nuv

WARNING: this is still work in progress

The code may not build, there can be errors that will destroy your hard disk and so on.

Also documentation and code may not be aligned, as we first write documentation and then write code, so you may read documentation of code that does not yet exist!

You have been warned!

nuv, the next generation

Nuv is the nuvolaris all-mighty build tool.

This is a rewrite of the current build tools to make it super powerful.

It is basically the task tool enhanced to support:

• a bunch of embedded commands (check tools) including wsk
• the ability to download other tools
• a predefined set of tasks downloaded from github
• a way to create a hierarchy of taskfiles
• documentation for tasks powered by docopt

Note that to avoid an egg and chicken problem, nuv itself is built with his ancestor, task.

• Build it with just task build.
• Run tests with task test.

Documentation

Environment variables

The following environment variables allows to ovverride certain defaults.

• DEBUG and TRACE when set gives debugging and tracing informations, EXTRA appends extra arguments to the task invocation - useful when you need to set extra variables with a nuvopts active.
• NUV_ROOT is the folder where nuv looks for its tasks. If not defined, it follows the algorithm below to find it.
• NUV_BIN is the folder where nuv looks for binaries (external command line tools). If not defined, it defaults to the same directory where nuv is located.
• NUV_REPO is the github repo where nuv downloads its tasks. If not defined, it defaults to https://github.com/nuvolaris/olaris.
• NUV_BRANCH is the branch where nuv looks for its tasks. The branch to use is defined at build time and it is the base version (without the patch level). For example, if nuv is 0.3.0-morpheus the branch to use will be 0.3-morpheus.
• NUV_CMD is the actual command executed - defaults to the absolute path of the target of the symbolic link but it can be overriden.
• NUV_VERSION can be defined to set nuv's version value. It is useful to override version validations when updating tasks (and you know what you are doing).
• NUV_NO_NUVOPTS can be defined to disable nuvopts parsing. Useful to test hidden tasks. When this is enabled it also shows all the tasks instead of just those with a description.
• NUV_PORT is the port where nuv will run the web server. If not defined, it defaults to 9678.
• NUV_TMP is a temporary folder where you can store temp files - defaults to ~/.nuv/tmp
• NUV_APIHOST is the host for nuv -login. It is used in place of the first argument of nuv -login. If empty, the command will expect the first argument to be the apihost.
• NUV_USER: set the username for nuv -login. The default is nuvolaris. It can be overriden by passing the username as an argument to nuv -login or by setting the environment variable.
• NUV_PASSWORD: set the password for nuv -login. If not set, nuv -login will prompt for the password. It is useful for tests and non-interactive environments.
• NUV_PWD is the folder where nuv is executed (the current working directory). It is used to preserve the original working directory when nuv is used again in tasks (e.g. nuv -realpath to retrieve the correct path). Change it only if you know what you are doing!
• NUV_ROOT_PLUGIN is the folder where nuv looks for plugins. If not defined, it defaults to the same directory where nuv is located.
• NUV_OLARIS holds the head commit hash of the used olaris repo. You can see the hash with nuv -info.

Where nuv looks for binaries

• NUV_USE_COREUTILS enables the use of coreutils instead of the current unix tools implementation. They will eventually replace the current tools.

Nuv requires some binary command line tools to work with ("bins").

They are expected to be in the folder pointed by the environment variable NUV_BIN.

If this environment variable is not defined, it defaults to the same folder where nuv itself is located. The NUV_BIN folder is then added to the beginning of the PATH before executing anything else.

Nuv is normally distributed with an installer that includes all the tools for the various operating systems (linux, windows, osx).

NOTE: You can download the relevant tools when you run from source code executing task install. This task will download the command line tools and setup a link in /usr/local/bin to invoke nuv.

Where nuv looks for tasks

Nuv is an enhanced task runner. Tasks are described by task taskfiles.

Nuv is able either to run existing tasks or download them from github.

When you run nuv [<args>...] it will first look for its nuv root.

The nuv root is a folder with two files in it: nuvfile.yml (a yaml taskfile) and nuvroot.json (a json file with release information).

The first step is to locate the root folder. The algorithm to find the tools is the following.

If the environment variable NUV_ROOT is defined, it will look there first, and will check if there are the two files.

Then it will look in the current folder if there is a nuvfile.yml. If there is, it will also look for nuvroot.json. If it is not there, it will go up one level looking for a directory with nuvfile.yml and nuvtools.json, and selects it as the nuv root.

If there is not a nuvfile.yml it will look for a folder called olaris with both a nuvfile.yml and nuvtools.json in it and will select it as the nuv root.

Then it will look in ~/.nuv if there is an olaris folder with nuvfile.yml and nuvroot.json.

Finally it will look in the NUV_BIN folder if there is an olaris folder with nuvfile.yml and nuvroot.json

If everything fails, it will ask you to download some tasks with the command nuv -update. In this case it will download the latest version.

Where nuv download tasks from GitHub

Download tasks from GitHub is triggered by the nuv -update command.

The repo to use is defined by the environment variable NUV_REPO, and defaults if it is missing to https://github.com/nuvolaris/olaris

The branch to use is defined at build time. It can be overriden with the enviroment variable NUV_BRANCH.

When you run nuv -update, if there is not a ~/.nuv/olaris it will clone the current branch, otherwise it will update it.

How nuv execute tasks

It will then look to the command line parameters nuv <arg1> <arg2> <arg3> and will consider them directory names. The list can be empty.

If there is a directory name <arg1> it will change to that directory. If there is then a subdirectory <arg2> it will change to that and so on until it finds a argument that is not a directory name.

If the last argument is a directory name, will look for a nuvopts.txt. If it is there, it will show this. If it's not there, it will execute a task -t nuvfile.yml -l showing tasks with description.

If it finds an argument not corresponding to a directory, it will consider it a task to execute,

If there is not a nuvopts.txt, it will execute as a task, passing the other arguments (equivalent to task -t nuvfile.yml <arg> -- <the-other-args>).

If there is a nuvopts.txt, it will interpret it as a docopt to parse the remaining arguments as parameters. The result of parsing is a sequence of <key>=<value> that will be fed to task. So it is equivalent to invoking task -t nuvfile.yml <arg> <key>=<value> <key>=<value>...

Example

A command like nuv setup kubernetes install --context=k3s will look in the folder setup/kubernetes in the nuv root if it is there, select install as task to execute and parse the --context=k3s. It is equivalent to invoke cd setup/kubernetes ; task install -- context=k3s.

If there is a nuvopts.txt with a command <name> --flag --fl=<val> the passed parameters will be: _name_=<name> __flag=true __fl=true _val_=<val>.

Note that also this will also use the downloaded tools and the embedded commands of nuv.

Saving state

If you want to save values from a precedent execution to be provided as variables, simply write a file with a name starting and eding with _.

Nuv will read all the _*_ files assuming they are in a format <key>=<value>, will skip any line starting with # and add to the command line invoking task.

So if you have a file _server_ with:

# the server
_SERVER=myserver
# the user
_USER=myuser

at the end of task invocation there will be _SERVER=myserver _USER=myuser

Embedded tools

Currently task embeds the following tools, and you can invoke them directly prefixing them with -: (nuv -task, nuv -basename etc). Use nuv -help to list them.

• task the Task build tool
• wsk the OpenWhisk cli

Basic unix like tools (nuv -<tool> -help for details):

• basename
• cat
• cp
• dirname
• grep
• gunzip
• gzip
• head
• ls
• mv
• pwd
• rm
• sleep
• tail
• tar
• tee
• touch
• tr
• unzip
• wc
• which
• zip