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1 change: 1 addition & 0 deletions .github/workflows/linters.yml
Original file line number Diff line number Diff line change
Expand Up @@ -29,6 +29,7 @@ jobs:
pip install .[all]
pip install .[tests]
pip install pylint ruff
pip install --upgrade pylint
- name: Ruff (lint)
run: ruff check --output-format=github .
- name: Ruff (format)
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3 changes: 2 additions & 1 deletion .pylintrc
Original file line number Diff line number Diff line change
@@ -1,4 +1,5 @@
[MAIN]
# pylint: disable=unrecognized-option

# Analyse import fallback blocks. This can be used to support both Python 2 and
# 3 compatible code, which means that the block might have code that exists
Expand Down Expand Up @@ -101,7 +102,7 @@ source-roots=

# When enabled, pylint would attempt to guess common misconfiguration and emit
# user-friendly hints instead of false-positive error messages.
suggestion-mode=yes
#suggestion-mode=yes

# Allow loading of arbitrary C extensions. Extensions are imported into the
# active Python interpreter and may run arbitrary code.
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82 changes: 82 additions & 0 deletions docs/user/motors/genericmotor.rst
Original file line number Diff line number Diff line change
@@ -1,5 +1,7 @@
# pylint: disable=unrecognized-option
.. _genericmotor:


GenericMotor Class Usage
========================

Expand Down Expand Up @@ -106,3 +108,83 @@ note that the user can still provide the parameters manually if needed.
The ``load_from_eng_file`` method is a very useful tool for simulating motors \
when the user does not have all the information required to build a ``SolidMotor`` yet.

The ``load_from_thrustcurve_api`` method
---------------------------------------

The ``GenericMotor`` class provides a convenience loader that downloads a temporary
`.eng` file from the ThrustCurve.org public API and builds a ``GenericMotor``
instance from it. This is useful when you know a motor designation (for example
``"M1670"``) but do not want to manually download and
save the `.eng` file.

.. note::

This method performs network requests to the ThrustCurve API. Use it only
when you have network access. For automated testing or reproducible runs,
prefer using local `.eng` files.
Signature
----------

``GenericMotor.load_from_thrustcurve_api(name: str, **kwargs) -> GenericMotor``

Parameters
----------
name : str
Motor name to search on ThrustCurve (example:
``"M1670"``).Only shorthand names are accepted (e.g. ``"M1670"``, not
``"Cesaroni M1670"``).
when multiple matches occur the first result returned by the API is used.
**kwargs :
Same optional arguments accepted by the :class:`GenericMotor` constructor
(e.g. ``dry_mass``, ``nozzle_radius``, ``interpolation_method``). Any
parameters provided here override values parsed from the downloaded file.

Returns
----------
GenericMotor
A new ``GenericMotor`` instance created from the .eng data downloaded from
ThrustCurve.

Raises
----------
ValueError
If the API search returns no motor, or if the download endpoint returns no
.eng file or empty/invalid data.
requests.exceptions.RequestException

Behavior notes
---------------
- The method first performs a search on ThrustCurve using the provided name.
If no results are returned a :class:`ValueError` is raised.
- If a motor is found the method requests the .eng file in RASP format, decodes
it and temporarily writes it to disk; a ``GenericMotor`` is then constructed
using the existing .eng file loader. The temporary file is removed even if an
error occurs.
- The function emits a non-fatal informational warning when a motor is found
(``warnings.warn(...)``). This follows the repository convention for
non-critical messages; callers can filter or suppress warnings as needed.

Example
---------------

.. jupyter-execute::

from rocketpy.motors import GenericMotor

# Build a motor by name (requires network access)
motor = GenericMotor.load_from_thrustcurve_api("M1670")

# Use the motor as usual
motor.info()

Testing advice
---------------
- ``pytest``'s ``caplog`` or ``capfd`` to assert on log/warning output.

