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Tech Setup guide: <https://docs.google.com/document/d/136OtdLNrYOiYsOXTYPluxnFlnkyWpyZ08rp-7sq6PFc/edit?usp=sharing>

set the channel topic: Tech Setup guide: <https://docs.google.com/document/d/136OtdLNrYOiYsOXTYPluxnFlnkyWpyZ08rp-7sq6PFc/edit?usp=sharing>

Prefect Certification Course Tech Setup.pdf

Hello! After running the flowtest.py I get this error: `httpx.ConnectError: [Errno 8] nodename nor servname provided, or not known` Any idea how I could get to the _`&lt;Response [200 OK]&gt;`_ . I followed the instructions provided in the google doc

Hmm. Sorry to hear that. Are you usually able to run Python scripts ok?

What happens if you run `prefect server start`

Screenshot 2023-08-16 at 9.45.38 AM.png

Cool. What if you click on/navigate to the URL in the message. <http://127.0.0.1:4200>

Screenshot 2023-08-16 at 9.47.09 AM.png

It’s picking up that the flows you ran didn’t complete. Can you please copy paste the code you ran below?

Thank you. Can you please copy paste the the code in the file?

```import httpx
from prefect import flow

@flow
def test_flow():
    res = httpx.get("<https://example.com>")
    print(res)

if __name__ == "__main__":
    test_flow()```

Try adding `verify=False` as a second argument in the httpx.get call.

Screenshot 2023-08-16 at 9.56.57 AM.png

Screenshot 2023-08-16 at 9.56.48 AM.png

Screenshot 2023-08-16 at 9.56.48 AM.png,Screenshot 2023-08-16 at 9.56.57 AM.png

What’s the result of running a script with the following contents only:

```import httpx
httpx.get('<https://www.example.org/>')```

Ok. We’re getting somewhere.

How about
```import requests
requests.get('<https://www.example.org/>')```

`requests.exceptions.ConnectionError: HTTPSConnectionPool(host='<http://www.example.org|www.example.org>', port=443): Max retries exceeded with url: / (Caused by NewConnectionError('&lt;urllib3.connection.HTTPSConnection object at 0x103553f70&gt;: Failed to establish a new connection: [Errno 8] nodename nor servname provided, or not known'))`

ok. Thank you.

Does running `curl <http://example.com|example.com>` work?

`curl: (6) Could not resolve host: <http://example.com|example.com>`

You’re running this in VSCode terminal on a mac, is that right? What happens if you open a regular terminal window outside VSCode and run any of the above commands?

Right now you aren’t able to use your terminal to connect to anything at all, but you are able to use it to create a server that your browser can connect to and we’re having this conversation, so your machine can connect to the internet.

This Stack Overflow answer might be what you’re looking for: <https://stackoverflow.com/a/69530340/4590385>

The two answers under that one also look promising.

so it works when I change to "<https://www.google.com>"

Is <http://example.com|example.com> mandatory for the course?

Ok, so I connected to my company's VPN and it seems to work now

Screenshot 2023-08-16 at 10.30.49 AM.png

What's the reason for the flow "test-flow" to have three different run?

<http://Example.com|Example.com> is just an example website. Strange it works for google, but not <http://Example.com|Example.com>.

Does your company block some/most/all traffic from the terminal that isn’t through the VPN?

Glad it’s working. :slightly_smiling_face:

Not sure why it ran 3 times and is showing those 3 logged runs.

Welcome everyone! We’ll get started in just a few minutes. Until then, check out the questions below. :slightly_smiling_face:

I’ve used Prefect 1 (thumbs up or down emoji reaction)

Where are you coming from? thread or flag emoji

*101 Lab Instructions*
&gt; Use Open-Meteo API
&gt; • Write flow code that fetches other weather metrics
&gt; • Make at least 3 tasks in the flow
&gt; • Example: windspeed for the last hour:
&gt; _weather.json()[“hourly”][“windspeed_10m”][0]_
&gt; • Docs: <http://open-meteo.com/en/docs|open-meteo.com/en/docs>

PACC Aug 16 2023.pdf

Repo:
<https://github.com/discdiver/pacc-online-2023>

Please share your code from lab 101 in a thread here :thread:. Folks always report finding value in seeing how other people tackle the questions. :slightly_smiling_face:

```I'm in a triple backtick code block `````

```import httpx  # requests capability, but can work with async
from prefect import flow, task
import csv


@task
def fetch_weather(lat: float, lon: float):
    base_url = "<https://api.open-meteo.com/v1/forecast/>"
    weather = httpx.get(
        base_url,
        params=dict(latitude=lat, longitude=lon, hourly="temperature_2m"),
    )
    weather = float(weather.json()["hourly"]["temperature_2m"][0])
    return weather

@task
def get_wind(lat: float, lon: float):
    base_url = "<https://api.open-meteo.com/v1/forecast/>"
    weather = httpx.get(
        base_url,
        params=dict(latitude=lat, longitude=lon, hourly="windspeed_10m"),
    )
    weather = float(weather.json()["hourly"]["windspeed_10m"][0])
    return weather   


@task
def save_weather(weather):
    with open("weather.csv", "w+") as w:
        w.write(str(weather))
    return "Successfully wrote temp"








@flow
def pipeline(lat: float, lon: float):
    temp = fetch_weather(lat, lon)
    
    wind_speed = get_wind(lat, lon)

    weather_report = {
        1:wind_speed,
        2:temp
    }

    result = save_weather(weather_report)
    return result


if __name__ == "__main__":
    pipeline(38.9, -77.0)```

weather.py

Our group’s code, just prior to trying to make it async:

`import httpx`
```from prefect import flow, task                @task
def get_rain(lat: float, lon: float) -&gt; float:
    base_url = "<https://api.open-meteo.com/v1/forecast/>"
    weather = httpx.get(
        base_url,
        params=dict(latitude=lat, longitude=lon, hourly="precipitation"),
    )
    return float(weather.json()["hourly"]["precipitation"][0])

@task
def get_humidity(lat: float, lon: float) -&gt; float:
    base_url = "<https://api.open-meteo.com/v1/forecast/>"
    weather = httpx.get(
        base_url,
        params=dict(latitude=lat, longitude=lon, hourly="relativehumidity_2m"),
    )
    return float(weather.json()["hourly"]["relativehumidity_2m"][0])

@task
def get_temp(lat: float, lon: float) -&gt; float:
    base_url = "<https://api.open-meteo.com/v1/forecast/>"
    weather = httpx.get(
        base_url,
        params=dict(latitude=lat, longitude=lon, hourly="temperature_2m"),
    )
    return float(weather.json()["hourly"]["temperature_2m"][0])

@task
def print_results(temp: float, humidity: float, rain: float):
    print(f"Temperature : {temp}, Relative Humitidy : {humidity}, Rain : {rain}%")

@flow
def test_flow(lat: float, lon: float):
    temp = get_temp(lat, lon)
    humidity = get_humidity(lat, lon)
    rain = get_rain(lat, lon)
    print_results(temp, humidity, rain)


if __name__ == "__main__":
    test_flow(1, 1)```

```import httpx
from prefect import task, flow


@task
def fetch_weather(lat: float, lon: float):
    base_url = "<https://api.open-meteo.com/v1/forecast/>"
    weather = httpx.get(
        base_url,
        params=dict(latitude=lat, longitude=lon, hourly="temperature_2m"),
    )
    most_recent_temp = float(weather.json()["hourly"]["temperature_2m"][0])
    print(f"Most recent temp C: {most_recent_temp} degrees")
    return most_recent_temp

@task
def fetch_dewpoint(lat: float, lon: float):
    base_url = "<https://api.open-meteo.com/v1/forecast/>"
    weather = httpx.get(
        base_url,
        params=dict(latitude=lat, longitude=lon, hourly="dewpoint_2m"),
    )
    most_recent_dewpoint = float(weather.json()["hourly"]["dewpoint_2m"][0])
    print(f"Most recent dewpoint C: {most_recent_dewpoint} degrees")
    return most_recent_dewpoint
@task
def fetch_windspeed(lat: float, lon: float):
    base_url = "<https://api.open-meteo.com/v1/forecast/>"
    weather = httpx.get(
        base_url,
        params=dict(latitude=lat, longitude=lon, hourly="windspeed_10m"),
    )
    most_recent_windspeed = float(weather.json()["hourly"]["windspeed_10m"][0])
    print(f"Most recent windspeed C: {most_recent_windspeed} degrees")
    return most_recent_windspeed

@flow
def weather_pipeline(lat: float, lon: float):
    fetch_weather(lat, lon)

    fetch_dewpoint(lat, lon)
    
    fetch_windspeed(lat, lon)


if __name__ == "__main__":
    weather_pipeline(38.9, -77.0)```

