zerodha
¶
Zerodha mapping adapter.
Zerodha lumps almost everything under one flat instrument type per exchange, with no discriminating column of its own. NSE "EQ" covers equities, exchange traded funds, mutual fund plans, investment trusts, and corporate bonds together; BSE "EQ" the same minus the mutual funds; the currency segment covers currency pairs, government bond derivatives, and the overnight rate index together; and the derivative exchanges mix stock and index contracts.
Nothing here is a plain equality match, so this adapter classifies every row itself and the rules file carries no rules at all — only the identity and broker field mappings, which the base class still reads. Classification dispatches on the exchange, segment, and instrument type together, so each row lands in exactly one place.
The NSE flat bucket is decided by the trading symbol's suffix, taken as the last hyphen-separated part rather than the second, since a base symbol can itself contain a hyphen. The BSE flat bucket has no suffix convention and is decided by a sequence of name and symbol heuristics, with the cross-broker fund allowlist checked first: the fixed income heuristics are broad enough to claim a fund ticker otherwise.
Zerodha carries no ISIN column, so both fixed income segments take their identity from the shared security identifier map, keyed on this broker's own exchange token, which sits in the same exchange-assigned numbering the ISIN-bearing brokers use.
Classes:
| Name | Description |
|---|---|
ZerodhaMappingAdapter |
Mapping adapter for Zerodha, covering 30 real segments plus the uncategorised buckets. |
Functions:
| Name | Description |
|---|---|
is_blank |
Check whether a raw value is absent or empty, in any of the forms the raw tables produce. |
normalize_index_name |
Reduce an index name to uppercase alphanumerics so that differently-spelled broker names collide. |
ZerodhaMappingAdapter
¶
Bases: BrokerMappingAdapter
Mapping adapter for Zerodha, covering 30 real segments plus the uncategorised buckets.
Example programs
"""Classifies Zerodha rows, where one instrument type covers equities, bonds, funds and trusts alike.
Zerodha gives every NSE cash row the instrument type EQ, whether it is a share, a government bond, a mutual fund plan or an investment trust, and it has no ISIN column. `ZerodhaMappingAdapter.classify` therefore decides everything in code: on NSE by the trading symbol's suffix (`-GS` is a bond, `-RR` a trust, `-BE` still an equity), on BSE by name and symbol heuristics, and on the derivative exchanges by whether the underlying is an index. A bond is kept only when its exchange token appears in a map from token to ISIN built out of other brokers' files, because the ISIN is its identity; the second bond below is unknown to that map and is left uncategorised.
`to_identity` strips series suffixes, stores bonds under the borrowed ISIN and brings index names to the shared spelling. `to_broker_fields` falls back to the trading symbol where a bond has no name. `classify_extra` gives a BSE row whose name equals its symbol (one of the bond heuristics) its equity membership as well.
`run` normally builds the fund lists, the token map and the index lookup from the database; this program sets them by hand, so no database is needed. `uncategorised_exchange` shows where a dropped row is filed.
Run it from the project root:
python examples/stock_brokers/instruments/mapping/zerodha/ZerodhaMappingAdapter/example_1_one_flat_bucket_many_segments.py
"""
from stock_brokers.instruments.mapping.zerodha import (
ZerodhaMappingAdapter,
)
class OneFlatBucketManySegmentsExample:
"""Classifies eight hand-written Zerodha rows and prints each one's segments, identity and broker symbol.
Attributes:
adapter (ZerodhaMappingAdapter): The adapter being shown.
raw_rows (list): The raw rows, as dictionaries of text columns.
"""
def __init__(self):
"""Builds the adapter, sets the lists and maps `run` would build, and writes the rows.
Returns:
None: This method returns nothing.
"""
self.adapter = ZerodhaMappingAdapter()
self.adapter.nse_fund_symbols = set()
self.adapter.nse_etf_symbols = set()
self.adapter.bse_fund_symbols = set()
self.adapter.bse_trust_symbols = set()
self.adapter.bse_fixed_income_symbols = set()
self.adapter.bse_etf_symbols = set()
self.adapter.nse_index_master_lookup = {}
self.adapter.isin_by_token = {
'15542': 'IN0020160019',
'973412': 'INE530B07393',
}
self.raw_rows = [
self.raw_row('408065', '1594', 'INFY', 'INFOSYS', 'EQ', 'NSE', 'NSE', None, None),
self.raw_row('3677697', '14366', 'IDEA-BE', 'VODAFONE IDEA', 'EQ', 'NSE', 'NSE', None, None),
self.raw_row('3978753', '15542', '762GS2036-GS', None, 'EQ', 'NSE', 'NSE', None, None),
self.raw_row('3982849', '15558', '718GS2033-GS', None, 'EQ', 'NSE', 'NSE', None, None),
self.raw_row('2455041', '9383', 'EMBASSY-RR', 'EMBASSY OFFICE PARKS REIT', 'EQ', 'NSE', 'NSE', None, None),
self.raw_row('260105', '26009', 'NIFTY BANK', 'NIFTY BANK', 'EQ', 'INDICES', 'NSE', None, None),
self.raw_row('12602626', '49229', 'NIFTY26OCT25000CE', 'NIFTY', 'CE', 'NFO-OPT', 'NFO', '2026-10-27', '25000'),
self.raw_row('249193988', '973412', '800IIFL28', '800IIFL28', 'EQ', 'BSE', 'BSE', None, None),
]
def raw_row(self, instrument_token, exchange_token, trading_symbol, name, instrument_type, segment, exchange, expiry, strike):
"""Builds one raw row in the shape of `zerodha.instruments`.
Args:
instrument_token (str): Zerodha's own token.
exchange_token (str): The exchange's token for the row.
trading_symbol (str): The `tradingsymbol` column.
name (str | None): The `name` column, blank on many bonds.
instrument_type (str): EQ, FUT, CE or PE.
segment (str): The `segment` column, such as NSE, INDICES or NFO-OPT.
exchange (str): The `exchange` column.
expiry (str | None): The expiry date as text, for derivatives.
strike (str | None): The strike price, for options.
