from fastapi import FastAPI, File, HTTPException, UploadFile from pydantic import BaseModel, Field from transformers import AutoTokenizer, AutoModelForSeq2SeqLM from cachetools import TTLCache from PIL import Image from pypdf import PdfReader from docx import Document import fitz import hashlib import io import json import os import re import torch import pytesseract from urllib import request as urllib_request from urllib.error import URLError, HTTPError app = FastAPI(title="Local AI Service") MODEL_NAME = "sshleifer/distilbart-cnn-12-6" MAX_INPUT_CHARS = 20000 MAX_CONTEXT_CHARS = 2200 MAX_EXTRACT_FILE_BYTES = 8 * 1024 * 1024 OCR_LANGUAGES = "eng" IMAGE_EXTENSIONS = {".png", ".jpg", ".jpeg", ".webp"} OLLAMA_BASE_URL = os.getenv("OLLAMA_BASE_URL", "http://127.0.0.1:11434").rstrip("/") OLLAMA_MODEL = os.getenv("OLLAMA_MODEL", "") SKIP_MODEL_LOAD = os.getenv("AI_SERVICE_SKIP_MODEL_LOAD", "") == "1" EAGER_MODEL_LOAD = os.getenv("AI_SERVICE_EAGER_MODEL_LOAD", "") == "1" tokenizer = None model = None device = torch.device("cpu") GPU_AVAILABLE = False GPU_NAME = None MODEL_LOAD_ERROR = "Model loading is disabled by AI_SERVICE_SKIP_MODEL_LOAD." if SKIP_MODEL_LOAD else None MODEL_LOADED = False MODEL_DISABLED = SKIP_MODEL_LOAD def _load_runtime(): tokenizer = AutoTokenizer.from_pretrained(MODEL_NAME) model = AutoModelForSeq2SeqLM.from_pretrained(MODEL_NAME) model.eval() has_cuda = torch.cuda.is_available() device = torch.device("cuda" if has_cuda else "cpu") model.to(device) gpu_name = torch.cuda.get_device_name(0) if has_cuda else None return tokenizer, model, device, has_cuda, gpu_name def _ensure_runtime_loaded(): global tokenizer, model, device, GPU_AVAILABLE, GPU_NAME, MODEL_LOAD_ERROR, MODEL_LOADED if MODEL_DISABLED: MODEL_LOAD_ERROR = "Model loading is disabled by AI_SERVICE_SKIP_MODEL_LOAD." return False if MODEL_LOADED and tokenizer is not None and model is not None: return True try: tokenizer, model, device, GPU_AVAILABLE, GPU_NAME = _load_runtime() MODEL_LOAD_ERROR = None MODEL_LOADED = True return True except Exception as exc: tokenizer, model = None, None device = torch.device("cpu") GPU_AVAILABLE = False GPU_NAME = None MODEL_LOADED = False MODEL_LOAD_ERROR = str(exc) return False if EAGER_MODEL_LOAD and not SKIP_MODEL_LOAD: _ensure_runtime_loaded() cache = TTLCache(maxsize=1024, ttl=60 * 60) class SummarizeRequest(BaseModel): text: str = Field(min_length=1, max_length=MAX_INPUT_CHARS) max_length: int = Field(default=160, ge=24, le=256) min_length: int = Field(default=45, ge=8, le=180) top_skills: int = Field(default=8, ge=3, le=12) class RewriteRequest(BaseModel): instruction: str = Field(min_length=1, max_length=6000) text: str = Field(min_length=1, max_length=MAX_INPUT_CHARS) max_length: int = Field(default=220, ge=24, le=256) min_length: int = Field(default=80, ge=8, le=180) class CvNormalizeRequest(BaseModel): text: str = Field(min_length=1, max_length=50000) class CvClassifyBlockRequest(BaseModel): block: str = Field(min_length=1, max_length=6000) def _key(text: str, max_length: int, min_length: int, top_skills: int) -> str: h = hashlib.sha256(text.encode("utf-8")).hexdigest() return f"{h}:{max_length}:{min_length}:{top_skills}" def _ollama_json(path: str): req = urllib_request.Request(f"{OLLAMA_BASE_URL}{path}", method="GET") with urllib_request.urlopen(req, timeout=5) as response: return json.loads(response.read().decode("utf-8")) def _ollama_status(): configured = bool(OLLAMA_MODEL) if not configured: return { "ollama_configured": False, "ollama_reachable": False, "ollama_model": None, "ollama_model_available": False, "ollama_version": None, "ollama_installed_models": [], "ollama_loaded_models": [], "ollama_loaded_count": 0, } try: tags_body = _ollama_json("/api/tags") version_body = _ollama_json("/api/version") try: ps_body = _ollama_json("/api/ps") except Exception: ps_body = {"models": []} except