Class: Ruote::Exp::FlowExpression
- Inherits:
-
Object
- Object
- Ruote::Exp::FlowExpression
- Defined in:
- lib/ruote/exp/ro_on_x.rb,
lib/ruote/exp/ro_timers.rb,
lib/ruote/exp/ro_filters.rb,
lib/ruote/exp/ro_persist.rb,
lib/ruote/exp/ro_variables.rb,
lib/ruote/exp/ro_attributes.rb,
lib/ruote/exp/flow_expression.rb
Overview
Ruote is a process definition interpreter. It doesn’t directly “read” process definitions, it relies on a parser/generator to produce “abstract syntax trees” that look like
[ expression_name, { ... attributes ... }, [ children_expressions ] ]
The nodes (and leaves) in the trees are expressions. This is the base class for all expressions.
The most visible expressions are “define”, “sequence” and “participant”. Think :
pdef = Ruote.process_definition do
sequence do
participant :ref => 'customer'
participant :ref => 'accounting'
participant :ref => 'logistics'
end
end
Each node is an expression…
the states of an expression
nil
the normal state
‘cancelling’
the expression and its children are getting cancelled
‘dying’
the expression and its children are getting killed
‘failed’
the expression has finishing
‘failing’
the expression just failed and it’s cancelling its children
‘timing_out’
the expression just timedout and it’s cancelling its children
‘paused’
the expression is paused, it will store downstream messages and play them only when a ‘resume’ message comes from upstream.
Direct Known Subclasses
AddBranchesExpression, ApplyExpression, AwaitExpression, CancelProcessExpression, CommandExpression, CommandedExpression, ConcurrenceExpression, CronExpression, DefineExpression, EchoExpression, EqualsExpression, ErrorExpression, FilterExpression, ForgetExpression, IfExpression, ListenExpression, LoseExpression, NoOpExpression, OnErrorExpression, OnceExpression, ParticipantExpression, ReadExpression, RedoExpression, RefExpression, RegisterpExpression, ReserveExpression, RestoreExpression, SaveExpression, SequenceExpression, StallExpression, SubprocessExpression, UndoExpression, WaitExpression
Defined Under Namespace
Classes: HandlerEntry
Constant Summary collapse
- COMMON_ATT_KEYS =
%w[ if unless forget lose flank timeout timers on_error on_cancel on_timeout ]
Instance Attribute Summary collapse
-
#context ⇒ Object
readonly
Returns the value of attribute context.
-
#error ⇒ Object
Mostly used when the expression is returned via Ruote::Engine#ps(wfid) or Ruote::Engine#processes().
-
#h ⇒ Object
Returns the value of attribute h.
Class Method Summary collapse
-
.do_action(context, msg) ⇒ Object
Called by the worker when it has something to do for a FlowExpression.
-
.dummy(h) ⇒ Object
Returns a dummy expression.
-
.fetch(context, fei) ⇒ Object
Fetches an expression from the storage and readies it for service.
-
.from_h(context, h) ⇒ Object
Instantiates expression back from hash.
-
.names(*exp_names) ⇒ Object
Keeping track of names and aliases for the expression.
Instance Method Summary collapse
-
#ancestor?(fei) ⇒ Boolean
Returns true if the given fei points to an expression in the parent chain of this expression.
-
#applied_workitem ⇒ Object
Returns a one-off Ruote::Workitem instance (the applied workitem).
-
#att(keys, values, opts = {}) ⇒ Object
Returns the value for attribute ‘key’, this value should be present in the array list ‘values’.
-
#att_text(workitem = h.applied_workitem) ⇒ Object
Equivalent to #attribute_text, but will return nil if there is no attribute whose values is nil.
-
#attribute(n, workitem = h.applied_workitem, options = {}) ⇒ Object
Looks up the value for attribute n.
-
#attribute_text(workitem = h.applied_workitem) ⇒ Object
Given something like.
-
#attributes ⇒ Object
Returns the attributes of this expression (like { ‘ref’ => ‘toto’ } or { ‘timeout’ => ‘2d’ }..
-
#await(att, msg) ⇒ Object
If the expression has an :await attribute, the expression gets into a special “awaiting” state until the condition in the value of :await gets triggered and the trigger calls resume on the expression.
-
#cancel(flavour) ⇒ Object
This default implementation cancels all the [registered] children of this expression.
-
#cancel_flanks(flavour) ⇒ Object
Emits a cancel message for each flanking expression (if any).
-
#cfei_at(i) ⇒ Object
Given an index, returns the child fei (among the currently registered children feis) whose fei.expid ends with this index (whose child_id is equal to that index).
-
#child_id ⇒ Object
Returns the child_id for this expression.
-
#child_ids ⇒ Object
Returns the list of child_ids (last part of the fei.expid) for the currently registered (active) children.
-
#compile_atts(opts = {}) ⇒ Object
Returns a Hash containing all attributes set for an expression with their values resolved.
-
#compile_variables ⇒ Object
Returns a fresh hash of all the variables visible from this expression.
-
#debug_id ⇒ Object
Outputs ids like “0_2!d218c1b”, no wfid, only <expid>!<subid>[0, 7].
