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Stargate Scanner Filter Examples

Introduction

So yeah... no documentation for the HBase REST API in regards to what should a filter look like...

So I installed Eclipse, got the library, and took some time to find some of the (seemingly) most useful filters you could use. I'm very green at anything regarding HBase, and I hope this will help anyone trying to get started with it.

What I discovered is that basically, attributes of the filter object follow the same naming than in the documentation. For this reason, I have made the link clickable and direct them to the HBase Class documentation attached to it; check for the instantiation argument names, and you will have your attribute list (more or less).

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Scaling your API with rate limiters

The following are examples of the four types rate limiters discussed in the accompanying blog post. In the examples below I've used pseudocode-like Ruby, so if you're unfamiliar with Ruby you should be able to easily translate this approach to other languages. Complete examples in Ruby are also provided later in this gist.

In most cases you'll want all these examples to be classes, but I've used simple functions here to keep the code samples brief.

Request rate limiter

This uses a basic token bucket algorithm and relies on the fact that Redis scripts execute atomically. No other operations can run between fetching the count and writing the new count.

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Using OTP's observer (appmon replacement) remotely

$ ssh remote-host "epmd -names"
epmd: up and running on port 4369 with data:
name some_node at port 58769

Note the running on port for epmd itself and the port of the node you're interested in debugging. Reconnect to the remote host with these ports forwarded:

$ ssh -L 4369:localhost:4369 -L 58769:localhost:58769 remote-host