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  1. Asked: September 15, 2022In:

    How to Copy Files and Directories in Linux

    hari

    How to Copy Files and Directories in Linux Copying files and directories is one of the most common tasks you’ll perform when working on the command line. There are several commands for copying files in Linux, with cp and rsync being the most widely used tools. Copying Files with the cp Command: TheRead more

    How to Copy Files and Directories in Linux

    Copying files and directories is one of the most common tasks you’ll perform when working on the command line. There are several commands for copying files in Linux, with cp and rsync being the most widely used tools.

    Copying Files with the cp Command:

    The most simple use case is to copy a file in the current working directory. For example, to copy a file named file.txt to a file named file_backup.txt in the current directory , you would run the following command:

    cp file.txt file_backup.txtIf the destination file exists, it will be overwritten. To get a confirmation prompt before overwriting the files, use the -i option.

    Copy a file to a directory:

    To copy a file to a directory, specify the absolute or the relative path to the directory

    cp file.txt /backup

    Copy multiple files:

    To copy multiple files and directories at once, specify the names of source files and directories followed with the destination directory as the last argument:

    cp file.txt dir file1.txt file2.txt dir1

    Copying Directories with cp Command:

    To copy a directory, including all its files and subdirectories, use the -R or -r option. In the following example, we are copying the directory Pictures to Pictures_backup:

    cp -R Pictures Pictures_backup

    Copying Files and Directories with the rsync Command:

    rsync -a file.txt file_backup.txt
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  2. Asked: September 15, 2022In:

    Max retries exceeded with URL in requests

    hari
    This answer was edited.

    Max retries exceeded with URL in requests Just use requests features: import requests from requests.adapters import HTTPAdapter from urllib3.util.retry import Retry session = requests.Session() retry = Retry(connect=3, backoff_factor=0.5) adapter = HTTPAdapter(max_retries=retry) session.mount('http:Read more

    Max retries exceeded with URL in requests

    Just use requests features:

    import requests
from requests.adapters import HTTPAdapter
from urllib3.util.retry import Retry
session = requests.Session()
retry = Retry(connect=3, backoff_factor=0.5)
adapter = HTTPAdapter(max_retries=retry)
session.mount('http://', adapter)
session.mount('https://', adapter)
session.get(url)

    This will GET the URL and retry 3 times in case of requests.exceptions.ConnectionError. backoff_factor will help to apply delays between attempts to avoid to fail again in case of periodic request quota.

    Take a look at urllib3.util.retry.Retry, it has many options to simplify retries.

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  3. Asked: September 15, 2022In:

    An error occurred (404) when calling the HeadObject operation: Not Found

    hari

    An error occurred (404) when calling the HeadObject operation: Not Found: I had the same issue recently. You are probably misspelling the path and folder name. In my case, for example, I was messing up with the '/'. To fix it, make sure the variables you are using as arguments for the function contaRead more

    An error occurred (404) when calling the HeadObject operation: Not Found:

    I had the same issue recently. You are probably misspelling the path and folder name. In my case, for example, I was messing up with the ‘/’.

    To fix it, make sure the variables you are using as arguments for the function contains the correct names of the directories, folders and files as it is in S3. Also, make sure you put the ‘/’ in the correct places in the correct variables. For instance, in my case I found that:

    • bucket name: bucket_name (with no ‘/’ in the end, and no ‘s3://’)
    • directory name: folder1/folder2/file_name (with no ‘/’ in the beginning)

    I hope it helps you and others to get around this error easily.

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  4. Asked: September 4, 2022In:

    How to Turn on the Backlit Keyboard on a Dell

    hari

    DELL offers a backlit keyboard in its Laptop/Notebook which is an optional feature. But unlike Apple MacBook Pro, there is no sensor that can automatically turn on the backlit keyboard in dim light. Instead, you need to manually enable the backlit keyboard if you have it on your device. See how to dRead more

    DELL offers a backlit keyboard in its Laptop/Notebook which is an optional feature. But unlike Apple MacBook Pro, there is no sensor that can automatically turn on the backlit keyboard in dim light. Instead, you need to manually enable the backlit keyboard if you have it on your device. See how to do that –

    This could be a simple F5, F9, or F11 key press, or a dual-action Fn + F5, F9, or F11 key press.