-
#deflate(err) ⇒ Object
Given this expression and an error, deflates the error into a hash (serializable).
-
#do(action, msg) ⇒ Object
Wraps a call to “apply”, “reply”, etc…
-
#do_apply(msg) ⇒ Object
Called by the worker when it has just created this FlowExpression and wants to apply it.
-
#do_cancel(msg) ⇒ Object
The raw handling of messages passed to expressions (the fine handling is done in the #cancel method).
-
#do_fail(msg) ⇒ Object
Called when handling an on_error, will place itself in a ‘failing’ state and cancel the children (when the reply from the children comes back, the on_error will get triggered).
-
#do_pause(msg) ⇒ Object
Expression received a “pause” message.
-
#do_persist ⇒ Object
Make sure to persist (retry if necessary).
-
#do_reply(msg) ⇒ Object
(also: #do_receive)
Wraps #reply (does the administrative part of the reply work).
-
#do_reply_to_parent(workitem, delete = true) ⇒ Object
The essence of the reply_to_parent job…
-
#do_resume(msg) ⇒ Object
Will “unpause” the expression (if it was paused), and trigger any ‘paused_replies’ (replies that came while the expression was paused).
-
#do_unpersist ⇒ Object
Make sure to unpersist (retry if necessary).
-
#fei ⇒ Object
Returns the Ruote::FlowExpressionId for this expression.
-
#handle_on_error(msg, error) ⇒ Object
Looks up parent with on_error attribute and triggers it.
-
#has_attribute(*args) ⇒ Object
(also: #has_att)
Given a list of attribute names, returns the first attribute name for which there is a value.
-
#initial_persist ⇒ Object
Persists and fetches the _rev identifier from the storage.
-
#initialize(context, h) ⇒ FlowExpression
constructor
A new instance of FlowExpression.
-
#is_concurrent? ⇒ Boolean
Concurrent expressions (expressions that apply more than one child at a time) are supposed to return true here.
-
#iterative_var_lookup(k) ⇒ Object
TODO : rdoc rewrite needed.
-
#launch_sub(pos, subtree, opts = {}) ⇒ Object
Launches a subprocesses (usually called from the #apply of certain expression implementations..
- #lookup_val(att_options = {}) ⇒ Object
-
#lookup_val_prefix(prefix, att_options = {}) ⇒ Object
prefix = ‘on’ => will lookup on, on_val, on_value, on_v, on_var, on_variable, on_f, on_fld, on_field…
-
#lookup_variable(var, prefix = nil) ⇒ Object
(also: #v, #lv)
Looks up the value of a variable in expression tree (seen from a leaf, it looks more like a stack than a tree).
-
#name ⇒ Object
Returns the name of this expression, like ‘sequence’, ‘participant’, ‘cursor’, etc…
-
#parent ⇒ Object
Fetches the parent expression, or returns nil if there is no parent expression.
-
#parent_id ⇒ Object
Returns the Ruote::FlowExpressionIf of the parent expression, or nil if there is no parent expression.
-
#pause_on_apply(msg) ⇒ Object
Called by #do_apply when msg == ‘paused’.
- #persist_or_raise ⇒ Object (also: #persist)
-
#reply(workitem) ⇒ Object
A default implementation for all the expressions.
-
#reply_to_parent(workitem, delete = true) ⇒ Object
FlowExpression call this method when they’re done and they want their parent expression to take over (it will end up calling the #reply of the parent expression).
-
#root(stubborn = false) ⇒ Object
An expensive method, looks up all the expressions with the same wfid in the storage (for some storages this is not expensive at all), and determine the root of this expression.
-
#root_id(stubborn = false) ⇒ Object
Returns the fei of the root expression of this expression.
-
#set_variable(var, val, override = false) ⇒ Object
Sets a variable to a given value.
-
#to_h ⇒ Object
Turns this FlowExpression instance into a Hash (well, just hands back the base hash behind it).
-
#tree ⇒ Object
Returns the current version of the tree (returns the updated version if it got updated..
-
#tree_children ⇒ Object
Returns the “AST” view on the children of this expression…
- #try_persist ⇒ Object
- #try_unpersist ⇒ Object
- #unpersist_or_raise ⇒ Object (also: #unpersist)
-
#unset_variable(var, override = false) ⇒ Object
Unbinds a variables.
-
#update_tree(t = nil) ⇒ Object
Updates the tree of this expression.
-
#variables ⇒ Object
A shortcut to the variables held in the expression (nil if none held).
-
#wfid ⇒ Object
Returns the workflow instance id of the workflow this expression belongs to.
Methods included from WithMeta
Methods included from WithH
Constructor Details
#initialize(context, h) ⇒ FlowExpression
Returns a new instance of FlowExpression.
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# File 'lib/ruote/exp/flow_expression.rb', line 124 def initialize(context, h) @context = context @msg = nil # contains generally the msg the expression got instantiated for self.h = h h._id ||= Ruote.to_storage_id(h.fei) h['type'] ||= 'expressions' h.name ||= self.class.expression_names.first h.children ||= [] h.applied_workitem['fei'] = h.fei h.created_time ||= Ruote.now_to_utc_s h.on_cancel ||= attribute(:on_cancel) h.on_error ||= attribute(:on_error) h.on_timeout ||= attribute(:on_timeout) h.on_terminate ||= attribute(:on_terminate) end |
Instance Attribute Details
#context ⇒ Object (readonly)
Returns the value of attribute context.
