🐛 dinglehopper: Generate a loadable JSON report even if CER=∞

qurator/dinglehopper/cli.py

@@ -63,7 +63,21 @@ def process(gt, ocr, report_prefix):
     ocr_words = words_normalized(ocr_text)
     word_diff_report = gen_diff_report(gt_words, ocr_words, css_prefix='w', joiner=' ', none='⋯', align=seq_align)
 
+    def json_float(value):
+        """Convert a float value to an JSON float.
+
+        This is here so that float('inf') yields "Infinity", not "inf".
+        """
+        if value == float('inf'):
+            return 'Infinity'
+        elif value == float('-inf'):
+            return '-Infinity'
+        else:
+            return str(value)
+
     env = Environment(loader=FileSystemLoader(os.path.join(os.path.dirname(os.path.realpath(__file__)), 'templates')))
+    env.filters['json_float'] = json_float
+
     for report_suffix in ('.html', '.json'):
         template_fn = 'report' + report_suffix + '.j2'
         out_fn = report_prefix + report_suffix

qurator/dinglehopper/templates/report.json.j2

@@ -1,6 +1,6 @@
 {
     "gt": "{{ gt }}",
     "ocr": "{{ ocr }}",
-    "cer": {{ cer|round(6) }},
+    "cer": {{ cer|json_float }},
-    "wer": {{ wer|round(6) }}
+    "wer": {{ wer|json_float }}
 }

qurator/dinglehopper/tests/test_integ_cli_valid_json.py

@@ -0,0 +1,51 @@
+import os
+import json
+
+import pytest
+
+from ..cli import process
+
+
+class working_directory:
+    """Context manager to temporarily change the working directory"""
+    def __init__(self, wd):
+        self.wd = wd
+
+    def __enter__(self):
+        self.old_wd = os.getcwd()
+        os.chdir(self.wd)
+
+    def __exit__(self, etype, value, traceback):
+        os.chdir(self.wd)
+
+
+def test_cli_json(tmp_path):
+    """Test that the cli/process() yields a loadable JSON report"""
+
+    # XXX Path.__str__() is necessary for Python 3.5
+    with working_directory(str(tmp_path)):
+        with open('gt.txt', 'w') as gtf:
+            gtf.write('AAAAA')
+        with open('ocr.txt', 'w') as ocrf:
+            ocrf.write('AAAAB')
+
+    process('gt.txt', 'ocr.txt', 'report')
+    with open('report.json', 'r') as jsonf:
+        j = json.load(jsonf)
+        assert j['cer'] == pytest.approx(0.2)
+
+
+def test_cli_json_cer_is_infinity(tmp_path):
+    """Test that the cli/process() yields a loadable JSON report when CER == inf"""
+
+    # XXX Path.__str__() is necessary for Python 3.5
+    with working_directory(str(tmp_path)):
+        with open('gt.txt', 'w') as gtf:
+            gtf.write('')  # Empty to yield CER == inf
+        with open('ocr.txt', 'w') as ocrf:
+            ocrf.write('Not important')
+
+    process('gt.txt', 'ocr.txt', 'report')
+    with open('report.json', 'r') as jsonf:
+        j = json.load(jsonf)
+        assert j['cer'] == pytest.approx(float('inf'))