Class: Grimoire::Solver
- Includes:
- Bogo::Memoization
- Defined in:
- lib/grimoire/solver.rb
Overview
Requirement solver
Constant Summary collapse
- MAX_GENERATION_LOOPS =
Ceiling for number of loops allowed during path generation
100000
Instance Attribute Summary collapse
-
#new_world ⇒ System, NilClass
readonly
New system subset when pruning.
-
#world ⇒ System
readonly
Subset of full system based on requirements.
Instance Method Summary collapse
-
#apply_restrictions! ⇒ self
Restrictions are simply an implicit expansion of the requirements that.
-
#build_world(deps = nil, my_world = nil, root = nil) ⇒ Object
Build the world required for the solver (the subset of the entire system required by the requirements).
- #create_queue ⇒ Bogo::PriorityQueue
-
#generate! ⇒ Bogo::PriorityQueue<Path>
Generate valid constraint paths.
-
#initialize(*_) ⇒ Solver
constructor
A new instance of Solver.
-
#populate_queue(p_queue, units) ⇒ Bogo::PriorityQueue
Populate queue with units.
-
#prune_world! ⇒ self
After the world has been generated extraneous units will be included as a result of dependency constraints that may be too loose and are not actually required by any resolution that would be requested.
- #queues ⇒ Smash<{Unit#name:Bogo::PriorityQueue}>
-
#reset_queue(name) ⇒ self
Repopulate the given queue.
-
#resolve(dep, given = nil, current = []) ⇒ Array<Unit>
Resolve path for a given dependency.
-
#score_unit(unit, score) ⇒ Numeric
Provide score for given unit.
-
#unit_for(dep) ⇒ Unit
Provide Unit acceptable for given dependency.
Methods inherited from Utility
Constructor Details
#initialize(*_) ⇒ Solver
Returns a new instance of Solver.
28 29 30 31 32 33 34 35 36 37 38 39 |
# File 'lib/grimoire/solver.rb', line 28 def initialize(*_) super @world = System.new @new_world = nil @log = [] if(restrictions) apply_restrictions! end build_world(requirements.requirements, world, system) @log.clear world.scrub! end |
Instance Attribute Details
#new_world ⇒ System, NilClass (readonly)
Returns new system subset when pruning.
26 27 28 |
# File 'lib/grimoire/solver.rb', line 26 def new_world @new_world end |
#world ⇒ System (readonly)
Returns subset of full system based on requirements.
24 25 26 |
# File 'lib/grimoire/solver.rb', line 24 def world @world end |
Instance Method Details
#apply_restrictions! ⇒ self
Restrictions are simply an implicit expansion of the requirements that. When restrictions are provided, it serves to further restrict the valid units available for solutions
46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 |
# File 'lib/grimoire/solver.rb', line 46 def apply_restrictions! restrictions.requirements.each do |rst| req = requirements.requirements.detect do |r| r.name == rst.name end if(req) new_req = req.merge(rst) requirements.requirements.delete(req) requirements.requirements.push(new_req) else requirements.requirements.push(rst) end end self end |
#build_world(deps = nil, my_world = nil, root = nil) ⇒ Object
Build the world required for the solver (the subset of the entire system required by the requirements)
116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 |
# File 'lib/grimoire/solver.rb', line 116 def build_world(deps=nil, my_world=nil, root = nil) deps = requirement.requirements unless deps my_world = world unless my_world root = system unless root deps.each do |dep| units = root.subset(dep.name, dep.requirement) sha = Digest::SHA256.hexdigest(MultiJson.dump(units)) if(@log.include?(sha)) debug "Units checksum already added to world. Skipping. (`#{sha}`)" next end debug "Logging units checksum for world addition. (`#{sha}`)" @log.push(sha) units.each do |unit| build_world(unit.dependencies, my_world, root) end debug "Units added to world: #{MultiJson.dump(units.map{|u| {u.name => u.version} })}" my_world.add_unit(units) end end |
#create_queue ⇒ Bogo::PriorityQueue
138 139 140 141 142 143 144 |
# File 'lib/grimoire/solver.rb', line 138 def create_queue if(score_keeper) Bogo::PriorityQueue.new(score_keeper.preferred_score) else Bogo::PriorityQueue.new end end |
#generate! ⇒ Bogo::PriorityQueue<Path>
Generate valid constraint paths
270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 |
# File 'lib/grimoire/solver.rb', line 270 def generate! if(requirements.requirements.empty?) raise ArgumentError.new 'No cookbook constraints provided within Batali file!' end custom_unit = Unit.new( :name => '~_SOLVER_UNIT_~', :version => '1.0.0', :dependencies => requirements.requirements ) count = 0 debug "Solver Unit: #{MultiJson.dump(custom_unit)}" debug{ "Solver world context of unit system: #{world.inspect}" } results = Bogo::PriorityQueue.new begin until(count >= result_limit) result = resolve(nil, custom_unit) results.push(Path.new(:units => result.slice(1, result.size)), count) count += 1 end rescue Error::UnitUnavailable => e debug "Failed to locate unit: #{e}" count = nil end if(results.empty?) raise Error::NoSolution.new("Failed to generate valid path for requirements: `#{custom_unit.dependencies}`") else results end end |
#populate_queue(p_queue, units) ⇒ Bogo::PriorityQueue
Populate queue with units
164 165 166 167 168 169 170 171 |
# File 'lib/grimoire/solver.rb', line 164 def populate_queue(p_queue, units) i = 0 units = units.map do |unit| [unit, score_unit(unit, i += 1)] end p_queue.multi_push(units) p_queue end |
#prune_world! ⇒ self
This must be called explicitly and is provided for resolving an entire system, not a single resolution path
After the world has been generated extraneous units will be included as a result of dependency constraints that may be too loose and are not actually required by any resolution that would be requested. This will run a second pass and remove extraneous items not required.