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# File 'lib/ruote/exp/flow_expression.rb', line 114 def context @context end |
#error ⇒ Object
Mostly used when the expression is returned via Ruote::Engine#ps(wfid) or Ruote::Engine#processes(). If an error occurred for this flow expression, #ps will set this error field so that it yields the ProcessError.
So, for short, usually, this attribute yields nil.
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# File 'lib/ruote/exp/flow_expression.rb', line 122 def error @error end |
#h ⇒ Object
Returns the value of attribute h.
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# File 'lib/ruote/exp/flow_expression.rb', line 99 def h @h end |
Class Method Details
.do_action(context, msg) ⇒ Object
Called by the worker when it has something to do for a FlowExpression.
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# File 'lib/ruote/exp/flow_expression.rb', line 320 def self.do_action(context, msg) fei = msg['fei'] action = msg['action'] if action == 'reply' && fei['engine_id'] != context.engine_id # # the reply has to go to another engine, let's locate the # 'engine participant' and give it the workitem/reply # # see ft_37 for a test/example engine_participant = context.plist.lookup(fei['engine_id'], msg['workitem']) raise( "no EngineParticipant found under name '#{fei['engine_id']}'" ) unless engine_participant engine_participant.reply(fei, msg['workitem']) return end # normal case fexp = nil n = context.storage.class.name.match(/Couch/) ? 3 : 1 # n.times do |i| if fexp = fetch(context, msg['fei']); break; end sleep 0.028 unless i == (n - 1) end # # Simplify that once ruote-couch behaves fexp.do(action, msg) if fexp end |
.dummy(h) ⇒ Object
Returns a dummy expression. Only used by the error_handler service.
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# File 'lib/ruote/exp/ro_on_x.rb', line 53 def self.dummy(h) class << h; include Ruote::HashDot; end fe = self.allocate fe.instance_variable_set(:@h, h) fe end |
.fetch(context, fei) ⇒ Object
Fetches an expression from the storage and readies it for service.
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# File 'lib/ruote/exp/flow_expression.rb', line 293 def self.fetch(context, fei) return nil if fei.nil? fexp = context.storage.get('expressions', Ruote.to_storage_id(fei)) fexp ? from_h(context, fexp) : nil end |
.from_h(context, h) ⇒ Object
Instantiates expression back from hash.
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# File 'lib/ruote/exp/flow_expression.rb', line 282 def self.from_h(context, h) return self.new(nil, h) unless context exp_class = context.expmap.expression_class(h['name']) exp_class.new(context, h) end |
.names(*exp_names) ⇒ Object
Keeping track of names and aliases for the expression
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# File 'lib/ruote/exp/flow_expression.rb', line 308 def self.names(*exp_names) exp_names = exp_names.collect { |n| n.to_s } (:expression_names) { exp_names } end |
Instance Method Details
#ancestor?(fei) ⇒ Boolean
Returns true if the given fei points to an expression in the parent chain of this expression.
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# File 'lib/ruote/exp/flow_expression.rb', line 881 def ancestor?(fei) fei = fei.to_h if fei.respond_to?(:to_h) return false unless h.parent_id return true if h.parent_id == fei parent.ancestor?(fei) end |
#applied_workitem ⇒ Object
Returns a one-off Ruote::Workitem instance (the applied workitem).
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# File 'lib/ruote/exp/flow_expression.rb', line 256 def applied_workitem @awi ||= Ruote::Workitem.new(h.applied_workitem) end |
#att(keys, values, opts = {}) ⇒ Object
Returns the value for attribute ‘key’, this value should be present in the array list ‘values’. If not, the default value is returned. By default, the default value is the first element of ‘values’.
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# File 'lib/ruote/exp/ro_attributes.rb', line 75 def att(keys, values, opts={}) default = opts[:default] || values.first val = Array(keys).collect { |key| attribute(key) }.compact.first.to_s values.include?(val) ? val : default end |
#att_text(workitem = h.applied_workitem) ⇒ Object
Equivalent to #attribute_text, but will return nil if there is no attribute whose values is nil.
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# File 'lib/ruote/exp/ro_attributes.rb', line 139 def att_text(workitem=h.applied_workitem) text = attributes.keys.find { |k| attributes[k] == nil } text ? dsub(text.to_s, workitem) : nil end |
#attribute(n, workitem = h.applied_workitem, options = {}) ⇒ Object
Looks up the value for attribute n.
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# File 'lib/ruote/exp/ro_attributes.rb', line 48 def attribute(n, workitem=h.applied_workitem, ={}) n = n.to_s default = [:default] escape = [:escape] string = [:to_s] || [:string] v = attributes[n] v = if v == nil default elsif escape v else dsub(v, workitem) end v = v.to_s if v and string v end |
#attribute_text(workitem = h.applied_workitem) ⇒ Object
Given something like
sequence do
participant 'alpha'
end
in the context of the participant expression
attribute_text()
will yield ‘alpha’.