Returns:
dict: The raw row, every column as text as the raw table stores it.
"""
return {
'instrument_token': instrument_token,
'exchange_token': exchange_token,
'tradingsymbol': trading_symbol,
'name': name,
'expiry': expiry,
'strike': strike,
'tick_size': '0.01',
'lot_size': '1',
'instrument_type': instrument_type,
'segment': segment,
'exchange': exchange,
}
def run(self):
"""Prints each row's segments, identity and broker symbol, or where an unmatched row is filed.
Returns:
None: This method returns nothing.
"""
for raw_row in self.raw_rows:
label = f'{raw_row["exchange"]} {raw_row["tradingsymbol"]} (name {raw_row["name"]})'
segment_configuration = self.adapter.classify(raw_row)
if segment_configuration is None:
exchange = self.adapter.uncategorised_exchange(raw_row)
print(f'{label} -> no segment, filed under {exchange}_uncategorised')
continue
extra_segments = []
for extra_configuration in self.adapter.classify_extra(raw_row):
extra_segments.append(extra_configuration['segment'])
identity = self.adapter.to_identity(raw_row, segment_configuration)
broker_fields = self.adapter.to_broker_fields(raw_row, segment_configuration)
print(f'{label} -> {segment_configuration["segment"]}, also {extra_segments}')
print(f' identity {identity}, broker symbol {broker_fields["broker_symbol"]!r}')
if __name__ == '__main__':
OneFlatBucketManySegmentsExample().run()
It prints:
NSE INFY (name INFOSYS) -> nse_equities, also []
identity {'symbol': 'INFY'}, broker symbol 'INFOSYS'
NSE IDEA-BE (name VODAFONE IDEA) -> nse_equities, also []
identity {'symbol': 'IDEA'}, broker symbol 'VODAFONE IDEA'
NSE 762GS2036-GS (name None) -> nse_fixed_income, also []
identity {'symbol': 'IN0020160019'}, broker symbol '762GS2036-GS'
NSE 718GS2033-GS (name None) -> no segment, filed under nse_uncategorised
NSE EMBASSY-RR (name EMBASSY OFFICE PARKS REIT) -> nse_investment_trusts, also []
identity {'symbol': 'EMBASSY'}, broker symbol 'EMBASSY OFFICE PARKS REIT'
NSE NIFTY BANK (name NIFTY BANK) -> nse_equity_indices, also []
identity {'symbol': 'BANKNIFTY'}, broker symbol 'NIFTY BANK'
NFO NIFTY26OCT25000CE (name NIFTY) -> nse_equity_index_options, also []
identity {'underlying_symbol': 'NIFTY', 'expiry_date': datetime.date(2026, 10, 27), 'strike_price': 25000.0, 'option_type': 'CE'}, broker symbol 'NIFTY26OCT25000CE'
BSE 800IIFL28 (name 800IIFL28) -> bse_fixed_income, also ['bse_equities']
identity {'symbol': 'INE530B07393'}, broker symbol '800IIFL28'
"""Maps one day of Zerodha rows, gathering every list and map it needs from the other brokers first.
`ZerodhaMappingAdapter.run` first gathers six fund, trust and bond symbol lists from the other brokers' tables, builds a map from exchange token to ISIN out of the brokers that publish ISINs, and reads the NSE index names already stored in `unified.instruments`. It then hands over to the shared mapping run, which reads Zerodha's raw rows, classifies them, and writes `unified.instruments` and `unified.broker_mappings` in one transaction.
The adapter normally talks to PostgreSQL, so this program replaces its `engine` with a stand-in. The stand-in connection answers queries by matching a piece of their text: the raw-row query gets four hand-written Zerodha rows, and Groww's token and ISIN query knows the NSE bond. Every other cross-broker query gets no rows, and every write is recorded instead of run. pandas only reads through something it recognises as an SQLAlchemy connectable, and it recognises one by the `ConnectionEventsTarget` base class, so the stand-in connection inherits from that class.
Notice the summary: four raw rows give five segment memberships but only four instruments. `classify_extra` returns the equity segment for every ordinary BSE equity, including one already classified as an equity, so RELIANCE is counted twice and written once. Notice also that the uncategorised bond's broker symbol is `nan`: pandas turns the blank name into a missing number when it reads the rows, and only the bond segments fall back to the trading symbol.
Run it from the project root:
python examples/stock_brokers/instruments/mapping/zerodha/ZerodhaMappingAdapter/example_2_mapping_one_day.py
"""
import collections
import datetime
from sqlalchemy.engine import interfaces
from stock_brokers.instruments.mapping.zerodha import (
ZerodhaMappingAdapter,
)
class StandInResult:
"""A stand-in for an SQLAlchemy result holding a fixed set of rows.
Attributes:
columns (list): The column names.
rows (list): The rows, as dictionaries.
"""
def __init__(self, rows):
"""Holds the rows.
Args:
rows (list): The rows, as dictionaries that all share the same keys.
Returns:
None: This method returns nothing.
"""
self.rows = rows
self.columns = []
if rows:
self.columns = list(rows[0])
def keys(self):
"""The column names, as pandas asks for them.
Returns:
list: The column names.
"""
return self.columns
def fetchall(self):
"""Every row as a plain tuple, as pandas asks for them.
Returns:
list: The rows as tuples in column order.
"""
tuples = []
for row in self.rows:
tuples.append(tuple(row.values()))
return tuples
def all(self):
"""Every row as a named tuple, so a column can be read as an attribute.
Returns:
list: The rows as named tuples.
"""
row_type = collections.namedtuple('StandInRow', self.columns)
named_rows = []
for row in self.rows:
named_rows.append(row_type(**row))
return named_rows
class StandInConnection(interfaces.ConnectionEventsTarget):
"""A stand-in for a PostgreSQL connection that answers queries from prepared rows and records writes.
Attributes:
answers (list): Pairs of (a piece of query text, the rows to answer with).
unanswered_queries (int): How many queries matched no prepared answer and got no rows.
writes (list): Each write statement's first words and its parameters.
