gosample

GO Sample | Cloudfoundry

This is a simple app created to work and show the capabilities of golang when deployed to Cloudfoundry.

Intended (but not limited) to be used with pcf-dev. This project also assumes that you have a functional version of golang.

First push

All you have to do is to clone this repo and then move to it and run:

$ go get -u github.com/lcacciagioni/gosample
$ cd $GOPATH/src/github.com/lcacciagioni/gosample
$ cf push
Using manifest file $GOPATH/src/github.com/lcacciagioni/gosample/manifest.yml
Updating app gosample in org pcfdev-org / space pcfdev-space as user...
OK

Uploading gosample...
Uploading app files from: $GOPATH/src/github.com/lcacciagioni/gosample
Uploading 22K, 25 files

                             
Done uploading
OK

Stopping app gosample in org pcfdev-org / space pcfdev-space as user...
OK

Starting app gosample in org pcfdev-org / space pcfdev-space as user...
Downloading dotnet-core_buildpack...
Downloading java_buildpack...
Downloading ruby_buildpack...
Downloading nodejs_buildpack...
Downloading go_buildpack...
Downloaded nodejs_buildpack
Downloading python_buildpack...
Downloaded ruby_buildpack
Downloading php_buildpack...
Downloaded java_buildpack
Downloading staticfile_buildpack...
Downloaded dotnet-core_buildpack
Downloading binary_buildpack...
Downloaded go_buildpack
Downloaded php_buildpack
Downloaded python_buildpack
Downloaded binary_buildpack
Downloaded staticfile_buildpack
Creating container
Successfully created container
Downloading app package...
Downloaded app package (21.5K)
Downloading build artifacts cache...
Downloaded build artifacts cache (66.6M)
Staging...
-------> Buildpack version 1.7.15
file:///tmp/buildpacks/4351f5cc91c6d5bb8d11a7418ea9cbff/dependencies/https___buildpacks.cloudfoundry.org_concourse-binaries_godep_godep-v75-linux-x64.tgz
file:///tmp/buildpacks/4351f5cc91c6d5bb8d11a7418ea9cbff/dependencies/https___buildpacks.cloudfoundry.org_concourse-binaries_glide_glide-v0.12.3-linux-x64.tgz
-----> Checking Godeps/Godeps.json file.
-----> Using go1.7.3
Installing package '.' (default)
-----> Running: go install -v -tags cloudfoundry . 
github.com/lcacciagioni/gosample/vendor/github.com/mitchellh/mapstructure
github.com/lcacciagioni/gosample/vendor/github.com/cloudfoundry-community/go-cfenv
github.com/lcacciagioni/gosample
Exit status 0
Staging complete
Uploading droplet, build artifacts cache...
Uploading build artifacts cache...
Uploading droplet...
Uploaded build artifacts cache (66.5M)
Uploaded droplet (2M)
Uploading complete
Destroying container
Successfully destroyed container

2 of 2 instances running

App started


OK

App gosample was started using this command `gosample`

Showing health and status for app gosample in org pcfdev-org / space pcfdev-space as user...
OK

requested state: started
instances: 2/2
usage: 32M x 2 instances
urls: gosample.local.pcfdev.io
last uploaded: Wed Jan 25 14:06:34 UTC 2017
stack: cflinuxfs2
buildpack: Go

     state     since                    cpu    memory        disk          details
#0   running   2017-01-25 03:07:05 PM   0.0%   2.4M of 32M   7.2M of 64M
#1   running   2017-01-25 03:07:05 PM   0.0%   2.7M of 32M   7.2M of 64M

It will use the default manifest with almost no requirements as you can see. Now if you do: $ curl gosample.local.pcfdev.io you will gonna be able to see something like:

Hello, World! from GO

Complete Environment: 

 [CF_INSTANCE_ADDR=10.0.2.15:60200 TMPDIR=/home/vcap/tmp USER=vcap VCAP_APPLICATION={"application_id":"e78e2dd4-8e0a-4ab9-9cd0-38b63ea72dc5","application_name":"gosample","application_uris":["gosample.local.pcfdev.io"],"application_version":"aac0a29b-6bfb-48f3-bd95-9f72c7aca9f2","cf_api":"http://api.local.pcfdev.io","host":"0.0.0.0","instance_id":"3a59e422-e25d-48c5-7b1a-3dc1279690e6","instance_index":1,"limits":{"disk":64,"fds":16384,"mem":32},"name":"gosample","port":8080,"space_id":"0f9dede9-6eab-496f-a39c-8b419e1d2f9f","space_name":"pcfdev-space","uris":["gosample.local.pcfdev.io"],"version":"aac0a29b-6bfb-48f3-bd95-9f72c7aca9f2"} CF_INSTANCE_GUID=3a59e422-e25d-48c5-7b1a-3dc1279690e6 PATH=/usr/local/bin:/usr/bin:/bin:/home/vcap/app/bin PWD=/home/vcap/app LANG=en_US.UTF-8 CF_INSTANCE_PORT=60200 VCAP_SERVICES={} CF_INSTANCE_IP=10.0.2.15 CF_INSTANCE_INDEX=1 HOME=/home/vcap/app SHLVL=1 CF_INSTANCE_PORTS=[{"external":60200,"internal":8080},{"external":60201,"internal":2222}] INSTANCE_INDEX=1 PORT=8080 INSTANCE_GUID=3a59e422-e25d-48c5-7b1a-3dc1279690e6 MEMORY_LIMIT=32m _=/home/vcap/app/bin/gosample]