Note : an empty text returns ”, not the nil value.
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# File 'lib/ruote/exp/ro_attributes.rb', line 129 def attribute_text(workitem=h.applied_workitem) text = attributes.keys.find { |k| attributes[k] == nil } dsub(text.to_s, workitem) end |
#attributes ⇒ Object
Returns the attributes of this expression (like { ‘ref’ => ‘toto’ } or { ‘timeout’ => ‘2d’ }.
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# File 'lib/ruote/exp/flow_expression.rb', line 935 def attributes tree[1] end |
#await(att, msg) ⇒ Object
If the expression has an :await attribute, the expression gets into a special “awaiting” state until the condition in the value of :await gets triggered and the trigger calls resume on the expression.
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# File 'lib/ruote/exp/flow_expression.rb', line 452 def await(att, msg) action, condition = Ruote::Exp::AwaitExpression.extract_await_ac(:await => att) raise ::ArgumentError.new( ":await does not understand #{att.inspect}" ) if action == nil msg.merge!('flavour' => 'awaiting') h.state = 'awaiting' h.paused_apply = msg persist_or_raise @context.tracker.add_tracker( h.fei['wfid'], action, Ruote.to_storage_id(h.fei), condition, { '_auto_remove' => true, 'action' => 'resume', 'fei' => h.fei, 'flavour' => 'awaiting' }) end |
#cancel(flavour) ⇒ Object
This default implementation cancels all the [registered] children of this expression.
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# File 'lib/ruote/exp/flow_expression.rb', line 742 def cancel(flavour) return reply_to_parent(h.applied_workitem) if h.children.empty? # # there are no children, nothing to cancel, let's just reply to # the parent expression do_persist || return # # before firing the cancel message to the children # # if the do_persist returns false, it means it failed, implying this # expression is stale, let's return, thus discarding this cancel message children.each do |child_fei| # # let's send a cancel message to each of the children # # maybe some of them are gone or have not yet been applied, anyway, # the messages are sent @context.storage.put_msg( 'cancel', 'fei' => child_fei, 'parent_id' => h.fei, # indicating that this is a "cancel child" 'flavour' => flavour) end end |
#cancel_flanks(flavour) ⇒ Object
Emits a cancel message for each flanking expression (if any).
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# File 'lib/ruote/exp/flow_expression.rb', line 724 def cancel_flanks(flavour) return unless h.flanks h.flanks.each do |flank_fei| @context.storage.put_msg( 'cancel', 'fei' => flank_fei, 'parent_id' => h.fei, # indicating that this is a "cancel child", well... 'flavour' => flavour) end end |
#cfei_at(i) ⇒ Object
Given an index, returns the child fei (among the currently registered children feis) whose fei.expid ends with this index (whose child_id is equal to that index).
Returns nil if not found or a child fei as a Hash.
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# File 'lib/ruote/exp/flow_expression.rb', line 267 def cfei_at(i) children.find { |cfei| Ruote.extract_child_id(cfei) == i } end |
#child_id ⇒ Object
Returns the child_id for this expression. (The rightmost part of the fei.expid).
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# File 'lib/ruote/exp/flow_expression.rb', line 180 def child_id fei.child_id end |
#child_ids ⇒ Object
Returns the list of child_ids (last part of the fei.expid) for the currently registered (active) children.
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# File 'lib/ruote/exp/flow_expression.rb', line 275 def child_ids children.collect { |cfei| Ruote.extract_child_id(cfei) } end |
#compile_atts(opts = {}) ⇒ Object
Returns a Hash containing all attributes set for an expression with their values resolved.
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# File 'lib/ruote/exp/ro_attributes.rb', line 108 def compile_atts(opts={}) attributes.keys.each_with_object({}) { |k, r| r[dsub(k)] = attribute(k, h.applied_workitem, opts) } end |
#compile_variables ⇒ Object
Returns a fresh hash of all the variables visible from this expression.
This is used mainly when forgetting an expression.
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# File 'lib/ruote/exp/ro_variables.rb', line 44 def compile_variables vars = h.parent_id ? parent.compile_variables : {} vars.merge!(h.variables) if h.variables vars end |
#debug_id ⇒ Object
Outputs ids like “0_2!d218c1b”, no wfid, only <expid>!<subid>[0, 7]
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# File 'lib/ruote/exp/ro_persist.rb', line 39 def debug_id "#{h.fei['expid']}!#{h.fei['subid'][0, 7]}" end |
#deflate(err) ⇒ Object
Given this expression and an error, deflates the error into a hash (serializable).
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# File 'lib/ruote/exp/ro_on_x.rb', line 37 def deflate(err) { 'fei' => h.fei, 'at' => Ruote.now_to_utc_s, 'class' => err.class.to_s, 'message' => err., 'trace' => err.backtrace, 'details' => err.respond_to?(:ruote_details) ? err.ruote_details : nil, 'deviations' => err.respond_to?(:deviations) ? err.deviations : nil, 'tree' => tree } end |
#do(action, msg) ⇒ Object
Wraps a call to “apply”, “reply”, etc… Makes sure to set @msg with a deep copy of the msg before.
