Overview
Communication
Send messages between Amazon EC2 instances through Unix pipes.
Communication in aws_pipes is built on top of the Amazon Simple Queue Service (SQS) which lets you
- Move data between distributed components of your application without losing messages or requiring each component to be always available.
- Get started with no extra installed software or special firewall configurations.
- Connect machines on different networks, developed with different technologies, and running at different times.
- Save messages in the queue for up to 14 days.
Text is the universal interface, and any application that can read and write text can use this gem – no knowledge of the Amazon API is required.
Logging
Consolidate logs between EC2 instances. Logging in aws_pipes is built on top of Amazon SimpleDB.
- Get logs off individual servers to save disk space.
- Pool the log messages from related workers.
- Monitor and query logs from one place.
- Save as much log history as you want, the storage is virtually unlimited.
Saving Datasets
Save data across EC2 instances with scalable throughput. Data archival in aws_pipes is built on top of Amazon DynamoDB.
- Store data centrally.
- Automatically scale throughput and space.
- Query results (albeit not relationally).
- Monitor data acquisition through web control panel.
- Can export to S3.
Usage
aws_queue
# write data to an SQS queue named "foo"
your_program | aws_queue write foo
# read data from an SQS queue named "foo"
aws_queue read foo | your_program
To use this program you will need to create a queue in the Amazon Web Console.
aws_log
# write stderr to log named "bar"
your_program 2> >(aws_log record bar)
# delete all messages in log named "bar"
aws_log delete bar
# View log entries for "bar" within a date range
aws_log show bar --after "1970-01-01" --before "2020-02-02 13:42:12.123"
Each line sent to the log gets marked with a timestamp and the external IP address of the machine which added it.
You can combine queuing and logging in a single command using Bash process substitution:
# write stdout to an SQS queue named "foo"
# while logging stderr to a log named "bar"
your_program 1> >(aws_queue write foo) 2> >(aws_log record bar)
aws_db
# save each tab-delimited line of as a row in DynamoDB table foo
# filling in columns a, b, and c
your_program | aws_db foo a b c
DynamoDB tables have adjustable read- and write-throughput settings to
scale as needed. The aws_db
command will automatically re-provision
write throughput if writing starts getting throttled. This makes
aws_db
(when run in parallel) a way to save virtually unlimited
amounts of data as quickly as necessary.
Installation
- Sign up for an AWS account.
- Find your secret key and key id in My Account > Security Credentials.
- (optionally) Set your environment variables AWS_ACCESS_KEY_ID, and AWS_ACCESS_KEY accordingly.
- Run
gem install aws_pipes
from the command line.
This will install the aws_queue
and aws_log
commands to your path.
If you haven't stored your Amazon credentials in environment variables,
you can pass them in as command line options. For more info, run
aws_queue --help
Examples
Downloading a massive list of urls in parallel.
One computer can feed a list of urls to workers which download them.
Suppose the urls are stored in urls.txt
. Just redirect the file into a
queue:
aws_queue write to_be_downloaded < urls.txt
Then have each worker pull from the to_be_downloaded
queue and
repeatedly run a command to download each url. The queue supports many
simultaneous readers and prevents duplicate work. We save any errors to
a log named "downloader" which we can monitor remotely.
aws_queue read to_be_downloaded | xargs -L1 wget -nv 2> >(aws_log record downloader)