CSV Importing With Rails, Postgres, and Sidekiq - postgresql

I'm building a customer management system using Rails that requires CSV files containing customer information to be imported into/diffed with a Postgres database. I'm hosting the application on Heroku. I moved the database to the background with Sidekiq but need advice on where to upload the file to in the first place for importing. Is hosting the file on S3 really the best solution or is there a simpler solution without using a third party storage service? The application will be used daily but up 10 employees and the larges CSV file being upload is around 100,000 rows.
Thanks.

Yes, I do think S3 is the best solution
We faced same problem at Storemapper (we use Resque instead of Sidekiq, but that's not a problem). The limiting factor here is the Heroku request timeout. You only have 30s to finish your upload to Heroku, which put hard limit on how big your csv can be. This is where S3 come. Basically what we do is:
User upload csv directly to S3 via javascript, bypassing our app server on Heroku.
Once the upload complete, the javascript makes a request to app server that will launch background worker, telling the worker where the file is at S3
The worker download the csv from s3, then process it as necessary
I found carrierwave_direct gem to be very helpful for step 1 and 2. For step 3, I use smarter_csv gem. Checkout our complete story here:
https://tylertringas.com/very-large-csv-import-in-rails-on-heroku/

Related

Updating online Mongo Database from offline copy

I have a large Mongo database (5M documents). I edit the database from an offline application, so I store the database on my local computer. However, I want to be able to maintain an online copy of the database, so that my website can access it.
How can I update the online copy regularly, without having to upload multiple GBs of data every time?
Is there some way to "track changes" and upload only the diff, like in Git?
Following up on my comment:
Can't you store the commands you used on your offline db, and then
apply them on the online db, through a script running on SSH for
instance ? Or even better upload a file with all the commands you ran
on your offline base, to your server and then execute them with a cron
job, or a bash script ? (The only requirement would be for your bases
to have the same start point, and same state, when you execute the
script)
I would recommend to store all the queries you execute on your offline base, to do this you have many options, I can think about the following : You can set the profiling level to log all your queries.
(Here is a more detailed thread on the matter: MongoDB logging all queries)
Then you would have to extract then somehow (grep ?), or store them directly in another file on the fly, when they are executed.
For the uploading of the script, it depends on what you would like to use, but i suppose you would need to do it during low usage hours, and you could automate the task with a CRON job, and an SSH tunnel.
I guess it all depends on your constraints (security, downtime, etc..)

Upload data to Cloud Storage from external website

I need to upload data from a public source to one of my Cloud Storage buckets. Currently, I download the data to my machine and then upload it to GCS. Being huge data sources (60GB in all, this week), I began running into problems to do it.
Is there a way to do it coding straight into GCS, without needing all the local downloading process?
UPDATE: I have tried using curl http://originaladdress | gsutil cp - gs://bucket. The problem is it would take 21 hours to do the whole process with 100 MB chunks, which is longer than it takes for me to download and upload the file. Is that right? Did I miss some parameter?

How to update files whenever script is scheduled to run in Heroku app

I have a simple python script that is hosted on Heroku and I'm using the Heroku Scheduler to run the script every hour/day. The script will possibly update a simple .txt file (could also be a config var if possible) when it runs. When it does run and conditions are met, I need that value stored and used when the next scheduled script runs. The value changed is simply a date.
However, since the app is containerized based on the most recent code I have on Github, it doesn't store those changes anywhere to be used again. Is there any way I can accomplish to update the file and use it every time it runs? Any simple add-ons or other solutions I can use?
Heroku Dynos have a local file system that does not survive an application restart or redeployment, therefore it cannot be used to persist data.
Typically you have 2 options:
use a database. On Heroku you can use (there is also a Free tier) Postgres
save the file on external storage (S3, Dropbox, even GitHub). See Files on Heroku for details and examples

Is there a way to upload data from FTP server to Amazon S3? [duplicate]