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# File 'lib/ruote/exp/flow_expression.rb', line 362 def do(action, msg) @msg = Ruote.fulldup(msg) send("do_#{action}", msg) end |
#do_apply(msg) ⇒ Object
Called by the worker when it has just created this FlowExpression and wants to apply it.
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# File 'lib/ruote/exp/flow_expression.rb', line 372 def do_apply(msg) if msg['state'] == 'paused' return pause_on_apply(msg) end if msg['flavour'].nil? && (aw = attribute(:await)) return await(aw, msg) end unless Condition.apply?(attribute(:if), attribute(:unless)) return do_reply_to_parent(h.applied_workitem) end pi = h.parent_id reply_immediately = false if attribute(:scope).to_s == 'true' h.variables ||= {} end if attribute(:forget).to_s == 'true' h.variables = compile_variables h.parent_id = nil h.forgotten = true reply_immediately = true elsif attribute(:lose).to_s == 'true' h.lost = true elsif msg['flanking'] or (attribute(:flank).to_s == 'true') h.flanking = true reply_immediately = true end if reply_immediately and pi @context.storage.put_msg( 'reply', 'fei' => pi, 'workitem' => Ruote.fulldup(h.applied_workitem), 'flanking' => h.flanking) end filter consider_tag consider_timers apply end |
#do_cancel(msg) ⇒ Object
The raw handling of messages passed to expressions (the fine handling is done in the #cancel method).
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# File 'lib/ruote/exp/flow_expression.rb', line 682 def do_cancel(msg) flavour = msg['flavour'] return if h.state == 'cancelling' && flavour != 'kill' # cancel on cancel gets discarded return if h.state == 'failed' && flavour == 'timeout' # do not timeout expressions that are "in error" (failed) h.state = case flavour when 'kill' then 'dying' when 'timeout' then 'timing_out' else 'cancelling' end if h.state == 'timing_out' h.applied_workitem['fields']['__timed_out__'] = [ h.fei, Ruote.now_to_utc_s, tree.first, compile_atts ] elsif h.state == 'cancelling' if t = msg['on_cancel'] h.on_cancel = t elsif ra_opts = msg['re_apply'] ra_opts = {} if ra_opts == true ra_opts['tree'] ||= tree h.on_re_apply = ra_opts end end cancel(flavour) end |
#do_fail(msg) ⇒ Object
Called when handling an on_error, will place itself in a ‘failing’ state and cancel the children (when the reply from the children comes back, the on_error will get triggered).
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# File 'lib/ruote/exp/flow_expression.rb', line 775 def do_fail(msg) @h['state'] = 'failing' @h['applied_workitem'] = msg['workitem'] if h.children.size < 1 reply_to_parent(@h['applied_workitem']) else flavour = msg['immediate'] ? 'kill' : nil persist_or_raise h.children.each do |i| @context.storage.put_msg('cancel', 'fei' => i, 'flavour' => flavour) end end end |
#do_pause(msg) ⇒ Object
Expression received a “pause” message. Will put the expression in the “paused” state and then pass the message to the children.
If the expression is in a non-nil state (failed, timed_out, …), the message will be ignored.
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# File 'lib/ruote/exp/flow_expression.rb', line 802 def do_pause(msg) return if h.state != nil h['state'] = 'paused' do_persist || return h.children.each { |i| @context.storage.put_msg('pause', 'fei' => i) } unless msg['breakpoint'] end |
#do_persist ⇒ Object
Make sure to persist (retry if necessary).
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# File 'lib/ruote/exp/ro_persist.rb', line 106 def do_persist do_p(true) end |
#do_reply(msg) ⇒ Object Also known as: do_receive
Wraps #reply (does the administrative part of the reply work).
