I will mostly be following the instructions from here, but instead of Ubuntu I am going to try CentOS.
Getting Started
All you will need to start, aside from the obvious internet connection, is a Digital Ocean account. I’ve found that the $5/mo. plan is really good for learning.
Spin up your droplet
This is actually pretty straightforward. Your regional preferences may differ, but here are what my settings looked like:
You’ll immediately see a progress bar to show you how quickly the droplet is being started:
Actually, it took less than 60 seconds total to completely spin that up. This is my first experience with Digital Ocean, so I’m pretty impressed with that.
Once the droplet is up and running, you will receive an email similar to this one, that will include your login credentials:
Yes, that is Google Inbox. It’s shiny, right?
Use these to SSH into your new droplet:
$ ssh digital-ocean
The authenticity of host '[address] ([address])' can't be established.
RSA key fingerprint is [key].
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '[address]' (RSA) to the list of known hosts.
[email protected][address]'s password:
You are required to change your password immediately (root enforced)
Changing password for root.
(current) UNIX password:
New password:
Retype new password:
[[email protected] ~]#
(Note that I updated my ~/.ssh/config file to include the hostname and user name for this droplet and provided it the alias digital-ocean. If you do not do this, then you can simply SSH into the address provided in the credentials email.)
Create a new user
According to the Ubuntu instructions provided, the next step is to create a new user account. Pretty straightforward, but since the commands are a little different for CentOS7, I am using Digital Ocean’s Initial Server Setup with CentOS 7 instructions. Here I am creating a new user, providing that user with superuser privileges, and changing accounts into the new user account:
[[email protected] ~]# adduser quinn
[[email protected] ~]# passwd quinn
Changing password for user quinn.
New password:
Retype new password:
passwd: all authentication tokens updated successfully.
[[email protected] ~]# gpasswd -a quinn wheel
Adding user quinn to group wheel
[[email protected] ~]# su quinn
[[email protected] root]$
To create your own user, simply replace quinn with your desired username.
Installing Go
The Ubuntu instructions use apt-get for this, but CentOS does not have apt-get available. But we’re in luck! We can just run sudo yum install golang (or run the command as root) to install the latest release of Go (yes, there is a lot of output):
[[email protected] root]$ sudo yum install golang
We trust you have received the usual lecture from the local System
Administrator. It usually boils down to these three things:
#1) Respect the privacy of others.
#2) Think before you type.
#3) With great power comes great responsibility.
[sudo] password for quinn:
Loaded plugins: fastestmirror
base | 3.6 kB 00:00
extras | 3.4 kB 00:00
updates | 3.4 kB 00:00
(1/4): extras/7/x86_64/primary_db | 35 kB 00:00
(2/4): base/7/x86_64/group_gz | 157 kB 00:00
(3/4): updates/7/x86_64/primary_db | 4.8 MB 00:01
(4/4): base/7/x86_64/primary_db | 4.9 MB 00:01
Determining fastest mirrors
* base: mirror.ash.fastserv.com
* extras: mirrors.advancedhosters.com
* updates: mirrors.lga7.us.voxel.net
Resolving Dependencies
--> Running transaction check
---> Package golang.x86_64 0:1.3.3-1.el7.centos will be installed
--> Processing Dependency: golang-src for package: golang-1.3.3-1.el7.centos.x86_64
--> Processing Dependency: golang-bin for package: golang-1.3.3-1.el7.centos.x86_64
--> Running transaction check
---> Package golang-pkg-bin-linux-amd64.x86_64 0:1.3.3-1.el7.centos will be installed
--> Processing Dependency: golang-pkg-linux-amd64 = 1.3.3-1.el7.centos for package: golang-pkg-bin-linux-amd64-1.3.3-1.el7.centos.x86_64
--> Processing Dependency: golang-pkg-linux-amd64 = 1.3.3-1.el7.centos for package: golang-pkg-bin-linux-amd64-1.3.3-1.el7.centos.x86_64
--> Processing Dependency: gcc for package: golang-pkg-bin-linux-amd64-1.3.3-1.el7.centos.x86_64
---> Package golang-src.noarch 0:1.3.3-1.el7.centos will be installed
--> Running transaction check
---> Package gcc.x86_64 0:4.8.2-16.2.el7_0 will be installed
--> Processing Dependency: cpp = 4.8.2-16.2.el7_0 for package: gcc-4.8.2-16.2.el7_0.x86_64
--> Processing Dependency: glibc-devel >= 2.2.90-12 for package: gcc-4.8.2-16.2.el7_0.x86_64
--> Processing Dependency: libmpfr.so.4()(64bit) for package: gcc-4.8.2-16.2.el7_0.x86_64
