Redis Cache

Redis cache is a high-performance caching service based on Redis in-memory database, providing distributed caching capabilities and rich data operation functions. It encapsulates Redis client connection management and standard cache operation interfaces, supporting multiple data structure operations, expiration time control, and connection pool management, suitable for high-concurrency and low-latency application scenarios.

The hierarchical structure of Redis cache elements is Meta (caches.Meta) → Type (caches.RedisType) → Instance. Developers can quickly create Redis cache instances through JitAi's visual development tools.

Of course, developers can also create their own Type elements or modify the official caches.RedisType element provided by JitAi in their own App to implement their own encapsulation.

Quick Start

Creating Instance Elements

Recommended Directory Structure

caches/
└── MyRedis/              # Cache instance name (path can be customized)
    ├── e.json            # Element declaration file
    ├── MyRedis.json      # Redis connection configuration file
    └── __init__.py       # Optional initialization file

e.json File

Element Declaration Configuration

{
  "backendBundleEntry": ".",
  "title": "My Redis Cache",
  "type": "caches.RedisType"
}

Method Interfaces

Standard Cache Operations

Provides standard cache read/write and management methods.

Business Configuration File

Redis Connection Configuration (MyRedis.json)

{
  "host": "127.0.0.1",
  "port": 6379,
  "password": "your_password"
}

Usage Example

Using Redis Cache

# Get cache instance
cache = app.getElement("caches.MyRedis")

# Basic string operations
cache.set("user:1001", "张三", 3600)  # Set user info, expire in 1 hour
user_name = cache.get("user:1001")   # Get user info

# Numeric operations
cache.setNumeric("visit_count", 100)      # Set visit count
count = cache.getNumeric("visit_count")   # Get visit count
new_count = cache.incr("visit_count", 5)  # Increase by 5 visits

# Expiration time control
cache.expire("session:abc123", 1800)  # Extend session expiration to 30 minutes

# Key management
if cache.exists("user:1001"):         # Check if key exists
    cache.delete("user:1001")         # Delete key

Element Configuration

e.json Configuration

Configuration Item	Type	Required	Description
backendBundleEntry	str	Yes	Backend bundle entry, fixed value "."
title	str	Yes	Display name of cache instance
type	str	Yes	Fixed value "caches.RedisType"
icon	str	No	Icon identifier, customizable

Business Configuration File

Parameter Name	Type	Corresponding Native Type	Required	Description
host	str	str	Yes	Redis server address
port	int	int	Yes	Redis server port
password	str	str	Yes	Redis connection password
db	int	int	No	Database number, default 1
username	str	str	No	Username, default "default"
charset	str	str	No	Character encoding, default "utf-8"
decode_responses	bool	bool	No	Whether to decode responses, default true
socket_timeout	float	float	No	Socket timeout, default 0.5 seconds
socket_connect_timeout	float	float	No	Connection timeout, default 0.5 seconds

Methods

get

Get string value from cache.

Parameter Details

Parameter Name	Type	Corresponding Native Type	Required	Description
name	str	str	Yes	Cache key name

Return Value

• Type: str
• Description: String value corresponding to key, returns None if not exists

Usage Example

Get Cache Value

cache = app.getElement("caches.MyRedis")
value = cache.get("user_token")
if value:
    print(f"User token: {value}")

set

Write string data to cache.

Parameter Details

Parameter Name	Type	Corresponding Native Type	Required	Description
name	str	str	Yes	Cache key name
string	str	str	Yes	String value to store
ts	int	int	No	Expiration time (seconds), None means never expires

Return Value

• Type: bool
• Description: Returns True on success, False on failure

Usage Example

Set Cache Value

cache = app.getElement("caches.MyRedis")

# Set permanent cache
success = cache.set("config:theme", "dark")

# Set cache with expiration time
success = cache.set("verification_code", "123456", 300)  # Expires in 5 minutes

getNumeric

Get numeric type cache.

Parameter Details

Parameter Name	Type	Corresponding Native Type	Required	Description
name	str	str	Yes	Cache key name

Return Value

• Type: int
• Description: Numeric value corresponding to key, returns 0 if not exists

Usage Example

Get Numeric Cache

cache = app.getElement("caches.MyRedis")
count = cache.getNumeric("page_views")
print(f"Page views: {count}")

setNumeric

Set numeric type cache.

