settlement-date plugin

fava_plugins/settlement_date.py

@@ -0,0 +1,69 @@
+"""Beancount plugin to split transactions which are in transit.
+
+It looks through all Transaction entries with the `settlement-date`-metadata on
+one of it's postings and splits those into two transactions.
+
+Example:
+
+    plugin "fava.plugins.settlement_date" "Assets:Savings:Transfer"
+
+    2017-04-01 * "" ""
+        Assets:Savings:US       -100.00 USD
+        Assets:Savings:JP
+            settle: 2017-04-03
+
+    ; becomes
+
+    2017-04-01 * "" "Doing some saving transfers" ^settle-43be1c
+        Assets:Savings:US       -100.00 USD
+        Assets:Savings:Transfer
+            settle: 2017-04-03
+
+    2017-04-03 * "" "Settle: Doing some saving transfers" ^settle-43be1c
+        Assets:Savings:Transfer -100.00 USD
+        Assets:Savings:JP        100.00 USD
+"""
+
+from dateutil.parser import parse
+
+from beancount.core import data, compare
+
+__plugins__ = ['settlement_date']
+
+
+def settlement_date(entries, options_map, config):
+    errors = []
+
+    for index, entry in enumerate(entries):
+        if isinstance(entry, data.Transaction):
+            for p_index, posting in enumerate(entry.postings):
+                if posting.meta and 'settlement-date' in posting.meta:
+                    postings = entry.postings
+                    s_date = posting.meta['settlement-date']
+                    link = 'settle-{}'.format(compare.hash_entry(entry))
+                    original_account = posting.account
+                    entry.postings[p_index] = entry.postings[p_index]._replace(account=config)
+                    links = set(entry.links).union([link]) \
+                            if entry.links else set([link])
+                    entries[index] = entry._replace(postings=postings)
+                    entries[index] = entry._replace(links=links)
+
+                    new_posting = postings[p_index]
+                    new_posting = new_posting._replace(meta=dict())
+
+                    postings = [
+                        new_posting,
+                        new_posting
+                    ]
+
+                    postings[0] = postings[0]._replace(account=config)
+                    postings[0] = postings[0]._replace(units=postings[1].units._replace(number=postings[1].units.number*-1))
+                    postings[1] = postings[1]._replace(account=original_account)
+
+                    entries.append(data.Transaction(entry.meta, s_date,
+                        entry.flag, '', 'Settle: {}'.format(entry.narration),
+                        entry.tags, set([link]), postings))
+
+                    break
+
+    return entries, errors