Exception: return { "ollama_configured": True, "ollama_reachable": False, "ollama_model": OLLAMA_MODEL, "ollama_model_available": False, "ollama_version": None, "ollama_installed_models": [], "ollama_loaded_models": [], "ollama_loaded_count": 0, } models = tags_body.get("models") or [] names = sorted({item.get("name") for item in models if isinstance(item, dict) and item.get("name")}) loaded_models = sorted({item.get("name") for item in (ps_body.get("models") or []) if isinstance(item, dict) and item.get("name")}) return { "ollama_configured": True, "ollama_reachable": True, "ollama_model": OLLAMA_MODEL, "ollama_model_available": OLLAMA_MODEL in names, "ollama_version": version_body.get("version"), "ollama_installed_models": names, "ollama_loaded_models": loaded_models, "ollama_loaded_count": len(loaded_models), } @app.get("/health") async def health(): return { "ok": True, "model": MODEL_NAME, "device": str(device), "gpu_available": GPU_AVAILABLE, "gpu_name": GPU_NAME, "ocr_available": True, "ocr_languages": OCR_LANGUAGES, "model_loaded": MODEL_LOADED, "model_disabled": MODEL_DISABLED, "summarize_available": MODEL_LOADED and not MODEL_DISABLED, "model_load_error": MODEL_LOAD_ERROR, **_ollama_status(), } _TECH = [ "python", "c#", "dotnet", ".net", "java", "javascript", "typescript", "react", "node", "sql", "postgres", "postgresql", "mysql", "sqlite", "mongodb", "redis", "aws", "azure", "gcp", "docker", "kubernetes", "terraform", "linux", "git", "ci/cd", "graphql", "rest", ] _SOFT = [ "communication", "collaboration", "teamwork", "problem solving", "leadership", "mentoring", "ownership", "initiative", "adaptability", "stakeholder management", "detail oriented", ] _TECH_PRIORITY = [ "python", "c#", ".net", "dotnet", "typescript", "javascript", "react", "node", "sql", "postgresql", "postgres", "mysql", "sqlite", "docker", "kubernetes", "aws", "azure", "gcp", "terraform", "graphql", "rest", "git", ] _MUST_HAVE_HINTS = [ "must have", "required", "requirements", "you have", "you bring", "essential", "we are looking for", ] _NICE_TO_HAVE_HINTS = [ "nice to have", "bonus", "preferred", "advantageous", "extra plus", ] _SCREENING_HINTS = [ "experience with", "hands-on", "demonstrated", "proven", "track record", "delivered", ] def _rank_tech_skills(skills): ordered = [] seen = set() for preferred in _TECH_PRIORITY: for skill in skills: if skill == preferred and skill not in seen: ordered.append(skill) seen.add(skill) for skill in skills: if skill not in seen: ordered.append(skill) seen.add(skill) return ordered def _strip_html(text: str) -> str: text = re.sub(r"<\s*br\s*/?>", "\n", text, flags=re.IGNORECASE) text = re.sub(r"", "\n", text, flags=re.IGNORECASE) text = re.sub(r"<[^>]+>", " ", text) return re.sub(r"\n{3,}", "\n\n", text).strip() def _extract_bullets(lines, max_items=8): out = [] for ln in lines: s = ln.strip() if not s: continue if re.match(r"^([-*]|\u2022)\s+", s): s = re.sub(r"^([-*]|\u2022)\s+", "", s).strip() if 3 <= len(s) <= 220: out.append(s) if len(out) >= max_items: break return out def _top_keywords(text: str, limit=6): words = re.findall(r"[a-zA-Z][a-zA-Z+#./-]{2,}", text.lower()) stop = { "with", "from", "that", "this", "will", "have", "your", "their", "about", "role", "team", "work", "experience", "skills", "requirements", "responsibilities", "company", "using", "ability", "years", "looking", "candidate", "position", "working", "across", "strong", "building", "support", } counts = {} for word in words: if word in stop or word in _TECH or word in _SOFT: continue counts[word] = counts.get(word, 0) + 1 ordered = sorted(counts.items(), key=lambda item: (-item[1], item[0])) return [word for word, _ in ordered[:limit]] def _first_matching_sentences(text: str, hints, limit=3): sentences = re.split(r"(?<=[.!?])