Refactor github.com/kubernetes/helm/pkg/strvals away

[mstoykov]

No description provided.

[na--]

Played with this some and came up with a simplistic but somewhat viable replacement: https://play.golang.org/p/6Y23Fyv8gO5

Copying it here, since I'm not sure if Go playground links are permanent:

package main

import (
	"fmt"
	"strconv"
	"strings"
)

func main() {
	dump(`test=mest,asdf=123, true=false`)
	dump(`we are pretty liberal = with what we support, even=" quoted strings with spaces  "`)
	dump(`noval,noval2=,noval3= , emptyval="",someval=wat`)
	dump(`test=mest,foo="bar",int=123,test=overwrite , float=3.14, sub.a=1, , sub.b=2, sub.c="Asdf"`)
	dump(`test=mest,test.sub=this is an error`)
}

func dump(s string) {
	res, err := strvals(s)
	fmt.Printf("err=%v, res=%#v\n", err, res)
}

func strvals(s string) (map[string]interface{}, error) {
	res := map[string]interface{}{}

	keyvals := strings.Split(s, ",")

	for _, kv := range keyvals {
		if len(kv) == 0 {
			continue
		}
		kvSplit := strings.SplitN(kv, "=", 2)
		if len(kvSplit) == 1 {
			kvSplit = append(kvSplit, "")
		}

		keyParts := strings.Split(strings.TrimSpace(kvSplit[0]), ".")
		resLevel := res

		for i := 0; i < len(keyParts)-1; i++ {
			if newLevel, ok := resLevel[keyParts[i]]; !ok {
				newLevel := map[string]interface{}{}
				resLevel[keyParts[i]] = newLevel
				resLevel = newLevel
			} else {
				if newLevelMap, ok := newLevel.(map[string]interface{}); ok {
					resLevel = newLevelMap
				} else {
					return nil, fmt.Errorf(
						"option '%s' was cannot be both %q and a map",
						strings.Join(keyParts[:i+1], "."), newLevel,
					)
				}
			}
		}

		resLevel[keyParts[len(keyParts)-1]] = getVal(strings.TrimSpace(kvSplit[1]))
	}

	return res, nil
}

func getVal(val string) interface{} {
	if val == "" {
		return nil
	} else if iVal, err := strconv.ParseInt(val, 10, 64); err == nil {
		return iVal
	} else if fVal, err := strconv.ParseFloat(val, 64); err == nil {
		return fVal
	} else if bVal, err := strconv.ParseBool(val); err == nil {
		return bVal
	} else if len(val) >= 2 && val[0] == '"' && val[len(val)-1] == '"' {
		return val[1 : len(val)-1]
	} else {
		return val
	}
}

running it will produce:

err=<nil>, res=map[string]interface {}{"asdf":123, "test":"mest", "true":false}
err=<nil>, res=map[string]interface {}{"even":" quoted strings with spaces  ", "we are pretty liberal":"with what we support"}
err=<nil>, res=map[string]interface {}{"emptyval":"", "noval":interface {}(nil), "noval2":interface {}(nil), "noval3":interface {}(nil), "someval":"wat"}
err=<nil>, res=map[string]interface {}{"":interface {}(nil), "float":3.14, "foo":"bar", "int":123, "sub":map[string]interface {}{"a":1, "b":2, "c":"Asdf"}, "test":"overwrite"}
err=option 'test' was cannot be both "mest" and a map, res=map[string]interface {}(nil)

[mstoykov]

This is a requirement to drop gopkg.in/yaml.v2 (we still will have the v3).

In addition, we need to drop it from some 2 places in our code base and drop github.com/zyedidia/highlight as it also uses the v2 and there are no updates that will replace it with something else.

This in total drops around 12k LOC.

On the other side the kafka output is making a lot of use of it to a point that redoing it is probably not ... possible. But the other places we use it (influxdb and --dns cli argument) are probably not using all the strvals functionality

[na--]

I'll close this issue because we no longer depend on strvals in k6 after #2270 🎉 That said, we have hand-crafted a bunch of poor replacements in the few places where we need something like it... It will be much simpler and less error prone to have that type of config parsing to be done by a config library... So I opened grafana/croconf#16, which we'll hopefully get around to again soon 🤞