"""
def __init__(self, answers):
"""Holds the prepared answers and starts with nothing recorded.
Args:
answers (list): Pairs of (a piece of query text, the rows to answer with).
Returns:
None: This method returns nothing.
"""
self.answers = answers
self.unanswered_queries = 0
self.writes = []
def __enter__(self):
"""Opens the connection for a `with` block.
Returns:
StandInConnection: This connection.
"""
return self
def __exit__(self, exception_type, exception, traceback):
"""Closes the connection at the end of a `with` block.
Args:
exception_type (type | None): The type of any exception raised in the block.
exception (BaseException | None): Any exception raised in the block.
traceback (object | None): The traceback of any exception raised in the block.
Returns:
bool: False, so any exception carries on.
"""
return False
def execute(self, statement, parameters=None):
"""Answers a query from the prepared rows, or records a write.
Args:
statement (sqlalchemy.sql.elements.TextClause): The statement to run.
parameters (dict | list | None): Its bound parameters.
Returns:
StandInResult: The prepared rows whose text matches, otherwise an empty result.
"""
sql = ' '.join(str(statement).split())
if not sql.startswith('SELECT'):
self.writes.append((' '.join(sql.split()[:3]), parameters))
return StandInResult([])
for query_text, rows in self.answers:
if query_text in sql:
return StandInResult(rows)
self.unanswered_queries += 1
return StandInResult([])
class StandInEngine:
"""A stand-in for an SQLAlchemy engine that always hands out the same stand-in connection.
Attributes:
connection (StandInConnection): The connection handed out.
"""
def __init__(self, connection):
"""Holds the connection to hand out.
Args:
connection (StandInConnection): The connection handed out.
Returns:
None: This method returns nothing.
"""
self.connection = connection
def connect(self):
"""Hands out the connection for reading.
Returns:
StandInConnection: The connection.
"""
return self.connection
def begin(self):
"""Hands out the connection for one transaction.
Returns:
StandInConnection: The connection.
"""
return self.connection
class MappingOneDayExample:
"""Maps four Zerodha rows for one date and prints what would be written.
Attributes:
mapping_date (datetime.date): The snapshot date being mapped.
connection (StandInConnection): The stand-in connection.
adapter (ZerodhaMappingAdapter): The adapter being shown, using the stand-in engine.
"""
def __init__(self):
"""Builds the adapter and swaps its engine for the stand-in.
Returns:
None: This method returns nothing.
"""
self.mapping_date = datetime.date(2026, 9, 28)
raw_rows = [
self.raw_row('408065', '1594', 'INFY', 'INFOSYS', 'NSE'),
self.raw_row('3978753', '15542', '762GS2036-GS', None, 'NSE'),
self.raw_row('3982849', '15558', '718GS2033-GS', None, 'NSE'),
self.raw_row('128083204', '500325', 'RELIANCE', 'RELIANCE INDUSTRIES', 'BSE'),
]
groww_isins = [
{
'exchange_token': '15542',
'isin': 'IN0020160019',
},
]
answers = [
(
'SELECT * FROM zerodha.instruments',
raw_rows,
),
(
'SELECT exchange_token, isin FROM groww.instruments',
groww_isins,
),
]
self.connection = StandInConnection(answers)
self.adapter = ZerodhaMappingAdapter()
self.adapter.engine = StandInEngine(self.connection)
def raw_row(self, instrument_token, exchange_token, trading_symbol, name, exchange):
"""Builds one cash-market raw row in the shape of `zerodha.instruments`.
Args:
instrument_token (str): Zerodha's own token.
exchange_token (str): The exchange's token for the row.
trading_symbol (str): The `tradingsymbol` column.
name (str | None): The `name` column, blank on many bonds.
exchange (str): NSE or BSE, which is also the segment for cash rows.
Returns:
dict: The raw row, every column as text as the raw table stores it.
"""
return {
'instrument_token': instrument_token,
'exchange_token': exchange_token,
'tradingsymbol': trading_symbol,
'name': name,
'last_price': '0',
'expiry': None,
'strike': '0',
'tick_size': '0.01',
'lot_size': '1',
'instrument_type': 'EQ',
'segment': exchange,
'exchange': exchange,
'download_date': self.mapping_date,
}
def run(self):
"""Maps the day and prints the summary and the rows written.
Returns:
None: This method returns nothing.
"""
summary = self.adapter.run(self.mapping_date)
print(f'Token to ISIN map: {self.adapter.isin_by_token}')
print(f'Cross-broker queries that found nothing: {self.connection.unanswered_queries}')
print(f'Summary: raw rows {summary["raw_rows"]}, matched {summary["matched"]}, uncategorised {summary["uncategorised"]}, memberships {summary["memberships"]}, instruments {summary["instruments_upserted"]}')
for statement, parameters in self.connection.writes:
print(statement)
if not isinstance(parameters, list):
continue
for row in parameters:
if 'segment' in row:
print(f' {row["segment"]}: {row["symbol"]}')
else:
print(f' token {row["broker_token"]}: {row["broker_symbol"]}')
if __name__ == '__main__':
MappingOneDayExample().run()
It prints:
zerodha: 3/4 raw row(s) classified, 1 uncategorised, 5 segment membership(s), 4 distinct instrument(s), 0 error(s).
Token to ISIN map: {'15542': 'IN0020160019'}
Cross-broker queries that found nothing: 36
Summary: raw rows 4, matched 3, uncategorised 1, memberships 5, instruments 4
DELETE FROM unified.broker_mappings
INSERT INTO unified.instruments
nse_uncategorised: 718GS2033-GS
nse_fixed_income: IN0020160019
bse_equities: RELIANCE
nse_equities: INFY
INSERT INTO unified.broker_mappings
token 3982849: nan
token 3978753: 762GS2036-GS
token 128083204: RELIANCE INDUSTRIES
token 408065: INFOSYS
Load and validate the broker's rules file and create the database engine.
