Paths in parallel VTK files are now relative to that file (#141)

* Use relative paths in paralel VTK files

* Modify test

src/gridtypes/pvtk_grid.jl

@@ -109,18 +109,18 @@ function pvtk_grid(
     nparts = _pvtk_nparts(is_structured; kwargs...)
     extents = _pvtk_extents(is_structured; kwargs...)
 
-    mkpath(filename)
-    bname = basename(filename)
-    prefix = joinpath(filename, bname)
-    fn = _serial_filename(part, nparts, prefix, "")
+    dir_serial = filename * "_dir"  # directory where serial files will be written
+    mkpath(dir_serial)
+    prefix = _pvtk_vtk_filename_prefix(filename; relative_to_pvtk = false, create_dirs = true)
+    filename_serial = _serial_filename(part, nparts, prefix, "")
 
     vtk = let kws_vtk = _remove_parallel_kwargs(; kwargs...)
         kws = if extents === nothing
             kws_vtk
         else
             (; kws_vtk..., extent = extents[part])
         end
-        vtk_grid(fn, args...; kws...)
+        vtk_grid(filename_serial, args...; kws...)
     end
 
     pvtkargs = PVTKArgs(part, nparts, ismain, ghost_level)
@@ -200,6 +200,26 @@ function _serial_filename(part, nparts, prefix, extension)
     prefix * "_$p" * extension
 end
 
+# Determine base filename (or "prefix") for serial VTK files included in a parallel VTK
+# file.
+# Here `path` is the basename of the main pvtk file (without the extension).
+# Note that it can be in a subdirectory of `.`, and it can either be an absolute or relative
+# path.
+# If it is an absolute value, then always return an absolute value.
+function _pvtk_vtk_filename_prefix(path; relative_to_pvtk, create_dirs = false)
+    dir_serial = path  # directory where serial files will be written
+    if create_dirs
+        mkpath(dir_serial)
+    end
+    bname = basename(path)
+    if isabspath(path) || !relative_to_pvtk
+        joinpath(dir_serial, bname)
+    else
+        _, reldir = splitdir(dir_serial)
+        joinpath(reldir, bname)
+    end
+end
+
 function _init_pvtk!(pvtk::PVTKFile, extents)
     # Recover some data
     vtk = pvtk.vtk
@@ -208,7 +228,7 @@ function _init_pvtk!(pvtk::PVTKFile, extents)
     npieces = pvtkargs.nparts
     pref, _ = splitext(pvtk.path)
     _, ext = splitext(vtk.path)
-    prefix = joinpath(pref, basename(pref))
+    prefix = _pvtk_vtk_filename_prefix(pref; relative_to_pvtk = true)
 
     # VTKFile (root) node
     pvtk_root = create_root(pvtk.xdoc, "VTKFile")

test/checksums.sha1

@@ -73,10 +73,10 @@ e7ff55d7c8bb2c1739a2dc73c0c1fdeff2f7d536  prectilinear/prectilinear_1.vtr
 b8b456b99f45f45e2e0fcc0de56963185b3f24ec  prectilinear/prectilinear_4.vtr
 a6fd8a0367efc31e7616dd7046f048c424aa8ae0  prectilinear/prectilinear_5.vtr
 b1ef0b3a9e3c25781c31e0d2ceb552c78dab23f8  prectilinear/prectilinear_6.vtr
-d9c0b2367bf7ba42534a134b3ef4dace753560a9  pstructured.pvts
-92ff18a7c1c631800de3adc3b0bd4631e16be845  pstructured/pstructured_1.vts
-9bb94bd6b2374156e60df995340e3b395f2ae6b9  pstructured/pstructured_2.vts
-ad4b841fdf277c6138bbd763f4db2a359c46e400  pstructured/pstructured_3.vts
-651905ba5698b503f58d40fc1051267fefa4b49e  pstructured/pstructured_4.vts
-bba1504744a03b3f9594fcfe63435b7311e030fe  pstructured/pstructured_5.vts
-2e8acea4c25a7ef64c25c05ff3f65b3890a52e72  pstructured/pstructured_6.vts
+d9c0b2367bf7ba42534a134b3ef4dace753560a9  pvtk_structured_output/pstructured.pvts
+92ff18a7c1c631800de3adc3b0bd4631e16be845  pvtk_structured_output/pstructured/pstructured_1.vts
+9bb94bd6b2374156e60df995340e3b395f2ae6b9  pvtk_structured_output/pstructured/pstructured_2.vts
+ad4b841fdf277c6138bbd763f4db2a359c46e400  pvtk_structured_output/pstructured/pstructured_3.vts
+651905ba5698b503f58d40fc1051267fefa4b49e  pvtk_structured_output/pstructured/pstructured_4.vts
+bba1504744a03b3f9594fcfe63435b7311e030fe  pvtk_structured_output/pstructured/pstructured_5.vts
+2e8acea4c25a7ef64c25c05ff3f65b3890a52e72  pvtk_structured_output/pstructured/pstructured_6.vts

test/pvtk_grid.jl

@@ -104,10 +104,14 @@ function pvtk_rectilinear()
     collect(Iterators.flatten(filenames))
 end
 
+# In this test we write to a subdirectory using relative paths.
 function pvtk_structured()
     Ns, extents = make_structured_partition()
     nparts = length(extents)  # number of "processes"
     filenames = Vector{Vector{String}}(undef, nparts)
+    outdir = "pvtk_structured_output"
+    mkpath(outdir)
+    outname = joinpath(outdir, "pstructured")
     @sync for (n, extent) ∈ enumerate(extents)
         @spawn begin
             points = [
@@ -121,7 +125,7 @@ function pvtk_structured()
             point_data = map(sum, points)
             processid = fill(n, length.(extent) .- 1)  # cell data
             filenames[n] = pvtk_grid(
-                "pstructured", points;
+                outname, points;
                 part = n, extents = extents,
                 append = false, compress = false,
             ) do vtk