Security & reliability
----------------
- The method makes outgoing HTTP requests and decodes base64-encoded content;
validate inputs in upstream code if you accept motor names from untrusted
sources.
- Network failures, API rate limits, or changes to the ThrustCurve API may
break loading; consider caching downloaded `.eng` files for production use.
120 changes: 119 additions & 1 deletion rocketpy/motors/motor.py
Original file line number Diff line number Diff line change
@@ -1,11 +1,14 @@
import base64
import re
import tempfile
import warnings
import xml.etree.ElementTree as ET
from abc import ABC, abstractmethod
from functools import cached_property
from os import path
from os import path, remove

import numpy as np
import requests

from ..mathutils.function import Function, funcify_method
from ..plots.motor_plots import _MotorPlots
Expand Down Expand Up @@ -1914,6 +1917,121 @@ def load_from_rse_file(
coordinate_system_orientation=coordinate_system_orientation,
)

@staticmethod
def call_thrustcurve_api(name: str):
"""
Download a .eng file from the ThrustCurve API
based on the given motor name.

Parameters
----------
name : str
The motor name according to the API (e.g., "Cesaroni_M1670" or "M1670").
Both manufacturer-prefixed and shorthand names are commonly used; if multiple
motors match the search, the first result is used.

Returns
-------
data_base64 : String
The .eng file of the motor in base64

Raises
------
ValueError
If no motor is found or if the downloaded .eng data is missing.
requests.exceptions.RequestException
If a network or HTTP error occurs during the API call.
"""
base_url = "https://www.thrustcurve.org/api/v1"

# Step 1. Search motor
response = requests.get(f"{base_url}/search.json", params={"commonName": name})
response.raise_for_status()
data = response.json()

if not data.get("results"):
raise ValueError(
f"No motor found for name '{name}'. "
"Please verify the motor name format (e.g., 'Cesaroni_M1670' or 'M1670') and try again."
)

motor_info = data["results"][0]
motor_id = motor_info.get("motorId")
designation = motor_info.get("designation", "").replace("/", "-")
manufacturer = motor_info.get("manufacturer", "")
warnings.warn(f"Motor found: {designation} ({manufacturer})", UserWarning)

# Step 2. Download the .eng file
dl_response = requests.get(
f"{base_url}/download.json",
params={"motorIds": motor_id, "format": "RASP", "data": "file"},
)
dl_response.raise_for_status()
dl_data = dl_response.json()

if not dl_data.get("results"):
raise ValueError(
f"No .eng file found for motor '{name}' in the ThrustCurve API."
)

data_base64 = dl_data["results"][0].get("data")
if not data_base64:
raise ValueError(
f"Downloaded .eng data for motor '{name}' is empty or invalid."
)
return data_base64

@staticmethod
def load_from_thrustcurve_api(name: str, **kwargs):
"""
Creates a Motor instance by downloading a .eng file from the ThrustCurve API
based on the given motor name.

Parameters
----------
name : str
The motor name according to the API (e.g., "Cesaroni_M1670" or "M1670").
Both manufacturer-prefixed and shorthand names are commonly used; if multiple
motors match the search, the first result is used.
**kwargs :
Additional arguments passed to the Motor constructor or loader, such as
dry_mass, nozzle_radius, etc.

Returns
-------
instance : GenericMotor
A new GenericMotor instance initialized using the downloaded .eng file.

Raises
------
ValueError
If no motor is found or if the downloaded .eng data is missing.
requests.exceptions.RequestException
If a network or HTTP error occurs during the API call.
"""

data_base64 = GenericMotor.call_thrustcurve_api(name)
data_bytes = base64.b64decode(data_base64)

# Step 3. Create the motor from the .eng file
tmp_path = None
try:
# create a temporary file that persists until we explicitly remove it
with tempfile.NamedTemporaryFile(suffix=".eng", delete=False) as tmp_file:
tmp_file.write(data_bytes)
tmp_file.flush()
tmp_path = tmp_file.name

return GenericMotor.load_from_eng_file(tmp_path, **kwargs)
finally:
# Ensuring the temporary file is removed
if tmp_path and path.exists(tmp_path):
try:
remove(tmp_path)
except OSError:
# If cleanup fails, don't raise: we don't want to mask prior exceptions.
pass

def all_info(self):
"""Prints out all data and graphs available about the Motor."""
# Print motor details
Expand Down
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