Class: OsCtld::EtcHosts
- Inherits:
-
Object
- Object
- OsCtld::EtcHosts
- Includes:
- OsCtl::Lib::Utils::File
- Defined in:
- lib/osctld/etc_hosts.rb
Overview
Manipulate localhost hostnames in `/etc/hosts` like files
Instance Attribute Summary collapse
- #path ⇒ String readonly
Instance Method Summary collapse
-
#add_name(line, name, after: nil) ⇒ Object
protected
Add hostname to `line` from `/etc/hosts`.
-
#all_names(hostname) ⇒ Object
protected
Return all names in the order that should be set for a hostname.
-
#do_edit(names) ⇒ Object
protected
Edit the hosts file and let the caller transform it.
-
#includes_name?(line, name) ⇒ Boolean
protected
Check if a line of string contains specific hostname.
-
#initialize(path) ⇒ EtcHosts
constructor
A new instance of EtcHosts.
- #replace(old_hostname, new_hostname) ⇒ Object
-
#replace_name(line, old_name, new_name) ⇒ Object
protected
Replace hostname in `line` read from `/etc/hosts`.
- #set(hostname) ⇒ Object
- #zip_all(a, b) ⇒ Object protected
Constructor Details
#initialize(path) ⇒ EtcHosts
Returns a new instance of EtcHosts.
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# File 'lib/osctld/etc_hosts.rb', line 12 def initialize(path) @path = path end |
Instance Attribute Details
#path ⇒ String (readonly)
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# File 'lib/osctld/etc_hosts.rb', line 9 def path @path end |
Instance Method Details
#add_name(line, name, after: nil) ⇒ Object (protected)
Add hostname to `line` from `/etc/hosts`
The hostname is put into the first position.
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# File 'lib/osctld/etc_hosts.rb', line 121 def add_name(line, name, after: nil) if after replace_name(line, after, "#{after} #{name}") else return if line !~ /^([^\s]+)(\s+)/ i = $~.end(2) "#{$1}#{$2}#{name} #{line[i..-1]}" end end |
#all_names(hostname) ⇒ Object (protected)
Return all names in the order that should be set for a hostname
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# File 'lib/osctld/etc_hosts.rb', line 95 def all_names(hostname) ret = [] if hostname.local == hostname.fqdn ret << hostname.fqdn else ret << hostname.fqdn << hostname.local end ret end |
#do_edit(names) ⇒ Object (protected)
Edit the hosts file and let the caller transform it
If the target file exists, it is read and each line is yielded to the caller. The caller returns the new value that is written to the target file instead of the original line.
If the target file does not exist, it is created and populated with `names`. Nothing is yielded to the caller in that case.
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# File 'lib/osctld/etc_hosts.rb', line 76 def do_edit(names) regenerate_file(path, 0644) do |new, old| if old old.each_line do |line| new.write(yield(line)) end else new.write(<<END 127.0.0.1 #{(names + %w(localhost)).join(' ')} ::1 #{(names + %w(localhost ip6-localhost ip6-loopback)).join(' ')} END ) end end end |
#includes_name?(line, name) ⇒ Boolean (protected)
Check if a line of string contains specific hostname
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# File 'lib/osctld/etc_hosts.rb', line 110 def includes_name?(line, name) /\s#{Regexp.escape(name)}(\s|$)/ =~ line end |
#replace(old_hostname, new_hostname) ⇒ Object
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# File 'lib/osctld/etc_hosts.rb', line 40 def replace(old_hostname, new_hostname) old_names = all_names(old_hostname) new_names = all_names(new_hostname) do_edit(new_names) do |line| next(line) if (/^127\.0\.0\.1\s/ !~ line && /^::1\s/ !~ line) new_line = line.strip last = nil zip_all(new_names, old_names).each do |new_name, old_name| if old_name && includes_name?(new_line, old_name) new_line = replace_name(new_line, old_name, new_name || '') elsif new_name new_line = add_name(new_line, new_name, after: last) end last = new_name end new_line << "\n" new_line end end |
#replace_name(line, old_name, new_name) ⇒ Object (protected)
Replace hostname in `line` read from `/etc/hosts`
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# File 'lib/osctld/etc_hosts.rb', line 137 def replace_name(line, old_name, new_name) line.sub( /(\s)#{Regexp.escape(old_name)}(\s|$)/, "\\1#{new_name}\\2" ) end |
#set(hostname) ⇒ Object
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# File 'lib/osctld/etc_hosts.rb', line 17 def set(hostname) names = all_names(hostname) do_edit(names) do |line| next(line) if (/^127\.0\.0\.1\s/ !~ line && /^::1\s/ !~ line) new_line = line.strip last = nil names.each do |name| next if includes_name?(new_line, name) new_line = add_name(new_line, name, after: last) last = name end new_line << "\n" new_line end end |
#zip_all(a, b) ⇒ Object (protected)
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# File 'lib/osctld/etc_hosts.rb', line 144 def zip_all(a, b) [a.size, b.size].max.times.map { |i| [a[i], b[i]] } end |