Getting Started with Redis: Concepts, Commands, and Monitoring
Redis is a in-memory NoSQL database mainly used for caching. It's a key-value store which means each unique keys map to a value which could be either a stirng, list, set, hash, blob, JSON or any other data. Each keys are unique and can be queried.
Connecting to a Redis Cluster
To connect to a Redis cluster securely using the command line, you can use the redis-cli tool with TLS and authentication:
Common Redis Operations
Common redis operations across different data types:
String Operations
Strings are the simplest Redis data type. A Redis string value can be up to 512 MB in size
List Operations
Redis Lists are implemented as linked lists, optimized for fast insertions and deletions from both ends.
Hash Operations
Hashes are maps between string fields and string values, ideal for representing objects.
Set Operations
Sets are unordered collections of unique strings. They support powerful set algebra operations.
Sorted Set Operations
Sorted Sets are similar to Sets but with an associated score that allows ordering.
Key Management & Expiration
Redis allows setting time-to-live (TTL) on keys and inspecting their status.
Monitoring Redis Memory Usage
Use the INFO MEMORY command to inspect memory consumption:
Subscribing to Keyspace Events
Redis provides a pub/sub mechanism to monitor events such as key updates, deletions, and expirations. To subscribe to all events under the myApp namespace:
Automating Event Monitoring with Python
You can automate monitoring of Redis keyspace events using Python and the redis library. The following script connects to Redis, subscribes to a pattern, and logs events to both a file and the console:
Sample Output:
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