RF: Convert pooch retrieval to interface, allow setting cache dir

nibabies/interfaces/download.py

@@ -0,0 +1,73 @@
+import json
+import os
+from pathlib import Path
+
+import pooch
+from nipype.interfaces.base import (
+    DynamicTraitedSpec,
+    File,
+    SimpleInterface,
+    TraitedSpec,
+    traits,
+)
+
+import nibabies
+
+
+class _RetrievePoochFilesInputSpec(DynamicTraitedSpec):
+    intermediate = traits.Str(required=True, desc='the intermediate space')
+    target = traits.Str(required=True, desc='the target space')
+
+
+class _RetrievePoochFilesOutputSpec(TraitedSpec):
+    int2tgt_xfm = File(desc='Intermediate to target transform')
+    tgt2int_xfm = File(desc='Target to intermediate transform')
+
+
+class RetrievePoochFiles(SimpleInterface):
+    input_spec = _RetrievePoochFilesInputSpec
+    output_spec = _RetrievePoochFilesOutputSpec
+
+    def _run_interface(self, runtime):
+        int2tgt, tgt2int = _retrieve_xfms(self.inputs.intermediate, self.inputs.target)
+        self._results['int2tgt_xfm'] = int2tgt
+        self._results['tgt2int_xfm'] = tgt2int
+        return runtime
+
+
+def _retrieve_xfms(
+    intermediate: str,
+    target: str,
+):
+    """Fetch transforms from the OSF repository (https://osf.io/y763j/)."""
+
+    manifest = json.loads(nibabies.data.load('xfm_manifest.json').read_text())
+
+    def sanitize(space):
+        # MNIInfant:cohort-1 -> MNIInfant+1
+        return space.replace(':cohort-', '+')
+
+    intmd = sanitize(intermediate)
+    tgt = sanitize(target)
+
+    cache_dir = Path(os.getenv('NIBABIES_POOCH_DIR', Path.cwd()))
+
+    int2std_name = f'from-{intmd}_to-{tgt}_xfm.h5'
+    int2std_meta = manifest[int2std_name]
+    int2std = pooch.retrieve(
+        url=int2std_meta['url'],
+        path=cache_dir,
+        known_hash=int2std_meta['hash'],
+        fname=int2std_name,
+    )
+
+    std2int_name = f'from-{tgt}_to-{intmd}_xfm.h5'
+    std2int_meta = manifest[std2int_name]
+    std2int = pooch.retrieve(
+        url=std2int_meta['url'],
+        path=cache_dir,
+        known_hash=std2int_meta['hash'],
+        fname=std2int_name,
+    )
+
+    return int2std, std2int

nibabies/interfaces/tests/test_download.py

@@ -0,0 +1,19 @@
+from pathlib import Path
+
+from nibabies.interfaces.download import RetrievePoochFiles
+
+
+def test_RetrievePoochFiles(tmp_path, monkeypatch):
+    monkeypatch.chdir(tmp_path)
+    getter = RetrievePoochFiles(intermediate='MNIInfant:cohort-1', target='MNI152NLin6Asym')
+    outputs = getter.run().outputs
+    assert Path(outputs.int2tgt_xfm).exists()
+    assert Path(outputs.tgt2int_xfm).exists()
+
+    cache = tmp_path / 'mycache'
+    monkeypatch.setenv('NIBABIES_POOCH_DIR', cache)
+    getter = RetrievePoochFiles(intermediate='MNIInfant:cohort-1', target='MNI152NLin6Asym')
+    outputs = getter.run().outputs
+
+    assert Path(outputs.int2tgt_xfm) == cache / 'from-MNIInfant+1_to-MNI152NLin6Asym_xfm.h5'
+    assert Path(outputs.tgt2int_xfm) == cache / 'from-MNI152NLin6Asym_to-MNIInfant+1_xfm.h5'

nibabies/workflows/anatomical/registration.py

@@ -345,6 +345,7 @@
         further use in downstream nodes.
 
     """
+    from nibabies.interfaces.download import RetrievePoochFiles
     from nibabies.interfaces.patches import CompositeTransformUtil
 
     ntpls = len(templates)
@@ -405,11 +406,9 @@
     outputnode = pe.Node(niu.IdentityInterface(fields=out_fields), name='outputnode')
 
     intermed_xfms = pe.MapNode(
-        niu.Function(
-            function=_load_intermediate_xfms, output_names=['int2std_xfm', 'std2int_xfm']
-        ),
-        name='intermed_xfms',
-        iterfield=['std'],
+        RetrievePoochFiles(),
+        name='retrieve_xfms',
+        iterfield=['target'],
         run_without_submitting=True,
     )
 
@@ -464,10 +463,10 @@
         # Transform concatenation
         (inputnode, dis_anat2int, [('anat2int_xfm', 'in_file')]),
         (inputnode, dis_int2anat, [('int2anat_xfm', 'in_file')]),
-        (inputnode, intermed_xfms, [('intermediate', 'intermediate')]),
-        (inputnode, intermed_xfms, [('template', 'std')]),
-        (intermed_xfms, dis_int2std, [('int2std_xfm', 'in_file')]),
-        (intermed_xfms, dis_std2int, [('std2int_xfm', 'in_file')]),
+        (inputnode, intermed_xfms, [('intermediate', 'intermediate'),
+                                    ('template', 'target')]),
+        (intermed_xfms, dis_int2std, [('int2tgt_xfm', 'in_file')]),
+        (intermed_xfms, dis_std2int, [('tgt2int_xfm', 'in_file')]),
         (dis_anat2int, order_anat2std, [
             ('affine_transform', 'in1'),
             ('displacement_field', 'in2'),
@@ -505,40 +504,6 @@
     return workflow
 
 
-def _load_intermediate_xfms(intermediate, std):
-    """Fetch transforms from the OSF repository (https://osf.io/y763j/)."""
-    import json
-    from pathlib import Path
-
-    import pooch
-
-    from nibabies.data import load
-
-    xfms = json.loads(load('xfm_manifest.json').read_text())
-    # MNIInfant:cohort-1 -> MNIInfant+1
-    intmed = intermediate.replace(':cohort-', '+')
-
-    int2std_name = f'from-{intmed}_to-{std}_xfm.h5'
-    int2std_meta = xfms[int2std_name]
-    int2std = pooch.retrieve(
-        url=int2std_meta['url'],
-        path=Path.cwd(),
-        known_hash=int2std_meta['hash'],
-        fname=int2std_name,
-    )
-
-    std2int_name = f'from-{std}_to-{intmed}_xfm.h5'
-    std2int_meta = xfms[std2int_name]
-    std2int = pooch.retrieve(
-        url=std2int_meta['url'],
-        path=Path.cwd(),
-        known_hash=std2int_meta['hash'],
-        fname=std2int_name,
-    )
-
-    return int2std, std2int
-
-
 def _create_inverse_composite(in_file, out_file='inverse_composite.h5'):
     """
     Build a composite transform with SimpleITK.