fmp-py-sdk

fmp-py-sdk is the Python distribution for the Rust-backed fmp package, a typed client for the Financial Modeling Prep (FMP) data API.

The client exposes every libfmp endpoint method: 271 methods grouped into 30 domain namespaces on FmpClient. Each namespace is generated from a registry that is validated against the real libfmp signatures, so the Python surface cannot drift from the Rust one.

python -m pip install fmp-py-sdk

from fmp import FmpClient

client = FmpClient()
rows = client.quote.short("AAPL")
print(rows[0].symbol, rows[0].price)

FmpClient() reads the FMP_API_KEY environment variable when token is omitted (unset, empty, or whitespace-only counts as absent); an explicit token=... always wins, and auth_mode="none" ignores the variable. With neither a token nor the variable, the default host raises FmpConfigError naming FMP_API_KEY, while a custom base_url selects no auth.

FmpClient is synchronous: each call releases the Python GIL while the async Rust transport waits, so threads keep running. A Python async facade is not part of this release.

Requirements

• CPython 3.10 or newer (abi3-py310: one wheel per platform covers every supported interpreter).
• Rust is only needed to build from source; a built wheel is self-contained.
• Do not install the unrelated PyPI distribution named fmp in the same environment: it also provides an fmp import package, and the two collide.

Namespaces

Endpoints live under one attribute per domain, and nested domains such as statements group their sub-namespaces. Required arguments are positional, optional ones are keyword-only, and every name is snake_case: the FMP wire casing (sicCode, linkXlsx) never reaches Python.

from fmp import FmpClient

client = FmpClient()

quotes = client.quote.short("AAPL")
income = client.statements.income.statement("AAPL", period="annual", limit=5)
valuation = client.dcf.custom(
    "AAPL", beta=1.2, tax_rate=0.21, long_term_growth_rate=4.0
)

statements nests as_reported, balance, cash_flow, growth, income, metrics, ratios, reports, segmentation, and summaries.

Responses

• Typed rows: most methods return list[Model], where each model is a generated, immutable, picklable class living in the domain package (for example fmp.quote.QuoteShort or fmp.statements.income.IncomeStatement). Dates and naive timestamps are datetime.date and datetime.datetime; RFC 3339 timestamps (for example TipRanksRatingSearchResult.date) stay str with the exact wire text. Shared Rust response types map to one shared Python class rather than a copy per endpoint.
• Models behave like frozen value objects: see Working with models.
• Numeric strings (for example CompanyProfile.full_time_employees) stay str with the exact wire text; wrap them with decimal.Decimal(...) for arithmetic.
• Unix timestamps are int in the unit the provider sends: Quote.timestamp is seconds, while AftermarketTrade.timestamp and AftermarketQuote.timestamp are milliseconds.
• Naive datetime.datetime values carry no timezone because the provider does not document one; the binding does not attach or assume UTC.
• Dynamic rows: endpoints whose documented shape is open-ended return list[dict[str, Any]] with the raw provider keys, for example client.sec_filings.search_industry_classifications(symbol="AAPL"). A dynamic field inside a typed model (such as FinancialReportJson.sections) is exposed as Any. A JSON-number field (for example CotReport.pct_of_open_interest_all) is int | float: an int when the provider sent an integer literal (exact at any size), a float otherwise.
• Binary bodies: client.statements.reports.xlsx("AAPL", 2022, "FY") returns a single fmp.BinaryPayload instead of a list. data is the body as bytes, alongside content_type, content_disposition, and byte_len.

Working with models

from fmp.quote import QuoteShort

row = QuoteShort(symbol="AAPL", price=232.8, change=1.2, volume=41_000_000.0)
row == QuoteShort(**row.to_dict())  # True: equality compares every field
row.to_dict()                       # {"symbol": "AAPL", "price": 232.8, ...}
repr(row)                           # "QuoteShort(symbol='AAPL', price=232.8, ...)"

match row:
    case QuoteShort(symbol, price):  # positional patterns follow __match_args__
        print(symbol, price)

• Constructors are keyword-only. Every model can be built by hand (for tests or fixtures) with the attribute names as keywords.
• == compares by value. Because of that, models are unhashable (__hash__ is None, as for any Python class that defines __eq__): they cannot be set members or dict keys. Key a dict by a field instead, for example {row.symbol: row for row in rows}.
• repr() lists every attribute in constructor order, and __match_args__ holds the same names for positional case patterns.
• to_dict() returns a plain dict keyed by attribute name; nested models become dicts and lists of models become lists of dicts. JSON-number fields are int | float, dynamic fields are the decoded JSON.
• Pickling and copy.copy rebuild the row by keyword through __getnewargs_ex__.
• Secret fields are not attributes: they are left out of repr(), __match_args__, and to_dict() (see Secret URLs).

