Say I have a hash like so:
top_billed = { ghostbusters: 'Bill Murray', star_wars: 'Harrison Ford' }
What would be the best way to format it in a nice, human-readable way?
For example if you called a method on the hash and it displayed the hash as a capitalized list, minus underscores.
"Ghostbusters: Bill Murray
Star Wars: Harrison Ford
I guess iterating over the array and using gsub to remove underscores then capitalizing might work, but I was wondering whether there was anything more elegant.
Thanks
Manually:
top_billed.each do |k, v|
puts k.to_s.gsub("_", " ") + ": " + v
end
if you are using Rails or ActiveSupport, you can also use the "humanize" method (on a String).
Here is a recursive solution:
top_billed = { ghostbusters: { my_name: 'Bill Murray', my_age: 29 }, star_wars: { my_name: 'Harrison Ford' }, something_esle: 'Its Name'}
def print_well(key, value, indent)
key = key.to_s.split('_').map(&:capitalize).join(' ')
if Hash === value
puts "#{key}: "
value.each do |k, v|
print_well k, v, indent + 1
end
else
puts "#{' '*indent}#{key}: #{value}"
end
end
def print_hash hash, indent=0
hash.each do |key, value|
print_well key, value, indent
end
end
print_hash top_billed
Related
I have a Hash which needs to be converted in a String with escaped characters.
{name: "fakename"}
and should end up like this:
'name:\'fakename\'
I don't know how this type of string is called. Maybe there is an already existing method, which I simply don't know...
At the end I would do something like this:
name = {name: "fakename"}
metadata = {}
metadata['foo'] = 'bar'
"#{name} AND #{metadata}"
which ends up in that:
'name:\'fakename\' AND metadata[\'foo\']:\'bar\''
Context: This query a requirement to search Stripe API: https://stripe.com/docs/api/customers/search
If possible I would use Stripe's gem.
In case you can't use it, this piece of code extracted from the gem should help you encode the query parameters.
require 'cgi'
# Copied from here: https://github.com/stripe/stripe-ruby/blob/a06b1477e7c28f299222de454fa387e53bfd2c66/lib/stripe/util.rb
class Util
def self.flatten_params(params, parent_key = nil)
result = []
# do not sort the final output because arrays (and arrays of hashes
# especially) can be order sensitive, but do sort incoming parameters
params.each do |key, value|
calculated_key = parent_key ? "#{parent_key}[#{key}]" : key.to_s
if value.is_a?(Hash)
result += flatten_params(value, calculated_key)
elsif value.is_a?(Array)
result += flatten_params_array(value, calculated_key)
else
result << [calculated_key, value]
end
end
result
end
def self.flatten_params_array(value, calculated_key)
result = []
value.each_with_index do |elem, i|
if elem.is_a?(Hash)
result += flatten_params(elem, "#{calculated_key}[#{i}]")
elsif elem.is_a?(Array)
result += flatten_params_array(elem, calculated_key)
else
result << ["#{calculated_key}[#{i}]", elem]
end
end
result
end
def self.url_encode(key)
CGI.escape(key.to_s).
# Don't use strict form encoding by changing the square bracket control
# characters back to their literals. This is fine by the server, and
# makes these parameter strings easier to read.
gsub("%5B", "[").gsub("%5D", "]")
end
end
params = { name: 'fakename', metadata: { foo: 'bar' } }
Util.flatten_params(params).map { |k, v| "#{Util.url_encode(k)}=#{Util.url_encode(v)}" }.join("&")
I use it now with that string, which works... Quite straigt forward:
"email:\'#{email}\'"
email = "test#test.com"
key = "foo"
value = "bar"
["email:\'#{email}\'", "metadata[\'#{key}\']:\'#{value}\'"].join(" AND ")
=> "email:'test#test.com' AND metadata['foo']:'bar'"
which is accepted by Stripe API
I want to take a hash with nested hashes and arrays and flatten it out into a single hash with unique values. I keep trying to approach this from different angles, but then I make it way more complex than it needs to be and get myself lost in what's happening.
Example Source Hash:
{
"Name" => "Kim Kones",
"License Number" => "54321",
"Details" => {
"Name" => "Kones, Kim",
"Licenses" => [
{
"License Type" => "PT",
"License Number" => "54321"
},
{
"License Type" => "Temp",
"License Number" => "T123"
},
{
"License Type" => "AP",
"License Number" => "A666",
"Expiration Date" => "12/31/2020"
}
]
}
}
Example Desired Hash:
{
"Name" => "Kim Kones",
"License Number" => "54321",
"Details_Name" => "Kones, Kim",
"Details_Licenses_1_License Type" => "PT",
"Details_Licenses_1_License Number" => "54321",
"Details_Licenses_2_License Type" => "Temp",
"Details_Licenses_2_License Number" => "T123",
"Details_Licenses_3_License Type" => "AP",
"Details_Licenses_3_License Number" => "A666",
"Details_Licenses_3_Expiration Date" => "12/31/2020"
}
For what it's worth, here's my most recent attempt before giving up.
