BrewDG

Homebrew Dependency Graphs.

BrewDG allows you to visualize your homebrew package dependencies. It can also take a list of packages, and give you those packages, with each package preceeded by its dependencies (and its dependencies will be preceeded by its dependencies, and so forth - see the Example).

Installation

gem install brew_dg

N.B.: this is not the sort of tool that should be distributed as a gem. See Gary Bernhardt's comment on this in the selecta README. Alas, while brew_dg has a couple of bulky dependencies, it'll remain a gem.

Examples

brew_dg is pretty slow since it's issuing and parsing the output of brew commands. Which is to say, you may want to have a beverage to sip while using it, particularly on a large number of packages.

Listing Stuff

List packages plus their recommended dependencies. This is what compelled me to write brew_dg.
```
$ brew_dg git postgresql sqlite redis
> git readline ossp-uuid postgresql sqlite redis
```
We've added two packages to the initial list: ossp-uuid, which is recommended for postgresql, and readline, which is recommended for sqlite. Note that readline is in fact required for postgresql; perhaps in the future we will take that into ordering consideration.
List all of a package's dependencies, including Optional and Build dependencies.

   $ brew_dg -a postgis
   > readline ossp-uuid postgresql proj geos json-c libpng jpeg giflib libtiff \
       lzlib libgeotiff sqlite freexl libxml2 pkg-config libspatialite cmake \
       mysql gdal autoconf automake libtool gpp postgis

Visualizing Stuff

N.B.: brew_dg uses ruby-graphviz to draw graphs, so you'll need to install graphviz first.

Visualize homebrew dependencies. See Graph for visual details. (Note that these visualizations require graphviz):
```
$ brew_dg -o library.png
$ open library.png
```
Visualize a package's recommended and required dependencies (as well as their dependencies)
```
$ brew_dg -o postgis.png postgis
$ open postgis.png
```
Visualize all of a package's dependencies, including Optional and Build dependencies

  $ brew_dg -a -o postgis.png postgis
  $ open postgis.png

Man Page-ish

Synopsis

brew_dg [options] [package package ...]

Description

Assuming for the moment that brew_dg is given no options, for each package given, brew_dg will display that package, along with its Required and Recommended dependencies. brew_dg orders the packages such that a given package will not be installed until its Recommended and Required dependencies have been installed.

If no options or pacakges are given, brew_dg displays any homebrew packages you've installed, along with any uninstalled, Recommended dependencies in an order such that a package will not be installed until its dependencies have been installed.

The following options allow users to configure and tweak the details of the preceeding description:

-a
    Display all dependencies, including Optional and Build dependencies.

-o [file]
    Draw graph, and write it to file. Directed edges are read as "depends
    on." If given a directory $DIR, the file will be located at
    $DIR/library.png. See Graph section for stylistic details.

-O [file]
    Draw inverted graph, and write it to file. Directed edges are read as
    "is a dependency of." If given a directory $DIR, the file will be
    located at $DIR/library.png. See [Graph](#graph) section for stylistic
    details.

-t types
    Display only dependencies of the comma-delimited types specified. e.g.
    `-t Recommended,Optional'

Graph

The graph uses edge and arrow styles to differentiate between dependency types.

Required:    A solid edge with a filled, triangular arrow.
Recommended: A solid edge with an empty, triangular arrow.
Optional:    A dotted edge with a filled, triangular arrow.
Build:       A dotted edge with a tee-shaped arrow.