => value4} ] }
}
example = Example.create(params[:attrib0])
example.attrib0.attrib1 #=> value1
example.attrib0.attrib2 #=> [ {:attrib3 => value3}, {:attrib4 => value4} ]
Using Ruby technique only:
h = {:attrib0 => {
:attrib1 => :value1,
:attrib2 => [
{:attrib3 => :value2},
{:attrib4 => :value3}
]
}}
p h[:attrib0][:attrib2].last[:attrib4] #=> :value3

Accepting either a hash or an array of hashes as arguments to a Ruby method

I have the method:
def self.store(params)
params.each { }
end
It works perfectly, if I pass an Array of Hashes:
params = [ { key: 'value' }, { key: 'value' } ]
However, I might want to pass only a single Hash, instead of an Array of Hashes:
params = { key: 'value' }
What would be the cleanest Ruby way to convert a Hash into an Array of Hashes?
The Array() method a kind of ensures, that an array is always returned, but when the Hash is passed, it is converted into an Array itself.
Array({ key: 'value' }) => [[:key, 'value']]
What I need:
{ key: 'value' } => [ { key: 'value' } ]
Is there any nice way to implement this, or do I have to do a manual type checking with is_a?(Array) ?
For me, the best solution is to change the method to:
def self.store(*hashes)
params = hashes.flatten
puts params.inspect
end
If you pass a single hash, it will be an array
If you pass an array of hashes, it remains the same
If you pases N hashes, it compacts all parameters into a one dimensional array.
You can pass whatever you want.
self.store({:key => 'value'}) # => [{:key => 'value'}]
self.store({:key => 'value'}, {:foo => 'bar'}) # => [{:key => 'value'}, {:foo => 'bar'}]
self.store([{:key => 'value'}, {:foo => 'bar'}]) # => [{:key => 'value'}, {:foo => 'bar'}]
Try this
def self.store(params)
params = [params].flatten
...
end
I would do it like this:
def self.store(params)
(params.is_a?(Array) ? params : [params]).each {|single_hash| }
end

Ruby on Rails: I'm trying to recursively generate a hash, but I get {...} where there is supposed to be another depth of data

This is what I've been getting:
{:user=>{:employees=>{...}, :login=>"dernalia", :id=>1, :role=>2}}
What is generating the hash:
def management_tree(args = {})
args = {:users => [], :result => {}}.merge(args) #defaults
result = args[:result]
if not args[:users].include? self.login #prevent duplicates
result.merge!({:user => {:id => self.id,
:login => self.login,
:role => self.role,
:employees => employee_tree(args[:users] + [self.login], args[:result])
}
})
end
logger.info result.inspect
return result
end
def employee_tree(users, result)
if self.employees.length > 0
self.employees.each {|emp| (emp.management_tree({:users => users, :result => result})) }
end
return result
end
Now... it's supposed to return something like this:
{:user=>{:login=>"me", :id=>1, :role=>2,
:employees=>{
:user => {:login => "2", ...},
:user => {:login => "3",
:employees => {...}
}
}}
Some console output:
% bundle exec script/console
Loading development environment (Rails 2.3.8)
>> require "awesome_print"
=> []
>> ap User.find(1).management_tree[:employees]
nil
=> nil
>> ap User.find(1).management_tree
{
:user => {
:employees => {...},
:role => 2,
:login => "me",
:id => 1
}
}
=> {:user=>{:employees=>{...}, :role=>2, :login=>"me", :id=>1}}
>>
now... it says that employees is nil... but it shouldn't be... it should have 3 hashes ... =\
but also, what does {...} mean? it seams terribly ambiguous
Ruby is clever about recursive structures and will use "..." instead of looping indefinitely.
For example:
a = [1, 2]
a << a # a is now recursive, since it contains itself
a.to_s # => [1, 2, [...]]
a[2][2][2][2][2][2][2] == a # => true
In your case, the {...} refers to any of the hashes already in the process of being outputed.
Maybe what you meant to do was to insert a copy of a hash? In the simple array example:
a = [1, 2]
a << a.dup # a is not recursive
a.to_s # => [1, 2, [1, 2]]

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