--> Processing Dependency: libmpc.so.3()(64bit) for package: gcc-4.8.2-16.2.el7_0.x86_64
---> Package golang-pkg-linux-amd64.noarch 0:1.3.3-1.el7.centos will be installed
--> Running transaction check
---> Package cpp.x86_64 0:4.8.2-16.2.el7_0 will be installed
---> Package glibc-devel.x86_64 0:2.17-55.el7_0.1 will be installed
--> Processing Dependency: glibc-headers = 2.17-55.el7_0.1 for package: glibc-devel-2.17-55.el7_0.1.x86_64
--> Processing Dependency: glibc-headers for package: glibc-devel-2.17-55.el7_0.1.x86_64
---> Package libmpc.x86_64 0:1.0.1-3.el7 will be installed
---> Package mpfr.x86_64 0:3.1.1-4.el7 will be installed
--> Running transaction check
---> Package glibc-headers.x86_64 0:2.17-55.el7_0.1 will be installed
--> Processing Dependency: kernel-headers >= 2.2.1 for package: glibc-headers-2.17-55.el7_0.1.x86_64
--> Processing Dependency: kernel-headers for package: glibc-headers-2.17-55.el7_0.1.x86_64
--> Running transaction check
---> Package kernel-headers.x86_64 0:3.10.0-123.9.3.el7 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
================================================================================
Package Arch Version Repository Size
================================================================================
Installing:
golang x86_64 1.3.3-1.el7.centos extras 2.6 M
Installing for dependencies:
cpp x86_64 4.8.2-16.2.el7_0 updates 5.9 M
gcc x86_64 4.8.2-16.2.el7_0 updates 16 M
glibc-devel x86_64 2.17-55.el7_0.1 updates 1.0 M
glibc-headers x86_64 2.17-55.el7_0.1 updates 650 k
golang-pkg-bin-linux-amd64 x86_64 1.3.3-1.el7.centos extras 11 M
golang-pkg-linux-amd64 noarch 1.3.3-1.el7.centos extras 6.6 M
golang-src noarch 1.3.3-1.el7.centos extras 5.5 M
kernel-headers x86_64 3.10.0-123.9.3.el7 updates 1.4 M
libmpc x86_64 1.0.1-3.el7 base 51 k
mpfr x86_64 3.1.1-4.el7 base 203 k
Transaction Summary
================================================================================
Install 1 Package (+10 Dependent packages)
Total download size: 51 M
Installed size: 181 M
Is this ok [y/d/N]: y
Downloading packages:
(1/11): cpp-4.8.2-16.2.el7_0.x86_64.rpm | 5.9 MB 00:01
(2/11): gcc-4.8.2-16.2.el7_0.x86_64.rpm | 16 MB 00:02
(3/11): glibc-devel-2.17-55.el7_0.1.x86_64.rpm | 1.0 MB 00:01
(4/11): glibc-headers-2.17-55.el7_0.1.x86_64.rpm | 650 kB 00:00
(5/11): kernel-headers-3.10.0-123.9.3.el7.x86_64.rpm | 1.4 MB 00:00
(6/11): golang-1.3.3-1.el7.centos.x86_64.rpm | 2.6 MB 00:00
(7/11): libmpc-1.0.1-3.el7.x86_64.rpm | 51 kB 00:00
(8/11): golang-pkg-bin-linux-amd64-1.3.3-1.el7.centos.x86_ | 11 MB 00:01
(9/11): mpfr-3.1.1-4.el7.x86_64.rpm | 203 kB 00:00
(10/11): golang-src-1.3.3-1.el7.centos.noarch.rpm | 5.5 MB 00:01
(11/11): golang-pkg-linux-amd64-1.3.3-1.el7.centos.noarch. | 6.6 MB 00:06
--------------------------------------------------------------------------------
Total 5.5 MB/s | 51 MB 00:09
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : mpfr-3.1.1-4.el7.x86_64 1/11
Installing : libmpc-1.0.1-3.el7.x86_64 2/11
Installing : cpp-4.8.2-16.2.el7_0.x86_64 3/11
Installing : kernel-headers-3.10.0-123.9.3.el7.x86_64 4/11
Installing : glibc-headers-2.17-55.el7_0.1.x86_64 5/11
Installing : glibc-devel-2.17-55.el7_0.1.x86_64 6/11
Installing : gcc-4.8.2-16.2.el7_0.x86_64 7/11
Installing : golang-src-1.3.3-1.el7.centos.noarch 8/11
Installing : golang-pkg-linux-amd64-1.3.3-1.el7.centos.noarch 9/11
Installing : golang-1.3.3-1.el7.centos.x86_64 10/11
Installing : golang-pkg-bin-linux-amd64-1.3.3-1.el7.centos.x86_64 11/11
Verifying : cpp-4.8.2-16.2.el7_0.x86_64 1/11
Verifying : golang-pkg-bin-linux-amd64-1.3.3-1.el7.centos.x86_64 2/11
Verifying : golang-1.3.3-1.el7.centos.x86_64 3/11
Verifying : gcc-4.8.2-16.2.el7_0.x86_64 4/11
Verifying : golang-src-1.3.3-1.el7.centos.noarch 5/11
Verifying : kernel-headers-3.10.0-123.9.3.el7.x86_64 6/11
Verifying : glibc-devel-2.17-55.el7_0.1.x86_64 7/11
Verifying : mpfr-3.1.1-4.el7.x86_64 8/11
Verifying : glibc-headers-2.17-55.el7_0.1.x86_64 9/11
Verifying : libmpc-1.0.1-3.el7.x86_64 10/11
Verifying : golang-pkg-linux-amd64-1.3.3-1.el7.centos.noarch 11/11
Installed:
golang.x86_64 0:1.3.3-1.el7.centos
Dependency Installed:
cpp.x86_64 0:4.8.2-16.2.el7_0
gcc.x86_64 0:4.8.2-16.2.el7_0
glibc-devel.x86_64 0:2.17-55.el7_0.1
glibc-headers.x86_64 0:2.17-55.el7_0.1
golang-pkg-bin-linux-amd64.x86_64 0:1.3.3-1.el7.centos
golang-pkg-linux-amd64.noarch 0:1.3.3-1.el7.centos
golang-src.noarch 0:1.3.3-1.el7.centos
kernel-headers.x86_64 0:3.10.0-123.9.3.el7
libmpc.x86_64 0:1.0.1-3.el7
mpfr.x86_64 0:3.1.1-4.el7
Complete!
