Use controller method in ActionCable channel - ruby

Question

I have a rails api that I am trying to create a live stream feature for a git gui. I have a controller and a channel for commit updates and I want to use the live stream function inside the subscribe action in the channel. Is this possible? Or is there a better Rails way to do this. I think the correct way was to use ActionCable.server.broadcast('commit_updates', { body: return_data }) inside my controller method but I am not calling my controller method anywhere. Where/how do I call it so that it is run on a client subscribing to it? or should I place the logic inside the channel?
here is my commit_updates_controller.rb
class CommitUpdatesController < ApplicationController
include ActionController::Live
require 'listen'
require 'json'
$file_path = "#{Dir.getwd}/.git/objects"
##commits = {}
##commits_array = []
##edges_array = []
def index
end
def live_stream
# get folders exlcluding ".","..", "pack","info"
folders = Dir.entries($file_path).select {|folder| /^[a-z0-9]{2}$/i.match(folder) }
folders.each do |folder|
files = Dir.children("#{$file_path}/#{folder}")
files.each do |file|
CommitUpdate.find_commit_info(folder, file, ##commits_array)
end
end
generate_edges
ActionCable.server.broadcast('commit_updates', { body: return_data })
p return_data
# listens to any changes that happen to the git folder while the program is open
listener = Listen.to($file_path) do |modified, added, removed|
# puts(modified: modified, added: added, removed: removed)
added.each do |new_file_path|
split_new_file_path = new_file_path.split("/").reject!{|item| item.empty?}
folder = split_new_file_path[split_new_file_path.length() - 2]
file = split_new_file_path[split_new_file_path.length - 1]
CommitUpdate.find_commit_info(folder, file, ##commits_array)
add_edge(##edges_array, CommitUpdate.get_commit_info(folder, file))
ActionCable.server.broadcast('commit_updates', { body: return_data })
end
end
listener.start
sleep
end
private
def generate_edges
if ##commits_array.length != 0
##commits_array.each do |commit|
add_edge(##commits_array, commit)
end
end
end
def add_edge(array, commit)
if commit[:parents] != []
commit[:parents].each {|parent| ##edges_array.push({from: parent, to: commit[:sha1]})}
end
end
def return_data
ret = {
:nodes => ##commits_array,
:links => ##edges_array
}
return ret.to_json
end
end
here is my commit_updates_channel.rb
class CommitUpdatesChannel < ApplicationCable::Channel
def subscribed
stream_from 'commit_updates'
end
end
here is my commit_updates.rb Model
class CommitUpdate < ApplicationRecord
def self.find_commit_info(folder, file, array)
file_type = self.check_sha1_type(folder, file)
if file_type == "commit"
array.push(
self.get_commit_info(folder, file)
)
end
end
def self.get_commit_info(folder, file)
author = ""
parents = []
commit_message = ""
unixtime = ""
decoded_file = `git cat-file -p #{folder}#{file}`
file_data_array = decoded_file.split("\n").reject!{|item| item.empty?}
p file_data_array
file_data_array.each do |item|
split_item = item.split(" ")
case split_item[0]
when "author"
author = split_item[1..split_item.length() - 4].join(" ")
when "parent"
parents.push(split_item[1])
when "tree"
next
when "blob"
next
when "committer"
unixtime = split_item[split_item.length - 2]
else
commit_message = split_item.join(" ")
end
end
commit_info = {
:sha1 => "#{folder}#{file}",
:parents => parents,
:commit_message => commit_message,
:author => author,
:unixtime => unixtime,
:id => "#{folder}#{file}",
:label => "#{folder}#{file[0..4]}...",
:font => "18px verdana blue",
}
return commit_info
end
private
def self.check_sha1_type(folder, file)
return `git cat-file -t #{folder}#{file}`.chomp
end
end

Answer 1

To use controller's live_stream, you need to request this method, for example, write js programme that is calling it periodically. Or some bash script that is calling it. Not good.
Another solution is to put live_stream logic into background job that will check commit updates every X minute. And if job finds change, it broadcasts.
And more common is to place broadcasting in model callbacks after_save, after_commit. But it looks it is not your solution.