Validation and errors

Arguments are validated locally before any request: an empty ticker, a malformed date, or a non-finite float raises FmpValidationError whose message starts with the argument name, and nothing is sent. The exception hierarchy lives in fmp.errors (every class is also exported from the package root):

from fmp import FmpClient
from fmp.errors import FmpStatusError

client = FmpClient()
try:
    client.quote.short("AAPL")
except FmpStatusError as error:
    print(error.status, error.endpoint, error.body)

Bodies attached to errors are redacted before they reach Python: an echoed apikey query value shows as [REDACTED].

Custom router or proxy

import os

from fmp import FmpClient

client = FmpClient(
    base_url=os.environ["FMP_PROXY_BASE_URL"],
    path_prefix="router/stable",
    auth_mode="custom_header",
    auth_name="X-Proxy-Token",
    auth_prefix="Bearer ",
    token=os.environ["FMP_PROXY_TOKEN"],
    headers={"X-Tenant": os.environ["FMP_TENANT"]},
)
rows = client.quote.short("AAPL")

Available auth modes are none, fmp_header, fmp_query, bearer, custom_header, and custom_query. auth_mode="none" supports credential-free local or trusted routers. Redirect following is either disabled or same-origin only.

Typing

The package ships a py.typed marker, and every native module has a .pyi stub generated by pyo3-stub-gen from the Rust signatures, so pyright and mypy see the exact method names, keyword-only arguments, and return types. Closed string vocabularies are typing.Literal types: period arguments ("Q1".."FY", "annual", "quarter"), technical-indicator timeframe, revenue-segmentation structure, FmpClient(auth_mode=...), and model fields such as IncomeStatement.period or the "Y"/"N" flags. The stubs list the canonical spellings; at runtime period, timeframe, and structure stay case-insensitive and accept the documented aliases (for example "quarterly"), which a type checker rejects, while auth_mode must match exactly. Open vocabularies (form types, economic indicator names) stay str. FmpClient(headers=...) takes any Mapping[str, str].

The test suite runs python -m mypy.stubtest fmp and mypy on tests/typecheck_contract.py whenever mypy is installed in the test environment, so a stub that drifts from the built extension fails pytest. The public modules follow a conventional HTTP SDK layout: FmpClient lives in fmp.client, the exception hierarchy in fmp.errors, and the models and namespace classes in the domain packages such as fmp.quote and fmp.statements.income. Transport, configuration, and runtime internals are intentionally not exposed as Python modules.

Secret URLs

FinancialReportDate.link_json / link_xlsx (the fmp.statements.reports model listing available financial reports) are download links that embed your API key. The Python model treats them the way FmpClient treats danger_allow_insecure_authentication: the unsafe path exists, but it is conspicuous.

• The links are not attributes. Read one with row.expose_secret_url_json() or row.expose_secret_url_xlsx() and treat the value as a credential.
• repr(row) and str(row) print link_json=[REDACTED URL], so a stray print or log line never leaks the key.
• For local debugging only, fmp.set_reveal_secret_urls(True) reveals the URLs in repr() process-wide (fmp.reveal_secret_urls() reads the flag back). Setting FMP_REVEAL_SECRET_URLS=1 (also true / yes, case-insensitive) before the first use turns it on at start-up.
• Pickles of the model contain the real URLs: pickle.dumps must round-trip the value, so store them as carefully as the key itself.
• to_dict() and __match_args__ leave the links out; == still compares them.

