How Do You Find You out the AWS Instance ID from inside the OS of a Server?

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Problem scenario
You are using AWS via web browser while using multiple Putty sessions are you logged into several AWS servers (aka AWS instances).  You can find the host names and internal IP addresses of the servers when you are logged into via the command line of the OS itself.  From the AWS console you can find external IP addresses and external FQDNs.  You do not know how to correlate these instances (as the information readily available in Putty at the OS level is independent of the information available via the AWS console).

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How Do You Troubleshoot Weebly Blog Editor Not Updating Posts after You Make Changes to Them?

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Problem scenario
You are using Weebly website editor. You make changes to a post, then click “Update.”  You then click “Publish.”  But the changes to your website are not updating.  What do you do?

Solution
Log out of the Weebly editor.  Close all of the instances of the web browser you were using.  Then reopen the web browser.  Clear the cache,

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How Do You Connect to a Specific Database in Postgres Using PHP?

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Problem scenario
Using PHP you want to connect to a specific database to run SQL queries.  How do you do this?

Solution
Assuming you have installed PHP and Postgres on the same Ubuntu Linux server, install the php-pgsql package.  Follow this link if you need assistance.  

1.  Create a file like this named contint.php:

<?php
   $host  

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How Do You Create a Web Page That Issues Customized SQL Commands to a Database Behind-The-Scenes?

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Problem scenario
You want a web page with a text field to enter a single line of SQL code.  You want this code (as opposed to some fixed, pre-written code) to execute.  How do you do this?

Solution
This is more dangerous because SQL injection attacks are a serious problem.  This link is how to have a PHP page execute fixed code.

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How Can You Accept User Input with PHP and Use It in a SQL Command?

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Problem scenario
You want to read in user input via a web page.  You then want that user input to participate in an invocation of a SQL command. How do you get user input to be a variable in the construction of a SQL command that is automatically executed when a web-page button is clicked?

Solution
Warning
This does not prevent against SQL injection attacks.

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How Do You Get a Web Page to Invoke a Postgres Command (e.g., for a RESTful API)?

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Problem scenario
You want a REST call to invoke some SQL code on a Postgres database.  How do you do this?

Solution
Install Apache web server, PHP, and the PHP-pgsql package on your Postgresql database server.  This example assumes you have PHP, Apache web server, Postgres, and the php-pgsql package installed on your server.  Assuming the web server is running and the default directory for web pages is still /var/www/html/ do the following.

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List of Flask (Web-Framework) Books

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Beginning Web Development with Python: from prototype to production with flask, tornado and nginx by Andrei Dan
Building Web Applications with Flask by Italo Maia
Data Visualization with Python and JavaScript: Scrape, Clean, Explore & Transform Your Data by Kyran Dale  
Flask Blueprints by Joel Perras
Flask By Example by Gareth Dwyer
Flask Framework Cookbook by Shalabh Aggarwal
Flask Web Development: Developing Web Applications with Python by Miguel Grinberg
Instant Flask Web Development by Ron DuPlain
Learning Flask Framework by Matt Copperwaite and Charles Leifer
Mastering Flask by Jack Stouffer
Python in 24 Hours,

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