Raises:
| Type | Description |
|---|---|
NotImplementedError
|
If the subclass did not set BROKER_NAME. |
ValueError
|
If the rules file fails validation. |
FileNotFoundError
|
If the broker has no rules file. |
Example programs
"""Classifies three raw instrument rows using nothing but a broker's rules file.
`BrokerMappingAdapter` is the base class every broker's mapping adapter subclasses. A subclass only has to name its broker in `BROKER_NAME`, and the base class loads the matching rules file from `stock_brokers/instruments/mapping/utilities/rules/`, checks it against the canonical segment vocabulary, and classifies rows by plain equality rules. This program's subclass sets `BROKER_NAME` to Dhan and overrides nothing, so every answer below comes from the base class and Dhan's rules file alone, without the extra filters the real `DhanMappingAdapter` adds.
The rows are written out by hand in the shape of `dhan.instruments`, where every column is text. The adapter builds a database engine when it is constructed, but an engine does not connect until it is used, and this program never asks it to, so nothing touches PostgreSQL.
For each row the program prints the segment the rules chose, any extra segments (the base class never adds any), the identity fields that go into the instrument id, the broker's own fields, and the deterministic instrument id. The third row matches no rule. The base class cannot tell which exchange it belongs to, so it falls into the unprefixed `uncategorised` segment, and the run would store its token as its symbol.
Run it from the project root:
python examples/stock_brokers/instruments/mapping/base/BrokerMappingAdapter/example_1_classifying_rows_by_rules.py
"""
from stock_brokers.instruments.mapping import base
from stock_brokers.instruments.mapping.base import (
BrokerMappingAdapter,
)
class DhanRulesOnlyAdapter(BrokerMappingAdapter):
"""A mapping adapter that uses Dhan's rules file and nothing but the base class's behaviour."""
BROKER_NAME = 'dhan'
class ClassifyingRowsByRulesExample:
"""Runs three hand-written Dhan rows through the base class's rules engine and prints the result.
Attributes:
adapter (DhanRulesOnlyAdapter): The adapter being shown.
raw_rows (list): The raw rows to classify, as dictionaries of text columns.
"""
def __init__(self):
"""Builds the adapter and the three raw rows.
Returns:
None: This method returns nothing.
"""
self.adapter = DhanRulesOnlyAdapter()
self.raw_rows = [
{
'exch_id': 'NSE',
'segment': 'E',
'security_id': '1594',
'isin': 'INE009A01021',
'instrument': 'EQUITY',
'underlying_symbol': 'INFY',
'symbol_name': 'INFOSYS LIMITED',
'display_name': 'Infosys',
'instrument_type': 'ES',
'series': 'EQ',
'lot_size': '1.0',
'sm_expiry_date': None,
'strike_price': None,
'option_type': None,
'tick_size': '10.0',
},
{
'exch_id': 'NSE',
'segment': 'D',
'security_id': '40215',
'isin': None,
'instrument': 'OPTIDX',
'underlying_symbol': 'NIFTY',
'symbol_name': 'NIFTY-Oct2026-25000-CE',
'display_name': 'NIFTY 27 OCT 25000 CALL',
'instrument_type': 'OP',
'series': None,
'lot_size': '75.0',
'sm_expiry_date': '2026-10-27',
'strike_price': '25000.00000',
'option_type': 'CE',
'tick_size': '5.0',
},
{
'exch_id': 'NSE',
'segment': 'X',
'security_id': '990001',
'isin': None,
'instrument': 'SPREAD',
'underlying_symbol': '',
'symbol_name': 'TEST SPREAD',
'display_name': 'Test spread',
'instrument_type': 'SP',
'series': None,
'lot_size': '1.0',
'sm_expiry_date': None,
'strike_price': None,
'option_type': None,
'tick_size': '0',
},
]
def run(self):
"""Prints how the rules file classifies each row.
Returns:
None: This method returns nothing.
"""
equities = self.adapter.segment_config('nse_equities')
print(f'Rules file: {self.adapter.config["raw_table"]}, {len(self.adapter.config["segments"])} segments')
print(f'nse_equities is a {equities["shape"]} on {equities["exchange"]} with {len(equities["rules"])} rules')
print(f'Unconfigured segment: {self.adapter.segment_config("nse_bonds")}')
for raw_row in self.raw_rows:
print()
print(f'Row {raw_row["security_id"]} ({raw_row["symbol_name"]})')
segment_configuration = self.adapter.classify(raw_row)
if segment_configuration is None:
exchange = self.adapter.uncategorised_exchange(raw_row)
print(f' No rule matched, and the base class finds no exchange: {exchange}')
segment_configuration = self.adapter.segment_config('uncategorised')
extra_segments = self.adapter.classify_extra(raw_row)
identity = self.adapter.to_identity(raw_row, segment_configuration)
broker_fields = self.adapter.to_broker_fields(raw_row, segment_configuration)
identifier = base.instrument_id(
segment_configuration['exchange'],
segment_configuration['segment'],
segment_configuration['shape'],
identity,
)
print(f' Segment: {segment_configuration["segment"]} ({segment_configuration["shape"]})')
print(f' Extra segments: {extra_segments}')
print(f' Identity: {identity}')
print(f' Broker fields: {broker_fields}')
print(f' Instrument id: {identifier}')
if __name__ == '__main__':
ClassifyingRowsByRulesExample().run()
It prints:
Rules file: dhan.instruments, 32 segments
nse_equities is a security on nse with 2 rules
Unconfigured segment: None
Row 1594 (INFOSYS LIMITED)
Segment: nse_equities (security)
Extra segments: []
Identity: {'symbol': 'INFY'}
Broker fields: {'broker_token': '1594', 'broker_symbol': 'Infosys', 'order_symbol': None, 'lot_size': 1.0, 'tick_size': 0.1}
Instrument id: f310e1b0-e082-5b16-808a-25f741abb9de
Row 40215 (NIFTY-Oct2026-25000-CE)
Segment: nse_equity_index_options (option)
Extra segments: []
Identity: {'underlying_symbol': 'NIFTY', 'expiry_date': datetime.date(2026, 10, 27), 'strike_price': 25000.0, 'option_type': 'CE'}
Broker fields: {'broker_token': '40215', 'broker_symbol': 'NIFTY-Oct2026-25000-CE', 'order_symbol': None, 'lot_size': 75.0, 'tick_size': 0.05}
Instrument id: fe85c704-ce49-5190-b068-d4d3646ed162
Row 990001 (TEST SPREAD)
No rule matched, and the base class finds no exchange: None
Segment: uncategorised (security)
Extra segments: []
Identity: {'symbol': ''}
Broker fields: {'broker_token': '990001', 'broker_symbol': 'Test spread', 'order_symbol': None, 'lot_size': 1.0, 'tick_size': None}
Instrument id: 55a8952d-9071-5670-a4fe-a5384d3876bd
"""Maps one day's raw rows into the two unified tables, against a stand-in database.