Now the moment of truth:
[[email protected] root]$ go version
go version go1.3.3 linux/amd64
Awesome.
Environmental Variables
If you check your environmental variables, you will see that references to Go are "mysteriously" missing:
[[email protected] root]$ echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin
[[email protected] root]$ echo $GOPATH
[[email protected] root]$
In CentOS you have a ~/.bash_profile file that you can update to handle this. By default, it will look a little something like this:
# .bash_profile
# Get the aliases and functions
if [ -f ~/.bashrc ]; then
. ~/.bashrc
fi
# User specific environment and startup programs
PATH=$PATH:$HOME/.local/bin:$HOME/bin
export PATH
Update the file to include $GOPATH and make sure to append the bin subdirectory of your $GOPATH to your $PATH variable:
export GOPATH=$HOME/go
PATH=$PATH:$HOME/.local/bin:$HOME/bin:$GOPATH/bin
After you source your ~/.bash_profile file, you should now have the appropriate values for these variables:
[[email protected] root]$ source ~/.bash_profile
[[email protected] root]$ echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin:/home/quinn/.local/bin:/home/quinn/bin:/home/quinn/go/bin
[[email protected] root]$ echo $GOPATH
/home/quinn/go
Excellent.
Note: You can also see all of your Go environment information using go env:
[[email protected] bin]$ go env
GOARCH="amd64"
GOBIN=""
GOCHAR="6"
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/quinn/go"
GORACE=""
GOROOT="/usr/lib/golang"
GOTOOLDIR="/usr/lib/golang/pkg/tool/linux_amd64"
CC="gcc"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0"
CXX="g++"
CGO_ENABLED="1"
Installing Git & Mercurial
In order to "get" revel (next step) we need both git and hg (Mercurial). To install, simply run:
[[email protected] ~]$ sudo yum install git
[[email protected] ~]$ sudo yum install hg
For brevity, I am not including the output. The install is actually very speedy (rock on Digital Ocean!), but there were a lot of dependencies in both cases.
Sidenote: How to determine if you need Git, Hg, or both
For me, it was a case of trial and error. When I attempted to "get" revel with out both Git and Hg, I received an error that I did not have the other package. i.e. When I only had git, I received the error go: missing Mercurial command. Likewise when I only had Hg, I received the error go: missing Git command.
Installing EPEL
You will also need EPEL. To install, I followed these instructions.
[[email protected] ~]$ cd /tmp
[[email protected] tmp]$ sudo yum install wget
[[email protected] tmp]$ wget https://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-2.noarch.rpm
Again, for brevity, I have not included the install output.
Sidenote: yum install method
I also tried sudo yum install epel-release-7-2.noarch.rpm, but received the following message: No package epel-release-7-2.noarch.rpm available.
Installing Revel
To install Revel we need to use go get. Good thing we installed git and hg, eh?
[[email protected] tmp]$ go get github.com/revel/cmd/revel
(If all goes smoothly, you should have no output.)
Now for the moment of truth:
[[email protected] tmp]$ revel run github.com/revel/revel/samples/chat
~
~ revel! http://revel.github.io
~
2014/12/03 21:10:19 revel.go:326: Loaded module static
2014/12/03 21:10:19 revel.go:326: Loaded module testrunner
2014/12/03 21:10:19 run.go:57: Running chat (github.com/revel/revel/samples/chat) in dev mode
2014/12/03 21:10:19 harness.go:165: Listening on :9000
SUCCESS.
Addenda
go getuses the same type of version control system as the package that you are "getting".- As a new user to CentOS I am still not 100% clear what EPEL provides for the revel install – however without it you will be plagued with errors.
Spread the word