\s+", text) found = [] for sentence in sentences: low = sentence.lower() if any(hint in low for hint in hints): cleaned = sentence.strip() if 20 <= len(cleaned) <= 220: found.append(cleaned) if len(found) >= limit: break return found def _trim_line(text: str, max_len: int = 140) -> str: text = re.sub(r"\s+", " ", text).strip(" -•\t") if len(text) <= max_len: return text return text[: max_len - 1].rstrip() + "…" def _role_focused_excerpt(text: str) -> dict: cleaned = _strip_html(text) lines = [ln.strip() for ln in cleaned.splitlines()] headings = { "responsibilities": ["responsibilities", "what you will do", "what you'll do", "the role", "your role", "you will"], "requirements": ["requirements", "what we are looking for", "what we're looking for", "skills", "experience", "must have"], "nice": ["nice to have", "bonus", "preferred"], } def match_heading(s: str): sl = s.lower().strip(":-\x7f ") for key, words in headings.items(): for word in words: if sl == word or sl.startswith(word + " "): return key return None section = None resp_lines = [] req_lines = [] nice_lines = [] for ln in lines: if not ln: continue heading = match_heading(ln) if heading: section = heading continue if section == "responsibilities": resp_lines.append(ln) elif section == "requirements": req_lines.append(ln) elif section == "nice": nice_lines.append(ln) responsibilities = _extract_bullets(resp_lines, max_items=7) requirements = _extract_bullets(req_lines, max_items=7) nice = _extract_bullets(nice_lines, max_items=5) tech_found = [] soft_found = [] low = cleaned.lower() for t in _TECH: if t in low: tech_found.append(t) for s in _SOFT: if s in low: soft_found.append(s) if not responsibilities and not requirements: any_bullets = _extract_bullets(lines, max_items=10) responsibilities = any_bullets[:6] requirements = any_bullets[6:10] if not requirements: requirements = [_trim_line(x) for x in _first_matching_sentences(cleaned, _MUST_HAVE_HINTS, limit=4)] if not nice: nice = [_trim_line(x) for x in _first_matching_sentences(cleaned, _NICE_TO_HAVE_HINTS, limit=3)] focused_parts = [] if responsibilities: focused_parts.append("Responsibilities:\n- " + "\n- ".join(responsibilities)) if requirements: focused_parts.append("Requirements:\n- " + "\n- ".join(requirements)) if nice: focused_parts.append("Nice to have:\n- " + "\n- ".join(nice)) focused_parts.append("Context:\n" + cleaned[:MAX_CONTEXT_CHARS]) screen_focus = [] for item in requirements[:4]: if any(hint in item.lower() for hint in _SCREENING_HINTS) or len(screen_focus) < 2: screen_focus.append(_trim_line(item)) if not screen_focus: screen_focus = [_trim_line(x) for x in _first_matching_sentences(cleaned, _SCREENING_HINTS, limit=3)] return { "cleaned": cleaned, "focused_input": "\n\n".join(focused_parts), "responsibilities": responsibilities, "requirements": requirements, "nice": nice, "tech": tech_found, "soft": soft_found, "keywords": _top_keywords(cleaned), "screen_focus": screen_focus[:3], } def _model_summarize(text: str, max_length: int, min_length: int) -> str: if not _ensure_runtime_loaded() or tokenizer is None or model is None: raise HTTPException(status_code=503, detail=MODEL_LOAD_ERROR or "Summarizer model is not loaded.") inputs = tokenizer(text, return_tensors="pt", truncation=True, max_length=1024) input_ids = inputs.input_ids.to(device) attention_mask = inputs.attention_mask.to(device) if hasattr(inputs, "attention_mask") else None with torch.no_grad(): outputs = model.generate( input_ids, attention_mask=attention_mask, max_length=max_length, min_length=min_length, num_beams=3, length_penalty=1.0, no_repeat_ngram_size=3, early_stopping=True, ) return tokenizer.decode(outputs[0], skip_special_tokens=True).strip() def _ollama_generate_json(prompt: str): if not OLLAMA_MODEL: raise HTTPException(status_code=503, detail="OLLAMA_MODEL is not configured.") payload = json.dumps({ "model": OLLAMA_MODEL, "prompt": prompt, "stream": False, "format": "json", "options": {"temperature": 