# Flamel
[](https://github.com/themusicman/flamel/actions/workflows/elixir.yml)
This package is a bag of helper functions. Some might be questionable but they are what they are so use them as you will.
## Installation
If [available in Hex](https://hex.pm/packages/flamel), the package can be installed
by adding `flamel` to your list of dependencies in `mix.exs`:
```elixir
def deps do
[
{:flamel, "~> 1.0.0"}
]
end
```
or mainline the latest:
```elixir
def deps do
[
{:flamel, github: "themusicman/flamel", branch: "main"}
]
end
```
## Examples
### Context
Here is a trivial example:
```elixir
alias Flamel.Context
context =
Context.new()
|> assign_user(user)
|> authorize()
|> perform_action()
if context.assigns[:action_performed?] do
# something you are allowed to do
end
def assign_user?(%Context{} = context, user) do
Context.assign(context, :user, user)
end
def authorize(%Context{assigns: %{user: %{type: :admin}} = context) do
context
end
def authorize(%Context{} = context) do
Context.halt!(context, "Not permitted")
end
def perform_action(%Context{halt: true}) do
# do nothing
context
end
def perform_action(%Context{assigns: %{user: user}} = context) do
# Do something
Context.assign(context, %{action_performed_by: user, action_performed?: true})
end
```
### Utility
```elixir
Flamel.try_and_return(fn -> :ok end) == :ok
Flamel.try_and_return(fn -> raise "error" end, {:ok, :default_value}) == {:ok, :default_value}
Flamel.unwrap_ok!({:ok, []}) == []
Flamel.unwrap_ok_or_nil({:error, "boom!"}) == nil
```
### Predicates
```elixir
Flamel.blank?(%{}) == true
# present is the opposite of blank?
Flamel.present?(%{}) == false
```
### Conversions
```elixir
Flamel.to_boolean("Y") == true
Flamel.to_integer(nil) == ""
Flamel.to_integer(1) == 1
Flamel.to_float(nil) == 0.0
Flamel.to_float(1) == 1.0
Flamel.to_string(nil) == ""
```
### DateTime
```elixir
Flamel.Moment.to_datetime("2000-10-31T01:30:00.000-05:00") == ~U[2000-10-31 06:30:00.000Z]
Flamel.Moment.to_datetime(~N[2019-10-31 23:00:07]) == ~N[2019-10-31 23:00:07]
Flamel.Moment.to_date(~D[2000-10-31]) == ~D[2000-10-31]
Flamel.Moment.to_date("2000-10-31") == ~D[2000-10-31]
Flamel.Moment.to_iso8601(~U[2000-10-31 06:30:00.000Z]) == "2000-10-31T06:30:00.000Z"
Flamel.Moment.to_iso8601(~D[2019-10-31]) == "2019-10-31"
```
### Maps/Structs
```elixir
Flamel.Map.atomize_keys(%{"first_name" => "Thomas", "dob" => "07/01/1981"}) == %{first_name: "Thomas", dob: "07/01/1981"}
Flamel.Map.Indifferent.get(%{test: "value"}, "test") == "value"
Flamel.Map.Indifferent.get(%{test: "value"}, :test) == "value"
Flamel.Map.Safely.get(%Person{name: "Todd"}, &String.upcase(&1.name)) == "TODD"
Flamel.Map.Safely.get(%{name: "Todd"}, &String.upcase(&1.bad_field), "N/A") == "N/A"
```
All of the to_* functions are implemented using [Protocols](https://hexdocs.pm/elixir/1.16/protocols.html). So you can implement you own behavior for types that do not already have implementations.
Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
be found at <https://hexdocs.pm/flamel>.