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Is there a way to connect to an Amazon S3 bucket with FTP or SFTP rather than the built-in Amazon file transfer interface in the AWS console? Seems odd that this isn't a readily available option.
There are three options.
You can use a native Amazon Managed SFTP service (aka AWS Transfer for SFTP), which is easier to set up.
Or you can mount the bucket to a file system on a Linux server and access the files using the SFTP as any other files on the server (which gives you greater control).
Or you can just use a (GUI) client that natively supports S3 protocol (what is free).
Managed SFTP Service
In your Amazon AWS Console, go to AWS Transfer for SFTP and create a new server.
In SFTP server page, add a new SFTP user (or users).
Permissions of users are governed by an associated AWS role in IAM service (for a quick start, you can use AmazonS3FullAccess policy).
The role must have a trust relationship to transfer.amazonaws.com.
For details, see my guide Setting up an SFTP access to Amazon S3.
Mounting Bucket to Linux Server
Just mount the bucket using s3fs file system (or similar) to a Linux server (e.g. Amazon EC2) and use the server's built-in SFTP server to access the bucket.
Install the s3fs
Add your security credentials in a form access-key-id:secret-access-key to /etc/passwd-s3fs
Add a bucket mounting entry to fstab:
<bucket> /mnt/<bucket> fuse.s3fs rw,nosuid,nodev,allow_other 0 0
For details, see my guide Setting up an SFTP access to Amazon S3.
Use S3 Client
Or use any free "FTP/SFTP client", that's also an "S3 client", and you do not have setup anything on server-side. For example, my WinSCP or Cyberduck.
WinSCP has even scripting and .NET/PowerShell interface, if you need to automate the transfers.
Update
S3 now offers a fully-managed SFTP Gateway Service for S3 that integrates with IAM and can be administered using aws-cli.
There are theoretical and practical reasons why this isn't a perfect solution, but it does work...
You can install an FTP/SFTP service (such as proftpd) on a linux server, either in EC2 or in your own data center... then mount a bucket into the filesystem where the ftp server is configured to chroot, using s3fs.
I have a client that serves content out of S3, and the content is provided to them by a 3rd party who only supports ftp pushes... so, with some hesitation (due to the impedance mismatch between S3 and an actual filesystem) but lacking the time to write a proper FTP/S3 gateway server software package (which I still intend to do one of these days), I proposed and deployed this solution for them several months ago and they have not reported any problems with the system.
As a bonus, since proftpd can chroot each user into their own home directory and "pretend" (as far as the user can tell) that files owned by the proftpd user are actually owned by the logged in user, this segregates each ftp user into a "subdirectory" of the bucket, and makes the other users' files inaccessible.
There is a problem with the default configuration, however.
Once you start to get a few tens or hundreds of files, the problem will manifest itself when you pull a directory listing, because ProFTPd will attempt to read the .ftpaccess files over, and over, and over again, and for each file in the directory, .ftpaccess is checked to see if the user should be allowed to view it.
You can disable this behavior in ProFTPd, but I would suggest that the most correct configuration is to configure additional options -o enable_noobj_cache -o stat_cache_expire=30 in s3fs:
-o stat_cache_expire (default is no expire)
specify expire time(seconds) for entries in the stat cache
Without this option, you'll make fewer requests to S3, but you also will not always reliably discover changes made to objects if external processes or other instances of s3fs are also modifying the objects in the bucket. The value "30" in my system was selected somewhat arbitrarily.
-o enable_noobj_cache (default is disable)
enable cache entries for the object which does not exist. s3fs always has to check whether file(or sub directory) exists under object(path) when s3fs does some command, since s3fs has recognized a directory which does not exist and has files or subdirectories under itself. It increases ListBucket request and makes performance bad. You can specify this option for performance, s3fs memorizes in stat cache that the object (file or directory) does not exist.
This option allows s3fs to remember that .ftpaccess wasn't there.
Unrelated to the performance issues that can arise with ProFTPd, which are resolved by the above changes, you also need to enable -o enable_content_md5 in s3fs.
-o enable_content_md5 (default is disable)
verifying uploaded data without multipart by content-md5 header. Enable to send "Content-MD5" header when uploading a object without multipart posting. If this option is enabled, it has some influences on a performance of s3fs when uploading small object. Because s3fs always checks MD5 when uploading large object, this option does not affect on large object.
