Etc Hosts Management Utility & Go Library
/etc/hosts Management
It is easy to open your /etc/hosts file in text editor and add or remove entries. However, if you make heavy use of /etc/hosts for software development or DevOps purposes, it can sometimes be difficult to automate and validate large numbers of host entries.
txeh was initially built as a golang library to support kubefwd, a Kubernetes port-forwarding utility utilizing /etc/hosts heavily, to associate custom hostnames with multiple local loopback IP addresses and remove these entries when it terminates.
A computer's /etc/hosts file is a powerful utility for developers and system administrators to create localized, custom DNS entries. This small go library and utility were developed to encapsulate the complexity of working with /etc/hosts directly by providing a simple interface for adding and removing entries in a /etc/hosts file.
txeh Utility
Install
MacOS homebrew users can brew install txn2/tap/txeh, otherwise see releases for packages and binaries for a number of distros and architectures including Windows, Linux and Arm based systems.
Complie and run from source (dependencies are vendored):
go run ./util/txeh.go
Use
The txeh CLI application allows command line or scripted access to /etc/hosts file modification.
Example CLI Usage:
_ _
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| __\ \/ / _ \ '_ \
| |_ > < __/ | | |
\__/_/\_\___|_| |_| v1.1.0
Add, remove and re-associate hostname entries in your /etc/hosts file.
Read more including useage as a Go library at https://github.com/txn2/txeh
Usage:
txeh [flags]
txeh [command]
Available Commands:
add Add hostnames to /etc/hosts
help Help about any command
remove Remove a hostname or ip address
version Print the version number of txeh
Flags:
-d, --dryrun dry run, output to stdout (ignores quiet)
-h, --help help for txeh
-q, --quiet no output
-r, --read string (override) Path to read /etc/hosts file.
-w, --write string (override) Path to write /etc/hosts file.
# point the hostnames "test" and "test.two" to the local loopback
sudo txeh add 127.0.0.1 test test.two
# remove the hostname "test"
sudo txeh remove host test
# remove multiple hostnames
sudo txeh remove host test test2 test.two
# remove an IP address and all the hosts that point to it
sudo txeh remove ip 93.184.216.34
# remove multiple IP addresses
sudo txeh remove ip 93.184.216.34 127.1.27.1
# remove CIDR ranges
sudo txeh remove cidr 93.184.216.0/24 127.1.27.0/28
# quiet mode will suppress output
sudo txeh remove ip 93.184.216.34 -q
# dry run will print a rendered /etc/hosts with your changes without
# saving it.
sudo txeh remove ip 93.184.216.34 -d
# use quiet mode and dry-run to direct the rendered /etc/hosts file
# to another file
sudo txeh add 127.1.27.100 dev.example.com -q -d > hosts.test
# specify an alternate /etc/hosts file to read. writing will
# default to the specified read path.
txeh add 127.1.27.100 dev2.example.com -q -r ./hosts.test
# specify a seperate read and write oath
txeh add 127.1.27.100 dev3.example.com -r ./hosts.test -w ./hosts.test2
txeh Go Library
Dependency:
go get github.com/txn2/txeh
Example Golang Implementation:
package main
import (
"fmt"
"strings"
"github.com/txn2/txeh"
)
func main() {
hosts, err := txeh.NewHostsDefault()
if err != nil {
panic(err)
}
hosts.AddHost("127.100.100.100", "test")
hosts.AddHost("127.100.100.101", "logstash")
hosts.AddHosts("127.100.100.102", []string{"a", "b", "c"})
hosts.RemoveHosts([]string{"example", "example.machine", "example.machine.example.com"})
hosts.RemoveHosts(strings.Fields("example2 example.machine2 example.machine.example.com2"))
hosts.RemoveAddress("127.1.27.1")
removeList := []string{
"127.1.27.15",
"127.1.27.14",
"127.1.27.13",
}
hosts.RemoveAddresses(removeList)
hfData := hosts.RenderHostsFile()
// if you like to see what the outcome will
// look like
fmt.Println(hfData)
hosts.Save()
// or hosts.SaveAs("./test.hosts")
}
Build Release
Build test release:
goreleaser --skip-publish --rm-dist --skip-validate
Build and release:
GITHUB_TOKEN=$GITHUB_TOKEN goreleaser --rm-dist
License
Apache License 2.0
