Gorm-Plus

Gorm-Plus enhances GORM with several out-of-the-box capabilities:

1. Non-intrusive Enhancement: Maintains original GORM features and compatibility while adding new ones.
2. Powerful CRUD & Universal Querying: Simplifies complex conditional queries without tedious configuration.
3. Pointer Field Querying: Supports querying via pointer fields to prevent errors caused by incorrect field names.
4. Generic Queries: Built-in generic query support allows for flexible return type encapsulation.
5. Built-in Pagination: Includes a pagination plugin to handle large datasets efficiently.

Gorm-Plus is designed to be non-intrusive. To integrate it into your existing application, initialize it by passing your existing *gorm.DB instance to gplus.Init() after opening the database connection.

// ... gorm.Open setup ...

// Initialize gplus
gplus.Init(gormDb)

Gorm-Plus provides a powerful way to convert URL query parameters into complex database queries using gplus.BuildQuery[T]. This allows you to implement single-table search functionality with minimal code.

func handleRequest(w http.ResponseWriter, r *http.Request) {
  queryParams := r.URL.Query()
  // Build query from URL params and execute selection
  list, _ := gplus.SelectList(gplus.BuildQuery[User](queryParams))
  
  marshal, _ := json.Marshal(list)
  w.Write(marshal)
}

To use Gorm-Plus in your Go project, download it using go get:

go get github.com/acmestack/gorm-plus

Use gplus.SelectList[T] to perform a select query for a specific model type T. It returns a slice of the model and a *gorm.DB instance containing error and metadata information (like RowsAffected).

// Example: Selecting all users
users, resultDb := gplus.SelectList[User](nil)
if resultDb.Error != nil {
    log.Println("error:", resultDb.Error)
}
log.Println("RowsAffected:", resultDb.RowsAffected)
for _, user := range users {
    log.Println("user:", user)
}

When using gplus.BuildQuery, you can construct various query conditions via URL parameters using the q key and special operators.

Supported Patterns:

• Equality: q=field=value (e.g., q=username=zhangsan)
• Pattern Matching: q=field~>=prefix (e.g., q=username~>=zhang for names starting with 'zhang')
• Comparison: q=field>value (e.g., q=age>20)
• Multiple Conditions (AND): Use multiple q parameters (e.g., q=username=zhangsan&q=password=123456)
• Logical Grouping (OR): Use group identifiers (A, B, etc.) and the gcond parameter to define OR logic (e.g., q=A.username=zhangsan&q=B.username=lisi&gcond=A|B)