This is an option which never should have been an option -- it should always be enabled, because not doing this bypasses a critical integrity check for only a negligible performance benefit. When an object is uploaded to S3 with a Content-MD5: header, S3 will validate the checksum and reject the object if it's corrupted in transit. However unlikely that might be, it seems short-sighted to disable this safety check.
Quotes are from the man page of s3fs. Grammatical errors are in the original text.
Answer from 2014 for the people who are down-voting me:
Well, S3 isn't FTP. There are lots and lots of clients that support S3, however.
Pretty much every notable FTP client on OS X has support, including Transmit and Cyberduck.
If you're on Windows, take a look at Cyberduck or CloudBerry.
Updated answer for 2019:
AWS has recently released the AWS Transfer for SFTP service, which may do what you're looking for.
Or spin Linux instance for SFTP Gateway in your AWS infrastructure that saves uploaded files to your Amazon S3 bucket.
Supported by Thorntech
Amazon has released SFTP services for S3, but they only do SFTP (not FTP or FTPES) and they can be cost prohibitive depending on your circumstances.
I'm the Founder of DocEvent.io, and we provide FTP/S Gateways for your S3 bucket without having to spin up servers or worry about infrastructure.
There are also other companies that provide a standalone FTP server that you pay by the month that can connect to an S3 bucket through the software configuration, for example brickftp.com.
Lastly there are also some AWS Marketplace apps that can help, here is a search link. Many of these spin up instances in your own infrastructure - this means you'll have to manage and upgrade the instances yourself which can be difficult to maintain and configure over time.
WinSCp now supports S3 protocol
First, make sure your AWS user with S3 access permissions has an “Access key ID” created. You also have to know the “Secret access key”. Access keys are created and managed on Users page of IAM Management Console.
Make sure New site node is selected.
On the New site node, select Amazon S3 protocol.
Enter your AWS user Access key ID and Secret access key
Save your site settings using the Save button.
Login using the Login button.
Filezilla just released a Pro version of their FTP client. It connects to S3 buckets in a streamlined FTP like experience. I use it myself (no affiliation whatsoever) and it works great.
As other posters have pointed out, there are some limitations with the AWS Transfer for SFTP service. You need to closely align requirements. For example, there are no quotas, whitelists/blacklists, file type limits, and non key based access requires external services. There is also a certain overhead relating to user management and IAM, which can get to be a pain at scale.
We have been running an SFTP S3 Proxy Gateway for about 5 years now for our customers. The core solution is wrapped in a collection of Docker services and deployed in whatever context is needed, even on-premise or local development servers. The use case for us is a little different as our solution is focused data processing and pipelines vs a file share. In a Salesforce example, a customer will use SFTP as the transport method sending email, purchase...data to an SFTP/S3 enpoint. This is mapped an object key on S3. Upon arrival, the data is picked up, processed, routed and loaded to a warehouse. We also have fairly significant auditing requirements for each transfer, something the Cloudwatch logs for AWS do not directly provide.
As other have mentioned, rolling your own is an option too. Using AWS Lightsail you can setup a cluster, say 4, of $10 2GB instances using either Route 53 or an ELB.
In general, it is great to see AWS offer this service and I expect it to mature over time. However, depending on your use case, alternative solutions may be a better fit.

Best way to stage file from cloud storage to windows machine

I am wanting to store a data file for Quickbooks in the cloud. I understand that the data file is more of a database-in-a-file, so I know that I don't want to simply have the data file itself in a cloud directory.
When I say 'cloud', I'm meaning something like Google Drive or box.com.
What I see working is that I want to write a script (bat file, or do they have something new and improved for Windows XP, like some .net nonsense or something?)
The script would:
1) Download the latest copy of the data file from cloud storage and put it in a directory on the local machine
2) Launch Quickbooks with that data file
3) When the user exits Quickbooks, copy the data file back up into the cloud storage.
4) Rejoice.
So, my question(s)... Is there something that already does this? Is there an easily scriptable interface to work with the cloud storage options? In my ideal world, I'd be able to say 'scp google-drive://blah/blah.dat localdir' and have it copy the file down, and do the opposite after running QB. I'm guessing I'm not going to get that.
Intuit already provides a product to do this. It is called Intuit Data Protect and it backs up your Quickbooks company file to the cloud for you.
http://appcenter.intuit.com/intuitdataprotect
regards,
Jarred