Super I'm running in CloudFoundry and this are my variables:
ID: 3a59e422-e25d-48c5-7b1a-3dc1279690e6
Index: 1
Name: gosample
Host: 0.0.0.0
Port: 8080
Version: aac0a29b-6bfb-48f3-bd95-9f72c7aca9f2
Home: /home/vcap/app
MemoryLimit: 32m
WorkingDir: /home/vcap/app
TempDir: /home/vcap/tmp
User: vcap

MYSQL: false

RABBITMQ: false

REDIS: false

Docker way

The only thing that really changes from the previous deployment way is how you tell CloudFoundry to deploy your code so do all the same as before except for the cf push command which is changed by:

cf push gosample -o cacciald/gosample:latest

The docker image must be pushed before to a docker secure repo. For more information, please read this.

The image used here is built and updated from this same repo and lives in docker hub.

WARNING: Don't desperate yourself docker images seems to be A LOT SLOWERS than buildpacks to deploy but they work in the end.

Enabling Services

In the next few lines I'll try to show you how to enable the different services to see some of the exposed variables using also curl.

RabbitMQ

Execute this commands to have rabbitmq env vars in place.

$ cf cs p-rabbitmq standard rabbitmq
$ cf bs gosample rabbitmq
$ cf restage gosample

After doing this a new section will appear when you do $ curl gosample.local.pcfdev.io with something similar to this:

RABBITMQ: true

AMQP: 
        host:  rabbitmq.local.pcfdev.io
        port:  5672
        user:  48c41519-20bb-433b-b477-a6a228c8f463
        pass:  vh2plek65pskf61c67evnu9bgs
        vhost:  0ff2794f-f17d-40ef-8c3e-081c76c1fd9b
        ssl:  false

MGMT: 
        host:  rabbitmq.local.pcfdev.io
        port:  15672
        user:  48c41519-20bb-433b-b477-a6a228c8f463
        pass:  vh2plek65pskf61c67evnu9bgs
        ssl:  false

MySql

Execute this commands to have mysql env vars in place.

$ cf cs p-mysql 1gb mysql
$ cf bs gosample mysql
$ cf restage gosample

And then the MySql section will appear with something similar to this:

MYSQL: true

DB Host:  mysql-broker.local.pcfdev.io
DB Port:  3306
DB Name:  cf_7f27f3fe_5f38_4f3f_be18_3c50dad5458a
DB User:  eRhRJwVDmH3Ah4Us
DB Pass:  Yc9Py9Llux4uTs38

Redis

Execute this commands to have redis env vars in place.

$ cf cs p-redis shared-vm redis
$ cf bs gosample redis
$ cf restage gosample

And then the Redis section will appear with something similar to this:

REDIS: true

Host:  redis.local.pcfdev.io
Pass:  8e8d56ff-b0d9-4f59-b7de-790012711aef

VERSIONS

go: go version go1.7.4 linux/amd64
glide: glide version v0.12.3
pcf-dev: PCF Dev version 0.23.0 (CLI: 474b3ba, OVA: 0.436.0)
cf cli: cf version 6.23.1+a70deb3.2017-01-13

Available marketplace

Getting services from marketplace in org pcfdev-org / space pcfdev-space as user...
OK

service        plans             description
local-volume   free-local-disk   Local service docs: https://github.com/cloudfoundry-incubator/local-volume-release/
p-mysql        512mb, 1gb        MySQL databases on demand
p-rabbitmq     standard          RabbitMQ is a robust and scalable high-performance multi-protocol messaging broker.
p-redis        shared-vm         Redis service to provide a key-value store

TIP:  Use 'cf marketplace -s SERVICE' to view descriptions of individual plans of a given service.

TODO

• Create a Docker Image with same code (Prove docker workflow)
• Do something using Rabbit
• Do something using MySql
• Do Something using Redis