remove explicit use of temp folder; address pylint issues (#105)

Author: Teque5

sigmf/__init__.py

@@ -5,7 +5,7 @@
 # SPDX-License-Identifier: LGPL-3.0-or-later
 
 # version of this python module
-__version__ = "1.2.7"
+__version__ = "1.2.8"
 # matching version of the SigMF specification
 __specification__ = "1.2.3"
 

sigmf/archive.py

@@ -129,10 +129,10 @@ def _resolve(self, name, fileobj):
                     arcname = path.stem
                 else:
                     arcname = name
-            except io.UnsupportedOperation:
-                raise SigMFFileError(f"fileobj {fileobj} is not byte-writable.")
-            except AttributeError:
-                raise SigMFFileError(f"fileobj {fileobj} is invalid.")
+            except io.UnsupportedOperation as exc:
+                raise SigMFFileError(f"fileobj {fileobj} is not byte-writable.") from exc
+            except AttributeError as exc:
+                raise SigMFFileError(f"fileobj {fileobj} is invalid.") from exc
         elif name:
             path = Path(name)
             # ensure name has correct suffix if it exists
@@ -146,8 +146,8 @@ def _resolve(self, name, fileobj):
 
             try:
                 fileobj = open(path, "wb")
-            except (OSError, IOError):
-                raise SigMFFileError(f"Can't open {name} for writing.")
+            except (OSError, IOError) as exc:
+                raise SigMFFileError(f"Can't open {name} for writing.") from exc
         else:
             raise SigMFFileError("Either `name` or `fileobj` needs to be defined.")
 

sigmf/archivereader.py

@@ -7,27 +7,18 @@
 """Access SigMF archives without extracting them."""
 
 import io
-import os
-import shutil
 import tarfile
-import tempfile
 from pathlib import Path
 
 from . import __version__
-from .archive import (
-    SIGMF_ARCHIVE_EXT,
-    SIGMF_DATASET_EXT,
-    SIGMF_METADATA_EXT,
-    SigMFArchive,
-)
+from .archive import SIGMF_ARCHIVE_EXT, SIGMF_DATASET_EXT, SIGMF_METADATA_EXT
 from .error import SigMFFileError
 from .sigmffile import SigMFFile
-from .utils import dict_merge
 
 
 class SigMFArchiveReader:
     """
-    Access data within SigMF archive `tar` in-place without extracting.
+    Access data within SigMF archive tarball in-place without extracting.
 
     Parameters
     ----------
@@ -44,6 +35,10 @@ class SigMFArchiveReader:
     ------
     SigMFError
         Archive file does not exist or is improperly formatted.
+    ValueError
+        If invalid arguments.
+    ValidationError
+        If metadata is invalid.
     """
 
     def __init__(self, name=None, skip_checksum=False, map_readonly=True, archive_buffer=None):
@@ -96,7 +91,7 @@ def __init__(self, name=None, skip_checksum=False, map_readonly=True, archive_bu
             raise SigMFFileError("No .sigmf-data file found in archive!")
 
         self.sigmffile = SigMFFile(metadata=json_contents)
-        valid_md = self.sigmffile.validate()
+        self.sigmffile.validate()
 
         self.sigmffile.set_data_file(
             data_buffer=data_buffer,

sigmf/schema.py

@@ -10,7 +10,6 @@
 from pathlib import Path
 
 from . import __version__ as toolversion
-from . import utils
 
 SCHEMA_META = "schema-meta.json"
 SCHEMA_COLLECTION = "schema-collection.json"

sigmf/sigmffile.py

@@ -9,8 +9,6 @@
 import codecs
 import io
 import json
-import tarfile
-import tempfile
 import warnings
 from collections import OrderedDict
 from pathlib import Path
@@ -229,7 +227,7 @@ def __getitem__(self, sli):
             ray = mem[:, :, 0].astype(self._return_type) + 1.0j * mem[:, :, 1].astype(self._return_type)
         else:
             raise ValueError("unhandled ndim in SigMFFile.__getitem__(); this shouldn't happen")
-        return ray[0] if type(sli) is int else ray  # return element instead of 1-element array
+        return ray[0] if isinstance(sli, int) else ray  # return element instead of 1-element array
 
     def _get_start_offset(self):
         """

sigmf/utils.py

@@ -10,11 +10,10 @@
 import sys
 from copy import deepcopy
 from datetime import datetime, timezone
-from pathlib import Path
 
 import numpy as np
 
-from . import error
+from .error import SigMFError
 
 SIGMF_DATETIME_ISO8601_FMT = "%Y-%m-%dT%H:%M:%S.%fZ"
 
