Monitor Amazon Price Changes

This article demonstrates how to use the web site monitor to check a product's price on Amazon periodically and send email when price changes.

Amazon Page Info

Let's pick an Amazon Kindle as an example. The shopping URL is

https://www.amazon.com/All-new-Kindle-Oasis-now-with-adjustable-warm-light/dp/B07F81WWKP/ref=sr_1_9?dchild=1

• Use Chrome browser to open the URL. Right click on the price area and select "Inspect" menu.

The HTML source is shown below:

So we can look for a "td" node with "id" being "priceblock_ourprice_lbl", and its text node value is "Price:", and the real price is in the subsequent "span" node with "id" being "priceblock_ourprice".

Configure SMTP server

SMTP server needs to be configured first for sending email on alarm

1. Select "Setting/SMTP Server" menu:
   

2. Enter SMTP server parameters. We use gmail as an example:
   

Then press "Send Test Mail" to check if the SMTP server has been configured successfully.

Configure SysUpTime

• Add a web site monitor:
  
  

  In the URL field, enter
  

  https://www.amazon.com/All-new-Kindle-Oasis-now-with-adjustable-warm-light/dp/B07F81WWKP/ref=sr_1_9?dchild=1

• Press "Configure" button next to the "Threshold settings".

Move "body response time" to the left and move "content match" to the right panel.

• Configure it to use simple content match, and choose "Line contains" radio button, enter.

  engine_daemon_container_states_containers{state="running"}

to the text field of "Line contains". In the token field, enter "2".
The value is the second token of the line.

• In the threshold field, enter 340, so that an alarm will be raised when price drops below 340.

Press "Ok" buttons to go back to the screen at step 1.

• In the following screen

Press "Configure" button next to the "Actions"

• Enter your email address to receive email notification when price drops below threshold:
  
  

• Press "Ok" buttons to save the monitor.

• (Optional) In the "Manage Monitor" dialog, select the newly created monitor and press "Chart" button to see the real time chart.