Add Silent and implement setting optimizer attributes in caching and mock optimizers

docs/src/apireference.md

@@ -84,10 +84,11 @@ AbstractOptimizer
 optimize!
 ```
 
-List of attributes optimizers attributes
+List of optimizers attributes
 
 ```@docs
 SolverName
+Silent
 ```
 
 List of attributes useful for optimizers

src/Utilities/cachingoptimizer.jl

@@ -80,6 +80,11 @@ function reset_optimizer(m::CachingOptimizer, optimizer::MOI.AbstractOptimizer)
     @assert MOI.is_empty(optimizer)
     m.optimizer = optimizer
     m.state = EMPTY_OPTIMIZER
+    for attr in MOI.get(m.model_cache, MOI.ListOfOptimizerAttributesSet())
+        value = MOI.get(m.model_cache, attr)
+        optimizer_value = attribute_value_map(m.model_to_optimizer_map, value)
+        MOI.set(m.optimizer, attr, optimizer_value)
+    end
     return
 end
 
@@ -501,16 +506,24 @@ function MOI.get(m::CachingOptimizer, IdxT::Type{<:MOI.Index}, name::String)
     return MOI.get(m.model_cache, IdxT, name)
 end
 
-# TODO: MOI.set for MOI.AbstractOptimizerAttribute.
+function MOI.set(model::CachingOptimizer, attr::MOI.AbstractOptimizerAttribute,
+                 value)
+    optimizer_value = attribute_value_map(model.model_to_optimizer_map, value)
+    if model.optimizer !== nothing
+        MOI.set(model.optimizer, attr, optimizer_value)
+    end
+    MOI.set(model.model_cache, attr, value)
+end
 
 function MOI.get(model::CachingOptimizer, attr::MOI.AbstractOptimizerAttribute)
     if state(model) == NO_OPTIMIZER
+        # TODO: Copyable attributes (e.g., `Silent`, `TimeLimit`) should also be
+        # stored in the cache so we could return the value stored in the cache
+        # instead. However, for non-copyable attributes( e.g. `SolverName`) the
+        # error is appropriate.
         error("Cannot query $(attr) from caching optimizer because no " *
               "optimizer is attached.")
     end
-    # TODO: Copyable attributes (e.g., TimeLimit) could also be stored in the
-    # cache. When MOI.set is implemented for MOI.AbstractOptimizerAttribute,
-    # make sure this case is handled correctly.
     return attribute_value_map(model.optimizer_to_model_map,
                                MOI.get(model.optimizer, attr))
 end

src/Utilities/mockoptimizer.jl

@@ -151,7 +151,9 @@ MOI.set(mock::MockOptimizer, ::MockModelAttribute, value::Integer) = (mock.attri
 function MOI.supports(mock::MockOptimizer, attr::MOI.AbstractModelAttribute)
     return MOI.supports(mock.inner_model, attr)
 end
-function MOI.set(mock::MockOptimizer, attr::MOI.AbstractModelAttribute, value)
+function MOI.set(mock::MockOptimizer,
+                 attr::Union{MOI.AbstractModelAttribute,
+                             MOI.AbstractOptimizerAttribute}, value)
     MOI.set(mock.inner_model, attr, value)
 end
 MOI.set(mock::MockOptimizer, attr::MOI.ObjectiveFunction, value) = MOI.set(mock.inner_model, attr, xor_variables(value))
@@ -164,7 +166,11 @@ MOI.set(mock::MockOptimizer, ::MockConstraintAttribute, idx::MOI.ConstraintIndex
 MOI.set(mock::MockOptimizer, ::MOI.ConstraintDual, idx::MOI.ConstraintIndex, value) = (mock.condual[xor_index(idx)] = value)
 MOI.set(mock::MockOptimizer, ::MOI.ConstraintBasisStatus, idx::MOI.ConstraintIndex, value) = (mock.con_basis[xor_index(idx)] = value)
 
-MOI.get(mock::MockOptimizer, attr::MOI.AbstractModelAttribute) = MOI.get(mock.inner_model, attr)
+function MOI.get(mock::MockOptimizer,
+                 attr::Union{MOI.AbstractModelAttribute,
+                             MOI.AbstractOptimizerAttribute})
