What is meaning of 'can only concatenate str (not "int") to str?'-CodePudding

I want to call 70 threads in my code as you can see to get html content :

def run_the_command(args):
    conn = pyodbc.connect(
        "Driver={SQL Server};"
        "Server=.;"
        "Database=test;"
        "Trusted_Connection=yes;"
    )
    r = requests.get("https://coinmarketcap.com/?page="   args)
    soup = BeautifulSoup(r.text, "lxml")

    table = soup.find("table", class_="cmc-table")
    for row in table.tbody.find_all("tr"):
        # Find all data for each column
        columns = row.find_all("td")
        link = "https://coinmarketcap.com"   columns[2].a["href"]

        r2 = requests.get(link)
        soup2 = BeautifulSoup(r2.text, "lxml")
        cursor = conn.cursor()

        sql = "insert into coins(price,submitdate,name) values(?,?,?)"

        val = [
            (
                soup2.select_one('[class^="priceValue"]').text,
                datetime.today().strftime("%Y-%m-%d"),
                link,
            )
        ]

        cursor.executemany(sql, val)

        conn.commit()


try:

    if __name__ == "__main__":
        threads = []
        for i in range(70):
            t = threading.Thread(target=run_the_command, args=(i   1,))
            t.start()
            threads.append(t)

except requests.exceptions.RequestException as e:
    print(e)

But I get this error :

    self._target(*self._args, **self._kwargs)
    self._target(*self._args, **self._kwargs)
  File "c:\Users\e.akbar\Desktop\Crypto\gettable.py", line 14, in run_the_command
  File "c:\Users\e.akbar\Desktop\Crypto\gettable.py", line 14, in run_the_command
  File "c:\Users\e.akbar\Desktop\Crypto\gettable.py", line 14, in run_the_command
    r = requests.get('https://coinmarketcap.com/?page=' args)
TypeError: can only concatenate str (not "int") to str
    r = requests.get('https://coinmarketcap.com/?page=' args)
TypeError: can only concatenate str (not "int") to str
    r = requests.get('https://coinmarketcap.com/?page=' args)
    r = requests.get('https://coinmarketcap.com/?page=' args)
TypeError: can only concatenate str (not "int") to str
    r = requests.get('https://coinmarketcap.com/?page=' args)
TypeError: can only concatenate str (not "int") to str
TypeError: can only concatenate str (not "int") to str

I am new in python

CodePudding user response：

You would get the same error without multithreading if you call run_the_command(1).

You're attempting to use to concatenate a string and a number; you could either cast the number to a string with str(), or more modernly use an f-string to format it into your URL:

r = requests.get(f'https://coinmarketcap.com/?page={args}')

However, better yet, since you're using Requests, just use its parameter handling:

r = requests.get('https://coinmarketcap.com/', params={'page': args})

As an aside:

you'll probably want to look into multiprocessing – starting 70 threads will likely not give you an appreciable performance boost due to the GIL.
you might want to use Coinmarketcap's API instead of trying to scrape things. https://coinmarketcap.com/api/

CodePudding user response：

Your issue is not related to threading. You are trying to concatenate the string with int. Try change:

r = requests.get('https://coinmarketcap.com/?page=' args)

To:

r = requests.get('https://coinmarketcap.com/?page=' str(args))