71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 |
# File 'lib/grimoire/solver.rb', line 71 def prune_world! @new_world = System.new requirements.requirements.each do |req| unless(world.units[req.name]) debug "No units available matching requirement name `#{req.name}`! (#{req.inspect})" exception = Error::UnitUnavailable.new "No units available for requirement `#{req.name}`" exception.unit_name = req.name raise exception end world.units[req.name].delete_if do |r_unit| unless(req.requirement.satisfied_by?(r_unit.version)) debug "Pruning unit due to root requirement satisfaction failure - #{req.name}: #{req.requirement} not satisfied by #{r_unit.name} @ #{r_unit.version}" true end end end requirements.requirements.each do |req| world.units[req.name].each do |r_unit| begin req_list = RequirementList.new( :name => :world_pruner, :requirements => [[r_unit.name, r_unit.version.version]] ) path = Solver.new( :requirements => req_list, :system => world, :score_keeper => score_keeper ).generate!.pop new_world.add_unit(*path.units) rescue Error::NoSolution => e debug "Failed to generate valid path for: #{r_unit.name}-#{r_unit.version}" end end end @world = new_world @new_world = nil self end |
#queues ⇒ Smash<{Unit#name:Bogo::PriorityQueue}>
147 148 149 150 151 152 153 154 155 156 157 |
# File 'lib/grimoire/solver.rb', line 147 def queues memoize(:queues) do Smash[ world.units.map do |name, items| queue = create_queue populate_queue(queue, items) [name, queue] end ] end end |
#reset_queue(name) ⇒ self
Repopulate the given queue
190 191 192 193 194 195 196 197 |
# File 'lib/grimoire/solver.rb', line 190 def reset_queue(name) queue = populate_queue( create_queue, world.units.fetch(name, []) ) queues[name] = queue self end |
#resolve(dep, given = nil, current = []) ⇒ Array<Unit>
Resolve path for a given dependency
227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 |
# File 'lib/grimoire/solver.rb', line 227 def resolve(dep, given=nil, current=[]) unit = given || unit_for(dep) if(unit.dependencies.empty?) [unit] else deps = [unit] begin unit.dependencies.map do |u_dep| existing = (current + deps).detect{|d| d.name == u_dep.name} if(existing) if(u_dep.requirement.satisfied_by?(existing.version)) next else deps.delete(existing) reset_queue(u_dep.name) unless given end else reset_queue(u_dep.name) unless given end deps += resolve(u_dep, nil, current + deps) deps.compact! u_dep end.compact.map do |u_dep| # validator existing = deps.detect{|d| d.name == u_dep.name} if(existing) unless(u_dep.requirement.satisfied_by?(existing.version)) deps.delete(existing) reset_queue(u_dep.name) raise Error::ResolutionPathInvalid.new("Unit <#{existing.inspect}> does not satisfy <#{u_dep.inspect}>") end end end rescue Error::ResolutionPathInvalid => e debug "Resolution path deadend: #{e} (trying new path)" retry end deps.uniq end end |
#score_unit(unit, score) ⇒ Numeric
Provide score for given unit
178 179 180 181 182 183 184 |
# File 'lib/grimoire/solver.rb', line 178 def score_unit(unit, score) if(score_keeper) score_keeper.score_for(unit, score, :solver => self) || score else score end end |
#unit_for(dep) ⇒ Unit
Provide Unit acceptable for given dependency
204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 |
# File 'lib/grimoire/solver.rb', line 204 def unit_for(dep) unit = nil if(queues[dep.name].nil?) raise KeyError.new "No valid units for requested name found within system! (`#{dep.name}`)" end until(unit || queues[dep.name].empty?) unit = queues[dep.name].pop unit = nil unless dep.requirement.satisfied_by?(unit.version) end unless(unit) error = Error::UnitUnavailable.new("Failed to locate valid unit for: #{dep.inspect}") error.unit_name = dep.name raise error end unit end |