What's this?
A lightweight configurable condition rule check lib. Support simple condtion query syntax , just like mongo json query.
eg:
{
"a": "123",
"a.b": {"$gt":0, "$lt":10},
"$or": [{"a":1},{"c":{"$ne": "123"}}],
"c": {"$in": ["1", "2", "3"]},
"$and": [{"a.c": 100.001}, {"d": {"$regex": "go|home"}}]
}
(You can find more examples in unit test file: cond_test.go)
You can use it as a rule engine for condition check (run conditon check over the runtime data). Normally the Cond is a config data from config file or DB or API query.
Supports operators now:
| operators | dsc |
|---|---|
| $eq | eg: {"a": 123}, {"a": {"$eq": 123}} |
| $ne | {"a": {"$ne": 123}} |
| $gt | {"a": {"$gt": 123}} |
| $gte | {"a": {"$gte": 123}} |
| $lt | {"a": {"$lt": 123}} |
| $lte | {"a": {"$lte": 123}} |
| $and | {"$and": [{"a": 123}, {"b": 125}]} |
| $or | {"$or": [{"a": 123}, {"b": 125}]} |
| $in | {"a": {"$in": [1,2,3,4,5]} |
| $nin | {"b": {"$nin": [1,2,3,4,5]} |
| $regex | {"a": "$regex": "hello |
| $contain | {"a": {"$contain": "abc"}} |
How to use?
import (
"fmt"
"github.com/pozen/cond"
)
func main() {
// define a condition:
// { "key1": "123", "key2": {"$gt": 100} } ,
c := cond.Cond{
"key1": "123",
"key2": cond.Cond{"$gt": 100},
}
// create a cond state
s := cond.NewState().SetCond(c)
// example1: expect false
val_to_check := map[string]interface{}{
"key1": "123",
"key2": 99,
}
check_result := s.Exec(val_to_check)
fmt.Printf("check_result is: %v\n", check_result)
// example2: expect true
val_to_check = map[string]interface{}{
"key1": "123",
"key2": 200,
}
check_result = s.Exec(val_to_check)
fmt.Printf("check_result is: %v\n", check_result)
// example3: regex
c2 := cond.Cond{
"Key1.Key2": cond.Cond{"$regex": "hello|go"},
}
// struct as the value to check
type TVal struct {
Key1 struct {
Key2 string
}
}
var val_to_check2 TVal
val_to_check2.Key1.Key2 = "let's go!"
// reset cond & check
check_result = s.SetCond(c2).Exec(&val_to_check2)
fmt.Printf("regex check_result is: %v\n", check_result)
// example4: varible
val_to_check = map[string]interface{}{
"key1": 123,
"key2": 200,
}
c3 := cond.Cond{
"key1": cond.Cond{"$lt": "&key2"},
}
check_result = s.SetCond(c3).Exec(val_to_check)
fmt.Printf("variable check_result is: %v\n", check_result)
}