Add loading from Loaders

unitpackage/entry.py

@@ -144,7 +144,7 @@ def __dir__(self):
             >>> dir(entry) # doctest: +ELLIPSIS +NORMALIZE_WHITESPACE
             [... 'bibliography', 'citation', 'create_examples', 'curation',
             'dataDescription', 'df', 'experimental', 'field_unit', 'figureDescription',
-            'from_csv', 'from_df', 'from_local', 'identifier', 'mutable_resource',  'plot',
+            'from_csv', 'from_df', 'from_loader', 'from_local', 'identifier', 'mutable_resource', 'plot',
             'rename_fields', 'rescale', 'resource',  'save', 'source', 'system', 'yaml']
 
         """
@@ -847,6 +847,56 @@ def from_df(cls, df, metadata=None, fields=None, outdir=None, *, basename):
             os.path.join(outdir, csvname), metadata=metadata, fields=fields
         )
 
+    @classmethod
+    def from_loader(cls, filename=None, loaderName=None, metadata=None):
+        r"""
+        Returns an entry constructed from a loader known to unitpackage in loaders.
+
+        TODO: Shoule be accesible from the loader class.
+
+        available names:
+        * 'eclab'
+
+        EXAMPLES::
+
+            >>> from unitpackage.entry import Entry
+            >>> entry = Entry.from_loader(filename='test/loader_data/eclab_cv.mpt', loaderName='eclab')
+            >>> entry
+            Entry('eclab_cv')
+
+            >>> entry.df  # doctest: +NORMALIZE_WHITESPACE
+                mode  ox/red  error  ...      (Q-Qo)/C  I Range       P/W
+            0      2       1      0  ...  0.000000e+00       41  0.000001
+            1      2       0      0  ... -3.622761e-08       41 -0.000003
+            ...
+
+        """
+        from unitpackage.loaders.baseloader import BaseLoader
+
+        from pathlib import Path
+
+        path = Path(filename)
+
+        fields = None
+
+        if metadata:
+            import yaml
+            metadata = yaml.load(metadata, Loader=yaml.SafeLoader)
+            try:
+                fields = metadata["figure description"]["fields"]
+            except (KeyError, AttributeError):
+                logger.warning("No units to the fields provided in the metadata")
+
+        if not loaderName:
+            csv = BaseLoader(filename)
+        else:
+            csv = BaseLoader.create('eclab')(open(filename, 'r'))
+
+        entry = cls.from_df(df=csv.df, metadata=metadata, basename=path.stem, fields=fields)
+
+        return entry
+
+
     def save(self, *, outdir, basename=None):
         r"""
         Create a Data Package, i.e., a CSV file and a JSON file, in the directory ``outdir``.
@@ -930,7 +980,7 @@ def save(self, *, outdir, basename=None):
 
         resource = self.resource.to_dict()
 
-        # update the fields from the main resource with those from the "MutableResource"resource
+        # update the fields from the main resource with those from the "MutableResource" resource
         resource["schema"]["fields"] = self.mutable_resource.schema.fields
         resource["schema"] = resource["MutableResource"].schema.to_dict()
         del resource["MutableResource"]

unitpackage/loaders/baseloader.py

@@ -129,8 +129,30 @@ def file(self):
 
         return StringIO(self._file)
 
-    @staticmethod
-    def create(device=None):
+    @classmethod
+    def _loaders(cls):
+        r"""
+        A dictionary of known loaders.
+        """
+        return {"eclab": __import__('unitpackage.loaders.eclabloader').loaders.eclabloader.ECLabLoader,
+                "gamry": __import__('unitpackage.loaders.gamryloader').loaders.gamryloader.GamryLoader}
+
+    @classmethod
+    def known_loaders(cls):
+        r"""
+        A list of known loaders. Refer to the documentation for details
+        on supported file types for the individual Loaders.
+
+        EXAMPLES::
+
+            >>> BaseLoader.known_loaders()
+            ['eclab', 'gamry']
+
+        """
+        return list(cls._loaders().keys())
+
+    @classmethod
+    def create(cls, device=None):
         r"""
         Calls a specific `loader` based on a given device.
 
@@ -152,18 +174,19 @@ def create(device=None):
             0     2       0    0.1       0          0
             1     2       1    1.4       5          1
 
-        """
-        if device == "eclab":
-            from unitpackage.loaders.eclabloader import ECLabLoader
+        An unknown device loader provides a list with supported Loaders::
 
-            return ECLabLoader
+            >>> BaseLoader.create('unknown_device') # doctest: +NORMALIZE_WHITESPACE
+            Traceback (most recent call last):
+            ...
+            KeyError: "Device wth name 'unknown_device' is not in the list of supported Loaders (['eclab', 'gamry'])'."
 
-        if device == "gamry":
-            from unitpackage.loaders.gamryloader import GamryLoader
+        """
+        if device in BaseLoader.known_loaders():
 
-            return GamryLoader
+            return cls._loaders()[device]
 
-        raise KeyError(f"Device wth name '{device}' is unknown to the loader'.")
+        raise KeyError(f"Device wth name '{device}' is not in the list of supported Loaders ({cls.known_loaders()})'.")
 
     @property
     def header_lines(self):