Using RedisJSON to store nested data

Let’s say you want to utilize redis to store and manipulate this JSON

{
      "name": "Garfield",
      "traits": {
        "lazy": true,
        "hungry": true,
        "sassy": true,
        "loves_lasagna": true,
        "hates_mondays": true
      }
}Code language: JSON / JSON with Comments (json)

You can use the module RedisJSON to do it.

Prerequisites

If you don’t have the module installed you must build it first.

You’ll need to install these first (example commands are for Rocky Linux, but should be at least similar to other distros)

• gcc

dnf install gcc

• clang

dnf install clang-devel clang-libs

• git

dnf install git

The build process is

Install Cargo

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | shCode language: JavaScript (javascript)

Load the Cargo environment

source "$HOME/.cargo/env"Code language: JavaScript (javascript)

Get the RedisJSON source from https://github.com/RedisJSON/RedisJSON

git clone https://github.com/RedisJSON/RedisJSON.gitCode language: PHP (php)

Go into the RedisJSON source directory

cd RedisJSON

Build it using Cargo

cargo build --release

You’ll find the built module in the directory /target/release/ with the name librejson.so

Create a directory for the modules

mkdir /etc/redis/modules

Copy the module to the newly created directory. Assuming you’re in RedisJSON source directory the command is

cp /target/release/librejson.so /etc/redis/modules/

Edit the configuration so Redis load the new module

vim /etc/redis/redis.conf

################################## MODULES #####################################

# Load modules at startup. If the server is not able to load modules
# it will abort. It is possible to use multiple loadmodule directives.
#
# loadmodule /path/to/my_module.so
# loadmodule /path/to/other_module.so
<strong>loadmodule /etc/redis/modules/librejson.so</strong>
Code language: PHP (php)

Restart your Redis service. If you’re using sentinel or cluster, its safer to do this after the module is installed in all of the nodes.

service redis restart

Play with the RedisJSON module

After installation you can then use the commands in redis-cli or any suppored library.

Example using redis-cli

Insert the JSON

JSON.SET animal:garfield $ ’ { "name": "Garfield", "traits": { "lazy": true, "hungry": true, "sassy": true, "loves_lasagna": true, "hates_mondays": true } }’Code language: JavaScript (javascript)

Get Garfield’s traits

JSON.GET animal:Garfield $.traitsCode language: JavaScript (javascript)

Get the value of whether Garfield is lazy or not

JSON.GET animal:Garfield $.traits.lazyCode language: JavaScript (javascript)

Additional note

The maximum depth of the JSON object is 128