Features

Boleto (Bank Slip)

• [x] Validate boleto linha digitável (typeable line) and barcode
• [x] Parse boleto data into structured format
• [x] Banking Boletos - Bank collection boletos
  • Linha digitável: 47 digits
  • Barcode: 44 digits
• [x] Convenio Boletos - Utility/tax boletos (starting with "8")
  • Linha digitável: 48 digits
  • Barcode: 44 digits

State Registration (Inscrição Estadual - IE)

• [x] Validate IE numbers with auto-detection
• [x] Parse IE into structured data with state-specific formatting
• [x] All 27 states supported: AC, AL, AM, AP, BA, CE, DF, ES, GO, MA, MG, MS, MT, PA, PB, PE, PI, PR, RJ, RN, RO, RR, RS, SC, SE, SP, TO
• [x] Multiple state detection - Returns all states that match when algorithms overlap

General

• [x] Full typespec coverage
• [x] Comprehensive test suite

Roadmap

Upcoming features for future releases:

• [ ] CPF - Validate, format, and generate CPF numbers
• [ ] CNPJ - Validate, format, and generate CNPJ numbers
• [ ] CEP - Validate and format postal codes
• [ ] Phone - Validate and format Brazilian phone numbers
• [ ] PIS/PASEP - Validate social security numbers
• [ ] Vehicle Plate - Validate traditional and Mercosul formats
• [ ] CNH - Validate driver's license numbers
• [ ] RENAVAM - Validate vehicle registration numbers
• [ ] Currency - Format BRL currency values

Installation

Add brasilex to your list of dependencies in mix.exs:

def deps do
  [
    {:brasilex, "~> 0.3.0"}
  ]
end

Then run:

$ mix deps.get

Usage

Validate a Boleto

# Returns :ok or {:error, reason}
Brasilex.validate_boleto("00190.00009 01234.567890 12345.678908 1 00000000000000")
#=> :ok

Brasilex.validate_boleto("invalid")
#=> {:error, :invalid_length}

# Bang version raises on error
Brasilex.validate_boleto!("00190.00009 01234.567890 12345.678908 1 00000000000000")
#=> :ok

Brasilex.validate_boleto!("invalid")
#=> ** (Brasilex.ValidationError) Invalid length: wrong number of digits

Parse a Boleto

{:ok, boleto} = Brasilex.parse_boleto("00190000090123456789012345678908100000000000000")

boleto.type        #=> :banking
boleto.bank_code   #=> "001"
boleto.amount      #=> Decimal.new("150.00") or nil
boleto.due_date    #=> ~D[2020-07-04] or nil
boleto.barcode     #=> "00191000000000000001234567890123456789080"

# Bang version raises on error
boleto = Brasilex.parse_boleto!("00190000090123456789012345678908100000000000000")

Input Formats

The library accepts both linha digitável and barcode, with or without formatting:

# Linha digitável with dots, spaces, hyphens
Brasilex.validate_boleto("00190.00009 01234.567890 12345.678908 1 00000000000000")

# Linha digitável digits only (47 or 48 digits)
Brasilex.validate_boleto("00190000090123456789012345678908100000000000000")

# Barcode (44 digits)
Brasilex.validate_boleto("23791843400000199003812860000000003000000004")

Boleto Types

Banking Boleto (47 digits)

Bank collection boletos used for payments, invoices, etc.

{:ok, boleto} = Brasilex.parse_boleto("23793.38128 60000.000003 00000.000400 1 84340000019900")

boleto.type          #=> :banking
boleto.bank_code     #=> "237" (e.g., "001" = Banco do Brasil)
boleto.currency_code #=> "9" (BRL)
boleto.amount        #=> Decimal.new("199.00") or nil if any amount
boleto.due_date      #=> ~D[2020-07-04] or nil if no due date
boleto.free_field    #=> "3812860000000003000000004" (25 digits of bank-defined content)

Convenio Boleto (48 digits)

Utility bills, taxes, and government collections. First digit is always "8".

