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. Inspect

    The HTML source is shown below: Inspect

    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: smtp

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

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

Configure SysUpTime

  1. Add a web site monitor: add 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

  2. Press “Configure” button next to the “Threshold settings”. add monitor Move “body response time” to the left and move “content match” to the right panel.

  3. 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. add monitor

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

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

  5. In the following screen add monitor Press “Configure” button next to the “Actions”

  6. Enter your email address to receive email notification when price drops below threshold: add monitor

  7. Press “Ok” buttons to save the monitor.

  8. (Optional) In the “Manage Monitor” dialog, select the newly created monitor and press “Chart” button to see the real time chart. graph