0.1} }).encode("utf-8") req = urllib_request.Request( f"{OLLAMA_BASE_URL}/api/generate", data=payload, headers={"Content-Type": "application/json"}, method="POST", ) try: with urllib_request.urlopen(req, timeout=120) as response: body = json.loads(response.read().decode("utf-8")) except HTTPError as ex: raise HTTPException(status_code=502, detail=f"Ollama request failed with {ex.code}.") except URLError as ex: raise HTTPException(status_code=503, detail=f"Ollama is unreachable: {ex.reason}.") raw = (body.get("response") or "").strip() if not raw: raise HTTPException(status_code=502, detail="Ollama returned an empty response.") try: return json.loads(raw) except json.JSONDecodeError: start = raw.find("{") end = raw.rfind("}") if start >= 0 and end > start: return json.loads(raw[start:end + 1]) raise HTTPException(status_code=502, detail="Ollama did not return valid JSON.") def _ollama_generate_text(prompt: str) -> str: if not OLLAMA_MODEL: raise HTTPException(status_code=503, detail="OLLAMA_MODEL is not configured.") payload = json.dumps({ "model": OLLAMA_MODEL, "prompt": prompt, "stream": False, "options": {"temperature": 0.2} }).encode("utf-8") req = urllib_request.Request( f"{OLLAMA_BASE_URL}/api/generate", data=payload, headers={"Content-Type": "application/json"}, method="POST", ) try: with urllib_request.urlopen(req, timeout=180) as response: body = json.loads(response.read().decode("utf-8")) except HTTPError as ex: raise HTTPException(status_code=502, detail=f"Ollama request failed with {ex.code}.") except URLError as ex: raise HTTPException(status_code=503, detail=f"Ollama is unreachable: {ex.reason}.") raw = (body.get("response") or "").strip() if not raw: raise HTTPException(status_code=502, detail="Ollama returned an empty rewrite.") return raw @app.post("/cv/normalize") async def normalize_cv(req: CvNormalizeRequest): prompt = f""" You normalize messy CV text into parser-friendly master-CV text. Return ONLY valid JSON with this exact shape: {{ "confidence": 0.0, "reason": "short reason", "normalized_text": "string" }} Rules for normalized_text: - Preserve facts only. Do not invent. - Use markdown section headings exactly like these when data exists: # Contact # Professional Summary # Work Experience # Education # Skills # Languages # Interests - Under # Contact, put one plain value per line, no labels unless unavoidable: Full name line email line phone line website line location line - Under # Professional Summary, write 1-3 plain sentences or bullet lines. - Preserve explicitly mentioned technologies, tools, and methods as skills when they appear in the source. - Never output helper words like "line", "value", "field", or "item". - Under # Work Experience, for each job use this exact shape: Job title only Company, Location 2019 - Present - bullet - bullet - Under # Education, for each entry use this exact shape: Qualification line Institution, Location line 2016 - 2019 line - detail - Under # Skills and # Languages, use one bullet per item. - Remove OCR/layout noise. - Do not output placeholders like Not specified. - If uncertain, omit the field/line rather than invent. CV text: {req.text.strip()} """.strip() parsed = _ollama_generate_json(prompt) return { "confidence": parsed.get("confidence"), "reason": parsed.get("reason"), "normalized_text": parsed.get("normalized_text"), } @app.post("/cv/classify-block") async def classify_cv_block(req: CvClassifyBlockRequest): prompt = f""" You classify one CV text block into structured JSON. Return ONLY valid JSON with this exact shape: {{ "section": "Contact|Professional Summary|Work Experience|Education|Skills|Languages|Interests|Other", "confidence": 0.0, "reason": "short reason", "title": string|null, "company": string|null, "location": string|null, "start": string|null, "end": string|null, "bullets": string[], "summary": string[], "skills": string[] }} Rules: - Preserve facts only. - section must be one of the listed values. - Use Work Experience only for job/employment blocks. - Use Education only for degree/course/certification blocks. - For Contact blocks, keep title/company/start/end null and bullets/summary/skills empty. - For Professional Summary blocks, prefer summary for concise summary lines and keep bullets empty unless the source is already bullet-like. - For Skills blocks, prefer skills for normalized skill items and keep title/company/start/end null. - For non-work and non-education blocks, title/company/start/end should usually be null. - location must look like a place, not a sentence. - dates must be one of: year, month+year, dd/mm/yyyy, Present, Current. - bullets should only be concrete tasks/achievements/details, not titles, companies, dates, or headings. - skills should be short normalized skill/tool terms, not sentences. - If unsure, choose Other and keep fields null/empty. Block: {req.block.strip()} """.strip() parsed = _ollama_generate_json(prompt) return { "section": parsed.get("section") or "Other", "confidence": parsed.get("confidence"), "reason": parsed.get("reason"), "title": parsed.get("title"), "company": parsed.get("company"), "location": parsed.get("location"), "start": parsed.get("start"), "end": parsed.get("end"), "bullets": parsed.get("bullets") or [], "summary": parsed.get("summary") or [], "skills": parsed.get("skills") or [], } @app.post("/cv/rewrite") async def rewrite_cv(req: RewriteRequest): prompt = f""" You are an expert CV and resume writer. Rewrite the candidate CV into a polished, factual CV tailored to the target role. Return ONLY the final CV text. No analysis. No commentary. No JSON. No markdown code fences. No recruiter notes. Non-negotiable rules: - Preserve facts only. Never invent employers, dates, locations, salaries, education, qualifications, technologies, metrics, or achievements. - Never output sections like 'Role summary', 'What the company wants most', 'Keywords to mirror', 'Interview focus', 'Top hard skills', or similar analysis headings. - Do not describe the job ad. Rewrite the candidate CV. - Use crisp CV language, not prose about what the company wants. - Keep the output directly usable as a CV. - If rewriting the whole CV, output a complete CV with sensible headings and bullets. - If rewriting only one section, return only that rewritten section. - Keep bullets concrete and concise. - If a fact is not present in the source CV, omit it. Preferred whole-CV structure when the source supports it: # Contact # Professional Summary # Work Experience # Education # Skills # Certifications # Projects # Languages # Interests Instruction: {req.instruction.strip()} Candidate source CV: {req.text.strip()} """.strip() rewritten = _ollama_generate_text(prompt).strip() if not rewritten: raise HTTPException(status_code=502, detail="Ollama returned an empty rewrite.") return {"rewritten_text": rewritten} @app.post("/summarize") async def summarize(req: SummarizeRequest): if req.min_length >= req.max_length: raise HTTPException(status_code=400, detail="min_length must be smaller than max_length.") key = _key(req.text, req.max_length, req.min_length, req.top_skills) if key in cache: return {"summary": cache[key], "cached": True} info = _role_focused_excerpt(req.text) summary = _model_summarize(info["focused_input"], req.max_length, req.min_length) ranked_tech = [] for t in _rank_tech_skills(info["tech"]): if t not in ranked_tech: ranked_tech.append(t) uniq_soft = [] for s in info["soft"]: if s not in uniq_soft: uniq_soft.append(s) lines = ["Role summary:", summary] if info["requirements"]: lines.append("") lines.append("What the company wants most:") for x in info["requirements"][:5]: lines.append(f"- {_trim_line(x)}") if ranked_tech: lines.append("") lines.append("Top hard skills:") for skill in ranked_tech[: req.top_skills]: lines.append(f"- {skill}") if info["keywords"]: lines.append("") lines.append("Keywords to mirror:") for keyword in info["keywords"][:5]: lines.append(f"- {keyword}") if info["responsibilities"]: lines.append("") lines.append("What you would be doing:") for x in info["responsibilities"][:4]: lines.append(f"- {_trim_line(x)}") if info["nice"]: lines.append("") lines.append("Nice to have:") for x in info["nice"][:3]: lines.append(f"- {_trim_line(x)}") if uniq_soft: lines.append("") lines.append("Relevant soft skills:") for soft in uniq_soft[:5]: lines.append(f"- {soft}") lines.append("") lines.append("Interview focus:") if info["screen_focus"]: for x in info["screen_focus"]: lines.append(f"- Be ready to prove: {_trim_line(x)}") elif info["requirements"]: for x in info["requirements"][:3]: lines.append(f"- Prepare examples that demonstrate: {_trim_line(x)}") elif ranked_tech: for x in ranked_tech[:3]: lines.append(f"- Be ready to explain your hands-on experience with {x}") else: lines.append("- Prepare examples showing relevant impact, collaboration, and delivery.") out = "\n".join(lines).strip() cache[key] = out return {"summary": out, "cached": False} def _normalize_text(value: str) -> str: value = value.replace("\x00", " ") return re.sub(r"\s+", " ", value).strip() def _ocr_image(image: Image.Image) -> str: if image.mode not in ("RGB", "L"): image = image.convert("RGB") text = pytesseract.image_to_string(image, lang=OCR_LANGUAGES) return _normalize_text(text) def _extract_pdf_text(data: bytes) -> tuple[str, bool, int]: page_count = 0 extracted_pages = [] try: reader = PdfReader(io.BytesIO(data)) page_count = len(reader.pages) for page in reader.pages: extracted_pages.append(page.extract_text() or "") except Exception: extracted_pages = [] text = _normalize_text("\n".join(extracted_pages)) if len(text) >= 80: return text, False, page_count doc = fitz.open(stream=data, filetype="pdf") page_count = doc.page_count ocr_pages = [] for page in doc: pix = page.get_pixmap(matrix=fitz.Matrix(2, 2), alpha=False) image = Image.open(io.BytesIO(pix.tobytes("png"))) ocr_pages.append(_ocr_image(image)) doc.close() return _normalize_text("\n".join(ocr_pages)), True, page_count def _extract_docx_text(data: bytes) -> str: document = Document(io.BytesIO(data)) parts = [p.text.strip() for p in document.paragraphs if p.text and p.text.strip()] return _normalize_text("\n".join(parts)) def _extract_plain_text(data: bytes) -> str: return _normalize_text(data.decode("utf-8", errors="ignore")) @app.post("/extract-text") async def extract_text(file: UploadFile = File(...)): filename = file.filename or "document" extension = "." + filename.rsplit(".", 1)[1].lower() if "." in filename else "" data = await file.read() if not data: raise HTTPException(status_code=400, detail="The uploaded file was empty.") if len(data) > MAX_EXTRACT_FILE_BYTES: raise HTTPException(status_code=400, detail="The uploaded file is too large for AI extraction.") try: if extension in {".txt", ".md"}: text = _extract_plain_text(data) ocr_used = False page_count = None elif extension == ".docx": text = _extract_docx_text(data) ocr_used = False page_count = None elif extension == ".pdf": text, ocr_used, page_count = _extract_pdf_text(data) elif extension in IMAGE_EXTENSIONS: image = Image.open(io.BytesIO(data)) text = _ocr_image(image) ocr_used = True page_count = 1 else: raise HTTPException(status_code=400, detail="This file type is not supported for AI extraction.") except HTTPException: raise except Exception as exc: raise HTTPException(status_code=500, detail=f"AI extraction failed: {exc}") from exc if not text: raise HTTPException(status_code=422, detail="AI extraction did not find readable text in the uploaded file.") return { "text": text, "ocr_used": ocr_used, "content_type": file.content_type, "page_count": page_count, "characters": len(text), "file_name": filename, }