Invoke AWS Lambda Function From Another Lambda | Step by Step Tutorial

[@BeABetterDev]

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[@shogunrage]

Dude! This video saved me hours of headache, you are the best!!!

[@pfkong6917]

Your lessons are always clear! Thanks.

[@BeABetterDev]

Glad you think so!

[@adityanjsg99]

So much awesomeness!! And absolutely free!

[@BeABetterDev]

Glad this could help

[@sunhoyou]

Simple and precise. So much thanks!

[@BeABetterDev]

Glad it was helpful!

[@anjandey6089]

@@BeABetterDev can you share the policyrole for invokerlambda

[@fabtjar]

Would have been good for you to discuss why you would need to invoke another function inside this one and the pros/cons of it. Is it an antipattern?

[@flaringphoenix7725]

If we can do this directly, what is the use of a step function?

[@krishnajunk]

Your videos are simple and very clear. Thanks

[@BeABetterDev]

Glad you like them!

[@RuwanIndikaPrasanna]

Thanks, great tutorial

[@BeABetterDev]

You're very welcome Ruwan!

[@jiweihe3413]

thanks for the explanation. it is very clear. Is it possible to pass query parameters in URL from the invoker lambda to the invoked lambda?

[@BeABetterDev]

Hi Jiwei, it certainly is!

[@bigworldparty]

Clear and useful tutorial. I'm wondering what is the reason for doing this sort of RequestResponse invoke, rather than instead hitting the URL endpoint of the second function? The application at my company, seems to use HTTP endpoints (like you might hit using Postman) for all the lambda connectivity.

[@tibistibi]

how would this work when you want to make use of a peering VPC connection and maybe and lambda endpoint setup?

[@leonardoflores2974]

Excelent video thanks

[@BeABetterDev]

You're very welcome Leonardo!

[@jimbrannlund4677]

Great video! But! Why do you need the InvokeAsync permission when you're not calling the LambdaToInvoke asynchronously? FWIW I have a similar setup where I DO call the other lambda async and it works without that permission.

[@BeABetterDev]

Good callout Jim. If I recall correctly you may only need the LambdaBasicExecution role to get this working for sync requests. I was showing the Async permission for completion sake. Cheers.

[@mouneydonuru2769]

Just a small doubt, are handlers and lambda functions the same?

[@veenadevivenu2175]

Can you make the video about adding layers with AWS lambda C++ runtime..

[@errolm8313]

I'm getting an error: "errorMessage": "2020-11-04T00:54:40.357Z b7d36488-ab6e-4530-a91f-d3d6a2fe72a5 Task timed out after 3.09 seconds" what does this mean?

[@primetimephoenix81]

@AWS Simplified I have another question, what would be the best way to execute a java jar file in aws lambda running a python runtime?

[@BeABetterDev]

Hi Sanket. Where is the JAR located? It first needs to be downloaded and placed on the fs. From there, you can execute jars using something like this: stackoverflow.com/questions/7372592/python-how-can-i-execute-a-jar-file-through-a-python-script

[@primetimephoenix81]

@@BeABetterDev I download it and place it in /tmp folder of the lambda. Then I used to use subprocess.check_output would subprocess.call be better? Am I supposed to download it to a particular location in the lambda's file system? I thought we needed Java runtime for jar execution? Thank you so much for your response!

[@chrismobus4135]

Hey thank you for your videos, which helped me a lot. Can you make a video about Lambda Layers? Modules like Pillow for example are quite tricky, because they don't work properly, if you deploy it on Mac or Windows. You have to deploy it with docker or an EC2-Instance. This problem drives me crazy :D

[@BeABetterDev]

Hey Chris, Thanks for the suggestion! I'll take a look into Lambda Layers and consider putting a video together. Thanks again for your support!

[@primetimephoenix81]

@AWS Simplified I have a quick question: Lambda functions have a time out cap of 15 minutes. Say you choose to accept to return response, and child function takes close to 15 minutes, will the parent function timeout?

[@BeABetterDev]

Hi Sanket, yes it will. In this scenario it may make more sense to invoke the child function asynchronously so that the parent does not have to wait for a completion signal. The main concern with this approach is that the parent loses visibility into whether or not the child succeeds. If your use case can handle this limitation, then I would say async is certainly viable. Hope this helps.

