Add query package with first set of conditions and tests

database/query/condition-int.go

@@ -0,0 +1,86 @@
+package query
+
+import (
+	"errors"
+	"fmt"
+	"strconv"
+)
+
+type intCondition struct {
+	key      string
+	operator uint8
+	value    int64
+}
+
+func newIntCondition(key string, operator uint8, value interface{}) *intCondition {
+
+	var parsedValue int64
+
+	switch v := value.(type) {
+	case int:
+		parsedValue = int64(v)
+	case int8:
+		parsedValue = int64(v)
+	case int16:
+		parsedValue = int64(v)
+	case int32:
+		parsedValue = int64(v)
+	case int64:
+		parsedValue = int64(v)
+	case uint:
+		parsedValue = int64(v)
+	case uint8:
+		parsedValue = int64(v)
+	case uint32:
+		parsedValue = int64(v)
+	case string:
+		var err error
+		parsedValue, err = strconv.ParseInt(v, 10, 64)
+		if err != nil {
+			return &intCondition{
+				key:      fmt.Sprintf("could not parse %s to int64: %s (hint: use \"sameas\" to compare strings)", v, err),
+				operator: errorPresent,
+			}
+		}
+	default:
+		return &intCondition{
+			key:      fmt.Sprintf("incompatible value %v for int64", value),
+			operator: errorPresent,
+		}
+	}
+
+	return &intCondition{
+		key:      key,
+		operator: operator,
+		value:    parsedValue,
+	}
+}
+
+func (c *intCondition) complies(f Fetcher) bool {
+	comp, ok := f.GetInt(c.key)
+	if !ok {
+		return false
+	}
+
+	switch c.operator {
+	case Equals:
+		return comp == c.value
+	case GreaterThan:
+		return comp > c.value
+	case GreaterThanOrEqual:
+		return comp >= c.value
+	case LessThan:
+		return comp < c.value
+	case LessThanOrEqual:
+		return comp <= c.value
+	default:
+		return false
+	}
+}
+
+func (c *intCondition) check() error {
+	if c.operator == errorPresent {
+		return errors.New(c.key)
+	}
+	return nil
+}