def flattify(hashy)
temp = {}
hashy.each do |key, val|
if val.is_a? String
temp["#{key}"] = val
elsif val.is_a? Hash
temp.merge(rename val, key, "")
elsif val.is_a? Array
temp["#{key}"] = enumerate val, key
else
end
print "=> #{temp}\n"
end
return temp
end
def rename (hashy, str, n)
temp = {}
hashy.each do |key, val|
if val.is_a? String
temp["#{key}#{n}"] = val
elsif val.is_a? Hash
val.each do |k, v|
temp["#{key}_#{k}#{n}"] = v
end
elsif val.is_a? Array
temp["#{key}"] = enumerate val, key
else
end
end
return flattify temp
end
def enumerate (ary, str)
temp = {}
i = 1
ary.each do |x|
temp["#{str}#{i}"] = x
i += 1
end
return flattify temp
end
Interesting question!
Theory
Here's a recursive method to parse your data.
It keeps track of which keys and indices it has found.
It appends them in a tmp array.
Once a leaf object has been found, it gets written in a hash as value, with a joined tmp as key.
This small hash then gets recursively merged back to the main hash.
Code
def recursive_parsing(object, tmp = [])
case object
when Array
object.each.with_index(1).with_object({}) do |(element, i), result|
result.merge! recursive_parsing(element, tmp + [i])
end
when Hash
object.each_with_object({}) do |(key, value), result|
result.merge! recursive_parsing(value, tmp + [key])
end
else
{ tmp.join('_') => object }
end
end
As an example:
require 'pp'
pp recursive_parsing(data)
# {"Name"=>"Kim Kones",
# "License Number"=>"54321",
# "Details_Name"=>"Kones, Kim",
# "Details_Licenses_1_License Type"=>"PT",
# "Details_Licenses_1_License Number"=>"54321",
# "Details_Licenses_2_License Type"=>"Temp",
# "Details_Licenses_2_License Number"=>"T123",
# "Details_Licenses_3_License Type"=>"AP",
# "Details_Licenses_3_License Number"=>"A666",
# "Details_Licenses_3_Expiration Date"=>"12/31/2020"}
Debugging
Here's a modified version with old-school debugging. It might help you understand what's going on:
def recursive_parsing(object, tmp = [], indent="")
puts "#{indent}Parsing #{object.inspect}, with tmp=#{tmp.inspect}"
result = case object
when Array
puts "#{indent} It's an array! Let's parse every element:"
object.each_with_object({}).with_index(1) do |(element, result), i|
result.merge! recursive_parsing(element, tmp + [i], indent + " ")
end
when Hash
puts "#{indent} It's a hash! Let's parse every key,value pair:"
object.each_with_object({}) do |(key, value), result|
result.merge! recursive_parsing(value, tmp + [key], indent + " ")
end
else
puts "#{indent} It's a leaf! Let's return a hash"
{ tmp.join('_') => object }
end
puts "#{indent} Returning #{result.inspect}\n"
result
end
When called with recursive_parsing([{a: 'foo', b: 'bar'}, {c: 'baz'}]), it displays:
Parsing [{:a=>"foo", :b=>"bar"}, {:c=>"baz"}], with tmp=[]
It's an array! Let's parse every element:
Parsing {:a=>"foo", :b=>"bar"}, with tmp=[1]
It's a hash! Let's parse every key,value pair:
Parsing "foo", with tmp=[1, :a]
It's a leaf! Let's return a hash
Returning {"1_a"=>"foo"}
Parsing "bar", with tmp=[1, :b]
It's a leaf! Let's return a hash
Returning {"1_b"=>"bar"}
Returning {"1_a"=>"foo", "1_b"=>"bar"}
Parsing {:c=>"baz"}, with tmp=[2]
It's a hash! Let's parse every key,value pair:
Parsing "baz", with tmp=[2, :c]
It's a leaf! Let's return a hash
Returning {"2_c"=>"baz"}
Returning {"2_c"=>"baz"}
Returning {"1_a"=>"foo", "1_b"=>"bar", "2_c"=>"baz"}
Unlike the others, I have no love for each_with_object :-). But I do like passing a single result hash around so I don't have to merge and remerge hashes over and over again.
def flattify(value, result = {}, path = [])
case value
when Array
value.each.with_index(1) do |v, i|
flattify(v, result, path + [i])
end
when Hash
value.each do |k, v|
flattify(v, result, path + [k])
end
else
result[path.join("_")] = value
end
result
end
(Some details adopted from Eric, see comments)
Non-recursive approach, using BFS with an array as a queue. I keep the key-value pairs where the value isn't an array/hash, and push array/hash contents to the queue (with combined keys). Turning arrays into hashes (["a", "b"] ↦ {1=>"a", 2=>"b"}) as that felt neat.
def flattify(hash)
(q = hash.to_a).select { |key, value|
value = (1..value.size).zip(value).to_h if value.is_a? Array
!value.is_a?(Hash) || !value.each { |k, v| q << ["#{key}_#{k}", v] }
}.to_h
end
One thing I like about it is the nice combination of keys as "#{key}_#{k}". In my other solution, I could've also used a string path = '' and extended that with path + "_" + k, but that would've caused a leading underscore that I'd have to avoid or trim with extra code.
