Video 3.4 learning cloud watch events. In this video, we will learn the following. What are cloud watch events? Why are they using cloud watch events, creating an event testing event? What are cloud watch events? Amazing cloud watch events enables you to create a set of rules that you can match with certain events.

You can also route these events to one or more targets like lambda functions, amazing SNS topics, amazing Sq s cues and other target types. Whenever there are operational changes in the AWS environment, cloud watch events responds to these changes and performs corrective actions by sending messages or notifications, activating functions, etc. You can also use the cloud watch events to shedule automated actions that self triggered at certain times using cron or ratings. permissions. Before getting started with cloud watch events. Let's take an overview of events, targets and rules.

What are events, any change in the AWS environment can be an event. AWS resources generate events when they state changes. Amazon allows us to generate two types of events. First type, we can set up sheduled events that are generated on a periodic basis. Second type, we can create our own custom application level events and publish them to cloud watch events. What are targets a target processes the above events.

Targets can include Amazon SNS topics, Amazon Sq s queues, AWS lambda functions, kinases streams and built in targets. A target receives events in JSON format. In our project, the target will be an Sq sq. What are rules, a rule matches all incoming events and directs them to targets for processing. A single rule can route to multiple targets, all of which are processed in parallel. Rules are not processed in a particular order.

So this enables you to process events in some particular order based on our interests. Bringing all these together, we will create a cloud watch event. In our project, we will schedule a trigger. Okay. To be more clear, we will use Cloud watch events to shedule a message to SQL is at 10am every day using cron expression. For better understanding, let's start creating an event.

Log into your AWS account in the AWS Management Console, search for cloud watch selected. Now here on the left hand side, choose events get started. Tip one, create a rule. In event source. You can either build an event pattern, or should you learn event. In our project, we will be scheduling an event.

So select shedule. Here, you can select either a fixed rate or a cron expression. Since we want to schedule an event every day at 10am. I will choose cron expression. Now giving the cron expression Okay, let me explain the basics of a cron expression. Basically, a cron expression has six fields where each field is separated by whitespace.

The six fields include minutes, hours, which day of the month, month, which day of the week, and ear. These are the minimum and maximum values that each field can have. Now, let's take a look at the wildcards. Comma, it means additional value To use. For example, if you want to share during an event only on Sunday, Monday and Tuesday, then you can give one comma two comma three in the day field, then it would shedule events only on Sunday, Monday and Tuesday dash, this specifies a particular range. For example, you can give one dash three in the above example, forward slash, this means increment.

For example, in the minutes field, you can give zero forward slash 15. This means for every 15 minutes, asterisk, this means all values in the field. If I give asterisk in the day of the week field, then it includes all the days in the week, simply it means every day. Remember, we cannot use asterisk in both the day of month and day of week fields. If you want to use asterisk in both the fields, then you can use an asterisk For one field and a question mark for another field, so I gave the cron expression as zero 10 asterisk asterisk, question mark, asterisk. Zero indicates minutes.

10 Indicates us so 10am the asterisk here indicates everyday of a month. Next, this asterisk indicates month, that is every month, day of the week. Since we have already used an asterisk for the day of the month, here, I gave a question mark, which means all the days in the week, next year. Here again, I give an asterisk, which means every year, so the value for my cron expression is 10am every day, actually, Amazon will show you the time at which the next 10 triggers will occur. So this will help you in verifying the cron expression. Okay, now let's quickly set the target on the right hand side in Goods choose at Target.

For our project, we will choose the Sq Sq here. Now select the queue we created in the previous video. Choose configure details. Now we can give a name and description here. I will give my rule name as my ESP 32 underscore cloud watch and description as trigger excuse every day at 10am. Finally, selecting create rule.

The rule has been successfully created. Yes, now let's check Sq s at 10am and see if there is any message open Sq s and select the queue that we have created in the previous video. Now, here on the top, choose queue actions, then view or delete messages. Start polling for messages. If everything is correct, you can see a random message at 10am this message will be stored temporarily for four days here in this queue. Now, I will end this video here.

In this video, we learned the following. What are cloud watch events? Why are we using cloud watch events, creating an event testing. In the next video, we will demonstrate sheduled get triggered