How can I pass an array as an argument to a Rake task?

I'm writing a Rake task and I want to pass an array as one of the arguments. Here's how I currently have it.

task :change_statuses, :ids, :current_status, :new_status do |task, args|
  puts "args were #{args.inspect}"
end

I've tried running the task these ways:

# First argument as array
rake "change_statuses[[1,2,3], active, inactive]"

# First argument as string
rake "utility:change_account_statuses['1,2,3', foo, bar]"

My expected output would be:

args were {:ids=> [1,2,3], :current_status=> 2 , :new_status=> 3}

However, my actual output in each case is:

args were {:ids=>"[1", :current_status=>"2", :new_status=>"3]"}

How can I pass an array to a Rake task?

One of the soulutions is to avoid , symbol in the string, so your command line would look like:

$ rake change_statuses['1 2 3', foo, bar]

Then you can simply split the IDs:

# Rakefile

task :change_statuses, :ids, :current_status, :new_status do |task, args|
  ids = args[:ids].split ' '

  puts "args were #{args.inspect}"
  puts "ids were #{ids.inspect}"
end

Or you can parse the ids value to get your expected output:

args[:ids] = args[:ids].split(' ').map{ |s| s.to_i }

I'm using rake 0.8.7

4 Ways to Pass Arguments to a Rake Task, Always googling and forgetting how to pass arguments to rake tasks? Here's a up list of the various methods. To call this task from the command line, pass it the arguments in []s. rake task_name['Hello',4] will output. Hello Hello Hello Hello and if you want to call this task from another task, and pass it arguments, use invoke. task :caller do puts 'In Caller' Rake::Task[:task_name].invoke('hi',2) end then the command. rake caller will output. In

rake "change_statuses[1 2 3, foo, bar]"

this works for me, you should not quota 1 2 3 with '

task :import_course, [:cids, :title] => :environment do |t, args|
  puts args[:cids]
end

if you quota 1 2 3 as the correct answer, args[:cids] will be "'1 2 3'", which ' char included, you have to trim ' char, but if you use my answer, args[:cids] will be "1 2 3", which is more easy to use, you just need args[:cids].split(" ") to get [1, 2, 3]

Rake: Task Arguments � Jacob Swanner, There are times when we want to pass variable data to our tasks; You declare task arguments with an Array as the second parameter to the� If you want to pass a single-dimension array as an argument in a function, you would have to declare a formal parameter in one of following three ways and all three declaration methods produce similar results because each tells the compiler that an integer pointer is going to be received.

You can do this as an alternative:

 task :my_task, [:values] do |_task, args|
   values = args.values.split(',')
   puts values
 end

and run the task using

rake my_task"[1\,2\,3]"

How to pass array parameters to rake tasks using comma?, rake task1 IDS=1,2,3. or. rake task1 IDS=1. However, if we pass the parameters. task :task2, [:batch_ids] => :environment => do |t, args|. 7.3 Passing Array as Parameters to Methods . Just like other objects, arrays can be passed as parameters to methods. The following method takes a int array as an argument and prints the data stored in each element of array:

Another way to achieve this and also win the ability to pass a hash

namespace :stackoverflow do
  desc "How to pass an array and also a hash at the same time 8-D"
  task :awesome_task, [:great_attributes] do |task, args|
    options = Rack::Utils.parse_nested_query(args[:attributes])
    puts option
  end
end

And just call the rake task like this:

bundle exec rake "player_rules:awesome_task[what_a_great_key[]=I know&what_a_great_key[]=Me too\!&i_am_a_hash[and_i_am_your_key]=what_an_idiot]"

And that will print

{"what_a_great_key"=>["I know", "Me too!"], "i_am_a_hash"=>{"and_i_am_your_key"=>"what_an_idiot"}}

How To Use Arguments In a Rake Task, You can write Rake tasks that accept arguments, called like this: rake tweets: send[cpytel]. You define the rask task like this: namespace :tweets� Now when I invoke this task with a parameter, the args hash will contain :response as the key and the value I supply to the parameter: $ rake call[Task] When I say Rake, you say 'Task'! Rake! Task! However, the argument is not required so I get some strange results when I don't provide one. I can fix that quickly by setting a default value:

ruby on rails, Hello. In Rails3, I am creating a batch using the rake task. I want to pass an array as an argument when calling a task. One can pass the 1-D arrays to a method. There are various options like first, you declare and initialize the array separately then pass it to the method. Second, you can declare, initialize and pass the array to the method in a single line of code. Example 1: Declaring and initializing array first and then pass it to the method as an argument.

Rake Task With an Arbitrary Number of Arguments, How to create a rake task that accepts any number of parameters, instead of just You could use an alternative method of passing arguments in, such as to an #extras method that will return an array of any extra arguments. Rake is beautiful tool, helping automate many tasks using Ruby. When You want to pass some arguments You can add VAR=value on command line and then in task use ENV['VAR'] to access passed value. But it is not what You alway want. Sometimes You want more compact and clean way to pass arguments. Starting with Rake 0.8.0 You can create tasks with

Passing Arguments To A Rake Task, You can create a rake task that takes arguments by including an array of named arguments in the task declaration. task :greeting, [:name] do |task,� If you want to pass an array into a variadic function. You can use ES6 spread to turn that array into a list of arguments. Yay, so much cleaner and no useless null from the old apply way 👏

Comments
  • I know I can use ENV for this, but I want to know if there's a more idiomatic way.
  • Note that when invoking a rake task with params, there should be no spaces after commas, else bash will misinterpret it and you'll get an error like Don't know how to build task blahblah[param,'. So the example above should read rake change_statuses['1 2 3',foo,bar]
  • Thanks, Linus! Strange :) It really looks like a bash trick, but I remember I was testing it before posting the answer. The another approach to solve that problem is to put rake task into braces so the example will look like rake "change_statuses['1 2 3', foo, bar]".
  • That works fine at the console, too, but I've gotten bitten when trying to run on heroku with both our suggestions. :) In the end, I had to type the equivalent of heroku run rake "change_statuses['1 2 3',foo,bar]", since the outer quotes were dropped!
  • Thank you Linus for your comment! Could not figure out why calling a task from the command line with multiple arguments was giving me this error "Don't know how to build task..." but you pointed me in the right (and simple) direction.
  • You have quoted the entire rake task, I think rake change_status['1 2 3', foo bar] is more appropriate.
  • have you tried? please try, rake change_status['1 2 3', foo bar], pass '1 2 3' as string, but include ', "'1 2 3'", you have to trim ' char, rake change_status['1 2 3', foo bar] pass [1, 2, 3] as string without ' char included, which is more easy to use, you just need to split(" ") to get array