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In this video, we are going to learn a lot of the context object in Node.js functions.

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When lambda runs our function, it passes a context object to the handle method.

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This object provides methods and properties that provide information about the invocation, function

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and execution environment.

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You can see any lambda function code.

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The second parameter is the context object.

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You can see in the picture.

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The second parameter is context object that we can use some methods and parameters.

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So context methods, a context object has methods and parameters about the function, invocation function

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itself and execution environment.

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For example, there is the context method.

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Which name is gate remaining time in millis.

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This is returns the number of milliseconds left before the execution time loss.

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And we have some context properties, which is the function name, the function of the name of the lambda

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function and function version, the version of the function.

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So these kinds of information can be accessible from the context object.

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So now we are going to develop an example lambda function to see context objects and parameters into

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the lambda function.

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So let's get started.

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In order to do that, please create a new lecture folder and add the command text file and we will follow

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these for step one performing this example.

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So basically we are going to create a new lambda function and we will start with developing this function

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for that purpose.

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I'm going to create an index that JS file and under the index case file we will follow this example.

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In this example, as you can see that this is a similar handed method, but this time we are going to

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get second parameter, which is the context.

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So event comma, context, object, this will be the lambda function.

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And in this context object we basically lock some of the information, for example, remaining time

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out of the milliseconds.

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We are using the get remaining timeout in milliseconds and also we can get the function name in here.

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Basically we will lock this function name and remaining time in here and return back this information

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to the body of this lambda function.

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Please write this function and we will create this function into our environment.

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So if you come to the comma section, the second step is zip function code.

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In order to do that, I am going to use compress archive command because we have only indexes.

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Please open a new terminal and go to.

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Lecture.

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Now I'm going to compress archive or index JS.

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This will be a great function zip file.

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And the third step is create lambda function with using the sail command.

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If you scroll down, you can see the third step.

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In order to perform create a new function, we should get the function role which is the Lambda X.

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Aaron Please get this Aaron name and after that we are going to create function with using the lambda

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create function select command.

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So in order to do that, I'm going to copy and paste this command.

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This command will be create a new function.

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Which name is my function?

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Three.

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Runtime will be Node.js.

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Zip file which we have a zip in the last step and handle is index and the run name will be the lambda

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x, which we create in the beginning of this section.

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Hit the enter and create this function.

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It is created successfully and now it is time to invoke this function with following the same steps.

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So I'm going to create a JSON file.

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You can see in here.

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Let me create a new file.

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Jason file this will be the our main.

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Don't object that we will pass one invoking our lambda function.

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Okay.

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Now I'm going to invoke our lambda function, which is the my function theory.

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In order to do that, please complete this response and create your window and copy this command, which

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is the lambda IMO command.

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This will be the invoke or a the synchronously function name is my function three and payload is even

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adjacent file that we passed in this file.

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Okay.

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Please hit the enter and invoke our function.

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So as you can see that we get success response.

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If you see the response JSON object.

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You can see the details of the context object parameter.

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The first parameter is function name.

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Function name is my function three and log it to name.

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You can see the log setter name in here.

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If you also compare this log system from the lambda functions, you can see lambda functions and see

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that our newly created function is in here.

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If you go to monitor and V cloud watch logs, you can see the log system name comes in here.

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This is the same name.

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What we have seen in the our response object.

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And if you see like to see the details, you can see the logs about the context remaining time and also

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function name and so on.

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So we can see all these context object details into documentation.

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If you scroll down the C command text, you can see in here, this is the all context properties from

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official documentation.

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You can see that function name version invoked function Aaron Memory limit, log group name, log system,

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name, identity, client context and so on.

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This is the official documentation about the context object.

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Okay.

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As you can see that we have seen how we can use a lambda context object in the Node.js functions.