server.py

from functools import wraps
from flask import (
    Flask,
    jsonify,
    request,
    render_template_string,
    abort,
    send_from_directory,
    send_file,
)
from flask_cors import CORS
import unicodedata
import markdown
import time
import os
import gc
import base64
from io import BytesIO
from random import randint
import hashlib
import chromadb
import posthog
import torch
from chromadb.config import Settings
from sentence_transformers import SentenceTransformer
from werkzeug.middleware.proxy_fix import ProxyFix
from transformers import AutoTokenizer, AutoProcessor, pipeline
from transformers import AutoModelForCausalLM, AutoModelForSeq2SeqLM
from transformers import BlipForConditionalGeneration, GPT2Tokenizer
from PIL import Image
import webuiapi
from colorama import Fore, Style, init as colorama_init


colorama_init()

port = 7860
host = "0.0.0.0"


summarization_model = (
    "Qiliang/bart-large-cnn-samsum-ChatGPT_v3"
)
classification_model = (
    "joeddav/distilbert-base-uncased-go-emotions-student"
)
captioning_model = (
    "Salesforce/blip-image-captioning-large"
)

device_string = "cpu"
device = torch.device(device_string)
torch_dtype = torch.float32 if device_string == "cpu" else torch.float16

embedding_model = 'sentence-transformers/all-mpnet-base-v2'

print("Initializing a text summarization model...")

summarization_tokenizer = AutoTokenizer.from_pretrained(summarization_model)
summarization_transformer = AutoModelForSeq2SeqLM.from_pretrained(
summarization_model, torch_dtype=torch_dtype).to(device)

print("Initializing a sentiment classification pipeline...")
classification_pipe = pipeline(
        "text-classification",
        model=classification_model,
        top_k=None,
        device=device,
        torch_dtype=torch_dtype,
    )

print("Initializing an image captioning model...")
captioning_processor = AutoProcessor.from_pretrained(captioning_model)
if "blip" in captioning_model:
    captioning_transformer = BlipForConditionalGeneration.from_pretrained(
        captioning_model, torch_dtype=torch_dtype
    ).to(device)
else:
    captioning_transformer = AutoModelForCausalLM.from_pretrained(
        captioning_model, torch_dtype=torch_dtype
    ).to(device)


print("Initializing ChromaDB")

# disable chromadb telemetry
posthog.capture = lambda *args, **kwargs: None
chromadb_client = chromadb.Client(Settings(anonymized_telemetry=False))
chromadb_embedder = SentenceTransformer(embedding_model)
chromadb_embed_fn = chromadb_embedder.encode

# Flask init
app = Flask(__name__)
CORS(app)  # allow cross-domain requests
app.config["MAX_CONTENT_LENGTH"] = 100 * 1024 * 1024

app.wsgi_app = ProxyFix(
    app.wsgi_app, x_for=2, x_proto=1, x_host=1, x_prefix=1
)

def get_real_ip():
    return request.remote_addr

def caption_image(raw_image: Image, max_new_tokens: int = 20) -> str:
    inputs = captioning_processor(raw_image.convert("RGB"), return_tensors="pt").to(
        device, torch_dtype
    )
    outputs = captioning_transformer.generate(**inputs, max_new_tokens=max_new_tokens)
    caption = captioning_processor.decode(outputs[0], skip_special_tokens=True)
    return caption


def classify_text(text: str) -> list:
    output = classification_pipe(
        text,
        truncation=True,
        max_length=classification_pipe.model.config.max_position_embeddings,
    )[0]
    return sorted(output, key=lambda x: x["score"], reverse=True)


def summarize_chunks(text: str, params: dict) -> str:
    try:
        return summarize(text, params)
    except IndexError:
        print(
            "Sequence length too large for model, cutting text in half and calling again"
        )
        new_params = params.copy()
        new_params["max_length"] = new_params["max_length"] // 2
        new_params["min_length"] = new_params["min_length"] // 2
        return summarize_chunks(
            text[: (len(text) // 2)], new_params
        ) + summarize_chunks(text[(len(text) // 2) :], new_params)


def summarize(text: str, params: dict) -> str:
    # Tokenize input
    inputs = summarization_tokenizer(text, return_tensors="pt").to(device)
    token_count = len(inputs[0])

    bad_words_ids = [
        summarization_tokenizer(bad_word, add_special_tokens=False).input_ids
        for bad_word in params["bad_words"]
    ]
    summary_ids = summarization_transformer.generate(
        inputs["input_ids"],
        num_beams=2,
        max_new_tokens=max(token_count, int(params["max_length"])),
        min_new_tokens=min(token_count, int(params["min_length"])),
        repetition_penalty=float(params["repetition_penalty"]),
        temperature=float(params["temperature"]),
        length_penalty=float(params["length_penalty"]),
        bad_words_ids=bad_words_ids,
    )
    summary = summarization_tokenizer.batch_decode(
        summary_ids, skip_special_tokens=True, clean_up_tokenization_spaces=True
    )[0]
    summary = normalize_string(summary)
    return summary


def normalize_string(input: str) -> str:
    output = " ".join(unicodedata.normalize("NFKC", input).strip().split())
    return output

@app.before_request
def before_request():
    # Request time measuring
    request.start_time = time.time()

