voicegardens/vocoder/server.py

"""Flask server for the vocoder back-end."""

import os.path
from pathlib import Path

from flask import Flask, render_template, request, send_from_directory
from flask_cors import CORS
from werkzeug.utils import secure_filename

ALLOWED_UPLOAD_EXTENSIONS = {"wav"}
UPLOAD_DIRECTORY = Path(__file__).parent / "archive"
MAXIMUM_FILE_SIZE = 16 * 1024 * 1024  # 16 MB

app = Flask(__name__)

app.config["UPLOAD_FOLDER"] = UPLOAD_DIRECTORY
app.config["MAX_CONTENT_LENGTH"] = MAXIMUM_FILE_SIZE

CORS(app)


@app.route("/")
def root():
    """Serve the main homepage."""
    return render_template("index.html")


def allowed_file(filename):
    """Validate uploaded file extensions."""
    extension = filename.rsplit(".", 1)[1].lower()
    return "." in filename and extension in ALLOWED_UPLOAD_EXTENSIONS


@app.route("/add-to-archive", methods=["POST"])
def add_to_archive():
    """Archive recordings sent from the front-end."""
    try:
        file = request.files["file"]
    except KeyError:
        return ("Missing file for upload", 400)

    if not allowed_file(file.filename):
        return ("File extension not allowed", 400)

    secured = secure_filename(file.filename)
    file.save(os.path.join(app.config["UPLOAD_FOLDER"], secured))

    return ("file archived successfully", 201)


@app.route("/archives/<filename>")
def uploaded_file(filename):
    """Retrieve an uploaded recording."""
    return send_from_directory(app.config["UPLOAD_FOLDER"], filename)


@app.route("/archive")
def archive():
    """Serve the archive listing."""
    listing = os.listdir(UPLOAD_DIRECTORY)
    files = filter(lambda f: f.endswith(".wav"), listing)
    return render_template("archive.html", files=files)