76 lines
3.1 KiB
Markdown
76 lines
3.1 KiB
Markdown
|
## null [](https://godoc.org/github.com/guregu/null) [](http://gocover.io/github.com/guregu/null)
|
||
|
|
`import "gopkg.in/guregu/null.v3"`
|
||
|
|
|
||
|
|
null is a library with reasonable options for dealing with nullable SQL and JSON values
|
||
|
|
|
||
|
|
There are two packages: `null` and its subpackage `zero`.
|
||
|
|
|
||
|
|
Types in `null` will only be considered null on null input, and will JSON encode to `null`. If you need zero and null be considered separate values, use these.
|
||
|
|
|
||
|
|
Types in `zero` are treated like zero values in Go: blank string input will produce a null `zero.String`, and null Strings will JSON encode to `""`. Zero values of these types will be considered null to SQL. If you need zero and null treated the same, use these.
|
||
|
|
|
||
|
|
All types implement `sql.Scanner` and `driver.Valuer`, so you can use this library in place of `sql.NullXXX`. All types also implement: `encoding.TextMarshaler`, `encoding.TextUnmarshaler`, `json.Marshaler`, and `json.Unmarshaler`.
|
||
|
|
|
||
|
|
### null package
|
||
|
|
|
||
|
|
`import "gopkg.in/guregu/null.v3"`
|
||
|
|
|
||
|
|
#### null.String
|
||
|
|
Nullable string.
|
||
|
|
|
||
|
|
Marshals to JSON null if SQL source data is null. Zero (blank) input will not produce a null String. Can unmarshal from `sql.NullString` JSON input or string input.
|
||
|
|
|
||
|
|
#### null.Int
|
||
|
|
Nullable int64.
|
||
|
|
|
||
|
|
Marshals to JSON null if SQL source data is null. Zero input will not produce a null Int. Can unmarshal from `sql.NullInt64` JSON input.
|
||
|
|
|
||
|
|
#### null.Float
|
||
|
|
Nullable float64.
|
||
|
|
|
||
|
|
Marshals to JSON null if SQL source data is null. Zero input will not produce a null Float. Can unmarshal from `sql.NullFloat64` JSON input.
|
||
|
|
|
||
|
|
#### null.Bool
|
||
|
|
Nullable bool.
|
||
|
|
|
||
|
|
Marshals to JSON null if SQL source data is null. False input will not produce a null Bool. Can unmarshal from `sql.NullBool` JSON input.
|
||
|
|
|
||
|
|
#### null.Time
|
||
|
|
|
||
|
|
Marshals to JSON null if SQL source data is null. Uses `time.Time`'s marshaler. Can unmarshal from `pq.NullTime` and similar JSON input.
|
||
|
|
|
||
|
|
### zero package
|
||
|
|
|
||
|
|
`import "gopkg.in/guregu/null.v3/zero"`
|
||
|
|
|
||
|
|
#### zero.String
|
||
|
|
Nullable string.
|
||
|
|
|
||
|
|
Will marshal to a blank string if null. Blank string input produces a null String. Null values and zero values are considered equivalent. Can unmarshal from `sql.NullString` JSON input.
|
||
|
|
|
||
|
|
#### zero.Int
|
||
|
|
Nullable int64.
|
||
|
|
|
||
|
|
Will marshal to 0 if null. 0 produces a null Int. Null values and zero values are considered equivalent. Can unmarshal from `sql.NullInt64` JSON input.
|
||
|
|
|
||
|
|
#### zero.Float
|
||
|
|
Nullable float64.
|
||
|
|
|
||
|
|
Will marshal to 0 if null. 0.0 produces a null Float. Null values and zero values are considered equivalent. Can unmarshal from `sql.NullFloat64` JSON input.
|
||
|
|
|
||
|
|
#### zero.Bool
|
||
|
|
Nullable bool.
|
||
|
|
|
||
|
|
Will marshal to false if null. `false` produces a null Float. Null values and zero values are considered equivalent. Can unmarshal from `sql.NullBool` JSON input.
|
||
|
|
|
||
|
|
#### zero.Time
|
||
|
|
|
||
|
|
Will marshal to the zero time if null. Uses `time.Time`'s marshaler. Can unmarshal from `pq.NullTime` and similar JSON input.
|
||
|
|
|
||
|
|
|
||
|
|
### Bugs
|
||
|
|
`json`'s `",omitempty"` struct tag does not work correctly right now. It will never omit a null or empty String. This might be [fixed eventually](https://github.com/golang/go/issues/4357).
|
||
|
|
|
||
|
|
### License
|
||
|
|
BSD
|