    # Checks if an API key is present and valid, otherwise return unauthorized
    # The options check is required so CORS doesn't get angry
    try:
        if request.method != 'OPTIONS' and getattr(request.authorization, 'token', '') != os.environ['sekrit_password']:
            print(f"WARNING: Unauthorized API key access from {request.remote_addr}")
            response = jsonify({ 'error': '401: Invalid API key' })
            response.status_code = 401
            return response
    except Exception as e:
        print(f"API key check error: {e}")
        return "401 Unauthorized\n{}\n\n".format(e), 401



@app.after_request
def after_request(response):
    duration = time.time() - request.start_time
    response.headers["X-Request-Duration"] = str(duration)
    return response

@app.route("/", methods=["GET"])
def index():
    with open("./README.md", "r", encoding="utf8") as f:
        content = f.read()
    return render_template_string(markdown.markdown(content, extensions=["tables"]))


@app.route("/api/modules", methods=["GET"])
def get_modules():
    return jsonify({"modules": ['chromadb','summarize','classify','caption']})

@app.route("/api/chromadb", methods=["POST"])
def chromadb_add_messages():
    data = request.get_json()
    if "chat_id" not in data or not isinstance(data["chat_id"], str):
        abort(400, '"chat_id" is required')
    if "messages" not in data or not isinstance(data["messages"], list):
        abort(400, '"messages" is required')

    ip = get_real_ip()
    chat_id_md5 = hashlib.md5(f'{ip}-{data["chat_id"]}'.encode()).hexdigest()
    collection = chromadb_client.get_or_create_collection(
        name=f"chat-{chat_id_md5}", embedding_function=chromadb_embed_fn
    )

    documents = [m["content"] for m in data["messages"]]
    ids = [m["id"] for m in data["messages"]]
    metadatas = [
        {"role": m["role"], "date": m["date"], "meta": m.get("meta", "")}
        for m in data["messages"]
    ]

    if len(ids) > 0:
        collection.upsert(
            ids=ids,
            documents=documents,
            metadatas=metadatas,
        )

    return jsonify({"count": len(ids)})


@app.route("/api/chromadb/query", methods=["POST"])
def chromadb_query():
    data = request.get_json()
    if "chat_id" not in data or not isinstance(data["chat_id"], str):
        abort(400, '"chat_id" is required')
    if "query" not in data or not isinstance(data["query"], str):
        abort(400, '"query" is required')

    if "n_results" not in data or not isinstance(data["n_results"], int):
        n_results = 1
    else:
        n_results = data["n_results"]

    ip = get_real_ip()
    chat_id_md5 = hashlib.md5(f'{ip}-{data["chat_id"]}'.encode()).hexdigest()
    collection = chromadb_client.get_or_create_collection(
        name=f"chat-{chat_id_md5}", embedding_function=chromadb_embed_fn
    )

    n_results = min(collection.count(), n_results)

    messages = []
    if n_results > 0:
        query_result = collection.query(
            query_texts=[data["query"]],
            n_results=n_results,
        )
    
        documents = query_result["documents"][0]
        ids = query_result["ids"][0]
        metadatas = query_result["metadatas"][0]
        distances = query_result["distances"][0]
    
        messages = [
            {
                "id": ids[i],
                "date": metadatas[i]["date"],
                "role": metadatas[i]["role"],
                "meta": metadatas[i]["meta"],
                "content": documents[i],
                "distance": distances[i],
            }
            for i in range(len(ids))
        ]

    return jsonify(messages)
    
@app.route("/api/chromadb/purge", methods=["POST"])
def chromadb_purge():
    data = request.get_json()
    if "chat_id" not in data or not isinstance(data["chat_id"], str):
        abort(400, '"chat_id" is required')

    ip = get_real_ip()
    chat_id_md5 = hashlib.md5(f'{ip}-{data["chat_id"]}'.encode()).hexdigest()
    collection = chromadb_client.get_or_create_collection(
        name=f"chat-{chat_id_md5}", embedding_function=chromadb_embed_fn
    )

    deleted = collection.delete()
    print("ChromaDB embeddings deleted", len(deleted))

    return 'Ok', 200

@app.route("/api/summarize", methods=["POST"])
def api_summarize():
    data = request.get_json()

    if "text" not in data or not isinstance(data["text"], str):
        abort(400, '"text" is required')

    params = {
    "temperature": 1.0,
    "repetition_penalty": 1.0,
    "max_length": 500,
    "min_length": 200,
    "length_penalty": 1.5,
    "bad_words": [
        "\n",
        '"',
        "*",
        "[",
        "]",
        "{",
        "}",
        ":",
        "(",
        ")",
        "<",
        ">",
        "Â",
        "The text ends",
        "The story ends",
        "The text is",
        "The story is",
    ],
}

    if "params" in data and isinstance(data["params"], dict):
        params.update(data["params"])

    print("Summary input:", data["text"], sep="\n")
    summary = summarize_chunks(data["text"], params)
    print("Summary output:", summary, sep="\n")
    gc.collect()
    return jsonify({"summary": summary})



@app.route("/api/classify", methods=["POST"])
def api_classify():
    data = request.get_json()

    if "text" not in data or not isinstance(data["text"], str):
        abort(400, '"text" is required')

    print("Classification input:", data["text"], sep="\n")
    classification = classify_text(data["text"])
    print("Classification output:", classification, sep="\n")
    gc.collect()
    return jsonify({"classification": classification})


@app.route("/api/classify/labels", methods=["GET"])
def api_classify_labels():
    classification = classify_text("")
    labels = [x["label"] for x in classification]
    return jsonify({"labels": labels})


app.run(host=host, port=port)