I have to compare two files in aws s3 bucket and generate a new file with only the difference.
I have tried to do using Java, NodeJs and Python, but i couldn't find way to do that.For example we have some libraries in nodejs and python, but it requires input as 'path', but when you retrieve from s3 bucket its coming in different format.
Your AWS Lambda function could:
Download the two files to /tmp/
Use the difflib — Helpers for computing deltas module to find differences
Save the results to a file in /tmp/
Upload the results file to Amazon S3
Delete temporary files that were generated (in case the container is reused, since there is a 500MB limit in /tmp/)
Related
I Have a bucket with 3 million objects. I Even don't know how many folders are there in my S3 bucket and even don't know the names of folders in my bucket.I want to show only list of folders of AWS s3. Is there any way to get list of all folders ?
I would use AWS CLI for this. To get started - have a look here.
Then it is a matter of almost standard linux commands (ls):
aws s3 ls s3://<bucket_name>/path/to/search/folder/ --recursive | grep '/$' > folders.txt
where:
grep command just reads what aws s3 ls command has returned and searches for entries with ending /.
ending > folders.txt saves output to a file.
Note: grep (if I'm not wrong) is unix only utility command. But I believe, you can achieve this on windows as well.
Note 2: depending on the number of files there this operation might (will) take a while.
Note 3: usually in systems like AWS S3, term folder is there only for user to maintain visual similarity with standard file systems however inside it does treat it as a part of a key. You can see in your (web) console when you filter by "prefix".
Amazon S3 buckets with large quantities of objects are very difficult to use. The API calls that list bucket contents are limited to returning 1000 objects per API call. While it is possible to request 'folders' (by using Delimiter='/' and looking at CommonPrefixes), this would take repeated calls to obtain the hierarchy.
Instead, I would recommend using Amazon S3 Inventory, which can provide a daily or weekly CSV file listing all objects. You can then play with that CSV file from code (or possibly Excel? Might be too big?) to obtain your desired listings.
Just be aware that doing anything on that bucket will not be fast.
I have an Amazon S3 server filled with multiple buckets, each bucket containing multiple subfolders. There are easily 50,000 files in total. I need to generate an excel sheet that contains the path/url of each file in each bucket.
For eg, If I have a bucket called b1, and it has a file called f1.txt, I want to be able to export the path of f1 as b1/f1.txt.
This needs to be done for every one of the 50,000 files.
I have tried using S3 browsers like Expandrive and Cyberduck, however they require you to select each and every file to copy their urls.
I also tried exploring the boto3 library in python, however I did not come across any in built functions to get the file urls.
I am looking for any tool I can use, or even a script I can execute to get all the urls. Thanks.
Do you have access to the aws cli? aws s3 ls --recursive {bucket} will list all nested files in a bucket.
Eg this bash command will list all buckets, then recursively print all files in each bucket:
aws s3 ls | while read x y bucket; do aws s3 ls --recursive $bucket | while read x y z path; do echo $path; done; done
(the 'read's are just to strip off uninteresting columns).
nb I'm using v1 CLI.
What you should do is have a look again at boto3 documentation as it is what you are looking for. It is fairly simple to do what you are asking but may take you a bit of reading if you are new to it. Since there is multiple steps involved I will try to steer you in the right direction.
In boto3 for S3 the method you are looking for is list_objects_v2(). This will give you the 'Key' or object path of every object. You will notice that it will return the entire json blob for each object. Since you only are interested in the Key, you can target this just the same way you would access Key/Values in a dict. E.g. list_objects_v2()['Contents'][0]['Key'] should return only object path of the very first object.
If you've got that working the next step is to try to loop and get all values. You can either use a for loop to do this or there is an awesome python package I regularly use called jmespath - https://jmespath.org/
Here is how you can retrieve all object paths up to 1000 objects in one line.
import jmespath
bucket_name='im-a-bucket'
s3_client = boto3.client('s3')
bucket_object_paths = jmespath.search('Contents[*].Key', s3_client.list_objects_v2(Bucket=bucket_name))
Now since your buckets may have more than 1000 objects, you will need to use the paginator to do this. Have a look at this to understand it.
How to get more than 1000 objects from S3 by using list_objects_v2?
Basically the way it works is only 1000 objects can be returned. To overcome this we use a paginator which allows you to return the entire result and treats the limit of 1000 as a pagination so you just need to also use it within a for loop to get all the results you are looking for.
Once you get this working for one bucket, store the result in a variable which will be of type list and repeat for the rest of the buckets. Once you have all this data you could easily just copy paste it into an excel sheet or use python to do it. (Haven't tested the code snippets but they should work).
Amazon s3 inventory can help you with this use case.
Do evaluate that option. refer: https://docs.aws.amazon.com/AmazonS3/latest/userguide/storage-inventory.html
I have a TB sized S3 bucket with pdf files. I need to migrate the old files to glacier. I know that I can create a life cycle rule to migrate files which are older than certain number of days. But in my case currently the bucket consists of both old and new pdf files and they were added at a same time. So they may have same uploaded date. In this case a life cycle rule won't be useful.
In the pdf files there is a field called capture_date. So i need to migrate those files based on the capture_date. (ie: migrate all pdf files if the capture_date < 2015-05-21 likewise).
Will a Fargate job will be useful here? if so, please give a brief idea.
Please suggest your ideas. Thanks in advance
S3 by itself will not read your pdf files. Thus you have to read them yourself, extract data that determine which ones are old and new, and using AWS SDK (or CLI) to move them to Glacier.
Since the files are not too big, you could use S3 Batch along with lambda function which would do the change of the class to glacier.
Alternatively, you could do this on an EC2 instance, using S3 Inventory's CSV list of your objects (assuming large number of them).
And the most traditional way is to just list your bucket, and iterate over each object.
I know this is possible with other sdks (boto, js sdk) but I have no idea how to do it with Powershell (can't find a -Range param).
How do I specify a range when getting an S3 Object with AWS tools?
I have a bucket containing 60k files and some of them (zip files) are corrupted and I know the missing byte is always at the end. So I'd like to check the zip signature in all those files without downloading it in its entirety.
Is it possible with PS? Or should I just use the JS SDK?
I have a large bucket folder with over 30 million object (images). Now, I need to download only 700,000 object (image) from that large folder.
I have the names of objects (images) that I need to download in a .txt file.
I can use AWS CLI, but not sure if it support downloading many objects at one command.
Is there a straight forward solution for that you would have in mind?