Deprecated: use git.fractalqb.de/fractalqb/daq instead
README
¶
ggja
import "git.fractalqb.de/fractalqb/ggja"
Intro
Go Generic JSON Api is a small helper library to make working with Go's generic JSON types more comfortable.
Instead of writing this code fragment
if tmp, ok := genJson["key"]; !ok {
log.Panic("no member key in JSON object")
} else {
i := tmp.(int)
}
with ggja it can be somewhat shorter:
i := ggjaObj.MInt("key")
OK, one first has to wrap the generic JSON genJson map[string]interface{}
into a ggja object wrapper:
ggjaObj := ggja.Obj{Bare: genJson}
i := ggjaObj.MInt("key") // Must Int or…
j := ggjaObj.Int("key", 4711) // with default value
Perhaps you don't like to simply panic and customize the error handling:
ggjaObj.OnError = func(err error) { log.Fatal(err) }
But this is only done once and—also useful—you can pass the error handling
strategy around with the ggjaObj.
For more details read on or consult godoc.
JSON Array Element by Index
Simply by index (that's it for now):
strVal := ggjaArr.Str(3, strVal)
Updates strVal in case ggjaArr has at least four elements.
Access Methods for Basic Types
Access methods for basic types come in two flavours:
-
A conditional one, that returns a default value
nvlif the requested value is not in the JSON object or array. Those methods are simply called after the type they return, e.g.ggjaObj.Str("name", "-")returns a string. -
A mandatory flavour that calls your provided
OnErrorfunction if the requested value is not preset. If you provide no error function it willpanicinstead. Mandatory access methods start with 'M', e.g.MInt(…)
Access Methods for Array and Objects
Besides the access methods for basic types there are also access methods for
objects and arrays. Both come in the two flavours conditional and mandatory.
The conditional access for arrays and objects does not have a default value
but returns nil in case the is nothing that can be accessed.
However array element and object member access have a third generating
flavour that creates an empty array resp. object on access if needed. Generating
access methods start with 'C' for create, e.g. CObj(…).
ggjaArr := Arr{OnError: fail}
objMbr3 := ggjaArr.CObj(3)
objMbr3.Put("name", "John Doe")
jStr, _ := json.Marshal(ggjaArr.Bare)
fmt.Println(string(jStr))
jStr, _ = json.Marshal(objMbr3.Bare)
fmt.Println(string(jStr))
writes output
[null,null,null,{"name":"John Doe"}]
{"name":"John Doe"}
Documentation
¶
Overview ¶
Package ggja—the Go Generic JSON Api—is a small helper library to make working with Go's generic JSON types more comfortable.
Index ¶
- func Get(v interface{}, path ...interface{}) (interface{}, error)
- func GetString(v interface{}, path ...interface{}) (string, error)
- func Recover(err *error)
- type Arr
- func (a *Arr) Arr(idx int) *Arr
- func (a *Arr) Bool(idx int, nvl bool) bool
- func (a *Arr) CArr(idx int) (elm *Arr)
- func (a *Arr) CObj(idx int) (elm *Obj)
- func (a *Arr) F32(idx int, nvl float32) float32
- func (a *Arr) F64(idx int, nvl float64) float64
- func (a *Arr) Ignoring(errs ...error) *Arr
- func (a *Arr) Int(idx int, nvl int) int
- func (a *Arr) Len() int
- func (a *Arr) MArr(idx int) *Arr
- func (a *Arr) MBool(idx int) bool
- func (a *Arr) MF32(idx int) float32
- func (a *Arr) MF64(idx int) float64
- func (a *Arr) MInt(idx int) int
- func (a *Arr) MObj(idx int) *Obj
- func (a *Arr) MStr(idx int) string
- func (a *Arr) MUint32(idx int) uint32
- func (a *Arr) Obj(idx int) *Obj
- func (a *Arr) Put(idx int, v interface{}) *Arr
- func (a *Arr) Set(idx int, v interface{}) *Arr
- func (a *Arr) Str(idx int, nvl string) string
- func (a *Arr) Uint32(idx int, nvl uint32) uint32
- type BareArr
- type BareObj
- type IdxRangeError
- type IgnoreErrors
- type IndexError
- type KeyError
- type NoConversionError
- type Obj
- func (o *Obj) Arr(key string) *Arr
- func (o *Obj) Bool(key string, nvl bool) bool
- func (o *Obj) CArr(key string) (sub *Arr)
- func (o *Obj) CObj(key string) (sub *Obj)
- func (o *Obj) F32(key string, nvl float32) float32
- func (o *Obj) F64(key string, nvl float64) float64
