Progress Bar

             from fasthtml.common import H3, Button, Div, HttpHeader, Style, fast_app

css = """
.progress {
    height: 20px;
    margin-bottom: 20px;
    overflow: hidden;
    background-color: #f5f5f5;
    border-radius: 4px;
    box-shadow: inset 0 1px 2px rgba(0,0,0,.1);
}
.progressbar {
    float: left;
    width: 0%;
    height: 100%;
    font-size: 12px;
    line-height: 20px;
    color: #fff;
    text-align: center;
    background-color: #337ab7;
    -webkit-box-shadow: inset 0 -1px 0 rgba(0,0,0,.15);
    box-shadow: inset 0 -1px 0 rgba(0,0,0,.15);
    -webkit-transition: width .6s ease;
    -o-transition: width .6s ease;
    transition: width .6s ease !important;
}
"""

app, rt = fast_app(hdrs=[Style(css)])

current = 1


@app.get
def page():
    return Div(hx_target="this", hx_swap="outerHTML")(
        H3("Start Progress"),
        Button("Start Job", hx_post=start.rt(), cls="btn primary"),
    )


@app.post
def start():
    global current
    current = 1
    return Div(hx_trigger="done", hx_get=job_finished.rt(), hx_swap="outerHTML", hx_target="this")(
        H3("Running", role="status", id="pblabel", tabindex="-1", autofocus=""),
        Div(hx_get=progress_bar.rt(), hx_trigger="every 600ms", hx_target="this", hx_swap="innerHTML")(
            progress_bar(),
        ),
    )


@app.get
def progress_bar():
    global current
    if current <= 100:
        current += 20
        return Div(cls="progress")(
            Div(style=f"width:{current - 20}%", id="THIS_ID_IS_INDISPENSIBLE", cls="progressbar"),
        )
    return HttpHeader("HX-Trigger", "done")


@app.get
def job_finished():
    return Div(hx_swap="outerHTML", hx_target="this")(
        H3("Complete", role="status", id="pblabel", tabindex="-1", autofocus=""),
        Div(Div(style="width:100%", id="THIS_ID_IS_INDISPENSIBLE", cls="progressbar"), cls="progress"),
        Button("Restart Job", hx_post=start.rt(), cls="btn primary show"),
    )
           

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