How to insert an array to an existing hash array in Ruby? - ruby-on-rails

I have a current array of the below hash map, i have another array that i would like to insert into each hash by matching on the id.
{"url"=>"http://ubuntu64:1990/getpages",
"id"=>"32794",
"version"=>"2",
"title"=>"Creating a page",
"space"=>"test",
"parentId"=>"32782",
"permissions"=>"0"}
The other array i want to add the 'imageurl' key/value based on the id, so something like (if id == id insert 'imageurl'/'someurl.jpg}
{"id"=>"32794", "imageurl" => "someurl.jpg}

array = [...] #Declare your array with the "big" hashes here
array2 = [...] #Declare your array with the hash containing the imageurl key here
array.each do |a|
array2.each do |a2|
if a[:id] == a2[:id]
a[:imageurl] = a2[:imageurl]
break #We found it
end
end
end
Should do the trick ... maybe there's a smarter way to do it though

Related

how to concat string to array element in rails

I have an array as
["first_name"]
and I want to convert it to
["user.first_name"]
I cannot figure out how I can do this in rails.
If you would like to append text to the values you have in a array you're going to probably want to loop through the data and append to each element in the array like so:
my_array = ["test", "test2", "first_name"]
new_array = my_array.collect{|value| "user.#{value}" }
new_array will now be:
["user.test", "user.test2", "user.first_name"]
You could also just overwrite your original array by using collect! like so
my_array = ["test", "test2", "first_name"]
my_array.collect!{|value| "user.#{value}" }
This will of course overwrite your original original data in my_array
If you would like to just change one value in the array you could use the index of that array and assign the value
my_array = ["test", "test2", "first_name"]
my_array[1] = "user.#{my_array[1]}}
my_array will now read:
["test", "user.test2", "first_name"]
Supposing you've multiple elements in your array, I recommend using .map.
It allows you to iterate the array elements, and return a new value for each of them.
%w[first_name last_name email].map do |attr|
"user.#{attr}"
end
# => [user.first_name, user.last_name, user.email]

how to check if a certain key-value pair exists in array of hashes as json in ruby on rails

I have an array of hashes as json, so how to check my array of hashes contains a hash with a given key-value pair.
This is my json
[{"question"=>"0a2a3452", "answer"=>"bull"}, {"question"=>"58deacf9", "answer"=>"bullafolo"}, {"question"=>"32c53e5f", "answer"=>"curosit"}, {"question"=>"b5546bcf", "answer"=>""}, {"question"=>"0f0b314", "answer"=>""}]
I tried looping through the json array, but this is tedious, as I need to check that if that json has that hash with a given key-value pair
It's a questionnaire form, in which I have to perform an update on answers
if !#client_find.nil?
#client_find.questionnaire
params[:commit].each do |key, value|
#json=[]
#json = #client_find.questionnaire
if !value.empty? && #json.include?(key)
puts "blunderc "+ value.inspect
#new_append = Hash.new
#new_append[:question] = key
#new_append[:answer]= value
#json << #new_append
end
if !key.empty? && !value.empty?
#logic
#json.each do |u|
if (u.key? key)
puts "bothu "+ u[key].inspect
u[key] = value
end
end
end
end
Array#any? iterates through the array. In each iteration I check wether the current hash has the searched question key or not. If a hash is found Array#any? returns true otherwise false.
array = [{"question"=>"0a2a3452", "answer"=>"bull"}, {"question"=>"58deacf9", "answer"=>"bullafolo"}, {"question"=>"32c53e5f", "answer"=>"curosit"}, {"question"=>"b5546bcf", "answer"=>""}, {"question"=>"0f0b314", "answer"=>""}]
search_for_key = '0a2a3452'
array.any?{|hash| hash['question'] == search_for_key}
I'll assume that you want to check the existence of a hash which has the key/value pair "quesetion" => "some-value".
Here's how you can do it:
array.any? { |item| item['question'] == 'some-question-id' }
Considering your are checking for a particular key exists or not
#json.any? {|obj| obj.key?(your_particular_key)
You can filter the array using Enumerable#select to get only the hashes that contains the desired key.
filtered = my_hash.select { |item| item['desired_key'] }
That's possible because nil is falsey. If you input is a raw JSON you'll need to parse it to a Ruby hash using JSON#parse or any other equivalent method.
filtered will give you all the hashes that contain the desired_key.
Is that what you want ?
Btw guitarman's answer is way better !
questions = [{"question"=>"0a2a3452", "answer"=>"bull"}, {"question"=>"58deacf9", "answer"=>"bullafolo"}, {"question"=>"32c53e5f", "answer"=>"curosit"}, {"question"=>"b5546bcf", "answer"=>""}, {"question"=>"0f0b314", "answer"=>""}]
result = questions.find { |question| question['question'] == "Bonour" }
if result.nil?
puts "Not found"
else
puts "#{result['question']} #{result['answer']}"
end

