UAInspector v2.1.0 UAInspector.Config View Source

Module to simplify access to configuration values with default values.

There should be no configuration required to start using :ua_inspector if you rely on the default values:

remote_database = "https://raw.githubusercontent.com/matomo-org/device-detector/master/regexes"
remote_shortcode = "https://raw.githubusercontent.com/matomo-org/device-detector/master"

config :ua_inspector,
  database_path: Application.app_dir(:ua_inspector, "priv"),
  http_opts: [],
  remote_path: [
    bot: remote_database,
    browser_engine: remote_database <> "/client",
    client: remote_database <> "/client",
    device: remote_database <> "/device",
    os: remote_database,
    short_code_map: remote_shortcode,
    vendor_fragment: remote_database
  ],
  remote_release: "master",
  startup_silent: false,
  startup_sync: true,
  yaml_file_reader: {:yamerl_constr, :file, [[:str_node_as_binary]]}

The default :database_path is evaluated at runtime and not compiled into a release!

How to Configure

There are two ways to change the configuration values with the preferred way depending on your environment and personal taste.

Static Configuration

If you can ensure the configuration are static and not dependent on i.e. the server your application is running on, you can use a static approach by modifying your config.exs file:

config :ua_inspector,
  database_path: "/path/to/ua_inspector/databases"

Dynamic Configuration

If a compile time configuration is not possible or does not match the usual approach taken in your application you can use a runtime approach.

This is done by defining an initializer module that will automatically be called by UAInspector.Supervisor upon startup/restart. The configuration is expected to consist of a {mod, fun} or {mod, fun, args} tuple:

# {mod, fun}
config :ua_inspector,
  init: {MyInitModule, :my_init_mf}

# {mod, fun, args}
config :ua_inspector,
  init: {MyInitModule, :my_init_mfargs, [:foo, :bar]}

defmodule MyInitModule do
  @spec my_init_mf() :: :ok
  def my_init_mf(), do: my_init_mfargs(:foo, :bar)

  @spec my_init_mfargs(atom, atom) :: :ok
  def my_init_mfargs(:foo, :bar) do
    priv_dir = Application.app_dir(:my_app, "priv")

    Application.put_env(:ua_inspector, :database_path, priv_dir)
  end
end

The function is required to always return :ok.

Startup Behaviour

You can change this behaviour to have the application force an asynchronous database loading during the initial startup:

config :ua_inspector,
  startup_sync: false

This can lead to the first parsing calls to work with an empty database and therefore not return the results you expect.

Starting Silently

When starting the application you will receive warnings if the database is not available. If you want to hide these messages you can configure the startup the be completely silent:

config :ua_inspector,
  startup_silent: true

Database Configuration

Configuring the database to use can be done using two related values:

  • :database_path
  • :remote_path

The :database_path is the directory to look for when loading the databases. It is also the place where UAInspector.Downloader stores a downloaded copy.

For the time being the detailed list of database files is not configurable. This is a major caveat for personal database copies and short code mappings (they have additional path information appended to the base). This behaviour is subject to change.

The full configuration for remote paths contains the following values:

config :ua_inspector
  remote_path: [
    bot: "http://example.com",
    browser_engine: "http://example.com",
    client: "http://example.com",
    device: "http://example.com",
    os: "http://example.com",
    short_code_map: "http://example.com",
    vendor_fragment: "http://example.com"
  ]

Default Database Release Version

If you are using the default database the newest version from the "master" branch will be used. You can also configure a different release to be used:

config :ua_inspector,
  remote_release: "v1.0.0"

Download Configuration

Using the default configuration all download requests for your database files are done using :hackney. To pass custom configuration values to hackney you can use the key :http_opts:

config :ua_inspector,
  http_opts: [proxy: "http://mycompanyproxy.com"]

Please see :hackney.request/5 for a complete list of available options.

If you want to change the library used to download the databases you can configure a module implementing the UAInspector.Downloader.Adapter behaviour:

config :ua_inspector,
  downloader_adapter: MyDownloaderAdapter

YAML File Reader Configuration

By default the library :yamerl will be used to read and decode the yaml database files. You can configure this reader to be a custom module:

config :ua_inspector,
  yaml_file_reader: {module, function}

config :ua_inspector,
  yaml_file_reader: {module, function, extra_args}

The configured module will receive the file to read as the first argument with any optionally configured extra arguments after that.

Link to this section Summary

Functions

Returns the configured database path.

Returns the remote url of a database file.

Returns whether the remote database (at least one type) matches the default.

Returns the configured downloader adapter module.

Provides access to configuration values with optional environment lookup.

Calls the optionally configured init method.

Returns the {mod, fun, extra_args} to be used when reading a yaml file.

Link to this section Functions

Specs

database_path() :: String.t()

Returns the configured database path.

If the path is not defined the priv dir of :ua_inspector as returned by Application.app_dir(:ua_inspector, "priv") will be used.

Link to this function

database_url(type, file)

View Source

Specs

database_url(atom(), String.t()) :: String.t()

Returns the remote url of a database file.

Link to this function

default_remote_database?()

View Source

Specs

default_remote_database?() :: boolean()

Returns whether the remote database (at least one type) matches the default.

Specs

downloader_adapter() :: module()

Returns the configured downloader adapter module.

The modules is expected to adhere to the behaviour defined in UAInspector.Downloader.Adapter.

Link to this function

get(key, default \\ nil)

View Source

Specs

get(atom() | [atom()], term()) :: term()

Provides access to configuration values with optional environment lookup.

Specs

init_env() :: :ok

Calls the optionally configured init method.

Specs

yaml_file_reader() :: {module(), atom(), [term()]}

Returns the {mod, fun, extra_args} to be used when reading a yaml file.