1 // Copyright (c) 2020 Uber Technologies, Inc. 2 // 3 // Permission is hereby granted, free of charge, to any person obtaining a copy 4 // of this software and associated documentation files (the "Software"), to deal 5 // in the Software without restriction, including without limitation the rights 6 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 7 // copies of the Software, and to permit persons to whom the Software is 8 // furnished to do so, subject to the following conditions: 9 // 10 // The above copyright notice and this permission notice shall be included in 11 // all copies or substantial portions of the Software. 12 // 13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 14 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 15 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 16 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 17 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 18 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 19 // THE SOFTWARE. 20 21 package zapcore 22 23 import "fmt" 24 25 type levelFilterCore struct { 26 core Core 27 level LevelEnabler 28 } 29 30 var ( 31 _ Core = (*levelFilterCore)(nil) 32 _ leveledEnabler = (*levelFilterCore)(nil) 33 ) 34 35 // NewIncreaseLevelCore creates a core that can be used to increase the level of 36 // an existing Core. It cannot be used to decrease the logging level, as it acts 37 // as a filter before calling the underlying core. If level decreases the log level, 38 // an error is returned. 39 func NewIncreaseLevelCore(core Core, level LevelEnabler) (Core, error) { 40 for l := _maxLevel; l >= _minLevel; l-- { 41 if !core.Enabled(l) && level.Enabled(l) { 42 return nil, fmt.Errorf("invalid increase level, as level %q is allowed by increased level, but not by existing core", l) 43 } 44 } 45 46 return &levelFilterCore{core, level}, nil 47 } 48 49 func (c *levelFilterCore) Enabled(lvl Level) bool { 50 return c.level.Enabled(lvl) 51 } 52 53 func (c *levelFilterCore) Level() Level { 54 return LevelOf(c.level) 55 } 56 57 func (c *levelFilterCore) With(fields []Field) Core { 58 return &levelFilterCore{c.core.With(fields), c.level} 59 } 60 61 func (c *levelFilterCore) Check(ent Entry, ce *CheckedEntry) *CheckedEntry { 62 if !c.Enabled(ent.Level) { 63 return ce 64 } 65 66 return c.core.Check(ent, ce) 67 } 68 69 func (c *levelFilterCore) Write(ent Entry, fields []Field) error { 70 return c.core.Write(ent, fields) 71 } 72 73 func (c *levelFilterCore) Sync() error { 74 return c.core.Sync() 75 } 76