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# File 'lib/ruote/exp/flow_expression.rb', line 622 def do_reply(msg) workitem = msg['workitem'] fei = workitem['fei'] removed = h.children.delete(fei) # accept without any check ? if msg['flanking'] (h.flanks ||= []) << fei if (not removed) # then it's a timer do_persist return end end if ut = msg['updated_tree'] ct = tree.dup ct.last[Ruote::FlowExpressionId.child_id(fei)] = ut update_tree(ct) end if h.state == 'paused' (h['paused_replies'] ||= []) << msg do_persist elsif h.state != nil # failing or timing out ... if h.children.size < 1 reply_to_parent(workitem) else persist_or_raise # for the updated h.children end else # vanilla reply reply(workitem) end end |
#do_reply_to_parent(workitem, delete = true) ⇒ Object
The essence of the reply_to_parent job…
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# File 'lib/ruote/exp/flow_expression.rb', line 493 def do_reply_to_parent(workitem, delete=true) # propagate the cancel "flavour" back, so that one can know # why a branch got cancelled. flavour = if @msg.nil? nil elsif @msg['action'] == 'cancel' @msg['flavour'] || 'cancel' elsif h.state.nil? nil else @msg['flavour'] end # deal with the timers and the schedules %w[ timeout_schedule_id job_id ].each do |sid| @context.storage.delete_schedule(h[sid]) if h[sid] end # # legacy schedule ids, to be removed for ruote 2.4.0 @context.storage.delete_schedule(h.schedule_id) if h.schedule_id # # time-driven exps like cron, wait and once now all use h.schedule_id h.timers.each do |schedule_id, action| @context.storage.delete_schedule(schedule_id) end if h.timers # cancel flanking expressions if any cancel_flanks(h.state == 'dying' ? 'kill' : nil) # trigger or vanilla reply if h.state == 'failing' # on_error is implicit (#do_fail got called) trigger('on_error', workitem) elsif h.state == 'cancelling' && h.on_cancel trigger('on_cancel', workitem) elsif h.state == 'cancelling' && h.on_re_apply trigger('on_re_apply', workitem) elsif h.state == 'timing_out' && h.on_timeout trigger('on_timeout', workitem) elsif h.state == nil && h.on_reply trigger('on_reply', workitem) elsif h.flanking && h.state.nil? # # do vanish do_unpersist elsif h.lost && h.state.nil? # # do not reply, sit here (and wait for cancellation probably) do_persist elsif h.trigger && workitem['fields']["__#{h.trigger}__"] # # the "second take" trigger(h.trigger, workitem) else # vanilla reply filter(workitem) if h.state.nil? f = h.state.nil? && attribute(:vars_to_f) Ruote.set(workitem['fields'], f, h.variables) if f workitem['sub_wf_name'] = @h.applied_workitem['sub_wf_name'] workitem['sub_wf_revision'] = @h.applied_workitem['sub_wf_revision'] leave_tag(workitem) if h.tagname (do_unpersist || return) if delete # remove expression from storage if h.parent_id && ! h.attached @context.storage.put_msg( 'reply', 'fei' => h.parent_id, 'workitem' => workitem.merge!('fei' => h.fei), 'updated_tree' => h.updated_tree, # nil most of the time 'flavour' => flavour) else @context.storage.put_msg( (h.forgotten || h.attached) ? 'ceased' : 'terminated', 'wfid' => h.fei['wfid'], 'fei' => h.fei, 'workitem' => workitem, 'variables' => h.variables, 'flavour' => flavour) if h.state.nil? && h.on_terminate == 'regenerate' && ! (h.forgotten || h.attached) then @context.storage.put_msg( 'regenerate', 'wfid' => h.fei['wfid'], 'tree' => h.original_tree, 'workitem' => workitem, 'variables' => h.variables, 'flavour' => flavour) #'stash' => end end end end |
#do_resume(msg) ⇒ Object
Will “unpause” the expression (if it was paused), and trigger any ‘paused_replies’ (replies that came while the expression was paused).
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# File 'lib/ruote/exp/flow_expression.rb', line 818 def do_resume(msg) return unless h.state == 'paused' || h.state == 'awaiting' h['state'] = nil m = h.delete('paused_apply') return do_apply(m) if m # if it's a paused apply, pipe it directly to #do_apply replies = h.delete('paused_replies') || [] do_persist || return h.children.each { |i| @context.storage.put_msg('resume', 'fei' => i) } # resume children replies.each { |m| @context.storage.put_msg(m.delete('action'), m) } # trigger replies end |
#do_unpersist ⇒ Object
Make sure to unpersist (retry if necessary).
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# File 'lib/ruote/exp/ro_persist.rb', line 113 def do_unpersist do_p(false) end |
#fei ⇒ Object
Returns the Ruote::FlowExpressionId for this expression.
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# File 'lib/ruote/exp/flow_expression.rb', line 154 def fei Ruote::FlowExpressionId.new(h.fei) end |
#handle_on_error(msg, error) ⇒ Object
Looks up parent with on_error attribute and triggers it
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# File 'lib/ruote/exp/ro_on_x.rb', line 65 def handle_on_error(msg, error) return false if h.state == 'failing' err = deflate(error) oe_parent = lookup_on_error(err) return false unless oe_parent # no parent with on_error attribute found handler = oe_parent.local_on_error(err) return false if handler.to_s == '' # empty on_error handler nullifies ancestor's on_error workitem = msg['workitem'] workitem['fields']['__error__'] = err immediate = if handler.is_a?(String) !! handler.match(/^!/) elsif handler.is_a?(Array) !! handler.first.to_s.match(/^!/) else false end # NOTE: why not pass the handler in the msg? # no, because of HandlerEntry (not JSON serializable) @context.storage.put_msg( 'fail', 'fei' => oe_parent.h.fei, 'workitem' => workitem, 'immediate' => immediate) true # yes, error is being handled. end |
#has_attribute(*args) ⇒ Object Also known as: has_att
Given a list of attribute names, returns the first attribute name for which there is a value.
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# File 'lib/ruote/exp/ro_attributes.rb', line 37 def has_attribute(*args) args.each { |a| a = a.to_s; return a if attributes[a] != nil } nil end |
#initial_persist ⇒ Object
Persists and fetches the _rev identifier from the storage.
Only used by the worker when creating the expression.