Parameter Details

Parameter Name	Type	Corresponding Native Type	Required	Description
name	str	str	Yes	Cache key name
n	int	int	No	Numeric value to set, default 0
ts	int	int	No	Expiration time (seconds), None means never expires

Return Value

• Type: bool
• Description: Returns True on success, False on failure

Usage Example

Set Numeric Cache

cache = app.getElement("caches.MyRedis")

# Initialize counter
cache.setNumeric("download_count", 1000)

# Set rate limiting counter with expiration time
cache.setNumeric("api_calls:user123", 0, 3600)  # Expires in 1 hour

incr

Perform increment operation on numeric value.

Parameter Details

Parameter Name	Type	Corresponding Native Type	Required	Description
name	str	str	Yes	Cache key name
amount	int	int	No	Increment value, default 1

Return Value

• Type: int
• Description: New value after increment

Usage Example

Numeric Increment Operation

cache = app.getElement("caches.MyRedis")

# Simple counting
new_count = cache.incr("visit_count")

# Batch increment
batch_count = cache.incr("download_count", 10)
print(f"Current downloads: {batch_count}")

expire

Update cache expiration time.

Parameter Details

Parameter Name	Type	Corresponding Native Type	Required	Description
name	str	str	Yes	Cache key name
ts	int	int	Yes	New expiration time (seconds)

Return Value

• Type: bool
• Description: Returns True on success, False on failure

Usage Example

Update Expiration Time

cache = app.getElement("caches.MyRedis")

# Extend session expiration time
if cache.exists("session:user123"):
    cache.expire("session:user123", 7200)  # Extend to 2 hours

exists

Check if cache key exists.

Parameter Details

Parameter Name	Type	Corresponding Native Type	Required	Description
name	str	str	Yes	Cache key name

Return Value

• Type: bool
• Description: Returns True if key exists, False if not

Usage Example

Check Key Existence

cache = app.getElement("caches.MyRedis")

if cache.exists("user_cache:1001"):
    print("User cache exists")
else:
    print("Need to reload user data")

delete

Delete cache key.

Parameter Details

Parameter Name	Type	Corresponding Native Type	Required	Description
name	str	str	Yes	Cache key name to delete

Return Value

• Type: bool
• Description: Returns True on success, False on failure

Usage Example

Delete Cache

cache = app.getElement("caches.MyRedis")

# Clear user session
success = cache.delete("session:user123")
if success:
    print("Session cleared")

keys

Get list of keys matching pattern.

Parameter Details

Parameter Name	Type	Corresponding Native Type	Required	Description
pattern	str	str	No	Match pattern, default "*" means all keys

Return Value

• Type: iterator
• Description: Returns iterator of matching key names

Usage Example

Find Matching Keys

cache = app.getElement("caches.MyRedis")

# Find all user sessions
for key in cache.keys("session:*"):
    print(f"Session key: {key}")

# Find configs with specific prefix
config_keys = list(cache.keys("config:*"))

ping

Test Redis connection status.

Usage Example

Test Connection

cache = app.getElement("caches.MyRedis")

if cache.ping():
    print("Redis connection normal")
else:
    print("Redis connection abnormal")

disconnect

Disconnect Redis connection.

Usage Example

Disconnect

cache = app.getElement("caches.MyRedis")
cache.disconnect()

Properties

Redis cache elements mainly provide functionality through methods, with no directly accessible public properties currently.

Advanced Features

Connection Pool Management

Redis cache automatically manages connection pools. Instances with the same configuration will reuse connections, improving performance and reducing resource consumption.

Connection Pool Reuse Example

# Multiple instances with same configuration will automatically reuse connections
cache1 = app.getElement("caches.Redis1")
cache2 = app.getElement("caches.Redis2")  # If configuration is same, will reuse connection pool

Automatic Key Name Prefix Management

All cache operations automatically add application ID prefix, avoiding key name conflicts between different applications.

Key Name Prefix Mechanism

# Actual stored key names automatically add application ID prefix
cache.set("user_data", "value")
# Actually stored as: "myapp:user_data"

Environment Variable Configuration

Configuration files support template strings, allowing dynamic configuration using environment variables.

Configuration Example Using Environment Variables

{
  "host": "{{REDIS_HOST}}",
  "port": "{{REDIS_PORT}}",
  "password": "{{REDIS_PASSWORD}}",
  "db": 1
}

Exception Handling

Redis cache provides comprehensive exception handling mechanisms. Connection failures and authentication errors are automatically converted to friendly error messages.

Exception Handling Example

try:
    cache = app.getElement("caches.MyRedis")
    cache.set("test_key", "test_value")
except Exception as e:
    # System automatically handles connection exceptions, providing clear error messages
    print(f"Cache operation failed: {e}")