Likely pertains to helping with stuff in issues #345 and #373 and just
generally is handy to have when processing ledgers / clearing event
tables.
Adds the following helper methods:
- `iter_by_dt()` to iter-sort an arbitrary `Transaction`-like table of
clear entries.
- `Position.iter_clears()` as a convenience wrapper for the above.
This firstly changes `.audit_sizing()` => `.ensure_state()` and makes it
return `None` as well as only error when split ratio denoted (via
config) positions do not size as expected.
Further refinements,
- add an `.expired()` predicate method
- always return a size of zero from `.calc_size()` on expired assets
- load each `pps.toml` entry's clear tabe into `Transaction`s and use
`.add_clear()` during from config init.
In order to avoid issues with reloading ledger and API trades after an
existing `pps.toml` exists we have to make sure we not only avoid
duplicate entries but also avoid re-adding entries that would have been
removed during a prior call to the `Position.minimize_clears()` filter.
The easiest way to do this is to sort on timestamps and avoid adding any
record that pre-existed the last net-zero position ledger event that
`.minimize_clears()` discarded. In order to implement this it means
parsing config file clears table's timestamps into datetime objects for
inequality checks and we add a `Position.first_clear_dt` attr for
storing this value when managing pps in object form but never store it
in the config (since it should be obviously from the sorted clear event
table).
The original implementation of `.calc_be_price()` wasn't correct since
the real so called "price per unit" (ppu), is actually defined by
a recurrence relation (which is why the original state-updated
`.lifo_update()` approach worked well) and requires the previous ppu to
be weighted by the new accumulated position size when considering a new
clear event. The ppu is the price that above or below which the trader
takes a win or loss on transacting one unit of the trading asset and
thus it is the true "break even price" that determines making or losing
money per fill. This patches fixes the implementation to use trailing
windows of the accumulated size and ppu to compute the next ppu value
for any new clear event as well as handle rare cases where the
"direction" changes polarity (eg. long to short in a single order). The
new method is `Position.calc_ppu()` and further details of the relation
can be seen in the doc strings.
This patch also includes a wack-ton of clean ups and removals in an
effort to refine position management api for easier use in new backends:
- drop `updaate_pps_conf()`, `load_pps_from_toml()` and rename
`load_trands_from_ledger()` -> `load_pps_from_ledger()`.
- extend `PpTable` to have a `.to_toml()` method which returns the
active set of positions ready to be serialized to the `pps.toml` file
which is collects from calling,
- `PpTable.dump_active()` which now returns double dicts of the
open/closed pp object maps.
- make `Position.minimize_clears()` now iterate the clears table in
chronological order (instead of reverse) and only drop fills prior
to any zero-size state (the old reversed way can result incorrect
history-size-retracement in cases where a position is lessened but
not completely exited).
- drop `Position.add_clear()` and instead just manually add entries
inside `.update_from_trans()` and also add a `accum_size` and `ppu`
field to ever entry thus creating a position "history" sequence of
the ppu and accum size for every position and prepares for being
and to show "position lifetimes" in the UI.
- move fqsn getting into `Position.to_pretoml()`.
Use the new `.calc_[be_price/size]()` methods when serializing to and
from the `pps.toml` format and add an audit method which will warn about
mismatched values and assign the clears table calculated values pre-write.
Drop the `.lifo_update()` method and instead allow both
`.size`/`.be_price` properties to exist (for non-ledger related uses of
`Position`) alongside the new calc methods and only get fussy about
*what* the properties are set to in the case of ledger audits.
Also changes `Position.update()` -> `.add_clear()`.
Since we're going to need them anyway for desired features, add
2 new `Position` methods:
- `.calc_be_price()` which computes the breakeven cost basis price
from the entries in the clears table.
- `.calc_size()` which just sums the clear sizes.
Add a `cost_scalar: float` control to the `.update_from_trans()` method
to allow manual adjustment of the cost weighting for the case where
a "non-symmetrical" model is wanted.
Go back to always trying to write the backing ledger files on exit, even
when there's an error (obvs without the `return` in the `finally:` block
f$#% up).
Can't believe i missed this but any `return` inside a `finally` will
suppress the error from the `try:` part... XD
Thought i was losing my mind when the ledger was mutated and then
an error just after wasn't getting raised.. lul.
Never again...
In order to avoid double transaction adds/updates and too-early-discard
of zero sized pps (like when trades are loaded from a backend broker but
were already added to a ledger or `pps.toml` prior) we now **don't** pop
such `Position` entries from the `.pps` table in order to keep each
position's clears table always in place. This avoids the edge case where
an entry was removed too early (due to zero size) but then duplicate
trade entries that were in that entrie's clears show up from the backend
and are entered into a new entry resulting in an incorrect size in a new
entry..We still only push non-net-zero entries to the `pps.toml`.
More fixes:
- return the updated set of `Positions` from `.lifo_update()`.
- return the full table set from `update_pps()`.
- use `PpTable.update_from_trans()` more throughout.
- always write the `pps.toml` on `open_pps()` exit.
- only return table from `load_pps_from_toml()`.
