basic

Basic cache

This example demonstrates a typical cache-aside workflow with pacecache and an in-memory user repository.

Key Concepts Covered

• Configuring a bounded generic cache with TTL and jitter
• Configuring a default loader and loading missing values with GetOrLoad
• Reading cached values and expiration metadata with Get and GetEntry
• Handling missing loader results without caching them
• Deleting cached values and reloading them from the repository
• Inspecting cache state and cumulative statistics

Run

Run the example from this directory:

go run .

Or from the repository root:

go run ./examples/basic

Example Output

cache:
- first lookup: found=true user={ID:42 Name:Ada}
- direct lookup: user={ID:42 Name:Ada}
- entry has expiration: true
- repository loads: 1

not found:
- first lookup: found=false
- second lookup: found=false
- repository loads: 3

deletion:
- lookup after deletion: found=true user={ID:42 Name:Ada}
- repository loads: 4

stats:
- entries=1 hits=2 misses=4
- loads_found=2 loads_not_found=2 load_errors=0
- deleted_entries=1 evictions=0 expirations=0

• Cache-Aside Loading: The first lookup for user 42 loads the value from the repository and stores it in the cache. Subsequent Get and GetEntry operations return the cached value without calling the repository again, so the repository load count remains at 1.
• Missing Results: Missing results are not cached. Looking up user 404 twice therefore invokes the repository twice and produces two not_found loader outcomes.
• Deletion: After Delete(42), the next lookup loads the value from the repository again and stores the fresh result in the cache, increasing the repository load count to 4.