from mcp.server.fastmcp import FastMCP
from faker import Faker
from datetime import datetime, timedelta
import random
from pydantic import BaseModel
from typing import List, Literal, Optional
class FieldSpec(BaseModel):
name: str
type: Literal["string", "enum", "integer", "date", "filler"]
length: int
values: Optional[list[str]] = None
format: Optional[str] = "%Y%m%d"
min: Optional[int] = 0
max: Optional[int] = 9999
fake = Faker()
mcp = FastMCP("SampleDataMCP")
def pad(value, length):
return str(value)[:length].ljust(length)
def generate_field(field):
ftype = field.type
length = field.length
if ftype == "string":
return pad(fake.name(), length)
elif ftype == "enum":
return pad(random.choice(field.values), length)
elif ftype == "integer":
min_val = field.min
max_val = field.max
return pad(str(random.randint(min_val, max_val)), length)
elif ftype == "date":
fmt = field.format
random_date = datetime.today() - timedelta(days=random.randint(0, 3650))
return pad(random_date.strftime(fmt), length)
elif ftype == "filler":
return " " * length
else:
return pad("?", length)
def generate_test_data(fields, num_records):
lines = []
for _ in range(num_records):
line = "".join(generate_field(field) for field in fields)
lines.append(line)
return "\n".join(lines)
@mcp.tool()
def generate_test_data_tool(fields: List[FieldSpec], num_records: int) -> str:
"""Generate fixed-length test data based on a field specification"""
return generate_test_data(fields, num_records)
if __name__ == "__main__":
mcp.run('stdio')
