Move logic re. header to header class

sbws/core/generate.py

@@ -2,7 +2,6 @@ from sbws.globals import (fail_hard, is_initted)
 from sbws.lib.v3bwfile import V3BwHeader
 from sbws.lib.resultdump import ResultSuccess
 from sbws.lib.resultdump import load_recent_results_in_datadir
-from sbws.util.filelock import FileLock
 from sbws.util.timestamp import unixts_to_isodt_str, unixts_to_str
 from argparse import ArgumentDefaultsHelpFormatter
 from statistics import median
@@ -104,24 +103,6 @@ def log_stats(data_lines):
     log.info('Mean bandwidth per line: %f "KiB"', bw_per_line)
 
 
-def read_started_ts(conf):
-    """Read ISO formated timestamp which represents the date and time
-    when scanner started.
-
-    :param ConfigParser conf: configuration
-    :returns: str, ISO formated timestamp
-    """
-    filepath = conf['paths']['started_filepath']
-    try:
-        with FileLock(filepath):
-            with open(filepath, 'r') as fd:
-                generator_started = fd.read()
-    except FileNotFoundError as e:
-        log.warn('File %s not found.%s', filepath, e)
-        return ''
-    return generator_started
-
-
 def main(args, conf):
     if not is_initted(args.directory):
         fail_hard('Sbws isn\'t initialized.  Try sbws init')
@@ -144,21 +125,11 @@ def main(args, conf):
     data_lines = [result_data_to_v3bw_line(results, fp) for fp in results]
     data_lines = sorted(data_lines, key=lambda d: d.bw, reverse=True)
     data_lines = scale_lines(args, data_lines)
+    log_stats(data_lines)
 
     # process header lines
     # FIXME: what to move to V3BwHeader?
-    generator_started = read_started_ts(conf)
-    # here it is ensured that we have results
-    lastest_bandwidth_unixts = max([r.time for fp in results
-                                    for r in results[fp]])
-    timestamp = unixts_to_str(lastest_bandwidth_unixts)
-    earliest_bandwidth_unixts = min([r.time for fp in results
-                                     for r in results[fp]])
-    earliest_bandwidth = unixts_to_isodt_str(earliest_bandwidth_unixts)
-    header = V3BwHeader(timestamp=timestamp,
-                        earliest_bandwidth=earliest_bandwidth,
-                        generator_started=generator_started)
-    log_stats(data_lines)
+    header = V3BwHeader.from_results(conf, results)
 
     # FIXME: move this to V3BwFile class?
     output = conf['paths']['v3bw_fname']

sbws/lib/v3bwfile.py

@@ -3,8 +3,10 @@
 (v3bw) used by bandwidth authorities."""
 
 import logging
+
 from sbws import __version__
 from sbws.globals import SPEC_VERSION
+from sbws.util.filelock import FileLock
 from sbws.util.timestamp import now_isodt_str, unixts_to_isodt_str
 
 log = logging.getLogger(__name__)
@@ -20,9 +22,29 @@ UNORDERED_KEYVALUES = EXTRA_ARG_KEYVALUES + ['lastest_bandwidth']
 # List of all the KeyValues currently being used to generate the file
 ALL_KEYVALUES = ['version'] + UNORDERED_KEYVALUES
 TERMINATOR = '===='
+# Num header lines in v1.1.0 using all the KeyValues
+NUM_LINES_HEADER_V110 = len(ALL_KEYVALUES) + 2
 LINE_TERMINATOR = TERMINATOR + LINE_SEP
 
 
+def read_started_ts(conf):
+    """Read ISO formated timestamp which represents the date and time
+    when scanner started.
+
+    :param ConfigParser conf: configuration
+    :returns: str, ISO formated timestamp
+    """
+    filepath = conf['paths']['started_filepath']
+    try:
+        with FileLock(filepath):
+            with open(filepath, 'r') as fd:
+                generator_started = fd.read()
+    except FileNotFoundError as e:
+        log.warn('File %s not found.%s', filepath, e)
+        return ''
+    return generator_started
+
+
 class V3BwHeader(object):
     """
     Create a bandwidth measurements (V3bw) header
@@ -40,7 +62,10 @@ class V3BwHeader(object):
           when the generator started
     """
     def __init__(self, timestamp, **kwargs):
-        self.timestamp = str(timestamp)
+        assert isinstance(timestamp, str)
+        for v in kwargs.values():
+            assert isinstance(v, str)
+        self.timestamp = timestamp
         # KeyValues with default value when not given by kwargs
         self.version = kwargs.get('version', SPEC_VERSION)
         self.software = kwargs.get('software', 'sbws')
@@ -132,3 +157,32 @@ class V3BwHeader(object):
         """
         assert isinstance(text, str)
         return self.from_lines_v110(text.split(LINE_SEP))
+
+    @property
+    def num_lines(self):
+        return len(self.__str__().split(LINE_SEP))
+
+    @staticmethod
+    def generator_started_from_file(conf):
+        return read_started_ts(conf)
+
+    @staticmethod
+    def lastest_bandwidth_from_results(results):
+        return max([r.time for fp in results for r in results[fp]])
+
+    @staticmethod
+    def earliest_bandwidth_from_results(results):
+        return min([r.time for fp in results for r in results[fp]])
+
+    @classmethod
+    def from_results(cls, conf, results):
+        kwargs = dict()
+        lastest_bandwidth = cls.lastest_bandwidth_from_results(results)
+        earliest_bandwidth = cls.lastest_bandwidth_from_results(results)
+        generator_started = cls.generator_started_from_file(conf)
+        timestamp = str(lastest_bandwidth)
+        kwargs['lastest_bandwidth'] = unixts_to_isodt_str(lastest_bandwidth)
+        kwargs['earliest_bandwidth'] = unixts_to_isodt_str(earliest_bandwidth)
+        kwargs['generator_started'] = generator_started
+        h = cls(timestamp, **kwargs)
+        return h