`run` is what the daily mapping job calls for each broker. It reads the broker's raw rows for one date with `read_raw_rows`, classifies each row, and then, inside one transaction, deletes that broker's mappings for the date and upserts one row per instrument into `unified.instruments` and one per broker mapping into `unified.broker_mappings`. It returns a summary and prints a one-line report.
The adapter normally reads and writes PostgreSQL, so this program replaces its `engine` with a small stand-in. The stand-in connection answers the raw-row query with four hand-written rows in the shape of `dhan.instruments`, and records every other statement it is sent instead of running it. pandas only reads through something it recognises as an SQLAlchemy connectable, and it recognises one by the `ConnectionEventsTarget` base class, so the stand-in connection inherits from that class and nothing else.
The subclass uses Dhan's rules file and overrides nothing. The fourth row has a strike price that is not a number, so building its identity fails; `run` records that as an error and carries on with the other rows rather than stopping. The unmatched row is stored under its token as its symbol, and its tick size of 5.0 is kept as written, because Dhan's rules divide the tick size by 100 only in the real segments and not in the uncategorised one. The last lines show that a subclass which forgets to set `BROKER_NAME` cannot be built.
Run it from the project root:
python examples/stock_brokers/instruments/mapping/base/BrokerMappingAdapter/example_2_mapping_one_day.py
"""
import datetime
from sqlalchemy.engine import interfaces
from stock_brokers.instruments.mapping.base import (
BrokerMappingAdapter,
)
class DhanRulesOnlyAdapter(BrokerMappingAdapter):
"""A mapping adapter that uses Dhan's rules file and nothing but the base class's behaviour."""
BROKER_NAME = 'dhan'
class UnnamedAdapter(BrokerMappingAdapter):
"""A mapping adapter that forgets to name its broker."""
class StandInResult:
"""A stand-in for an SQLAlchemy result holding a fixed set of rows.
Attributes:
columns (list): The column names.
rows (list): The rows, as tuples in column order.
"""
def __init__(self, columns, rows):
"""Holds the columns and rows.
Args:
columns (list): The column names.
rows (list): The rows, as tuples in column order.
Returns:
None: This method returns nothing.
"""
self.columns = columns
self.rows = rows
def keys(self):
"""The column names, as pandas asks for them.
Returns:
list: The column names.
"""
return self.columns
def fetchall(self):
"""Every row, as pandas asks for them.
Returns:
list: The rows.
"""
return self.rows
def all(self):
"""Every row, as the adapter's own queries ask for them.
Returns:
list: The rows.
"""
return self.rows
class StandInConnection(interfaces.ConnectionEventsTarget):
"""A stand-in for a PostgreSQL connection that serves one raw table and records every other statement.
Attributes:
raw_table (str): The raw table whose rows this connection serves.
raw_rows (list): The raw rows, as dictionaries of column values.
statements (list): Each recorded statement's first line and its parameters.
"""
def __init__(self, raw_table, raw_rows):
"""Holds the raw rows and starts with no statements recorded.
Args:
raw_table (str): The raw table whose rows this connection serves.
raw_rows (list): The raw rows, as dictionaries of column values.
Returns:
None: This method returns nothing.
"""
self.raw_table = raw_table
self.raw_rows = raw_rows
self.statements = []
def __enter__(self):
"""Opens the connection for a `with` block.
Returns:
StandInConnection: This connection.
"""
return self
def __exit__(self, exception_type, exception, traceback):
"""Closes the connection at the end of a `with` block.
Args:
exception_type (type | None): The type of any exception raised in the block.
exception (BaseException | None): Any exception raised in the block.
traceback (object | None): The traceback of any exception raised in the block.
Returns:
bool: False, so any exception carries on.
"""
return False
def execute(self, statement, parameters=None):
"""Answers the raw-row query from the held rows and records anything else.
Args:
statement (sqlalchemy.sql.elements.TextClause): The statement to run.
parameters (dict | list | None): Its bound parameters.
Returns:
StandInResult: The raw rows for the raw-row query, otherwise an empty result.
"""
sql = ' '.join(str(statement).split())
if sql.startswith(f'SELECT * FROM {self.raw_table} '):
columns = list(self.raw_rows[0])
rows = []
for raw_row in self.raw_rows:
values = []
for column in columns:
values.append(raw_row[column])
rows.append(tuple(values))
return StandInResult(columns, rows)
self.statements.append((sql, parameters))
return StandInResult([], [])
class StandInEngine:
"""A stand-in for an SQLAlchemy engine that always hands out the same stand-in connection.
Attributes:
connection (StandInConnection): The connection handed out.
"""
def __init__(self, connection):
"""Holds the connection to hand out.
Args:
connection (StandInConnection): The connection handed out.
Returns:
None: This method returns nothing.
"""
self.connection = connection
def connect(self):
"""Hands out the connection for reading.
Returns:
StandInConnection: The connection.
"""
return self.connection
def begin(self):
"""Hands out the connection for one transaction.
Returns:
StandInConnection: The connection.
"""
return self.connection
class MappingOneDayExample:
"""Maps four raw rows for one date and prints what would be written.
Attributes:
mapping_date (datetime.date): The snapshot date being mapped.
connection (StandInConnection): The stand-in connection holding the raw rows.
adapter (DhanRulesOnlyAdapter): The adapter being shown, using the stand-in engine.
