# Update PlotlyJS plot in Dash with async data
**URL:** https://discourse.julialang.org/t/update-plotlyjs-plot-in-dash-with-async-data/66298
**Category:** General Usage
**Tags:** plotlyjs, dash
**Created:** [August 12, 2021, 9:11pm UTC](https://discourse.julialang.org/t/update-plotlyjs-plot-in-dash-with-async-data/66298 "2021-08-12T21:11:52Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@mzaffalon](https://discourse.julialang.org/u/mzaffalon)
#### Post date: [August 12, 2021, 9:11pm UTC](https://discourse.julialang.org/t/update-plotlyjs-plot-in-dash-with-async-data/66298/1 "2021-08-12T21:11:52Z")
I would like to update a PlotlyJS plot inside Dash with data that is generated asynchronously. A MnWE (minimal not-working example) is here:
```julia
using Dash, DashHtmlComponents, DashCoreComponents, PlotlyBase
app = dash()
plt = Plot(scatter(; y = randn(10)))
function data_producer(pl)
while true
extendtraces!(pl, Dict(:y => [[randn()]]))
sleep(1)
end
end
# generate the data asynchronously
@async data_producer(plt)
app.layout = html_div() do
dcc_graph(id = "figure", figure = plt)
end
run_server(app, "127.0.0.1", 8050, debug = true)
```
How can I trigger the redrawing of the plot?
---
### Author:  [@mzaffalon](https://discourse.julialang.org/u/mzaffalon)
#### Post date: [August 27, 2021, 6:41am UTC](https://discourse.julialang.org/t/update-plotlyjs-plot-in-dash-with-async-data/66298/2 "2021-08-27T06:41:52Z")
The missing element was generating the event with `dcc_interval`. Here is the complete script that updates the plot every two seconds while data is produced at a rate of a new data point per second.
```julia
using Dash, DashHtmlComponents, DashCoreComponents, PlotlyBase
plt = Plot(scatter(; y = randn(10)))
function data_producer(pl)
while true
extendtraces!(pl, Dict(:y => [[randn()]]))
sleep(1)
end
end
# generate the data asynchronously
@async data_producer(plt)
app = dash()
app.layout = html_div() do
dcc_graph(id="theplot", figure=plt),
dcc_interval(id="plot-updater", interval=2000)
end
callback!(app,
Output("theplot", "figure"),
[Input("plot-updater", "n_intervals")]) do n
plt
end
run_server(app, "127.0.0.1", 8050, debug=true)
```
`dcc_interval` is currently missing from the Julia [documentation](https://dash-julia.plotly.com/dash-core-components) but it is available at the REPL help `help?> dcc_interval`.
---
### Author:  [@cepel](https://discourse.julialang.org/u/cepel)
#### Post date: [October 17, 2021, 7:42pm UTC](https://discourse.julialang.org/t/update-plotlyjs-plot-in-dash-with-async-data/66298/3 "2021-10-17T19:42:23Z")
Hey @mzaffalon
While working on VSCode, I can see the “dcc\_interval” component in Dash Julia. Let me know if you are still having a problem, so I can develop a tiny example.
---
### Author:  [@mzaffalon](https://discourse.julialang.org/u/mzaffalon)
#### Post date: [October 19, 2021, 8:13pm UTC](https://discourse.julialang.org/t/update-plotlyjs-plot-in-dash-with-async-data/66298/4 "2021-10-19T20:13:59Z")
@cepel: thank you for the update.
I stopped working with Dash as it was not the solution I needed for my problem.