```from prefect import flow, task, tags
from prefect.logging import get_run_logger
import httpx
from typing import List


def fetch_weather(lat: float, lon: float):
    logger = get_run_logger()
    base_url = "<https://api.open-meteo.com/v1/forecast/>"
    weather = httpx.get(
        base_url,
        params=dict(latitude=lat, longitude=lon, hourly="temperature_2m"),
    )
    most_recent_temp = float(weather.json()["hourly"]["temperature_2m"][0])
    <http://logger.info|logger.info>(f"Most recent temp C: {most_recent_temp} degrees")
    return most_recent_temp


@task(name="fetch_many")
def fetch_many_weather(lat:float):
    lon = -175
    temp_list = {}
    while lon &lt; 180:
        temp = fetch_weather(lat, lon)
        temp_list[lon] = temp
        lon += 5
    return temp_list


@task(name="save_weather_info")
def save_weather(temp: List[float]):
    with open("weather.csv", "w+") as w:
        w.write(str(temp))
    return "Successfully wrote temp"


@task(name="display")
def display(temp_list):
    logger = get_run_logger()
    <http://logger.info|logger.info>(temp_list)


@flow(name="weather_pipeline")
def pipeline(lat: float):
    temp = fetch_many_weather(lat)
    result = save_weather(temp)
    display(temp)
    return result


if __name__ == "__main__":
    pipeline(38.9)```

```from prefect import flow, task
import httpx

@task
def fetch_weather(lat: float, lon: float):
    base_url = "<https://api.open-meteo.com/v1/forecast/>"
    weather = httpx.get(
        base_url,
        params=dict(latitude=lat , longitude=lon , hourly="temperature_2m"),
    )
    most_recent_temp = float(weather.json()["hourly"]["temperature_2m"][0])
    return most_recent_temp

@task
def fetch_windspeed(lat: float, lon: float):
    base_url = "<https://api.open-meteo.com/v1/forecast/>"
    weather = httpx.get(
        base_url,
        params=dict(latitude=lat , longitude=lon , hourly="windspeed_10m"),
    )
    most_recent_windspeed = float(weather.json()["hourly"]["windspeed_10m"][0])
    return most_recent_windspeed

@task
def save_weather(temp: float):
    with open("weather.csv","w+") as w:
        w.write(str(temp))
    return "Successfully wrote temp"

@task
def save_windspeed(temp: float):
    with open("windspeed.csv","w+") as w:
        w.write(str(temp))
    return "Successfully wrote temp"


@flow
def pipeline(lat: float, lon: float):
    temp = fetch_weather(lat,lon)
    weather_result = save_weather(temp)
    windspeed = fetch_windspeed(lat,lon)
    windspeed_result = save_windspeed(windspeed)
    print(f"{weather_result} , {windspeed_result}")



if __name__ == "__main__":
    pipeline(38.9,-77.0)```

import httpx
from prefect import flow, task


@task
def get_url():
    return "<https://api.open-meteo.com/v1/forecast/>"

@task()
def fetch_weather(lat: float, lon: float, base_url):

    weather = httpx.get(base_url,
        params=dict(latitude=lat, longitude=lon, hourly="rain"),
    )
    #print(weather.json())
    most_recent_rain = float(weather.json()["hourly"]["rain"][0])
    print(f"Most recent rain C: {most_recent_rain} mm")
    return most_recent_rain

@task
def save_rain(rain):
    with open("weather.csv", "w+") as w:
        w.write(str(rain))
    return "Successfully wrote Windspeed"

@flow
def pipeline(lat: float, lon: float):
    base_url = get_url()
    rain = fetch_weather(lat, lon, base_url)
    result = save_rain(rain)
    return result


if _name_ == "_main_":
    pipeline(38.9, -77.0)

<https://github.com/taylor-curran/prefect-patterns/tree/main/flows/composite_flow_patterns|Prefect Patterns for Subflows!> (:warning: Advanced patterns)

Accredible credential granting: <https://www.notion.so/prefect/Sending-credentials-badges-d66a7fd177e64566a8245e6648c183e3#5972d706a38f41578c2c366a38d20474>