"""
def __init__(self):
"""Builds the adapter and swaps its engine for the stand-in.
Returns:
None: This method returns nothing.
"""
self.mapping_date = datetime.date(2026, 9, 28)
raw_rows = [
self.raw_row('1594', 'NSE', 'E', 'EQUITY', 'ES', 'INFY', 'INFOSYS LIMITED', None, None, None),
self.raw_row('40215', 'NSE', 'D', 'OPTIDX', 'OP', 'NIFTY', 'NIFTY-Oct2026-25000-CE', '2026-10-27', '25000.00000', 'CE'),
self.raw_row('990001', 'NSE', 'X', 'SPREAD', 'SP', '', 'TEST SPREAD', None, None, None),
self.raw_row('40216', 'NSE', 'D', 'OPTIDX', 'OP', 'NIFTY', 'NIFTY-Oct2026-XX-PE', '2026-10-27', 'not a number', 'PE'),
]
self.connection = StandInConnection('dhan.instruments', raw_rows)
self.adapter = DhanRulesOnlyAdapter()
self.adapter.engine = StandInEngine(self.connection)
def raw_row(self, security_id, exchange, segment, instrument, instrument_type, underlying_symbol, symbol_name, expiry, strike_price, option_type):
"""Builds one raw row in the shape of `dhan.instruments`.
Args:
security_id (str): Dhan's token for the row.
exchange (str): The `exch_id` column.
segment (str): Dhan's one-letter segment code.
instrument (str): The `instrument` column.
instrument_type (str): The `instrument_type` column.
underlying_symbol (str): The `underlying_symbol` column.
symbol_name (str): The `symbol_name` column.
expiry (str | None): The `sm_expiry_date` column.
strike_price (str | None): The `strike_price` column.
option_type (str | None): The `option_type` column.
Returns:
dict: The raw row, every column as text as the raw table stores it.
"""
return {
'exch_id': exchange,
'segment': segment,
'security_id': security_id,
'isin': None,
'instrument': instrument,
'underlying_security_id': None,
'underlying_symbol': underlying_symbol,
'symbol_name': symbol_name,
'display_name': symbol_name,
'instrument_type': instrument_type,
'series': None,
'lot_size': '1.0',
'sm_expiry_date': expiry,
'strike_price': strike_price,
'option_type': option_type,
'tick_size': '5.0',
'download_date': self.mapping_date,
}
def short_row(self, row):
"""Shortens one written row to its filled-in columns, leaving out the dates the example already names.
Args:
row (dict): One row the adapter asked to insert.
Returns:
dict: The row's columns that hold a value, with the instrument id cut to its first eight characters.
"""
shortened = {}
for column, value in row.items():
if value is None or isinstance(value, datetime.date):
continue
if column == 'instrument_id':
value = value[:8]
shortened[column] = value
return shortened
def run(self):
"""Reads the raw rows, maps them, and prints the summary and the statements sent.
Returns:
None: This method returns nothing.
"""
raw = self.adapter.read_raw_rows(self.connection, self.mapping_date)
print(f'read_raw_rows returned {len(raw)} rows with {len(raw.columns)} columns')
print()
summary = self.adapter.run(self.mapping_date)
print()
for key in summary:
print(f'{key}: {summary[key]}')
print()
print('Statements sent inside the write transaction:')
for sql, parameters in self.connection.statements:
print(f' {sql[:60]}...')
if isinstance(parameters, list):
for row in parameters:
print(f' {self.short_row(row)}')
else:
print(f' {parameters}')
print()
try:
UnnamedAdapter()
except NotImplementedError as error:
print(f'NotImplementedError: {error}')
if __name__ == '__main__':
MappingOneDayExample().run()
It prints:
read_raw_rows returned 4 rows with 17 columns
dhan: 3/4 raw row(s) classified, 1 uncategorised, 3 segment membership(s), 3 distinct instrument(s), 1 error(s).
broker: dhan
mapping_date: 2026-09-28
raw_rows: 4
matched: 3
uncategorised: 1
memberships: 3
instruments_upserted: 3
errors: [('nse_equity_index_options', "could not convert string to float: 'not a number'")]
Statements sent inside the write transaction:
DELETE FROM unified.broker_mappings WHERE broker = :b AND ma...
{'b': 'dhan', 'd': datetime.date(2026, 9, 28)}
INSERT INTO unified.instruments AS master (instrument_id, ex...
{'instrument_id': '8fdcd38e', 'exchange': 'unknown', 'segment': 'uncategorised', 'shape': 'security', 'symbol': '990001'}
{'instrument_id': 'f310e1b0', 'exchange': 'nse', 'segment': 'nse_equities', 'shape': 'security', 'symbol': 'INFY'}
{'instrument_id': 'fe85c704', 'exchange': 'nse', 'segment': 'nse_equity_index_options', 'shape': 'option', 'underlying_symbol': 'NIFTY', 'strike_price': 25000.0, 'option_type': 'CE'}
INSERT INTO unified.broker_mappings (instrument_id, broker, ...