Suppose I have following hash or nested hash:
h = { :a1 => { :b1 => "c1" },
:a2 => { :b2 => "c2"},
:a3 => { :b3 => "c3"} }
I want to create a method that takes hash as a parameter and recursively convert all the keys (keys that are symbol eg. :a1) to String (eg. "a1"). So far I have come up with the following method which doesn't work and returns {"a1"=>{:b1=>"c1"}, "a2"=>{:b2=>"c2"}, "a3"=>{:b3=>"c3"}}.:
def stringify_all_keys(hash)
stringified_hash = {}
hash.each do |k, v|
stringified_hash[k.to_s] = v
if v.class == Hash
stringify_all_keys(stringified_hash[k.to_s])
end
end
stringified_hash
end
What am I doing wrong and how do a get all the keys converted to string like this:
{"a1"=>{"b1"=>"c1"}, "a2"=>{"b2"=>"c2"}, "a3"=>{"b3"=>"c3"}}
If you are using ActiveSupport already or are open to using it, then deep_stringify_keys is what you're looking for.
hash = { person: { name: 'Rob', age: '28' } }
hash.deep_stringify_keys
# => {"person"=>{"name"=>"Rob", "age"=>"28"}}
Quick'n'dirty if your values are basic objects like strings, numbers, etc:
require 'json'
JSON.parse(JSON.dump(hash))
Didn't test this, but looks about right:
def stringify_all_keys(hash)
stringified_hash = {}
hash.each do |k, v|
stringified_hash[k.to_s] = v.is_a?(Hash) ? stringify_all_keys(v) : v
end
stringified_hash
end
using plain ruby code, the below code could help.
you can monkey patched it to the ruby Hash, to use it like this my_hash.deeply_stringfy_keys
however, I do not recommend monkey batching ruby.
you can adjust the method to provide the deeply_strigify_keys! (bang) version of it.
in case you want to make a different method witch does not stringify recursively, or to control the level of stringifying then consider re-writing the below method logic so you can have it written better with considering the other variation mentioned above.
def deeply_stringify_keys(hash)
stringified_hash = {}
hash.each do |k, v|
if v.is_a?(Hash)
stringified_hash[k.to_s] = deeply_stringify_keys(v)
elsif v.is_a?(Array)
stringified_hash[k.to_s] = v.map {|i| i.is_a?(Hash)? deeply_stringify_keys(i) : i}
else
stringified_hash[k.to_s] = v
end
end
stringified_hash
end
In this code:
b = ["here", "are", "things"]
b.inject { |str, v| str+="#{v} " }
# => "hereare things "
shouldn't the return value be "here are things"? I assume it's passing the first value to the accumulator str. Is there a way to return "here are things "?
I'd assume it's passing in the first value to the accumulator
Correct, because initial value is not defined, first element of your collection becomes the initial value. Fix? Provide the initial value:
b = ['here', 'are', 'things']
b.inject('') { |memo, elem| memo + "#{elem} " } # => "here are things "
Add the space before the word, like this. This does not have trailing space in the result.
["here", "are", "things"].inject { |str, v| str+=" #{v}" }
#=> "here are things"
You could also do something like below and still not have trailing space
['here', 'are', 'things'].inject { |m, e| "#{m} #{e}" }
#=> "here are things"
I have an Array-1 say
arr1 =['s','a','sd','few','asdw','a','sdfeg']
And a second Array
arr2 = ['s','a','d','f','w']
I want to take arr1 and sort the frequency of letters by inputting arr2 with result
[s=> 4, a=> 2, d => 3] So on and so forth.
As far as I can muddle around.. Nothing below works, Just my thoughts on it?
hashy = Hash.new
print "give me a sentance "
sentance = gets.chomp.downcase.delete!(' ')
bing = sentance.split(//)
#how = sentance.gsub!(/[^a-z)]/, "") #Remove nil result
#chop = how.to_s.split(//).uniq
#hashy << bing.each{|e| how[e] }
#puts how.any? {|e| bing.count(e)}
#puts how, chop
bing.each {|v| hashy.store(v, hashy[v]+1 )}
puts bing
Thank you for your time.
I assumed that you want to count all letters in the sentence you put in, and not array 1. Assuming that, here's my take on it:
hashy = Hash.new()
['s','a','d','f','w'].each {|item| hashy[item.to_sym] = 0}
puts "give me a sentence"
sentence = gets.chomp.downcase.delete!(' ')
sentence_array = []
sentence.each_char do |l|
sentence_array.push(l)
end
hashy.each do |key, value|
puts "this is key: #{key} and value #{hashy[key]}"
sentence_array.each do |letter|
puts "letter: #{letter}"
if letter.to_sym == key
puts "letter #{letter} equals key #{key}"
value = value + 1
hashy[key] = value
puts "value is now #{value}"
end
end
end
puts hashy