1 files changed, 122 insertions, 0 deletions
diff --git a/glances/exports/glances_csv/__init__.py b/glances/exports/glances_csv/__init__.py
new file mode 100644
index 00000000..88e0615a
--- /dev/null
+++ b/glances/exports/glances_csv/__init__.py
@@ -0,0 +1,122 @@
+# -*- coding: utf-8 -*-
+#
+# This file is part of Glances.
+#
+# SPDX-FileCopyrightText: 2022 Nicolas Hennion <nicolas@nicolargo.com>
+#
+# SPDX-License-Identifier: LGPL-3.0-only
+#
+
+"""CSV interface class."""
+
+import os.path
+import csv
+import sys
+import time
+
+from glances.globals import iterkeys, itervalues
+from glances.logger import logger
+from glances.exports.export import GlancesExport
+
+
+class Export(GlancesExport):
+
+    """This class manages the CSV export module."""
+
+    def __init__(self, config=None, args=None):
+        """Init the CSV export IF."""
+        super(Export, self).__init__(config=config, args=args)
+
+        # CSV file name
+        self.csv_filename = args.export_csv_file
+
+        # Set the CSV output file
+        # (see https://github.com/nicolargo/glances/issues/1525)
+        if not os.path.isfile(self.csv_filename) or args.export_csv_overwrite:
+            # File did not exist, create it
+            file_mode = 'w'
+            self.old_header = None
+        else:
+            # A CSV file already exit, append new data
+            file_mode = 'a'
+            # Header will be checked later
+            # Get the existing one
+            try:
+                self.csv_file = open_csv_file(self.csv_filename, 'r')
+                reader = csv.reader(self.csv_file)
+            except IOError as e:
+                logger.critical("Cannot open existing CSV file: {}".format(e))
+                sys.exit(2)
+            self.old_header = next(reader, None)
+            self.csv_file.close()
+
+        try:
+            self.csv_file = open_csv_file(self.csv_filename, file_mode)
+            self.writer = csv.writer(self.csv_file)
+        except IOError as e:
+            logger.critical("Cannot create the CSV file: {}".format(e))
+            sys.exit(2)
+
+        logger.info("Stats exported to CSV file: {}".format(self.csv_filename))
+
+        self.export_enable = True
+
+        self.first_line = True
+
+    def exit(self):
+        """Close the CSV file."""
+        logger.debug("Finalise export interface %s" % self.export_name)
+        self.csv_file.close()
+
+    def update(self, stats):
+        """Update stats in the CSV output file."""
+        # Get the stats
+        all_stats = stats.getAllExportsAsDict(plugin_list=self.plugins_to_export(stats))
+
+        # Init data with timestamp (issue#708)
+        if self.first_line:
+            csv_header = ['timestamp']
+        csv_data = [time.strftime('%Y-%m-%d %H:%M:%S')]
+
+        # Loop over plugins to export
+        for plugin in self.plugins_to_export(stats):
+            if isinstance(all_stats[plugin], list):
+                for stat in sorted(all_stats[plugin], key=lambda x: x['key']):
+                    # First line: header
+                    if self.first_line:
+                        csv_header += ['{}_{}_{}'.format(plugin, self.get_item_key(stat), item) for item in stat]
+                    # Others lines: stats
+                    csv_data += itervalues(stat)
+            elif isinstance(all_stats[plugin], dict):
+                # First line: header
+                if self.first_line:
+                    fieldnames = iterkeys(all_stats[plugin])
+                    csv_header += ('{}_{}'.format(plugin, fieldname) for fieldname in fieldnames)
+                # Others lines: stats
+                csv_data += itervalues(all_stats[plugin])
+
+        # Export to CSV
+        # Manage header
+        if self.first_line:
+            if self.old_header is None:
+                # New file, write the header on top on the CSV file
+                self.writer.writerow(csv_header)
+            # File already exist, check if header are compatible
+            if self.old_header != csv_header and self.old_header is not None:
+                # Header are different, log an error and do not write data
+                logger.error("Cannot append data to existing CSV file. Headers are different.")
+                logger.debug("Old header: {}".format(self.old_header))
+                logger.debug("New header: {}".format(csv_header))
+            else:
+                # Header are equals, ready to write data
+                self.old_header = None
+            # Only do this once
+            self.first_line = False
+        # Manage data
+        if self.old_header is None:
+            self.writer.writerow(csv_data)
+            self.csv_file.flush()
+
+
+def open_csv_file(file_name, file_mode):
+    return open(file_name, file_mode, newline='')