{'instrument_id': '8fdcd38e', 'broker': 'dhan', 'broker_token': '990001', 'broker_symbol': 'TEST SPREAD', 'lot_size': 1.0, 'tick_size': 5.0, 'attributes': '{"display_name": "TEST SPREAD", "instrument_type": "SP"}'}
{'instrument_id': 'f310e1b0', 'broker': 'dhan', 'broker_token': '1594', 'broker_symbol': 'INFOSYS LIMITED', 'lot_size': 1.0, 'tick_size': 0.05, 'attributes': '{"display_name": "INFOSYS LIMITED", "instrument_type": "ES"}'}
{'instrument_id': 'fe85c704', 'broker': 'dhan', 'broker_token': '40215', 'broker_symbol': 'NIFTY-Oct2026-25000-CE', 'lot_size': 1.0, 'tick_size': 0.05, 'attributes': '{"display_name": "NIFTY-Oct2026-25000-CE", "instrument_type": "OP"}'}
NotImplementedError: UnnamedAdapter must set BROKER_NAME
Methods:
| Name | Description |
|---|---|
run |
Map Zerodha's raw rows for one date, precomputing the six allowlists, the ISIN map, and the index lookup first. |
classify |
Classify a raw row, then check that a bond row can actually be identified. |
classify_extra |
Return the equity membership a BSE cash-market row also has when it meets the equity criteria in its own right. |
to_identity |
Build the unified identity fields, resolving bond ISINs, stripping series suffixes, and aliasing index names. |
to_broker_fields |
Build the per-broker mapping fields, falling back to the trading symbol where the name is blank. |
uncategorised_exchange |
Determine the canonical exchange for an unmatched Zerodha row from its exchange column. |
segment_config |
Look up one segment configuration by its segment value. |
read_raw_rows |
Read the broker's raw rows for one date. |
Source code in stock_brokers/instruments/mapping/base.py
run
¶
Map Zerodha's raw rows for one date, precomputing the six allowlists, the ISIN map, and the index lookup first.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
mapping_date
|
date
|
The raw snapshot date to map. |
required |
Returns:
| Type | Description |
|---|---|
dict
|
The run summary, as described in BrokerMappingAdapter.run. |
Example usage
Source code in stock_brokers/instruments/mapping/zerodha.py
classify
¶
Classify a raw row, then check that a bond row can actually be identified.
Both fixed income segments take their identity from the shared security identifier map, so a row that map cannot resolve has no identity to be written under. It is left for the uncategorised bucket rather than dropped, which keeps the run's coverage reconciling: on a date where only this broker was downloaded, the map is empty and every bond row lands there.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
Returns:
| Type | Description |
|---|---|
dict | None
|
The matched segment configuration, or None when no segment matches or a bond row cannot be identified. |
Example usage
segment_configuration = self.adapter.classify(raw_row)
Source code in stock_brokers/instruments/mapping/zerodha.py
_classify_by_exchange
¶
Dispatch a raw row on its exchange, segment, and instrument type together.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
Returns:
| Type | Description |
|---|---|
dict | None
|
The matched segment configuration, or None when no segment matches. |
Source code in stock_brokers/instruments/mapping/zerodha.py
_classify_nse_flat
¶
Route an NSE cash-market row, which shares one instrument type across five segments, by its trading symbol suffix.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
Returns:
| Type | Description |
|---|---|
dict | None
|
The matched segment configuration, or None. |
Source code in stock_brokers/instruments/mapping/zerodha.py
_classify_nse_index
¶
Route an NSE index row, excluding the bond-shaped and foreign reference rows that are not equity indices.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
Returns:
| Type | Description |
|---|---|
dict | None
|
The index segment configuration, or None. |
Source code in stock_brokers/instruments/mapping/zerodha.py
_classify_bse_flat
¶
Route a BSE cash-market row, which has no suffix convention, by name and symbol heuristics.
The cross-broker fund check runs first: the fixed income heuristics below are broad — a blank name with any digit in the symbol is one of them — and would otherwise claim a fund ticker such as "GSEC10ADD".
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
Returns:
| Type | Description |
|---|---|
dict | None
|
The matched segment configuration, or None. |
Source code in stock_brokers/instruments/mapping/zerodha.py
_is_bse_fixed_income
¶
Check the heuristics that mark a BSE cash-market row as a bond.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
trading_symbol
|
str
|
The row's trading symbol. |
required |
name
|
str | None
|
The row's name column. |
required |
name_is_blank
|
bool
|
Whether the name is absent. |
required |
Returns:
| Type | Description |
|---|---|
bool
|
True when the row looks like a bond. |
Source code in stock_brokers/instruments/mapping/zerodha.py
classify_extra
¶
Return the equity membership a BSE cash-market row also has when it meets the equity criteria in its own right.
A BSE row can meet more than one segment's criteria, so one row can belong to two segments at once. Of the Zerodha BSE rows whose name equals their trading symbol — one of the bond heuristics — a substantial minority are also genuinely equities. This re-checks the equity criteria independently of what the primary classification chose.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
Returns:
| Type | Description |
|---|---|
list[dict]
|
The equity segment configuration, or an empty list. |
Example usage
Source code in stock_brokers/instruments/mapping/zerodha.py
_classify_nse_derivatives
¶
Route an NSE derivative row, splitting stock from index contracts by the underlying name.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
instrument_type
|
str
|
The row's instrument type. |
required |
Returns:
| Type | Description |
|---|---|
dict | None
|
The matched segment configuration, or None. |
Source code in stock_brokers/instruments/mapping/zerodha.py
_classify_bse_derivatives
¶
Route a BSE derivative row, which this broker's file carries for index contracts only.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
instrument_type
|
str
|
The row's instrument type. |
required |
Returns:
| Type | Description |
|---|---|
dict | None
|
The matched segment configuration, or None. |
Source code in stock_brokers/instruments/mapping/zerodha.py
_classify_mcx
¶
Route an MCX row, splitting commodity from commodity index contracts by the underlying name.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
segment
|
str
|
The row's segment column. |
required |
Returns:
| Type | Description |
|---|---|
dict | None
|
The matched segment configuration, or None. |
Source code in stock_brokers/instruments/mapping/zerodha.py
_classify_nse_commodities
¶
Route an NSE commodity row, a segment only this broker's file carries.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
instrument_type
|
str
|
The row's instrument type. |
required |
Returns:
| Type | Description |
|---|---|
dict | None
|
The matched segment configuration, or None. |
Source code in stock_brokers/instruments/mapping/zerodha.py
_classify_currency_derivatives
¶
Route a currency-segment row, which mixes currency pairs, government bond derivatives, and the overnight rate index.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
instrument_type
|
str
|
The row's instrument type. |
required |
Returns:
| Type | Description |
|---|---|
dict | None
|
The matched segment configuration, or None. |
Source code in stock_brokers/instruments/mapping/zerodha.py
to_identity
¶
Build the unified identity fields, resolving bond ISINs, stripping series suffixes, and aliasing index names.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
segment_configuration
|
dict
|
The segment configuration whose identity mapping applies. |
required |
Returns:
| Type | Description |
|---|---|
dict
|
Identity fields, as described in BrokerMappingAdapter.to_identity. |
Raises:
| Type | Description |
|---|---|
ValueError
|
If a bond row's exchange token has no match in the shared security identifier map, since the ISIN is that segment's identity. |
Example usage
identity = self.adapter.to_identity(raw_row, segment_configuration)
Source code in stock_brokers/instruments/mapping/zerodha.py
to_broker_fields
¶
Build the per-broker mapping fields, falling back to the trading symbol where the name is blank.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
segment_configuration
|
dict
|
The segment configuration whose broker field mapping applies. |
required |
Returns:
| Type | Description |
|---|---|
dict
|
Keys "broker_token" (str), "broker_symbol", "lot_size" (float | None), and "tick_size" (float | None). |
Example usage
broker_fields = self.adapter.to_broker_fields(raw_row, segment_configuration)
Source code in stock_brokers/instruments/mapping/zerodha.py
uncategorised_exchange
¶
Determine the canonical exchange for an unmatched Zerodha row from its exchange column.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from zerodha.instruments. |
required |
Returns:
| Type | Description |
|---|---|
str | None
|
"nse", "bse", or "mcx", or None for any other value. |
Example usage
exchange = self.adapter.uncategorised_exchange(raw_row)
Source code in stock_brokers/instruments/mapping/zerodha.py
_validate_config
¶
Check the loaded rules file against the canonical vocabulary.
