Nos

A bash library and framework to expedite Nanobox engine development.

Installation

No installation is required, Nanobox build containers have Nos pre-installed.

Usage

To use Nos, simply source the common.sh script and initialize the framework.

#!/bin/bash

# source the Nos framework
. /opt/nos/common.sh

# initialize Nos with the original arguments
nos_init $@

For an overview of how and when to use Nos, please refer to the Nanobox Common Tasks guide.

API

• Payload
  • nos_payload
• Validation
  • nos_validate_presence
  • nos_validate_in
  • nos_validate_not_in
• Printing Output
  • nos_print_process_start
  • nos_print_process_end
  • nos_print_bullet
  • nos_print_bullet_info
  • nos_print_bullet_sub
  • nos_print_warning
  • nos_print_fatal
  • nos_print_block
• Installing Packages
  • nos_install
  • nos_uninstall
• Running Commands
  • nos_run_process
• Environment Variables
  • nos_set_evar
  • nos_persist_evar
• Templates
  • nos_template
  • nos_template_file

Payload

nos_payload(1)

$1 = key

A simple getter for fetching a payload value

Validation

nos_validate_presence(1)

$1 = field

Validate that a field exists within the boxfile payload and has a value.
If the check fails, a fatal error will be printed an a non-zero exit
will be forced.

nos_validate_in(2)

$1 = field
$2 = possible values

Validates that if a field exists, the value present falls within a range
of acceptable options.

nos_validate_not_in(2)

$1 = field
$2 = possible values

Validates that if a field exists, the value present falls does not fall
within a range of options.

Printing Output

nos_print_header(1)

$1 = label

Print a header, formatted to 70 characters, with the label

Example:

nos_print_header "headline here"

would produce:
::::::::::::::::::::::::::: HEADLINE HERE :::::::::::::::::::::::::::

nos_print_process_start(1)

$1 = label

Print a header indicating the start of a process.

Example:

nos_print_process_start "installing ruby-2.2"

would produce:
INSTALLING RUBY-2.2 ------------------------------------------------>

nos_print_process_end()

Creates a hard delineation after a process

nos_print_bullet(1)

$1 = message

Print a line item in the form of a bullet point

Example:

nos_print_bullet "Language Detected : Ruby"

would produce:
+ Language Detected : Ruby

nos_print_bullet_info(1)

$1 = message

Print a line item as followup info to a bullet point

Example:

nos_print_bullet_info "Language Detected : Ruby"

would produce:
 Language Detected : Ruby

nos_print_bullet_sub(1)

$1 = message

Print a line item as a sub or followup item to a bullet point

Example:

nos_print_bullet_sub "Language Detected : Ruby"

would produce:
  - Language Detected : Ruby

nos_print_warning(1)

$1 = message

Print a warning message, formatted to a 70 character block paragraph

Example:

nos_print_warning "We've detected you may be using... (abbreviated for clarity)"

would produce:
-----------------------------  WARNING  -----------------------------
We've detected you may be using sessions in a way that could cause
unexpected behavior. Feel free to review the following guide for
more information : bit.ly/2sA9b

nos_print_fatal(2)

$1 = title
$2 = message

Example:

nos_print_fatal "deploy stream disconnected", "Oh snap... (abbreviated for clarity)"

would produce:
! DEPLOY STREAM DISCONNECTED !

Oh snap the deploy stream just disconnected. No worries, you can
visit the dashboard to view the complete output stream.

nos_print_block(1)

$1 = message

Print a message formatted as a block of text, wrapped at 70 characters

Example:

nos_print_block "We've detected you may be using... (abbreviated for clarity)"

would produce:
We've detected you may be using sessions in a way that could cause
unexpected behavior. Feel free to review the following guide for
more information : bit.ly/2sA9b

Installing Packages

nos_install(1)

$1 = package name

A simple expressive shortcut to install a pkgsrc package via pkgin

nos_uninstall(1)

$1 = package name

A simple expressive shortcut to uninstall a pkgsrc package via pkgin

Running Commands

nos_run_process(2)

$1 = process label
$2 = command

A helper to run a process and format the output according to the styleguide

nos_run_subprocess(2)

$1 = process label
$2 = command

A helper to run a subprocess and format the output according to the styleguide

Environment Variables

nos_set_evar(2)

$1 = key
$2 = value

Sets an environment variable in the running process

nos_persist_evar(2)

$1 = key
$2 = value

Persists an environment variable which will be available to the process that
the code runs in after a successful deploy.

Templates

nos_template(3)

$1 = source
$2 = destination
$3 = JSON|YAML payload

Renders a mustache template from the templates directory and persists the
result at (destination). The payload provided is passed to mustache.

nos_template_file(2)

$1 = source
$2 = destination

Copies a file from the files directory to the specified destination.