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# File 'lib/ruote/exp/ro_persist.rb', line 48 def initial_persist r = @context.storage.put(@h, :update_rev => true) #t = Thread.current.object_id.to_s[-3..-1] #puts "+ per #{debug_id} #{tree[0]} r#{h._rev} t#{t} -> #{r.class}" #Ruote.p_caller('+ per') raise_or_return('initial_persist failed', r) end |
#is_concurrent? ⇒ Boolean
Concurrent expressions (expressions that apply more than one child at a time) are supposed to return true here.
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# File 'lib/ruote/exp/flow_expression.rb', line 241 def is_concurrent? false end |
#iterative_var_lookup(k) ⇒ Object
TODO : rdoc rewrite needed
This method is mostly used by the worker when looking up a process name or participant name bound under a variable.
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# File 'lib/ruote/exp/ro_variables.rb', line 114 def iterative_var_lookup(k) v = lookup_variable(k) return [ k, v ] unless (v.is_a?(String) or v.is_a?(Symbol)) iterative_var_lookup(v) end |
#launch_sub(pos, subtree, opts = {}) ⇒ Object
Launches a subprocesses (usually called from the #apply of certain expression implementations.
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# File 'lib/ruote/exp/flow_expression.rb', line 846 def launch_sub(pos, subtree, opts={}) i = h.fei.merge( 'subid' => Ruote.generate_subid(h.fei.inspect), 'expid' => pos) if ci = opts[:child_id] i['subid'] = "#{i['subid']}k#{ci}" end #p '=== launch_sub ===' #p [ :launcher, h.fei['expid'], h.fei['subid'], h.fei['wfid'] ] #p [ :launched, i['expid'], i['subid'], i['wfid'] ] forget = opts[:forget] register_child(i) unless forget variables = ( forget ? compile_variables : {} ).merge!(opts[:variables] || {}) @context.storage.put_msg( 'launch', 'fei' => i, 'parent_id' => forget ? nil : h.fei, 'tree' => subtree, 'workitem' => opts[:workitem] || h.applied_workitem, 'variables' => variables, 'forgotten' => forget) end |
#lookup_val(att_options = {}) ⇒ Object
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# File 'lib/ruote/exp/ro_attributes.rb', line 96 def lookup_val(={}) lval( VV, s_cartesian(%w[ v var variable ], VV), s_cartesian(%w[ f fld field ], VV), ) end |
#lookup_val_prefix(prefix, att_options = {}) ⇒ Object
prefix = ‘on’ => will lookup on, on_val, on_value, on_v, on_var, on_variable, on_f, on_fld, on_field…
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# File 'lib/ruote/exp/ro_attributes.rb', line 87 def lookup_val_prefix(prefix, ={}) lval( [ prefix ] + [ 'val', 'value' ].map { |s| "#{prefix}_#{s}" }, %w[ v var variable ].map { |s| "#{prefix}_#{s}" }, %w[ f fld field ].map { |s| "#{prefix}_#{s}" }, ) end |
#lookup_variable(var, prefix = nil) ⇒ Object Also known as: v, lv
Looks up the value of a variable in expression tree (seen from a leaf, it looks more like a stack than a tree)
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# File 'lib/ruote/exp/ro_variables.rb', line 55 def lookup_variable(var, prefix=nil) var, prefix = split_prefix(var, prefix) if prefix == '//' return @context.storage.get_engine_variable(var) end if prefix == '/' && par = parent return par.lookup_variable(var, prefix) end if h.variables and Ruote.has_key?(h.variables, var) return Ruote.lookup(h.variables, var) end if h.parent_id && h.parent_id['engine_id'] == @context.engine_id # # do not lookup variables in a remote engine ... (return parent.lookup_variable(var, prefix)) rescue nil # if the lookup fails (parent gone) then rescue and let go end @context.storage.get_engine_variable(var) end |
#name ⇒ Object
Returns the name of this expression, like ‘sequence’, ‘participant’, ‘cursor’, etc…
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# File 'lib/ruote/exp/flow_expression.rb', line 927 def name tree[0] end |
#parent ⇒ Object
Fetches the parent expression, or returns nil if there is no parent expression.
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# File 'lib/ruote/exp/flow_expression.rb', line 188 def parent h.parent_id ? Ruote::Exp::FlowExpression.fetch(@context, h.parent_id) : nil end |
#parent_id ⇒ Object
Returns the Ruote::FlowExpressionIf of the parent expression, or nil if there is no parent expression.
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# File 'lib/ruote/exp/flow_expression.rb', line 170 def parent_id h.parent_id ? Ruote::FlowExpressionId.new(h.parent_id) : nil end |
#pause_on_apply(msg) ⇒ Object
Called by #do_apply when msg == ‘paused’. Covers the “apply/launch it but it’s immediately paused” case. Freezes the apply message in h.paused_apply and saves the expression.
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# File 'lib/ruote/exp/flow_expression.rb', line 437 def pause_on_apply(msg) msg['state'] = nil h.state = 'paused' h.paused_apply = msg persist_or_raise end |
#persist_or_raise ⇒ Object Also known as: persist
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# File 'lib/ruote/exp/ro_persist.rb', line 91 def persist_or_raise p_or_raise(true) end |
#reply(workitem) ⇒ Object
A default implementation for all the expressions.
