mitchellh/hashstructure

Two different contents of same struct give the same hash

jerome-laforge opened this issue · 3 comments

jerome-laforge commented

Hello,
I have the same hash with this:

package main

import (
	"fmt"

	"github.com/mitchellh/hashstructure"
)

type bar struct {
	stuf string
}

type foobarbar map[string][4][]string

type (
	foo []bar
)

type cacheData struct {
	foobar  foo
	foobar1 foobarbar
}

func main() {

	{
		hash, err := hashstructure.Hash(cacheData{}, nil)
		if err != nil {
			panic(err)
		}

		fmt.Println(hash) // => 9141985097084809465
	}

	{
		hash, err := hashstructure.Hash(cacheData{
			foobar1: foobarbar{
				"hello": [4][]string{[]string{"world"}, nil, nil, nil},
			},
		}, nil)
		if err != nil {
			panic(err)
		}

		fmt.Println(hash) // => 9141985097084809465 !!!! this the same of hashstructure.Hash(cacheData{}, nil)
	}

}
go version
go version go1.7.5 linux/amd64

go env

go env
GOARCH="amd64"
GOBIN=""
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/johndoe/go"
GORACE=""
GOROOT="/usr/lib/go"
GOTOOLDIR="/usr/lib/go/pkg/tool/linux_amd64"
CC="gcc"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build521523302=/tmp/go-build -gno-record-gcc-switches"
CXX="g++"
CGO_ENABLED="1"
jerome-laforge commented

Ok, I found the pb.
the visibility of foobar & foobar1.
Sorry for the noise...

rashmichandrashekar commented

Ok, I found the pb. the visibility of foobar & foobar1. Sorry for the noise...

@jerome-laforge - I am seeing a similar problem when I am trying to create a hash for 2 prometheus configs specifially for the regex field. What was the fix for your issue?
cfg1 -
scrape_configs:
- job_name: kube-proxy
scrape_interval: 30s
label_limit: 63
label_name_length_limit: 511
label_value_length_limit: 1023
kubernetes_sd_configs:
- role: pod
relabel_configs:
- action: keep
source_labels:
- __meta_kubernetes_namespace
- __meta_kubernetes_pod_name
separator: "/"
regex: kube-system/kube-proxy.+
- source_labels:
- address
action: replace
target_label: address
regex: "regex1"
replacement: "$$1:10249"

cfg1 -
scrape_configs:
- job_name: kube-proxy
scrape_interval: 30s
label_limit: 63
label_name_length_limit: 511
label_value_length_limit: 1023
kubernetes_sd_configs:
- role: pod
relabel_configs:
- action: keep
source_labels:
- __meta_kubernetes_namespace
- __meta_kubernetes_pod_name
separator: "/"
regex: kube-system/kube-proxy.+
- source_labels:
- address
action: replace
target_label: address
regex: "regex2"
replacement: "$$1:10249"