HTML table row submit and post to Flask server

Question

What I have is this in my HTML code:

<table id="example" class="table table-striped">
<thead>
    <tr>
        <th scope="col">Index</th>
        <th scope="col">Col2</th>
        <th scope="col">Col3</th>
        <th scope="col">Col4</th>
    </tr>
</thead>
<tbody>
 {% for item in rows %}
        <tr>
            <td><button formtarget="_blank"
                        name="input" type="submit"
                        formaction="/get"
                        value={{item[0]}}>{{item[0]}}</button></td>
            <td>{{ item[1] }}</td>
            <td>{{ item[2] }}</td>
            <td>{{ item[3] }}</td>
        </tr>
    {% endfor %}

Notice that I am adding button as type 'submit' to send item[0] which is essentially the row id of a sqlite3 table back to Flask server view function '/get'. My Flask '/get' function is as follows:

 @app.route('/get', methods =['GET', 'POST'])
    def getfmhtml():
    input = str()
    if request.method == 'POST':
        input = int(request.form['graph'])
        return render_template('index.html', input = input)

When I click the button in a row in Index column however, no value item[0] is posted to the server (i.e. nothing happens, no error either). I want to know what's the problem in my code. I want to Post the row id from index column back to my Flask server.

Answer 1

posting below as per suggestion from Gnudiff that worked. Enclosing button in form tag post the value back to the server:

{% for item in rows %}
        <tr>
            <td><form action="/get" method="POST"><button formtarget="_blank"
                        name="input" type="submit"
                        formaction="/get"
                        value={{item[0]}}>{{item[0]}}</button>
            </form>
            </td>
            <td>{{ item[1] }}</td>
            <td>{{ item[2] }}</td>
            <td>{{ item[3] }}</td>
        </tr>
    {% endfor %}