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# File 'lib/ruote/exp/flow_expression.rb', line 674 def reply(workitem) reply_to_parent(workitem) end |
#reply_to_parent(workitem, delete = true) ⇒ Object
FlowExpression call this method when they’re done and they want their parent expression to take over (it will end up calling the #reply of the parent expression).
Expression implementations are free to override this method. The common behaviour is in #do_reply_to_parent.
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# File 'lib/ruote/exp/flow_expression.rb', line 486 def reply_to_parent(workitem, delete=true) do_reply_to_parent(workitem, delete) end |
#root(stubborn = false) ⇒ Object
An expensive method, looks up all the expressions with the same wfid in the storage (for some storages this is not expensive at all), and determine the root of this expression. It does this by recursively going from an expression to its parent, starting with this expression. The root is when the parent can’t be reached.
By default, this method will always return an expression, but if stubborn is set to true and the top expression points to a gone parent then nil will be returned. The default (stubborn=true) is probably what you want anyway.
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# File 'lib/ruote/exp/flow_expression.rb', line 207 def root(stubborn=false) previous = nil current = @h exps = @context.storage.find_expressions( @h['fei']['wfid'] ).each_with_object({}) { |exp, h| h[exp['fei']] = exp } while current && current['parent_id'] previous = current current = exps[current['parent_id']] end current ||= previous unless stubborn current ? Ruote::Exp::FlowExpression.from_h(@context, current) : nil end |
#root_id(stubborn = false) ⇒ Object
Returns the fei of the root expression of this expression. The result is an instance of Ruote::FlowExpressionId.
Uses #root behind the scenes, hence the stubborn option.
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# File 'lib/ruote/exp/flow_expression.rb', line 233 def root_id(stubborn=false) root(stubborn).fei end |
#set_variable(var, val, override = false) ⇒ Object
Sets a variable to a given value. (will set at the appropriate level).
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# File 'lib/ruote/exp/ro_variables.rb', line 93 def set_variable(var, val, override=false) fexp, v = locate_set_var(var, override) || locate_var(var) fexp.un_set_variable(:set, v, val, (fexp.h.fei != h.fei)) if fexp end |
#to_h ⇒ Object
Turns this FlowExpression instance into a Hash (well, just hands back the base hash behind it).
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# File 'lib/ruote/exp/flow_expression.rb', line 249 def to_h @h end |
#tree ⇒ Object
Returns the current version of the tree (returns the updated version if it got updated.
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# File 'lib/ruote/exp/flow_expression.rb', line 898 def tree h.updated_tree || h.original_tree end |
#tree_children ⇒ Object
Returns the “AST” view on the children of this expression…
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# File 'lib/ruote/exp/flow_expression.rb', line 942 def tree_children tree[2] end |
#try_persist ⇒ Object
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# File 'lib/ruote/exp/ro_persist.rb', line 59 def try_persist r = @context.storage.put(@h) #t = Thread.current.object_id.to_s[-3..-1] #puts "+ per #{debug_id} #{tree[0]} r#{h._rev} t#{t} -> #{r.class}" #p self.h.children.collect { |i| Ruote.sid(i) } #Ruote.p_caller('+ per') r end |
#try_unpersist ⇒ Object
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# File 'lib/ruote/exp/ro_persist.rb', line 71 def try_unpersist r = @context.storage.delete(@h) #t = Thread.current.object_id.to_s[-3..-1] #puts "- unp #{debug_id} #{tree[0]} r#{h._rev} t#{t} -> #{r.class}" #Ruote.p_caller('- unp') return r if r #if h.has_error err = @context.storage.get('errors', "err_#{Ruote.to_storage_id(h.fei)}") @context.storage.delete(err) if err #end # removes any error in the journal for this expression # since it will now be gone, no need to keep track of its errors nil end |
#unpersist_or_raise ⇒ Object Also known as: unpersist
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# File 'lib/ruote/exp/ro_persist.rb', line 96 def unpersist_or_raise p_or_raise(false) end |
#unset_variable(var, override = false) ⇒ Object
Unbinds a variables.
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# File 'lib/ruote/exp/ro_variables.rb', line 102 def unset_variable(var, override=false) fexp, v = locate_set_var(var, override) || locate_var(var) fexp.un_set_variable(:unset, v, nil, (fexp.h.fei != h.fei)) if fexp end |
#update_tree(t = nil) ⇒ Object
Updates the tree of this expression
update_tree(t)
will set the updated tree to t
update_tree
will copy (deep copy) the original tree as the updated_tree.
Adding a child to a sequence expression :
seq.update_tree
seq.updated_tree[2] << [ 'participant', { 'ref' => 'bob' }, [] ]
seq.do_persist
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# File 'lib/ruote/exp/flow_expression.rb', line 919 def update_tree(t=nil) h.updated_tree = t || Ruote.fulldup(h.original_tree) end |
#variables ⇒ Object
A shortcut to the variables held in the expression (nil if none held).
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# File 'lib/ruote/exp/ro_variables.rb', line 35 def variables @h['variables'] end |
#wfid ⇒ Object
Returns the workflow instance id of the workflow this expression belongs to.
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# File 'lib/ruote/exp/flow_expression.rb', line 162 def wfid h.fei['wfid'] end |