Regenerating the response models

The pyo3 response models under crates/fmp-py/src/models/ are generated from the libfmp response structs by the gen_models binary in the sibling crates/fmp-py-gen crate. Run it from the repository root:

cargo run -p fmp-py-gen --bin gen_models

The generator only depends on syn, not on fmp-py, so it still builds and runs when fmp-py fails to compile against a changed libfmp. Regeneration must be idempotent: git status crates/fmp-py/src/models is clean after a second run.

Validating the endpoint registry

The Python namespaces are described by one TOML file per domain under crates/fmp-py-gen/registry/ (quote.toml for client.quote). Each entry names the Python method, the libfmp Client method, its query type, the constructor arguments and optional with_* setters with their arg kinds, and the generated response model. Validate the registry against the real libfmp signatures and the generated models from the repository root:

cargo run -p fmp-py-gen --bin registry_check

The check parses crates/libfmp/src/endpoints/** with syn, so an unknown method, a mismatched query type, an unknown arg kind, a setter that does not exist, or a missing model file fails with the file and entry named. Query types emitted by macro_rules! are recovered by expanding the macro; the report says whether each entry was verified directly, through a macro, or trusted because its constructor could not be seen, and ends with the total (registry ok: 271 verified, 0 trusted). Pass a directory argument to check a different registry tree.

Regenerating the endpoint namespaces

The namespace classes under crates/fmp-py/src/namespaces/ (QuoteNamespace for client.quote) are generated from the same registry by the gen_namespaces binary, which validates the registry first and emits nothing on any error. Run it from the repository root:

cargo run -p fmp-py-gen --bin gen_namespaces

Flat domains become namespaces/<domain>.rs; a nested path such as statements.income becomes namespaces/statements/mod.rs (the parent with a getter per sub-namespace) plus namespaces/statements/income.rs. Required arguments are positional, optional ones keyword-only, and an argument named after a Python keyword (from) is spelled with a trailing underscore (from_) on the Python side while the libfmp setter keeps its name. Entries marked binary = true (the endpoints whose libfmp method returns BinaryResponse, such as the XLSX financial report download) return a single BinaryPayload instead of a list of models; entries marked response = "dynamic" return list[dict[str, Any]]. BinaryPayload is hand-written in src/binary.rs and exported from the package root as fmp.BinaryPayload.

The same run emits the wiring that binds the generated code into the extension, so adding a domain never edits lib.rs or client.rs:

The hand-written src/facade.rs keeps only the top-level fmp surface.

Regenerating the Go SDK

The Go module at sdk/go (ADR 0030) is generated from the same registry, the wire contract read from crates/libfmp/src/endpoints/**, and the response structs, by the gen_go binary. The three generators, from the repository root:

cargo run -p fmp-py-gen --bin gen_models      # fmp-py response models
cargo run -p fmp-py-gen --bin gen_namespaces  # fmp-py endpoint namespaces
cargo run -p fmp-py-gen --bin gen_go          # sdk/go, every generated domain

gen_go --domain <name> (repeatable) generates the named domains; with no argument it regenerates every domain that already carries the generated header; --all regenerates all 30. It writes sdk/go/<domain>_models.go, sdk/go/<domain>.go, and the shared queries.go and namespaces.go, all through gofmt, so a second run leaves git status clean; the scripts/check_go_sdk.sh gate proves it. A Rust type or argument kind the generator does not know fails the run naming the struct and field (or the query.go helper to add); nothing is emitted in that case.

Regenerating the stubs and public packages

The .pyi stubs under python/fmp/_native/ and the public python/fmp/<path>/__init__.py packages are written by pyo3-stub-gen through the stub_gen binary, from the repository root:

cargo run -p fmp-py --bin stub_gen

stub_gen post-processes each __init__.pyi (absolute imports, fully qualified module references so a method named like a module cannot shadow it, the typeshed __hash__: ClassVar[None] spelling, no # ruff: noqa header, ruff format --isolated --line-length 88 in .py mode) so a run on an unchanged tree leaves git status clean. It needs ruff at the version pinned in this crate's .pre-commit-config.yaml and as RUFF_VERSION in src/bin/stub_gen.rs (currently 0.15.12, the two must agree): either that exact ruff on PATH or uvx, which fetches it. Run it after gen_models or gen_namespaces, and commit the result.

This project is available under the MIT License.