GeodeREST

Apache Geode provides a database-like consistency model, reliable transaction processing and a shared-nothing architecture to maintain very low latency performance with high concurrency processing.

Java users can use the Geode client or peer API (API Reference). The other method is Spring Data GemFire or Spring Cache.

For C++ or C# users, you can check Apache Geode native components.

Gemcached is a Geode adapter that allows Memcached clients to communicate with a Geode server cluster, as if the servers were memcached servers. So User can use memcached clients to access data stored in embedded Gemcached servers.

Geode Redis Adapter called GemFireRedisServer, understands the Redis protocol but uses Geode underneath as the data store. The point of emphasis in this server adapter is to handle all of the data types normally implemented in Redis. This includes Strings, Lists, Hashes, Sets and SortedSets and HyperLogLogs.

The other method is using Apache Geode REST APIs to access region data.

This extension is an Apache Geode REST Client Library for Tcl. The library consists of a single Tcl Module file.

GeodeREST is using Tcl built-in package http to send request to Apache Geode server REST interface and get response.

This extension needs Tcl 8.6, tcllib base64 and tcllib json package.

Interface

The library has 1 TclOO class, GeodeREST.

Example

Add, update and delete value

package require GeodeREST

set mygeode [GeodeREST new http://localhost:8080]
if {[$mygeode connect]==0} {
    puts "Http status code is not OK, exit"
    exit
}

puts "Current regions:"
puts [$mygeode list_all_regions]

$mygeode setupRegion regionA
$mygeode create "myKey" {{"hello": "world"}}
$mygeode create "myKey2" {{"hello2": "world2"}}
$mygeode put "myKey" {{"hello": "Beautiful world"}}
$mygeode get "myKey"
$mygeode update "myKey" {{"hello": "world"}}
$mygeode get "myKey"
$mygeode compare_and_set "myKey" {{"hello": "world"}} {{"hello": "Beautiful world"}}
$mygeode get "myKey"

puts "Current data:"
puts [$mygeode get_all]

# delete value
$mygeode delete "myKey2"
$mygeode delete_all

Query example

Apache Geode provides a SQL-like querying language called OQL (Object Query Language) that allows you to access data stored in Geode regions.

Using REST APIs, you can create and execute either prepared or ad-hoc queries on Geode regions.

puts "adhoc query:"
puts [$mygeode adhoc_query "SELECT * FROM /regionA"]

puts "specified parameterized query:"
$mygeode new_query "myQuery" {SELECT * FROM /regionA r WHERE r.hello = $1}
puts [$mygeode list_all_queries]
puts [$mygeode run_query "myQuery" {[{"@type": "string", "@value": "Beautiful world"}]}]
$mygeode delete_query "myQuery"

HTTPS support

If user enables HTTPS support, below is an example:

package require GeodeREST

set mygeode [GeodeREST new https://localhost:8080 1]
if {[$mygeode connect]==0} {
    puts "Http status code is not OK, exit"
    exit
}

Please notice, I use TLS extension to add https support. So https support needs TLS extension.

HTTP Basic Authentication support

If users enable org.apache.geode.security.SecurityManager and setup "security.json" file correctly, Geode use HTTP Basic Authentication for enforcing access controls to web resources (at version 1.1.0). You can get more info at Using Custom SecurityManager.

package require GeodeREST

set mygeode [GeodeREST new https://localhost:8080 1]
$mygeode setAuthType "basic"
$mygeode setUsername "joebloggs"
$mygeode setPassword "1234567"

if {[$mygeode connect]==0} {
    puts "Http status code is not OK, exit"
    exit
}