内部サーバエラーでメール送信できない

フォームの内容確認をGmailで送ろうとしているのですが
Internal Server Error
The server encountered an internal error and was unable to complete your request. Either the server is overloaded or there is an error in the application.

このような文面が実行すると出ます

実現したいこと

ここに実現したいことを箇条書きで書いてください。

▲▲機能を動作するようにする

発生している問題・エラーメッセージ

PowerShell
1[2023-01-06 19:30:51,183] ERROR in app: Exception on /contact/complete [POST]
2Traceback (most recent call last):
3  File "C:\Users\tsuch\venv\Lib\site-packages\flask_mail.py", line 492, in send
4    message.send(connection)
5  File "C:\Users\tsuch\venv\Lib\site-packages\flask_mail.py", line 427, in send
6    connection.send(self)
7  File "C:\Users\tsuch\venv\Lib\site-packages\flask_mail.py", line 177, in send
8    assert message.sender, (
9AssertionError: The message does not specify a sender and a default sender has not been configured
10
11During handling of the above exception, another exception occurred:
12
13Traceback (most recent call last):
14  File "C:\Users\tsuch\venv\Lib\site-packages\flask\app.py", line 2525, in wsgi_app
15    response = self.full_dispatch_request()
16               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
17  File "C:\Users\tsuch\venv\Lib\site-packages\flask\app.py", line 1822, in full_dispatch_request
18    rv = self.handle_user_exception(e)
19         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
20  File "C:\Users\tsuch\venv\Lib\site-packages\flask\app.py", line 1820, in full_dispatch_request
21    rv = self.dispatch_request()
22         ^^^^^^^^^^^^^^^^^^^^^^^
23  File "C:\Users\tsuch\venv\Lib\site-packages\flask\app.py", line 1796, in dispatch_request
24    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)
25           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
26  File "C:\Users\tsuch\flaskbook\apps\minimalapp\app.py", line 109, in contact_complete
27    send_email(
28  File "C:\Users\tsuch\flaskbook\apps\minimalapp\app.py", line 129, in send_email
29    mail.send(msg)
30  File "C:\Users\tsuch\venv\Lib\site-packages\flask_mail.py", line 491, in send
31    with self.connect() as connection:
32  File "C:\Users\tsuch\venv\Lib\site-packages\flask_mail.py", line 152, in __exit__
33    self.host.quit()
34  File "C:\Users\tsuch\AppData\Local\Programs\Python\Python311\Lib\smtplib.py", line 1004, in quit
35    res = self.docmd("quit")
36          ^^^^^^^^^^^^^^^^^^
37  File "C:\Users\tsuch\AppData\Local\Programs\Python\Python311\Lib\smtplib.py", line 431, in docmd
38    self.putcmd(cmd, args)
39  File "C:\Users\tsuch\AppData\Local\Programs\Python\Python311\Lib\smtplib.py", line 378, in putcmd
40    self.send(f'{s}{CRLF}')
41  File "C:\Users\tsuch\AppData\Local\Programs\Python\Python311\Lib\smtplib.py", line 365, in send
42    raise SMTPServerDisconnected('please run connect() first')
43smtplib.SMTPServerDisconnected: please run connect() first
44127.0.0.1 - - [06/Jan/2023 19:30:51] "POST /contact/complete HTTP/1.1" 500 -
45

該当のソースコード

python
1# loggingをインポート
2import logging
3import os
4
5from email_validator import EmailNotValidError, validate_email
6
7# Flaskクラスをインポート
8from flask import (
9    Flask,
10    current_app,
11    flash,
12    g,
13    redirect,
14    render_template,
15    request,
16    url_for,
17)
18from flask_debugtoolbar import DebugToolbarExtension
19from flask_mail import Mail, Message
20
21# Flaskクラスをインスタンス化
22app = Flask(__name__)
23# secret_keyの追加
24app.config["SECRET_KEY"] = "2AZSMss3p5QPbcY2hBsJ"
25# ログレベルの設定
26app.logger.setLevel(logging.DEBUG)
27
28app.logger.debug("DEBUG")
29app.logger.info("INFO")
30app.logger.warning("WARNING")
31app.logger.error("ERROR")
32app.logger.critical("CRITICAL")
33
34
35app.config["DEBUG_TB_INTERCEPT_REDIRECTS"] = False
36toolbor = DebugToolbarExtension(app)
37
38# URLと実行する関数をマッピング
39@app.route("/")
40def index():
41    return "Hello,Flaskbook!"
42
43
44@app.route("/hello/<name>", methods=["GET", "POST"], endpoint="hello-endpoint")
45def hello(name):
46    return f"Hello, {name}!"
47
48
49@app.route("/name/<name>")
50def show_name(name):
51    return render_template("index.html", name=name)
52
53
54with app.test_request_context():
55    # /
56    print(url_for("index"))
57    # /hello/world
58    print(url_for("hello-endpoint", name="world"))
59    # /name/Rikuo?page=1
60    print(url_for("show_name", name="Rikuo", page="1"))
61
62ctx = app.app_context()
63ctx.push()
64
65print(current_app.name)
66
67g.connection = "connection"
68print(g.connection)
69
70with app.test_request_context("/users?update=ture"):
71    print(request.args.get("updated"))
72
73
74@app.route("/contact")
75def contact():
76    return render_template("contact.html")
77
78
79@app.route("/contact/complete", methods=["GET", "POST"])
80def contact_complete():
81    if request.method == "POST":
82        username = request.form["username"]
83        email = request.form["email"]
84        description = request.form["description"]
85        is_valid = True
86
87        if not username:
88            flash("ユーザ名は必須です")
89            is_valid = False
90
91        if not email:
92            flash("メールアドレスは必須です")
93            is_valid = False
94
95        try:
96            validate_email(email)
97        except EmailNotValidError:
98            flash("メールアドレスの形式で入力してください")
99            is_valid = False
100
101        if not description:
102            flash("問い合わせ内容は必須です")
103            is_valid = False
104
105        if not is_valid:
106            return redirect(url_for("contact"))
107
108        # メールを送る
109        send_email(
110            email,
111            "お問い合わせありがとうございました。",
112            "contact_mail",
113            username=username,
114            description=description,
115        )
116
117        flash("問い合わせ内容はメールにて送信しました。問い合わせありがとうございます。")
118
119        return redirect(url_for("contact_complete"))
120
121    return render_template("contact_complete.html")
122
123
124def send_email(to, subject, template, **kwargs):
125    """メールを送信する関数"""
126    msg = Message(subject, recipients=[to])
127    msg.body = render_template(template + ".txt", **kwargs)
128    msg.html = render_template(template + ".html", **kwargs)
129    mail.send(msg)
130
131
132# Mailクラスのコンフィグを追加
133app.config["MAIL_SERVER"] = os.environ.get("MAIL_SERVER")
134app.config["MAIL_PORT"] = os.environ.get("MAIL_PORT")
135app.config["MAIL_USE_TLS"] = os.environ.get("MAIL_USE_TLS")
136app.config["MAIL_USERNAME"] = os.environ.get("MAIL_USERNAME")
137app.config["MAIL_PASSWORD"] = os.environ.get("MAIL_PASSWORD")
138app.config["MAIL_DEFAULT_SENDER"] = os.environ.get("MAIL_DEFAULT_SENDER")
139
140mail = Mail(app)
141