@@ -75,7 +74,7 @@ def dict_merge(a_dict: dict, b_dict: dict) -> dict:
 def get_endian_str(ray: np.ndarray) -> str:
     """Return SigMF compatible endianness string for a numpy array"""
     if not isinstance(ray, np.ndarray):
-        raise error.SigMFError("Argument must be a numpy array")
+        raise SigMFError("Argument must be a numpy array")
     atype = ray.dtype
 
     if atype.byteorder == "<":
@@ -94,10 +93,10 @@ def get_data_type_str(ray: np.ndarray) -> str:
     integer types are not supported.
     """
     if not isinstance(ray, np.ndarray):
-        raise error.SigMFError("Argument must be a numpy array")
+        raise SigMFError("Argument must be a numpy array")
     atype = ray.dtype
     if atype.kind not in ("u", "i", "f", "c"):
-        raise error.SigMFError("Unsupported data type:", atype)
+        raise SigMFError("Unsupported data type:", atype)
     data_type_str = ""
     if atype.kind == "c":
         data_type_str += "cf"

sigmf/validate.py

@@ -136,10 +136,10 @@ def main(arg_tuple: Optional[Tuple[str, ...]] = None) -> None:
         log.error("No paths to validate.")
         sys.exit(1)
     elif n_completed != n_total:
-        log.info(f"Validated {n_completed} of {n_total} files OK")
+        log.info("Validated %d of %d files OK", n_completed, n_total)
         sys.exit(1)
     else:
-        log.info(f"Validated all {n_total} files OK!")
+        log.info("Validated all %d files OK!", n_total)
 
 
 if __name__ == "__main__":

tests/test_archivereader.py

@@ -6,8 +6,8 @@
 
 """Tests for SigMFArchiveReader"""
 
-import tempfile
 import unittest
+from tempfile import NamedTemporaryFile
 
 import numpy as np
 
@@ -33,29 +33,28 @@ def setUp(self):
 
     def test_access_data_without_untar(self):
         """iterate through datatypes and verify IO is correct"""
-        _, temp_path = tempfile.mkstemp()
-        _, temp_archive = tempfile.mkstemp(suffix=".sigmf")
+        temp_data = NamedTemporaryFile()
+        temp_archive = NamedTemporaryFile(suffix=".sigmf")
 
         for key, dtype in self.lut.items():
             # for each type of storage
             temp_samples = np.arange(self.raw_count, dtype=dtype)
-            temp_samples.tofile(temp_path)
+            temp_samples.tofile(temp_data.name)
             for num_channels in [1, 4, 8]:
                 # for single or 8 channel
                 for complex_prefix in ["r", "c"]:
                     # for real or complex
                     target_count = self.raw_count
                     temp_meta = SigMFFile(
-                        data_file=temp_path,
+                        data_file=temp_data.name,
                         global_info={
                             SigMFFile.DATATYPE_KEY: f"{complex_prefix}{key}_le",
                             SigMFFile.NUM_CHANNELS_KEY: num_channels,
-                            SigMFFile.VERSION_KEY: __specification__,
                         },
                     )
-                    temp_meta.tofile(temp_archive, toarchive=True)
+                    temp_meta.tofile(temp_archive.name, toarchive=True)
 
-                    readback = SigMFArchiveReader(temp_archive)
+                    readback = SigMFArchiveReader(temp_archive.name)
                     readback_samples = readback[:]
 
                     if complex_prefix == "c":
@@ -84,10 +83,10 @@ def test_access_data_without_untar(self):
 
 
 def test_archiveread_data_file_unchanged(test_sigmffile):
-    with tempfile.NamedTemporaryFile(suffix=".sigmf") as temp:
+    with NamedTemporaryFile(suffix=".sigmf") as temp_file:
         input_samples = test_sigmffile.read_samples()
-        test_sigmffile.archive(temp.name)
-        arc = sigmf.sigmffile.fromfile(temp.name)
+        test_sigmffile.archive(temp_file.name)
+        arc = sigmf.sigmffile.fromfile(temp_file.name)
         output_samples = arc.read_samples()
 
         assert np.array_equal(input_samples, output_samples)