In an effort to begin allowing backends to have more granular control
over position updates, particular in the case where they need to be
reloaded from a trades ledger, this adds a new table API which can
be loaded using `open_pps()`.
- offer an `.update_trans()` method which takes in a `dict` of
`Transactions` and updates the current table of `Positions` from it.
- add a `.dump_active()` which renders the active pp entries dict in
a format ready for toml serialization and all closed positions since
the last update (we might want to not drop these?)
All other module-function apis currently in use should remain working as
before for the moment.
This was just implemented totally wrong but somehow worked XD
The idea was to include all trades that contribute to ongoing position
size since the last time the position was "net zero", i.e. no position
in the asset. Adjust arithmetic to *subtract* from the current size
until a zero size condition is met and then keep all those clears as
part of the "current state" clears table.
Additionally this fixes another bug where the positions freshly loaded
from a ledger *were not* being merged with the current `pps.toml` state.
Gah, was a remaining bug where if you tried to update the pps state with
both new trades and from the ledger you'd do a double add of
transactions that were cleared during a `update_pps()` loop. Instead now
keep all clears in tact until ready to serialize to the `pps.toml` file
in which cases we call a new method `Position.minimize_clears()` which
does the work of only keep clears since the last net-zero size.
Re-implement `update_pps_conf()` update logic as a single pass loop
which does expiry and size checking for closed pps all in one pass thus
allowing us to drop `dump_active()` which was kinda redundant anyway..
- use `tomli` package for reading since it's the fastest pure python
reader available apparently.
- add new fields to each pp's clears table: price, size, dt
- make `load_pps_from_toml()`'s `reload_records` a dict that can be
passed in by the caller and is verbatim used to re-read a ledger and
filter to the specified symbol set to build out fresh pp objects.
- add a `update_from_ledger: bool` flag to `load_pps_from_toml()`
to allow forcing a full backend ledger read.
- if a set of trades records is passed into `update_pps_conf()` parse
out the meta data required to cause a ledger reload as per 2 bullets
above.
- return active and closed pps in separate by-account maps from
`update_pps_conf()`.
- drop the `key_by` kwarg.
This makes it possible to refresh a single fqsn-position in one's
`pps.toml` by simply deleting the file entry, in which case, if there is
new trade records passed to `load_pps_from_toml()` via the new
`reload_records` kwarg, then the backend ledger entries matching that
symbol will be filtered and used to recompute a fresh position.
This turns out to be super handy when you have crashes that prevent
a `pps.toml` entry from being updated correctly but where the ledger
does have all the data necessary to calculate a fresh correct entry.
Since some positions obviously expire and thus shouldn't continually
exist inside a `pps.toml` add naive support for tracking and discarding
expired contracts:
- add `Transaction.expiry: Optional[pendulum.datetime]`.
- add `Position.expiry: Optional[pendulum.datetime]` which can be parsed
from a transaction ledger.
- only write pps with a non-none expiry to the `pps.toml`
- change `Position.avg_price` -> `.be_price` (be is "breakeven")
since it's a much less ambiguous name.
- change `load_pps_from_legder()` to *not* call `dump_active()` since
for the only use case it ends up getting called later anyway.
This makes a few major changes but mostly is centered around including
transaction (aka trade-clear) costs in the avg breakeven price
calculation.
TL;DR:
- rename `TradeRecord` -> `Transaction`.
- make `Position.fills` a `dict[str, float]` which holds each clear's
cost value.
- change `Transaction.symkey` -> `.bsuid` for "backend symbol unique id".
- drop `brokername: str` arg to `update_pps()`
- rename `._split_active()` -> `dump_active()` and use input keys
verbatim in output map.
- in `update_pps_conf()` always incrementally update from trade records
even when no `pps.toml` exists yet since it may be both the case that
the ledger needs loading **and** the caller is handing new records not
yet in the ledger.
Begins the position tracking incremental update API which supports both
constructing a `pps.toml` both from trade ledgers as well diff-oriented
incremental update from an existing config assumed to be previously
generated from some prior ledger.
New set of routines includes:
- `_split_active()` a helper to split a position table into the active
and closed positions (aka pps of size 0) for determining entry updates
in the `pps.toml`.
- `update_pps_conf()` to maybe load a `pps.toml` and update it from
an input trades ledger including necessary (de)serialization to and
from `Position` object form(s).
- `load_pps_from_ledger()` a ledger parser-loader which constructs
a table of pps strictly from the broker-account ledger data without
any consideration for any existing pps file.
Each "entry" in `pps.toml` also contains a `fills: list` attr (name may
change) which references the set of trade records which make up its
state since the last net-zero position in the instrument.
Add a `TradeRecord` struct which holds the minimal field set to build
out position entries. Add `.update_pps()` to convert a set of records
into LIFO position entries, optionally allowing for an update to some
existing pp input set. Add `load_pps_from_ledger()` which does a full
ledger extraction to pp objects, ready for writing a `pps.toml`.
Start a generic "position related" util mod and bring in the `Position`
type from the allocator , convert it to a `msgspec.Struct` and add
a `.lifo_update()` method. Implement a WIP pp parser from a trades
ledger and use the new lifo method to gather position entries.