module Beaker::Shared::HostManager
Methods for managing Hosts.
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selecting hosts by role (Symbol or String)
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selecting hosts by name (String)
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adding additional method definitions for selecting by role
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executing blocks of code against selected sets of hosts
Public Instance Methods
Source
# File lib/beaker/shared/host_manager.rb, line 59 def find_at_most_one_host_with_role(hosts, role) raise ArgumentError, "role cannot be nil." if role.nil? role_hosts = hosts_with_role(hosts, role) case role_hosts.length when 0 nil when 1 role_hosts[0] else host_string = (role_hosts.map { |host| host.name }).join(', ') raise ArgumentError, "There should be only one host with #{role} defined, but I found #{role_hosts.length} (#{host_string})" end end
Find at most a single host with the role provided. Raise an error if more than one host is found to have the provided role. @param [Array<Host>] hosts The hosts to examine @param [String] role The host returned will have this role in its role list @return [Host] The single host with the desired role in its roles list
or nil if no host is found
@raise [ArgumentError] Raised if more than one host has the given role defined,
or if role = nil since hosts_with_role(nil) returns all hosts.
Source
# File lib/beaker/shared/host_manager.rb, line 24 def hosts_with_name(hosts, name = nil) hosts.select do |host| name.nil? or host.name&.start_with?(name) or host[:vmhostname]&.start_with?(name) or host[:ip]&.start_with?(name) end end
Find hosts from a given array of hosts that all have the desired name, match against host name, vmhostname and ip (the three valid ways to identify an individual host) @param [Array<Host>] hosts The hosts to examine @param [String] name The hosts returned will have this name/vmhostname/ip @return [Array<Host>] The hosts that have the desired name/vmhostname/ip
Source
# File lib/beaker/shared/host_manager.rb, line 13 def hosts_with_role(hosts, desired_role = nil) hosts.select do |host| desired_role.nil? or host['roles'].include?(desired_role.to_s) end end
Find hosts from a given array of hosts that all have the desired role. @param [Array<Host>] hosts The hosts to examine @param [String] desired_role The hosts returned will have this role in their roles list @return [Array<Host>] The hosts that have the desired role in their roles list
Source
# File lib/beaker/shared/host_manager.rb, line 37 def only_host_with_role(hosts, role) raise ArgumentError, "role cannot be nil." if role.nil? a_host = hosts_with_role(hosts, role) if a_host.length == 0 raise ArgumentError, "There should be one host with #{role} defined!" elsif a_host.length > 1 host_string = (a_host.map { |host| host.name }).join(', ') raise ArgumentError, "There should be only one host with #{role} defined, but I found #{a_host.length} (#{host_string})" end a_host.first end
Find a single host with the role provided. Raise an error if more than one host is found to have the provided role. @param [Array<Host>] hosts The hosts to examine @param [String] role The host returned will have this role in its role list @return [Host] The single host with the desired role in its roles list @raise [ArgumentError] Raised if more than one host has the given role defined, if no host has the
role defined, or if role = nil since hosts_with_role(nil) returns all hosts.
Source
# File lib/beaker/shared/host_manager.rb, line 90 def run_block_on hosts = [], filter = nil, opts = {}, &block result = nil block_hosts = hosts # the hosts to apply the block to after any filtering if filter raise ArgumentError, "Unable to sort for #{filter} type hosts when provided with [] as Hosts" if hosts.empty? block_hosts = hosts_with_role(hosts, filter) # check by role if block_hosts.empty? block_hosts = hosts_with_name(hosts, filter) # check by name end block_hosts = block_hosts.pop if block_hosts.length == 1 # we only found one matching host, don't need it wrapped in an array end if block_hosts.is_a? Array if block_hosts.length > 0 if run_in_parallel? opts # Pass caller[1] - the line that called block_on - for logging purposes. result = block_hosts.map.each_in_parallel(caller(2..2).first) do |h| run_block_on h, &block end hosts.each { |host| host.close } # For some reason, I have to close the SSH connection # after spawning a process and running commands on a host, # or else it gets into a broken state for the next call. else result = block_hosts.map do |h| run_block_on h, &block end end elsif (cur_logger = (logger || @logger)) # there are no matching hosts to execute against # should warn here # check if logger is defined in this context cur_logger.info "Attempting to execute against an empty array of hosts (#{hosts}, filtered to #{block_hosts}), no execution will occur" end else result = yield block_hosts end result end
Execute a block selecting the hosts that match with the provided criteria
@param [Array<Host>, Host] hosts The host or hosts to run the provided block against @param [String, Symbol] filter Optional filter to apply to provided hosts - limits by name or role @param [Hash{Symbol=>String}] opts @option opts [Boolean] :run_in_parallel Whether to run on each host in parallel. @param [Block] block This method will yield to a block of code passed by the caller
@todo (beaker3.0:BKR-571): simplify return types to Array<Result> only
@return [Array<Result>, Result
, nil] If an array of hosts has been
passed (after filtering), then either an array of results is returned (if the array is non-empty), or nil is returned (if the array is empty). Else, a result object is returned. If filtering makes it such that only one host is left, then it's passed as a host object (not in an array), and thus a result object is returned.