How to access newly added file in S3 bucket using python - amazon-web-services

I am new to aws I access files in S3 using python I need to access newly added files in the bucket. Instead of accessing every data present in the bucket. Can anyone help me to reslove this issue?. Thank you

Take a look at S3 event notifications. You can have all new files be sent to an SQS queue and have your python program read from the queue to get new files. There is not a way to query S3 for new files. Or if you could create a lambda function to operate on new files as well depending on what you need to do with new files.

You can create a lambda with your business logic in python and finally you create an event in s3:
Enter S3 bucket
Select "Properties" tab
Advance settign section -> Events
New Event:
Important: You must have the lambda created.
Diagram:

Related

How to Trigger codepipeline with s3 with dynamic s3 object key?

I have a bucket whose objects have commitId as their name. I want to pass these commitID to my codepipeline and utilise those id for slack messages.
I am trying to trigger Codepipeline when a zip file is uploaded to s3, however as I can see in the documents, it can only trigger with a static bucket key. I want to trigger with any file name
https://docs.aws.amazon.com/codepipeline/latest/userguide/action-reference-S3.html
I am dealing with a use case where the uploaded object in s3 will have dynamic object keys.
How to deal with this situation?
I have read this question so I know using s3 with lambda and then trigger pipeline with lambda but this will still not work because I need to pass zip file to codebuild
TL;DR Have the Lambda record the ID in commit_id.txt and add it to the bundle.
I understand you want to execute a pipeline when an arbitrary object, say a5bf8c1.zip is added to a S3 path, say MyPipelineBucket/commits/. The pipeline has a S3 source, say MyPipelineBucket/source.zip. Your pipeline executions also require the file name value (a5bf8c1).
Set up S3 Event Notifications on the bucket. Apply object key name filtering on the MyPipelineBucket/commits/ prefix.
Set a Lambda Function as the destination
The Lambda receives the Commit ID in the event notification payload as the triggering file name. Write it to commit_id.txt file. Using the SDK, get the MyPipelineBucket/commits/a5bf8c1.zip bundle from S3. Add commit_id.txt to the bundle. Put the new bundle to MyPipelineBucket/source.zip. This will trigger an execution.
In your pipeline, your CodeBuild commands now have access to the Commit ID. For instance, you can set the Commit ID as an environment variable:
COMMIT_ID=$(cat commit_id.txt)
echo COMMIT_ID # -> a5bf8c1

How to set up directory level triggers in AWS S3 for Lambda?

I have a directory structure as shown below
S3 Bucket
-logs/
-product1_log.txt
-product2_log.txt
-images/
-products/
There are a couple of directories mentioned above in the S3 bucket, now whenever a new file gets added to the logs folder, I have a lambda function that updates the timestamp in my MongoDB.
Requirement
Trigger lambda function only when logs folder gets updated, update to other folders should not trigger the lambda
Exact same use case described in the below link.
https://docs.aws.amazon.com/AmazonS3/latest/userguide/notification-how-to-filtering.html

Aws s3 trigger lambda on new files that are NOT temporary files

i want to launch a lambda for any new complete file, the process is quite simple:
i upload files to s3
for every new files in the directory I launch a lambda
unfortunately, i see that my lambdas invokes on _temporary/* files, which are files that are not fully uploaded to s3. what can i do?
thanks!
There is no concept of a "partially uploaded" file in Amazon S3. Either the whole object is created, or the object is not created. Nor does Amazon S3 have a concept of "temporary" or _temporary/ files. If they exist, it is because your application is uploading those files.
When creating an Amazon S3 event, you can specify a Prefix. The event will only be triggered for objects matching that prefix.
Alternatively, you could add a line of code at the start of the AWS Lambda function that checks the Key of the object and exits if it does not need to perform any actions on the object.

Parse data from aws s3 bucket and save parsed data to another bucket

I'm new to AWS S3, and I was reading to this tutorial from AWS on how to move data from bucket to another
How can I copy objects between Amazon S3 buckets?
However, I didn't notice, or it didn't mention that you can apply a hook or any intermediate step before data will be saved.
Ideally, we wanted to take the data from a log bucket(its very dirty and wanted to clean it up a bit) and save another copy of it in another S3 (the parsed data). We also wanted to do this periodically so that automation would be necessary for the future.
What I wanted to know is that, can I do this with just S3 or do I need to use another service to do the parsing and saving to another bucket.
Any insight is appreciated, thanks!
S3 by itself is simply for storage. You should be looking at using AWS Lambda with Amazon S3.
Every time a file is pushed to your Log bucket, S3 can trigger a Lambda function (that you write) that can read the file, do the clean up, and then push the cleaned data to the new S3 bucket.
Hope this helps.

Does AWS S3 Have a concept of files being 'updated'?

I'd like to write a Lambda function that is triggered when files are added or modified in an s3 bucket and processes them and moves them elsewhere, clobbering older versions of the files.
I'm wondering if AWS Lambda can be configured to trigger when files are updated?
After reviewing the Boto3 documentation for s3 it looks like the only things that could happen in a s3 bucket would be creations and deletions.
Additionally, the AWS documentation seems to indicate there is no way to trigger things on 'updates' to S3.
Am I correct in thinking there is no real concept of an 'update' to a file in S3 and that an update would actually be when something was destroyed and recreated? If I'm mistaken, how can I trigger a Lambda function when an S3 file is changed in a bucket?
No, there is no concept of updating a file on S3. A file on S3 is updated the same way it is uploaded in the first place - through a PUT object request. (Relevant answer here.) An S3 bucket notification configured to trigger on a PUT object request can execute a Lambda function.
There is now a new functionality for S3 buckets. Under properties there is the possibility to enable versioning for this bucket. And if you set a trigger for creating on S3 assigned to your Lambda function - this will executed every time if you 'update' the same file as it is a new version.