Splitting values in Hash

I have a Hash in the following format:
{"PPS_Id"=>["fe4d7c06-215a-48a7-966d-19ab58976548", "6e90208e-4ab2-4d44-bbaa-9a874bff095b"], "Amount"=>"[\"10000.000\", \"2374.000\"]"}
When I write this data into an excel get the following output.
I want to write the data into the Excel this way:
PPS_Id Amount
fe4d7c06-215a-48a7-966d-19ab58976548 10000.000
6e90208e-4ab2-4d44-bbaa-9a874bff095b 2374.000
How do I convert my current Hash to the below?
{PPS_Id"=>["fe4d7c06-215a-48a7-966d-19ab58976548","Amount"=>"10000.000"},{PPS_Id"=>["6e90208e-4ab2-4d44-bbaa-9a874bff095b","Amount"=>"2374.000"}
Can you please assist.
If you can modify your original hash from
hash = {"PPS_Id"=>["fe4d7c06-215a-48a7-966d-19ab58976548", "6e90208e-4ab2-4d44-bbaa-9a874bff095b"], "Amount"=>"[\"10000.000\", \"2374.000\"]"}
to
hash = {"PPS_Id"=>["fe4d7c06-215a-48a7-966d-19ab58976548", "6e90208e-4ab2-4d44-bbaa-9a874bff095b"], "Amount"=>["10000.000", "2374.000"]}
Note: the last value in the hash is an Array instead of a String.
Then, you can generate an Array of hashes on which you can iterate to fill your excel:
ary = hash.inject([]) do |r, (key, value)|
value.each_with_index do |e, i|
r[i] ||= {}
r[i][key] = e
end
r
end
ary # [{"PPS_Id"=>"fe4d7c06-215a-48a7-966d-19ab58976548", "Amount"=>"10000.000"}, {"PPS_Id"=>"6e90208e-4ab2-4d44-bbaa-9a874bff095b", "Amount"=>"2374.000"}]
If your hash really looks like this :
hash = {"PPS_Id"=>["fe4d7c06-215a-48a7-966d-19ab58976548", "6e90208e-4ab2-4d44-bbaa-9a874bff095b"],
"Amount"=>"[\"10000.000\", \"2374.000\"]"}
you can use scan to parse the floats first :
hash["Amount"] = hash["Amount"].scan(/[\d\-\.]+/)
Your hash will now look like :
{"PPS_Id"=>["fe4d7c06-215a-48a7-966d-19ab58976548", "6e90208e-4ab2-4d44-bbaa-9a874bff095b"],
"Amount"=>["10000.000", "2374.000"]}
To get the table you want, you could just transpose the hash values :
hash.values_at("PPS_Id", "Amount").transpose.each{|id, amount|
puts format("%s\t%.3f", id, amount)
}
It will output :
fe4d7c06-215a-48a7-966d-19ab58976548 10000.000
6e90208e-4ab2-4d44-bbaa-9a874bff095b 2374.000

Searching array of objects for item in Ruby

I am trying to search through an array of objects for a value, but am having trouble getting the find_index to work. In my code below, I am trying to search for the name (joseph) in the array. Is this the best way? I want to return that object after I search and find it.
name = "joseph"
array = [{"login":"joseph","id":4,"url":"localhost/joe","description":null},
{"login":"billy","id":10,"url":"localhost/billy","description":null}]
arrayItem = array.find_index {|item| item.login == name}
puts arrayItem
Your array contains a Hash, with keys that are symbols (in hashes, key: value is a shorthand for :key => value). Therefore, you need to replace item.login with item[:login]:
name = "joseph"
array = [{"login":"joseph","id":4,"url":"localhost/joe","description":nil},
{"login":"billy","id":10,"url":"localhost/billy","description":nil}]
arrayIndex = array.find_index{ |item| item[:login] == name }
puts arrayIndex
The code above retrieves the index at which the sought object is in the array. If you want the object and not the index, use find instead of find_index:
arrayItem = array.find{ |item| item[:login] == name }
Also, note that in Ruby, null is actually called nil.

Split an Array of arrays into 2 separate arrays in Ruby

I have a hash with some key value pairs as below:
#level2 = #l2.inject(Hash.new(0)) { |hash,element|
hash[element] +=1
hash }
I perform some sorting on the hash based on the keys.
#level2 = #level2.sort_by { |x, _| x }.reverse
Now I assume that the sort_by gives me an Array of Arrays. I want to split this into 2 arrays such that my first array should contain all keys and second array should contain all values.
The hash#keys and hash#values are not accessible after sorting the hash. So that does not work in this case.
Regardless of how you make the hash it will will have a Hash#keys method and a Hash#values. They both return arrays that are just what you seem to want.
keys_array = #level2.keys
values_array = #level2.values
You could iterate over the array of arrays and add each element to a new array. This would keep the order of the elements.
keys_array = []
values_array = []
#level2.each do |key, value|
keys_array << key
values_array << value
end

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