fix OpenStack indexing

src/openstack.jl

@@ -31,13 +31,19 @@ DD.data_eltype(::OpenStack{<:Any,<:Any,T}) where T = T
 
 Base.keys(::OpenStack{<:Any,K}) where K = K
 # TODO test this, and does it make sense to return an iterator here?
-Base.values(os::OpenStack{<:Any,K}) where K = (os[k] for k in K)
+Base.values(os::OpenStack{<:Any,K}) where K = map(k -> os[k], K)
+Base.NamedTuple(os::OpenStack{<:Any,K}) where K = NamedTuple{K}(values(os))
+Base.map(f, os::OpenStack) = map(f, NamedTuple(os))
 # Indexing OpenStack returns memory-backed Raster. 
+Base.iterate(os::OpenStack) = iterate(os, 1)
+Base.iterate(os::OpenStack, i::Integer) = i > length(os) ? nothing : (os[i], i + 1)
+Base.length(os::OpenStack{<:Any,K}) where K = length(K)
 function Base.getindex(os::OpenStack{<:Any,K}, key::Symbol) where K
     mods = os.mods
-    if mods isa AbstractModifications
-        _maybe_modify(dataset(os)[key], mods)
+    var = _open(os, key)
+    return if mods isa AbstractModifications
+        _maybe_modify(var, mods)
     else
-        _maybe_modify(dataset(os)[key], NamedTuple{K}(mods)[key])
+        _maybe_modify(var, NamedTuple{K}(mods)[key])
     end
 end

src/sources/commondatamodel.jl

@@ -83,12 +83,16 @@ function _open(f, source::CDMsource, ds::AbstractDataset;
         cleanreturn(f(g)) 
     else
         key = string(_name_or_firstname(g, name))
-        v = CDM.variable(g, key)
+        v = _open(g, key)
         _open(f, source, v; mod)
     end
 end
 _open(f, ::CDMsource, var::AbstractArray; mod=NoMod(), kw...) = 
     cleanreturn(f(_maybe_modify(var, mod)))
+_open(os::OpenStack{<:CDMsource}, key::Union{AbstractString,Symbol}) = _open(dataset(os), key)
+# Both needed for ambiguity
+_open(os::AbstractDataset, key::AbstractString) = CDM.variable(os, key)
+_open(os::AbstractDataset, key::Symbol) = CDM.variable(os, key)
 
 # This allows arbitrary group nesting
 _getgroup(ds, ::Union{Nothing,NoKW}) = ds
@@ -129,7 +133,7 @@ end
 function _layers(ds::AbstractDataset, ::NoKW=nokw, ::NoKW=nokw)
     nondim = _nondimnames(ds)
     grid_mapping = String[]
-    vars = map(k -> CDM.variable(ds, k), nondim)
+    vars = map(k -> _open(ds, k), nondim)
     attrs = map(CDM.attribs, vars)
     for attr in attrs
         if haskey(attr, "grid_mapping")
@@ -146,7 +150,7 @@ end
 _layers(ds::AbstractDataset, names, ::NoKW) = 
     _layers(ds, collect(names), nokw)
 function _layers(ds::AbstractDataset, names::Vector, ::NoKW)
-    vars = map(n -> CDM.variable(ds, n), names)
+    vars = map(n -> _open(ds, n), names)
     attrs = map(CDM.attribs, vars)
     (; names, vars, attrs)
 end

src/stack.jl

@@ -542,11 +542,7 @@ end
 # Open a single file stack
 function Base.open(f::Function, st::AbstractRasterStack{K}; kw...) where K
     ost = OpenStack(parent(st))
-    # TODO is this needed?
-    layers = map(K) do k
-        ost[k]
-    end |> NamedTuple{K}
-    out = f(rebuild(st; data=layers))
+    out = f(rebuild(st; data=ost))
     close(ost)
     return out
 end

test/sources/ncdatasets.jl

@@ -1,4 +1,4 @@
-using Rasters, DimensionalData, Test, Statistics, Dates, CFTime, Plots, CommonDataModel
+using Rasters, DimensionalData, Test, Statistics, Dates, CFTime, Plots, CommonDataModel, DiskArrays
 
 using Rasters.Lookups, Rasters.Dimensions
 using Rasters.DiskArrays
@@ -626,4 +626,21 @@ if !haskey(ENV, "CI") && isfile(h5path)
     end
 end
 
+@testset "OpenStack indexing" begin
+    DiskArrays.allowscalar(true)
+    filename = tempname() * ".nc"
+    rs = Rasters.create(
+        filename, (;a = Float64), (X(1:10),);
+        fill=NaN, 
+        missingval=NaN
+    )
+    rs_lazy = RasterStack(filename; lazy=true, raw=true)
+    ras_lazy = Raster(filename; lazy=true, raw=true)
+
+    @test isequal(open(first, rs), open(first, rs_lazy))
+    @test isequal(open(first, rs_lazy), (; a=NaN))
+    @test isnan(open(first, ras_lazy))
+    DiskArrays.allowscalar(false)
+end
+
 nothing