Using Node.js with Caché - InterSystems Documentation

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Introduction
This document describes cache.node, an add-on module for the Node.js environment that implements high performance
access to data held in Caché.
Node.js provides a means through which high performance and highly scalable network infrastructure can be easily created.
It is different from conventional thread based networking software (such as web servers) because it provides a non-blocking
event based architecture.
Most modern web servers are implemented using a hybrid multi-process/multithreaded server architecture where a thread
is dedicated to serving each request. All resources associated with that thread remain allocated until the request is satisfied
and a response dispatched to the client. In the Node.js architecture, a single process is used per instance (of node) and
threads are only used as a means through which operations and system calls that would otherwise block can be called
asynchronously with respect to the primary thread of execution. Everything happens asynchronously, and a primary design
feature is that no function should block, but rather accept a callback function that Node.js will use to notify the initiating
program that the operation has completed.
A consequence of the event based server architecture is that system resources (such as heap memory) are never tied-up
while waiting for some other operation to complete. Because of this, network programs developed using Node.js occupy
a very small footprint in terms of system resource and memory usage and a high level of scalability.
The cache.node module allows Caché to be leveraged as a high performance persistence storage engine that perfectly
complements the high performance Node.js environment. Caché multidimensional storage provides a very fast, flexible
storage model that can be used to implement a wide variety of data structures. The Caché cache.node module allows direct
access to globals, the basis of the multidimensional storage model (see Using Caché Globals for a formal description).
Caché can be regarded as a NoSQL database providing B-Tree based storage but with one important difference. Whereas
most B-Tree databases implement one-dimensional key/value storage, Caché provides a multi-dimensional multiple key/value
storage model. This provides the basis for a highly structured NoSQL data repository. In Caché terminology, each entry is
known as a "global node".
Examples:
One-dimensional Global Storage:
MyGlobal(“key1”)=”value1”
MyGlobal(“key2”)=”value2”
MyGlobal(“key3”)=”value3”
Multi-dimensional Global Storage:
Using Node.js with Caché 3