[@primetimephoenix81]

@@BeABetterDev thanks! This helps a lot! Great tutorial! Very well explained! 👍🏾

[@TechTutorETLandAWS]

@@BeABetterDev but how to pass values in asynchronous method from one lambda to other

[@klarusdetro1544]

ich liebe es, bitte mehr

[@BeABetterDev]

danke Klarus!

[@govindsajeev8754]

How can I use a lambda function to create a s3 trigger for another lambda function

[@sourenasahraian2055]

Thanks for this video, is the underlying protocol for boto lib http ? Is the caller effectively issuing a REST request? Can I for instance call Axios to issue a REST request to the callee Lamda function and would that need to go through API gateway?

[@andriys5772]

Thank you!

[@BeABetterDev]

You're welcome!

[@OakZ-sr9by]

I am unable to paste the code when I try to create the policy. When I paste it says JSON syntac error

[@pawankpk8301]

can you post one video same thing via java code

[@sourishdutta9600]

Hi Thank you For your videos, Sir it will be very kind if you help me to understand this concept like, In Pagination How we can store LastEvaluatedKey in previous Lambda call so that we can pass that value in ExclusiveStartKey in the next lambda call when the front end will call for next set of data? I am facing difficulties to achieve and understand the concept so can you please help me to understand this thing and make one video on that. Thank you so much, sir, appreciate your hard work and talent.

[@cheribgh275]

Hellllo! first of all thanks for the awesome explanation, I got a question though, can I use the same method to call a lambda function written in Java? thanks!

[@BeABetterDev]

Hi Shahrzad, Great question. The answer is YES! This is one of the coolest part about Lambdas, it doesn't matter which language they are implemented in - you can use them the same. Hope this helps Daniel

[@MsAneesh007]

Thanks !

[@BeABetterDev]

You are very welcome anish!

[@lucholafrazia5700]

Great video! I have a little question here. I'm facing an issue where I'm generating a report that takes more than 30s so I'm receiving a timeout, due to API Gateway. I've read about async lambdas, but in my case I need the result of the lambda which will generate the report. Basically, the lambda query the data, generates the xls, upload to S3 and return the link to be download from a react app. Do you have any suggestions how to overcome this scenario? Thank you!!

[@BeABetterDev]

Hi Luncho, What you can do is when the initial call is made to the lambda function, generate a UUID that will be the name of the s3 file that gets generated and uploaded. Return that ID back to the caller. The caller can then periodically poll from S3 (or an API that in turn calls S3) to get the data. Hope this helps provide some guidance.

[@lucholafrazia5700]

@@BeABetterDev you’re the best! Really appreciate your input here!!

[@BeABetterDev]

You're very welcome!

[@dinhduongvan4562]

How to pass data to header use runtime java 11?

[@IdlanAmran]

Hi, just want to ask, does Python runtime supports recursive invocations in Lambda ? currently I have a long running web scraper that needs to run for a very long time to finish, thus need more than 15 minutes for time. Sorry for bothering, btw its a great video.

[@akshayshelke765]

thanks

[@BeABetterDev]

You're welcome!

[@ZaferKilicaslan]

Hi very good tutorial. I am trying to implement a fanout but I have no clue how to do that. My lambda function should invoked for eg. 100 customers simultaneously Have you a example for me Thanks in advance 🙏

[@BeABetterDev]

Hi Zafer, What you could do is publish messages for each customer into an SQS queue. Then you can have a lambda function hooked up to the SQS queue as an event source. Each of the messages will be processed in a separate thread very quickly. You can check out one of my other videos on SNS to SQS on my channel to see how this is set up. This video also may be helpful comparing SNS and SQS: kzbin.info/www/bejne/o4nOYYCEn9GCbaM

[@ankitbhatia6128]

You must tell how roles are being handled in these lambda functions.

[@gg8117]

Hey something that is bothering me... in your tutorials its hard to follow the actual important part... writing the code in the lambdas. You seem to skip this a lot. Event vs context? Never explained!

[@grabteawithme2560]

I only know one Invoker :V