+    return MOI.get(mock.inner_model, attr)
+end
 MOI.get(mock::MockOptimizer, attr::Union{MOI.ListOfVariableIndices,
                                          MOI.ListOfConstraintIndices}) = xor_index.(MOI.get(mock.inner_model, attr))
 MOI.get(mock::MockOptimizer, attr::MOI.ObjectiveFunction) = xor_variables(MOI.get(mock.inner_model, attr))

src/attributes.jl

@@ -337,6 +337,27 @@ An optimizer attribute for the string identifying the solver/optimizer.
 """
 struct SolverName <: AbstractOptimizerAttribute end
 
+"""
+    Silent
+
+An optimizer attribute for silencing the output of an optimizer. When `set`
+to `true`, it takes precedence over any other attribute controlling verbosity
+and requires the solver to produce no output. The default value is `false`
+which has no effect. In this case the verbosity is controlled by other
+attributes.
+
+## Note
+
+Every optimizer should have verbosity on by default. For instance, if a solver
+has a solver-specific log level attribute, the MOI implementation should set it
+to `1` by default. If the user sets `Silent` to `true`, then the log level
+should be set to `0`, even if the user specifically sets a value of log level.
+If the value of `Silent` is `false` then the log level set to the solver is the
+value given by the user for this solver-specific parameter or `1` if none is
+given.
+"""
+struct Silent <: AbstractOptimizerAttribute end
+
 ## Model attributes
 
 """

test/Utilities/cachingoptimizer.jl

@@ -30,16 +30,45 @@
         exception = ErrorException(
             "Cannot query $(attr) from caching optimizer because no optimizer" *
             " is attached.")
-        @test_throws Exception MOI.get(model, MOI.SolverName())
+        @test_throws exception MOI.get(model, attr)
+        attr = MOI.Silent()
+        exception = ErrorException(
+            "Cannot query $(attr) from caching optimizer because no optimizer" *
+            " is attached.")
+        @test_throws exception MOI.get(model, attr)
 
         attr = MOI.ResultCount()
         exception = ErrorException(
             "Cannot query $(attr) from caching optimizer because no optimizer" *
             " is attached.")
-        @test_throws Exception MOI.get(model, MOI.ResultCount())
+        @test_throws exception MOI.get(model, attr)
     end
 end
 
+@testset "Copyable solver attributes" begin
+    cache = MOIU.UniversalFallback(ModelForCachingOptimizer{Float64}())
+    cached = MOIU.CachingOptimizer(cache, MOIU.MANUAL)
+    MOI.set(cached, MOI.Silent(), true)
+    mock = MOIU.MockOptimizer(MOIU.UniversalFallback(ModelForMock{Float64}()))
+    MOIU.reset_optimizer(cached, mock)
+    @test MOI.get(mock, MOI.Silent())
+    @test MOI.get(cached, MOI.Silent())
+    MOI.set(cached, MOI.Silent(), false)
+    @test !MOI.get(mock, MOI.Silent())
+    @test !MOI.get(cached, MOI.Silent())
+    mock = MOIU.MockOptimizer(MOIU.UniversalFallback(ModelForMock{Float64}()))
+    MOIU.reset_optimizer(cached, mock)
+    @test !MOI.get(mock, MOI.Silent())
+    @test !MOI.get(cached, MOI.Silent())
+    MOI.set(cached, MOI.Silent(), true)
+    @test MOI.get(mock, MOI.Silent())
+    @test MOI.get(cached, MOI.Silent())
+    mock = MOIU.MockOptimizer(MOIU.UniversalFallback(ModelForMock{Float64}()))
+    MOIU.reset_optimizer(cached, mock)
+    @test MOI.get(mock, MOI.Silent())
+    @test MOI.get(cached, MOI.Silent())
+end
+
 @testset "CachingOptimizer MANUAL mode" begin
     m = MOIU.CachingOptimizer(ModelForCachingOptimizer{Float64}(), MOIU.MANUAL)
     @test MOIU.state(m) == MOIU.NO_OPTIMIZER