Every configured segment must be a real canonical segment for its exchange with the matching shape, and the segments must appear in the canonical asset-class order. The file must end with the unprefixed uncategorised entry on exchange unknown, which is the guaranteed fallback for rows whose exchange cannot be determined; unknown is allowed for that one entry only, since it is the value stored in the exchange column of the mapped table for those rows.
Raises:
| Type | Description |
|---|---|
ValueError
|
On any invalid exchange, segment, shape, ordering, or missing or misplaced uncategorised entry. |
Source code in stock_brokers/instruments/mapping/base.py
segment_config
¶
Look up one segment configuration by its segment value.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
segment
|
str
|
The exchange-prefixed segment value, for example "nse_equities". |
required |
Returns:
| Type | Description |
|---|---|
dict | None
|
The matching segment configuration, or None when the rules file does not configure that segment. |
Example usage
segment_configuration = self.adapter.segment_config('uncategorised')
print(f'Unconfigured segment: {self.adapter.segment_config("nse_bonds")}')
Source code in stock_brokers/instruments/mapping/base.py
_field
¶
Read one raw column value, applying a named transform when the specification asks for one.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from the broker's instrument table. |
required |
specification
|
str | dict
|
Either a bare column name, or a dict with "column" and optionally "transform" keys. |
required |
Returns:
| Type | Description |
|---|---|
Any
|
The column value, transformed if requested. |
Source code in stock_brokers/instruments/mapping/base.py
_row_matches
¶
Check one equality rule against a raw row.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from the broker's instrument table. |
required |
match
|
dict
|
Mapping of raw column name to expected value, or to a list of acceptable values. |
required |
Returns:
| Type | Description |
|---|---|
bool
|
True when every column in the rule matches. |
Source code in stock_brokers/instruments/mapping/base.py
_uncategorised_config
¶
Pick the uncategorised segment configuration a row falls back into.
The per-exchange bucket is used when uncategorised_exchange resolves an exchange and the rules file configures that bucket; otherwise the unprefixed uncategorised entry is used.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
raw_row
|
dict
|
One raw row from the broker's instrument table. |
required |
Returns:
| Type | Description |
|---|---|
dict
|
The uncategorised segment configuration. |
Raises:
| Type | Description |
|---|---|
ValueError
|
If no uncategorised configuration exists, which validation should have made impossible. |
Source code in stock_brokers/instruments/mapping/base.py
read_raw_rows
¶
Read the broker's raw rows for one date.
Adapters override this where the fetch itself is part of the mapping: to impose a row order the classification depends on, or to bring in rows the plain query would miss.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
connection
|
Connection
|
An open SQLAlchemy connection. |
required |
mapping_date
|
date
|
The raw snapshot date to read. |
required |
Returns:
| Type | Description |
|---|---|
DataFrame
|
The raw rows for that date. |
Example usage
raw = self.adapter.read_raw_rows(self.connection, self.mapping_date)
Source code in stock_brokers/instruments/mapping/base.py
_write_results
¶
Write one run's rows into the mapped tables inside a single transaction.
Both row lists are sorted by instrument id before the insert so concurrent writers acquire locks in the same order, which is the standard fix for the multi-writer deadlock this design was observed hitting when adapters ran in parallel.
The seen dates widen rather than overwrite, so they do not depend on the order dates happen to be mapped in. Assigning the run's date to the last seen date directly looks equivalent while a backfill walks forward, and is wrong the moment any older date is mapped afterwards: it drags the last seen date backwards, and leaves the first seen date frozen at whichever date was written first rather than the earliest the instrument was actually seen.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
instrument_rows
|
dict
|
Mapping of instrument id to the unified.instruments row. |
required |
broker_rows
|
dict
|
Mapping of instrument id to the unified.broker_mappings row. |
required |
mapping_date
|
date
|
The mapping date the run covers. |
required |
Source code in stock_brokers/instruments/mapping/base.py
is_blank
¶
Check whether a raw value is absent or empty, in any of the forms the raw tables produce.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
value
|
str | float | None
|
One raw column value. |
required |
Returns:
| Type | Description |
|---|---|
bool
|
True when the value is None, an empty string, or a pandas missing value. |
Source code in stock_brokers/instruments/mapping/zerodha.py
normalize_index_name
¶
Reduce an index name to uppercase alphanumerics so that differently-spelled broker names collide.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
name
|
str
|
The raw index name. |
required |
Returns:
| Type | Description |
|---|---|
str
|
The name with every non-alphanumeric character removed and uppercased. |