Remove MPS from HDF5 file

src/MIPLearn.jl

@@ -66,6 +66,7 @@ export DynamicLazyConstraintsComponent,
     ObjectiveValueComponent,
     PrimalSolutionComponent,
     StaticLazyConstraintsComponent,
-    MinPrecisionThreshold
+    MinPrecisionThreshold,
+    Hdf5Sample
 
 end # module

src/instance/file_instance.jl

@@ -2,6 +2,7 @@
 #  Copyright (C) 2020-2021, UChicago Argonne, LLC. All rights reserved.
 #  Released under the modified BSD license. See COPYING.md for more details.
 
+using JLD2
 import Base: flush
 
 mutable struct FileInstance <: Instance
@@ -9,13 +10,13 @@ mutable struct FileInstance <: Instance
     loaded::Union{Nothing,JuMPInstance}
     filename::AbstractString
     h5::PyCall.PyObject
-    lazycb::Union{Nothing,Tuple{Function,Function}}
+    build_model::Function
 
     function FileInstance(
-        filename::AbstractString;
-        lazycb::Union{Nothing,Tuple{Function,Function}} = nothing,
+        filename::AbstractString,
+        build_model::Function,
     )::FileInstance
-        instance = new(nothing, nothing, filename, nothing, lazycb)
+        instance = new(nothing, nothing, filename, nothing, build_model)
         instance.py = PyFileInstance(instance)
         instance.h5 = Hdf5Sample(filename)
         instance.filename = filename
@@ -55,7 +56,8 @@ end
 
 function load(instance::FileInstance)
     if instance.loaded === nothing
-        instance.loaded = load_instance(instance.filename, lazycb = instance.lazycb)
+        data = load_data(instance.filename)
+        instance.loaded = JuMPInstance(instance.build_model(data))
     end
 end
 
@@ -65,6 +67,16 @@ function free(instance::FileInstance)
     GC.gc()
 end
 
+function save_data(filename::AbstractString, data)::Nothing
+    jldsave(filename, data = data)
+end
+
+function load_data(filename::AbstractString)
+    jldopen(filename, "r") do file
+        return file["data"]
+    end
+end
+
 function flush(instance::FileInstance) end
 
 function __init_PyFileInstance__()

src/instance/jump_instance.jl

@@ -121,49 +121,4 @@ function __init_PyJuMPInstance__()
     copy!(PyJuMPInstance, Class)
 end
 
-function save(filename::AbstractString, instance::JuMPInstance)::Nothing
-    # Convert JuMP model to MPS
-    mps_filename = "$(tempname()).mps.gz"
-    model = instance.py.to_model()
-    write_to_file(model, mps_filename)
-    mps = read(mps_filename)
-
-    # Generate HDF5
-    h5 = Hdf5Sample(filename, mode = "w")
-    h5.put_scalar("miplearn_version", "0002")
-    h5.put_bytes("mps", mps)
-
-    ext = copy(model.ext[:miplearn])
-    delete!(ext, "lazy_find_cb")
-    delete!(ext, "lazy_enforce_cb")
-    h5.put_scalar("jump_ext", JSON.json(ext))
-    return
-end
-
-function _check_miplearn_version(h5)
-    v = h5.get_scalar("miplearn_version")
-    v == "0002" || error(
-        "The file you are trying to load has been generated by " *
-        "MIPLearn $(v) and you are currently running MIPLearn 0002 " *
-        "Reading files generated by different versions of MIPLearn is " *
-        "not currently supported.",
-    )
-end
-
-function load_instance(
-    filename::AbstractString;
-    lazycb::Union{Nothing,Tuple{Function,Function}} = nothing,
-)::JuMPInstance
-    h5 = Hdf5Sample(filename)
-    _check_miplearn_version(h5)
-    mps = h5.get_bytes("mps")
-    ext = JSON.parse(h5.get_scalar("jump_ext"))
-    if lazycb !== nothing
-        ext["lazy_find_cb"] = lazycb[1]
-        ext["lazy_enforce_cb"] = lazycb[2]
-    end
-    instance = JuMPInstance(Vector{UInt8}(mps), ext)
-    return instance
-end
-
 export JuMPInstance, save, load_instance