- func (o *Obj) Ignoring(errs ...error) *Obj
- func (o *Obj) Int(key string, nvl int) int
- func (o *Obj) Int16(key string, nvl int16) int16
- func (o *Obj) Int32(key string, nvl int32) int32
- func (o *Obj) Int64(key string, nvl int64) int64
- func (o *Obj) Int8(key string, nvl int8) int8
- func (o *Obj) MArr(key string) *Arr
- func (o *Obj) MBool(key string) bool
- func (o *Obj) MF32(key string) float32
- func (o *Obj) MF64(key string) float64
- func (o *Obj) MInt(key string) int
- func (o *Obj) MInt16(key string) int16
- func (o *Obj) MInt32(key string) int32
- func (o *Obj) MInt64(key string) int64
- func (o *Obj) MInt8(key string) int8
- func (o *Obj) MObj(key string) (sub *Obj)
- func (o *Obj) MStr(key string) string
- func (o *Obj) MTime(key string) time.Time
- func (o *Obj) MUint16(key string) uint16
- func (o *Obj) MUint32(key string) uint32
- func (o *Obj) MUint64(key string) uint64
- func (o *Obj) MUint8(key string) uint8
- func (o *Obj) Obj(key string) (sub *Obj)
- func (o *Obj) Put(key string, v interface{}) *Obj
- func (o *Obj) Set(key string, v interface{}) *Obj
- func (o *Obj) Str(key, nvl string) string
- func (o *Obj) Time(key string, nvl time.Time) time.Time
- func (o *Obj) Uint16(key string, nvl uint16) uint16
- func (o *Obj) Uint32(key string, nvl uint32) uint32
- func (o *Obj) Uint64(key string, nvl uint64) uint64
- func (o *Obj) Uint8(key string, nvl uint8) uint8
- type SetError
- type TypeMismatch
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func Get ¶ added in v0.10.1
func Get(v interface{}, path ...interface{}) (interface{}, error)
Example ¶
package main
import (
"fmt"
"math"
"testing"
)
func printError(err error) {
fmt.Printf("ERROR: %s\n", err)
}
type onErr struct {
t *testing.T
}
func (oe onErr) error(err error) {
oe.t.Error(err)
}
func (oe onErr) fatal(err error) {
oe.t.Fatal(err)
}
func main() {
data := BareObj{
"foo": "bar",
"baz": BareArr{
true, false,
BareObj{"OK": math.Pi},
"end",
},
}
fmt.Println(Get(data, "baz", -2))
}
Output: map[OK:3.141592653589793] <nil>
Types ¶
type Arr ¶
type Arr struct {
Bare BareArr
// When OnError is nil all methods will panic on error, otherwise
// OnError(err) will be called. 'M*' methods returing values will return
// zero value on error if OnError has no non-local exists. Non-'M*' methods
// retrun the nvl value.
OnError func(error)
}
func (*Arr) CObj ¶
Example ¶
ggjaArr := Arr{OnError: printError}
objMbr3 := ggjaArr.CObj(3)
objMbr3.Put("name", "John Doe")
jStr, _ := json.Marshal(ggjaArr.Bare)
fmt.Println(string(jStr))
jStr, _ = json.Marshal(objMbr3.Bare)
fmt.Println(string(jStr))
Output: [null,null,null,{"name":"John Doe"}] {"name":"John Doe"}
type IdxRangeError ¶ added in v0.10.0
type IdxRangeError struct {
Begin, End int
}
func (IdxRangeError) Error ¶ added in v0.10.0
func (eir IdxRangeError) Error() string
type IgnoreErrors ¶ added in v0.10.0
func (IgnoreErrors) Error ¶ added in v0.10.0
func (ign IgnoreErrors) Error(err error)
type IndexError ¶ added in v0.10.0
type IndexError struct {
Idx, EIdx int
// contains filtered or unexported fields
}
func (IndexError) Error ¶ added in v0.10.0
func (ee IndexError) Error() string
func (IndexError) Unwrap ¶ added in v0.10.0
func (ee IndexError) Unwrap() error
type KeyError ¶ added in v0.10.0
type KeyError struct {
Key string
// contains filtered or unexported fields
}
type NoConversionError ¶ added in v0.10.1
type NoConversionError struct {
Value interface{}
Target string
}
func (NoConversionError) Error ¶ added in v0.10.1
func (nce NoConversionError) Error() string
type Obj ¶
type Obj struct {
Bare BareObj
// When OnError is nil all methods will panic on error, otherwise
// OnError(err) will be called. 'M*' methods returing values will return
// zero value on error if OnError has no non-local exists. Non-'M*' methods
// retrun the nvl value.
OnError func(error)
}
type TypeMismatch ¶ added in v0.10.0
type TypeMismatch struct {
Expect string
Value interface{}
}
func (TypeMismatch) Error ¶ added in v0.10.0
func (tmm TypeMismatch) Error() string
Source Files