Documentation
¶
Overview ¶
Package kv is for working with key-value pair files and strings often found in configuration files, environment variables, and other sources.
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
var ( // ErrInvalidTags is returned when the struct tags are invalid for kv. ErrInvalidTags = errors.New("invalid tags") // ErrInvalidObject is returned when the object is invalid to be a kv decoding target. ErrInvalidObject = errors.New("invalid object") // ErrStrict is returned when the decoder is in strict mode and an unknown key is encountered. ErrStrict = errors.New("strict mode") )
var ( // ErrSyntax is returned when the input string has a syntactical error. ErrSyntax = errors.New("syntax error") )
Functions ¶
func SplitRune ¶
SplitRune splits a string into a key and a value using the given separator. Quotes and escape characters are parsed in a similar manner to a shell. The separator is not included in the key or value. If the input string has a syntax error such as mismatched quotes or no delimiter, the error will be of type kv.ErrSyntax.
Example ¶
package main
import (
"fmt"
"github.com/k0sproject/rig/v2/kv"
)
func main() {
key, value, _ := kv.SplitRune(`key="value in quotes"`, '=')
fmt.Println("key:", key)
fmt.Println("value:", value)
}
Output: key: key value: value in quotes
Types ¶
type Decoder ¶
type Decoder struct {
// contains filtered or unexported fields
}
Decoder is a decoder for key-value pairs, similar to the encoding/json package. You can use struct tags to customize the decoding process.
The tag format is:
Field type `kv:"key_name,option1,option2"`.
The key_name is the key in the key-value pair.
- If the key is empty, the field name is used.
- If the key is '-', the field is ignored.
- If the key is '*' and the field is a map[string]string, it will catch all the keys that are not matched by the other tags.
The options are:
- ignorecase: the key is matched case-insensitively
- delim: when the field is a slice, the value is split by the specified delimiter. Default is ','.
Given a struct like this:
type Config struct {
Host string `kv:"host"`
Port int `kv:"port"`
Enabled bool `kv:"enabled"`
Options []string `kv:"options,delim=|"`
Extra map[string]string `kv:"*"`
}
And having data like this in config.txt:
host=10.0.0.1 port=8080 enabled=true options=opt1|opt2|opt3 hostname=example.com
Once decoded, you will get the Config fields set like this:
- Host: "10.0.0.1" (string)
- Port: 8080 (int)
- Enabled: true (bool). The values parsed as "true" for booleans are: "1", "true", "TRUE", "True", "on", "ON", "On", "yes", "YES", "Yes", "y" and "Y"
- Options: []string{"opt1", "opt2", "opt3"}
- Extra: map[string]string{"hostname": "example.com"}
Example ¶
package main
import (
"fmt"
"strings"
"github.com/k0sproject/rig/v2/kv"
)
func main() {
type testStruct struct {
Key1 string `kv:"key1"`
Key2 int `kv:"key2"`
Key3 []string `kv:"key3,delim:/"`
CatchAll map[string]string `kv:"*"`
}
target := testStruct{}
data := "key1=value1\nkey2=42\nkey3=foo/bar\nexample=example-catch-all"
decoder := kv.NewDecoder(strings.NewReader(data))
err := decoder.Decode(&target)
if err != nil {
fmt.Println(err)
}
fmt.Println("* Input data:")
fmt.Println(data)
fmt.Println()
fmt.Println("String value:", target.Key1)
fmt.Println("Int value:", target.Key2)
fmt.Println("Slice of strings:", target.Key3)
fmt.Println("Catch all:", target.CatchAll["example"])
}
Output: * Input data: key1=value1 key2=42 key3=foo/bar example=example-catch-all String value: value1 Int value: 42 Slice of strings: [foo bar] Catch all: example-catch-all
func NewDecoder ¶
NewDecoder returns a new decoder that reads from r.
func (*Decoder) CommentStart ¶
CommentStart sets the comment start string. If a line starts with the comment start string, it is ignored.
func (*Decoder) Decode ¶
Decode reads all of the key-value pairs from the input and stores them in the map or struct pointed to by obj.
func (*Decoder) FieldDelimiter ¶
FieldDelimiter sets the field delimiter. The default is '='.
func (*Decoder) RowDelimiter ¶
RowDelimiter sets the row delimiter. The default is '\n'.
Source Files