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  5. Asked: August 17, 2022In:

    How can I validate an email address in JavaScript?

    hari
    This answer was edited.

    Email validation in javascript: var regexEmail = /\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*/; var email = document.getElementById("txtEmail"); if (regexEmail.test(email.value)) { alert("It's Okay") } else { alert("Not Okay") }

    Email validation in javascript:

    var regexEmail = /\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*/;
var email = document.getElementById("txtEmail");
if (regexEmail.test(email.value)) {
    alert("It's Okay")
} else {
    alert("Not Okay")
}
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  6. Asked: July 21, 2022In:

    How do I revert a Git repository to a previous commit?

    hari

    Revert back without keeping the changes: git reset --hard <commit> Revert back with keeping the changes: git reset --soft <commit> Explanation: using git reset, you can reset to a specific state. It's common using it with a commit hash as you see above. But as you see the difference is uRead more

    Revert back without keeping the changes:

    git reset --hard <commit>

    Revert back with keeping the changes:

    git reset --soft <commit>

    Explanation: using git reset, you can reset to a specific state. It’s common using it with a commit hash as you see above.

    But as you see the difference is using the two flags --soft and --hard, by default git reset using --soft flag, but it’s a good practice always using the flag, I explain each flag:

    –soft

    The default flag as explained, not need to provide it, does not change the working tree, but it adds all changed files ready to commit, so you go back to the commit status which changes to files get unstaged.

    –hard

    Be careful with this flag. It resets the working tree and all changes to tracked files and all will be gone!

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  7. Asked: July 21, 2022In:

    Git checkout another branch

    hari

    Creates a new local branch and directly switches to it. git checkout -b new-branch

    Creates a new local branch and directly switches to it.

    git checkout -b new-branch

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  8. Asked: March 3, 2022In:

    How do I find Apache http server log files?

    hari
    This answer was edited.

    Apache logs are files that record everything the Apache web server is doing for later analysis by the server administrator. The records of all Apache events are placed in two different text files: Access Log: this file stores information about incoming requests. You'll find details about each requesRead more

    Apache logs are files that record everything the Apache web server is doing for later analysis by the server administrator. The records of all Apache events are placed in two different text files:

    • Access Log: this file stores information about incoming requests. You’ll find details about each request such as the requested resource, response codes, time taken to generate the response, IP address of the client, and more.
    • Error Log: this file contains diagnostic information about any errors were encountered while processing requests.

    The log files’ location depends on the operating system the Apache web server is running. On Debian-based operating systems like Ubuntu, the access log file is located in /var/log/apache2/access.log. On CentOS, RHEL, or Fedora, the access log file is stored in /var/log/httpd/access_log.

    Similarly, the error log file is located in /var/log/apache2/error.log on Debian-based systems and /var/log/httpd/error_log on CentOS, RHEL, or Fedora. A typical error log entry might look like this:

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  9. Asked: February 17, 2022In:

    Is it really necessary for a programmer to learn data structures and algorithms?

    hari

    Yes, it is important because Data Structure and Algorithm (DSA) provide techniques to programmers to manage data. Data Structure means organizing, storing and processing Data. Whereas Algorithms means a series of steps that are followed in sequence to solve a particular problem.

    Yes, it is important because Data Structure and Algorithm (DSA) provide techniques to programmers to manage data. Data Structure means organizing, storing and processing Data. Whereas Algorithms means a series of steps that are followed in sequence to solve a particular problem.

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  10. Asked: August 31, 2021In:

    download files from s3 given the file path using boto3 in python

    hari

    def get_download_link_logs(dayfile): s3_link = config.s3_file_link + "logs/%s" % dayfile print(s3_link) s3_file_link: Bucket Path dayfile: filename

    def get_download_link_logs(dayfile):
    s3_link = config.s3_file_link + "logs/%s" % dayfile
    print(s3_link)

s3_file_link: Bucket Path
dayfile: filename
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