Initial commit.

master
Luka Vandervelden 2019-06-08 02:21:31 +02:00
commit 2dd3fe7dd6
1 changed files with 413 additions and 0 deletions

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src/main.cr Normal file
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require "option_parser"
require "yaml"
# TODO:
# - Be more declarative about the definition of commands.
def split_command(string)
args = string.split /\ (?=([^\"]*\"[^\"]*\")*[^\"]*$)/
command = args[0]
args.delete_at 0
return command, args
end
class ServiceDefinition
struct Consumes
YAML.mapping({
token: String,
optional: {
type: Bool,
default: false
}
})
end
struct Provides
YAML.mapping({
token: String
})
end
YAML.mapping({
name: String,
command: String,
stop_command: {
type: String?,
key: "stop-command"
},
directory: String?, # Place to chdir to before running @command.
environment: {
type: Environment,
default: Environment.root
},
provides: {
type: Array(Provides),
default: [] of Provides
},
consumes: {
type: Array(Consumes),
default: [] of Consumes
}
})
def self.new(name)
Service.from_yaml File.read "#{name}.yaml"
end
class_getter all = [] of ServiceDefinition
def self.load(path)
Dir.each_child path do |child|
unless child.match /\.yaml$/
next
end
@@all << ServiceDefinition.from_yaml File.read "#{path}/#{child}"
end
end
def self.get(name) : ServiceDefinition
_def = @@all.find &.name.==(name)
if _def.nil?
raise Exception.new "Service '#{name}' does not exist."
end
_def
end
def to_s
name
end
end
class Environment
enum Type
Native
RootFileSystem
end
YAML.mapping({
name: String,
type: {
type: Type,
default: Type::Native
},
domain_name: {
type: String?,
key: "domain-name"
}
})
def initialize()
@name = "root"
@type = Type::Native
end
class_getter root = Environment.new
class_getter all = [@@root] of Environment
def self.load(path)
Dir.each_child path do |child|
unless child.match /\.yaml$/
next
end
@@all << Environment.from_yaml File.read "#{path}/#{child}"
end
end
def self.get(name)
_def = @@all.find &.name.==(name)
if _def.nil?
raise Exception.new "Environment '#{name}' does not exist."
end
_def
end
def to_s
"#{name} (#{type.to_s.downcase})"
end
end
class Service
getter environment : Environment
getter providers = ProvidersList.new
class ProvidersList < Hash(String, String)
def []?(name)
super(name).try { |x| Service.get_by_id x}
end
end
struct AsYAML
YAML.mapping({
name: String,
environment: String,
consumes: {
type: Array(YAMLConsumes),
default: [] of YAMLConsumes
}
})
end
struct YAMLConsumes
YAML.mapping({
token: String,
from: String
})
end
def initialize(name, environment_name : String?, @consumes = [] of YAMLConsumes)
@reference = ServiceDefinition.get name
@environment = if environment_name.nil? || environment_name == ""
Environment.root
else
Environment.get environment_name
end
consumes.map do |consume|
@providers[consume.token] = consume.from
end
end
def self.from_yaml(yaml)
yaml = AsYAML.from_yaml yaml
self.new yaml.name, yaml.environment, yaml.consumes
end
def to_yaml
{
name: name,
environment: @environment.name
}.to_yaml
end
# FIXME: At this point, macros would be both more readable and shorter.
def name
@reference.name
end
def type
@reference.type
end
def command
@reference.command
end
def stop_command
@reference.stop_command
end
def provides
@reference.provides
end
def start(log_dir : String)
command, args = split_command command
process = Process.fork do
base_log_name = "#{log_dir}/#{name}.#{@environment.name}"
stdout_file = File.open "#{base_log_name}.out", "w"
stderr_file = File.open "#{base_log_name}.err", "w"
LibC.dup2 stdout_file.fd, 1
LibC.dup2 stderr_file.fd, 2
Process.exec command, args, chdir: @reference.directory
end
self.pid = process.pid
end
# TODO:
# - Custom shutdown commands.
# - Should we wait for the process to die?
def stop
_pid = pid
if _pid
command = stop_command
if command
command, args = split_command command
Process.run(command, args)
else
Process.kill Signal::TERM, _pid
end
else
# Already stopped or dead, nothing to be done here.
end
end
def get_pid_file
"#{name}.pid"
end
def pid
File.read(get_pid_file).to_i
rescue e # pid file missing, corrupted or otherwise not readable
nil
end
def pid=(new_pid)
File.write get_pid_file, new_pid
end
enum Status
Running
Dead
Stopped
end
def status
_pid = pid
if _pid
if Process.exists? _pid
Status::Running
else
Status::Dead
end
else
Status::Stopped
end
end
def to_s
"#{name} (in #{@environment.name})"
end
def summary
"Name: #{name}\n" +
"Environment: #{environment.name} (#{environment.type.to_s.downcase})\n" +
"Provides:\n" +
(provides.map { |x| " - " + x.token + "\n" }).join +
"Consumes:\n" +
(@reference.consumes.map { |x|
provider = @providers[x.token]?
if provider
" - #{x.token} (from #{provider.to_s})\n"
else
" - #{x.token} (NOT CURRENTLY PROVIDED)\n"
end
}).join
end
class_getter all = [] of Service
def self.load(path)
Dir.each_child path do |child|
unless child.match /\.yaml$/
next
end
@@all << Service.from_yaml File.read "#{path}/#{child}"
end
end
def write(path)
File.write "#{path}/#{name}.#{@environment.name}.yaml", to_yaml
end
def remove(path)
File.delete "#{path}/#{name}.#{@environment.name}.yaml"
end
def self.get_by_id(id)
matches = id.match /[^\/]*/
unless matches
raise Exception.new "FIXME"
end
environment_name = matches[0]
service_name = id.sub 0..matches[0].size, ""
@@all.find do |service|
service.name == service_name
end
end
end
args = [] of String
parser = OptionParser.parse! do |parser|
parser.banner = "usage: yunoservice <command> [options]\n" +
"\n" +
"commands:\n" +
" start\n" +
" stop\n" +
" status\n" +
" show\n" +
" add\n" +
" del\n" +
" list\n" +
" list-environments\n" +
"\n" +
"options:\n"
parser.on "-h", "--help", "Prints this help message." do
puts parser
exit 0
end
parser.unknown_args do |x|
args = x
end
end
command = args[0]?
if command.nil?
STDERR << parser << "\n"
exit 1
end
ServiceDefinition.load "services"
Environment.load "environments"
Service.load "rc"
begin
if args[0] == "help"
puts parser
elsif args[0] == "add"
Service.new(args[1], args[2]?).write "rc"
elsif args[0] == "del"
Service.new(args[1], args[2]?).remove "rc"
elsif args[0] == "start"
Service.new(args[1], args[2]?).start "log"
elsif args[0] == "stop"
Service.new(args[1], args[2]?).stop
elsif args[0] == "status"
puts Service.new(args[1], args[2]?).status
elsif args[0] == "show"
service = Service.all.find do |service|
unless service.name == args[1]
next false
end
env = args[2]? || "root"
if service.environment.name != env
next false
end
true
end
if service
puts service.summary
else
STDERR << "No such service is registered.\n"
exit 2
end
elsif args[0] == "list"
Service.all.map do |service|
puts service.to_s
end
elsif args[0] == "list-environments"
Environment.all.map do |env|
puts env.to_s
end
else
STDERR << parser << "\n"
exit 1
end
rescue e
STDERR << e.message << "\n"
exit 2
end