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feat: updated detector using Ela fft and meta
0b8f50d
import os
import asyncio
import logging
from io import BytesIO
from fastapi import HTTPException, UploadFile, status, Depends
from fastapi.security import HTTPBearer, HTTPAuthorizationCredentials
from .inferencer import classify_text
from .preprocess import parse_docx, parse_pdf, parse_txt
import spacy
security = HTTPBearer()
nlp = spacy.load("en_core_web_sm")
# Verify Bearer token from Authorization header
async def verify_token(credentials: HTTPAuthorizationCredentials = Depends(security)):
token = credentials.credentials
expected_token = os.getenv("MY_SECRET_TOKEN")
if token != expected_token:
raise HTTPException(
status_code=status.HTTP_403_FORBIDDEN,
detail="Invalid or expired token"
)
return token
# Classify plain text input
async def handle_text_analysis(text: str):
text = text.strip()
if not text or len(text.split()) < 10:
raise HTTPException(status_code=400, detail="Text must contain at least 10 words")
if len(text) > 10000:
raise HTTPException(status_code=413, detail="Text must be less than 10,000 characters")
label, perplexity, ai_likelihood = await asyncio.to_thread(classify_text, text)
return {
"result": label,
"perplexity": round(perplexity, 2),
"ai_likelihood": ai_likelihood
}
# Extract text from uploaded files (.docx, .pdf, .txt)
async def extract_file_contents(file: UploadFile) -> str:
content = await file.read()
file_stream = BytesIO(content)
if file.content_type == "application/vnd.openxmlformats-officedocument.wordprocessingml.document":
return parse_docx(file_stream)
elif file.content_type == "application/pdf":
return parse_pdf(file_stream)
elif file.content_type == "text/plain":
return parse_txt(file_stream)
else:
raise HTTPException(
status_code=415,
detail="Invalid file type. Only .docx, .pdf and .txt are allowed."
)
# Classify text from uploaded file
async def handle_file_upload(file: UploadFile):
try:
file_contents = await extract_file_contents(file)
if len(file_contents) > 10000:
raise HTTPException(status_code=413, detail="Text must be less than 10,000 characters")
cleaned_text = file_contents.replace("\n", " ").replace("\t", " ").strip()
if not cleaned_text:
raise HTTPException(status_code=404, detail="The file is empty or only contains whitespace.")
label, perplexity, ai_likelihood = await asyncio.to_thread(classify_text, cleaned_text)
return {
"content": file_contents,
"result": label,
"perplexity": round(perplexity, 2),
"ai_likelihood": ai_likelihood
}
except Exception as e:
logging.error(f"Error processing file: {e}")
raise HTTPException(status_code=500, detail="Error processing the file")
async def handle_sentence_level_analysis(text: str):
text = text.strip()
if not text.endswith("."):
text += "."
if len(text) > 10000:
raise HTTPException(status_code=413, detail="Text must be less than 10,000 characters")
doc = nlp(text)
sentences = [sent.text.strip() for sent in doc.sents]
results = []
for sentence in sentences:
if not sentence:
continue
label, perplexity, ai_likelihood = await asyncio.to_thread(classify_text, sentence)
results.append({
"sentence": sentence,
"label": label,
"perplexity": round(perplexity, 2),
"ai_likelihood": ai_likelihood
})
return {"analysis": results}# Analyze each sentence from uploaded file
async def handle_file_sentence(file: UploadFile):
try:
file_contents = await extract_file_contents(file)
if len(file_contents) > 10000:
raise HTTPException(status_code=413, detail="Text must be less than 10,000 characters")
cleaned_text = file_contents.replace("\n", " ").replace("\t", " ").strip()
if not cleaned_text:
raise HTTPException(status_code=404, detail="The file is empty or only contains whitespace.")
result = await handle_sentence_level_analysis(cleaned_text)
return {
"content": file_contents,
**result
}
except Exception as e:
logging.error(f"Error processing file: {e}")
raise HTTPException(status_code=500, detail="Error processing the file")
def classify(text: str):
return classify_text(text)