1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
|
"""Main NVD API client."""
import os
from typing import Any, Dict, Optional, Type, TypeVar
import httpx
from pydantic import BaseModel
from .exceptions import (
AuthenticationError,
NetworkError,
NotFoundError,
RateLimitError,
ResponseError,
ServerError,
ValidationError,
)
from .rate_limiter import RateLimiter
T = TypeVar("T", bound=BaseModel)
class NVDClient:
"""Async client for the NVD API 2.0.
Example:
async with NVDClient(api_key="your-key") as client:
cve = await client.cve.get_cve("CVE-2021-44228")
"""
BASE_URL = "https://services.nvd.nist.gov/rest/json"
def __init__(
self,
api_key: Optional[str] = None,
timeout: float = 30.0,
max_retries: int = 3,
) -> None:
"""Initialize the NVD API client.
Args:
api_key: Optional API key for higher rate limits (50 req/30s vs 5 req/30s)
timeout: Request timeout in seconds
max_retries: Maximum number of retries for failed requests
"""
self.api_key = api_key or os.getenv("NVD_API_KEY")
self.timeout = timeout
self.max_retries = max_retries
self._client: Optional[httpx.AsyncClient] = None
self._rate_limiter = RateLimiter()
self._rate_limiter.configure(has_api_key=bool(self.api_key))
# Import endpoints here to avoid circular imports
from .endpoints.cpe import CPEEndpoint
from .endpoints.cpematch import CPEMatchEndpoint
from .endpoints.cve import CVEEndpoint
from .endpoints.cve_history import CVEHistoryEndpoint
from .endpoints.source import SourceEndpoint
self.cve = CVEEndpoint(self)
self.cpe = CPEEndpoint(self)
self.cpematch = CPEMatchEndpoint(self)
self.source = SourceEndpoint(self)
self.history = CVEHistoryEndpoint(self)
async def __aenter__(self) -> "NVDClient":
"""Async context manager entry."""
headers = {"User-Agent": "nvdb-py/0.1.0"}
if self.api_key:
headers["apiKey"] = self.api_key
self._client = httpx.AsyncClient(
base_url=self.BASE_URL,
headers=headers,
timeout=self.timeout,
http2=True,
)
return self
async def __aexit__(self, *args: Any) -> None:
"""Async context manager exit."""
if self._client:
await self._client.aclose()
async def request(
self,
method: str,
endpoint: str,
params: Optional[Dict[str, Any]] = None,
response_model: Optional[Type[T]] = None,
) -> T:
"""Make an API request with rate limiting and error handling.
Args:
method: HTTP method
endpoint: API endpoint path
params: Query parameters
response_model: Pydantic model for response validation
Returns:
Parsed response object
Raises:
Various NVDError subclasses based on error type
"""
if not self._client:
raise RuntimeError("Client not initialized. Use 'async with' context manager.")
# Clean up None values from params
if params:
params = {k: v for k, v in params.items() if v is not None}
retry_count = 0
last_error: Optional[Exception] = None
while retry_count < self.max_retries:
try:
# Wait for rate limiter
await self._rate_limiter.acquire()
# Make request
response = await self._client.request(
method=method,
url=endpoint,
params=params,
)
# Handle response
if response.status_code == 200:
try:
data = response.json()
if response_model:
return response_model.model_validate(data)
return data # type: ignore
except Exception as e:
raise ResponseError(f"Failed to parse response: {e}", response)
elif response.status_code == 400:
raise ValidationError(
f"Invalid request parameters: {response.text}", response
)
elif response.status_code == 403:
if "api key" in response.text.lower():
raise AuthenticationError(
"Invalid or missing API key", response
)
raise RateLimitError(
"Rate limit exceeded (403)", retry_after=30, response=response
)
elif response.status_code == 404:
# Provide helpful error messages for common mistakes
error_msg = f"Resource not found: {endpoint}"
if endpoint == "/cpes/2.0" and params:
if "cpeMatchString" in params:
error_msg = (
f"Invalid CPE match string: {params['cpeMatchString']}. "
"CPE match strings must use the format 'cpe:2.3:...'. "
"For keyword searches, use keywordSearch parameter instead. "
"Example: cpe:2.3:a:vendor:product:* or use --keyword for text search."
)
raise NotFoundError(error_msg, response)
elif response.status_code == 429:
retry_after = int(response.headers.get("Retry-After", 30))
raise RateLimitError(
"Rate limit exceeded (429)", retry_after=retry_after, response=response
)
elif response.status_code >= 500:
raise ServerError(
f"Server error ({response.status_code}): {response.text}",
response,
)
else:
raise ResponseError(
f"Unexpected status code {response.status_code}: {response.text}",
response,
)
except (RateLimitError, httpx.RequestError) as e:
last_error = e
retry_count += 1
if retry_count < self.max_retries:
# Exponential backoff
import asyncio
await asyncio.sleep(2 ** retry_count)
continue
except (
AuthenticationError,
ValidationError,
NotFoundError,
ServerError,
ResponseError,
):
raise
except Exception as e:
raise NetworkError(f"Network error: {e}")
# If we exhausted retries, raise the last error
if last_error:
raise last_error
raise NetworkError("Max retries exceeded")
async def close(self) -> None:
"""Close the HTTP client."""
if self._client:
await self._client.aclose()
|