{:ok, boleto} = Brasilex.parse_boleto("846700000005 573200481018 150820204176 494672890166")

boleto.type       #=> :convenio
boleto.segment    #=> "6" (determines validation algorithm)
boleto.amount     #=> Decimal.new("573.20") or nil
boleto.company_id #=> "0481018150820204176494672890166"
boleto.free_field #=> Segment-specific content

State Registration (IE)

Validate an IE

# Returns :ok or {:error, reason}
Brasilex.validate_ie("110.042.490.114")
#=> :ok

Brasilex.validate_ie("12345")
#=> {:error, :invalid_length}

# Bang version raises on error
Brasilex.validate_ie!("110.042.490.114")
#=> :ok

Parse an IE

# Returns all states that match the IE
{:ok, [ie]} = Brasilex.parse_ie("110.042.490.114")

ie.state      #=> :sp
ie.raw        #=> "110042490114"
ie.formatted  #=> "110.042.490.114"

# Some IEs are valid for multiple states (shared algorithms)
{:ok, ies} = Brasilex.parse_ie("820000000")
Enum.map(ies, & &1.state)
#=> [:am, :sc, :se]

# Each IE has state-specific formatting
am_ie = Enum.find(ies, & &1.state == :am)
am_ie.formatted  #=> "82.000.000-0"

sc_ie = Enum.find(ies, & &1.state == :sc)
sc_ie.formatted  #=> "820.000.000"

Supported States

All 27 Brazilian states are supported with their specific validation rules:

Error Handling

All functions return {:ok, result} or {:error, reason} tuples:

case Brasilex.validate_boleto(input) do
  :ok ->
    IO.puts("Valid boleto!")

  {:error, :invalid_length} ->
    IO.puts("Wrong number of digits (expected 47 or 48)")

  {:error, :invalid_format} ->
    IO.puts("Invalid characters found")

  {:error, :invalid_checksum} ->
    IO.puts("General check digit validation failed")

  {:error, {:invalid_field_checksum, n}} ->
    IO.puts("Field #{n} check digit validation failed")

  {:error, :unknown_type} ->
    IO.puts("Could not determine boleto type")
end

Bang Variants

Bang variants raise Brasilex.ValidationError for cleaner pipelines:

try do
  boleto = Brasilex.parse_boleto!("invalid")
  # Process boleto...
rescue
  e in Brasilex.ValidationError ->
    IO.puts("Validation failed: #{e.message}")
end

Response Types with Structs

For better type safety and developer experience, Brasilex provides struct definitions:

# Boleto struct with all parsed fields
{:ok, %Brasilex.Boleto{} = boleto} = Brasilex.parse_boleto("...")

# Banking boleto fields
boleto.type          #=> :banking
boleto.bank_code     #=> String.t()
boleto.currency_code #=> String.t()
boleto.amount        #=> Decimal.t() | nil
boleto.due_date      #=> Date.t() | nil
boleto.free_field    #=> String.t()
boleto.barcode       #=> String.t()

# Convenio boleto fields
boleto.type       #=> :convenio
boleto.segment    #=> String.t()
boleto.amount     #=> Decimal.t() | nil
boleto.company_id #=> String.t()
boleto.free_field #=> String.t()
boleto.barcode    #=> String.t()

# IE struct with parsed fields
{:ok, [%Brasilex.IE{} = ie]} = Brasilex.parse_ie("110.042.490.114")

ie.state      #=> :sp
ie.raw        #=> "110042490114"
ie.formatted  #=> "110.042.490.114"

Available Structs

Validation Details

Check Digit Algorithms

Brasilex validates boletos using the standard Brazilian algorithms:

• Banking boletos (47 digits): Module 10 for field check digits, Module 11 for general verifier
• Convenio boletos (48 digits): Module 10 or Module 11 depending on segment identifier

What Gets Validated

1. Length: Must be exactly 44, 47, or 48 digits (after removing formatting)
2. Format: Must contain only digits (after removing dots, spaces, hyphens)
3. Check digits: All field-level and general check digits are verified
4. Type detection: Boleto type is determined from digit count and first character
   • 44 digits starting with "8" → Convenio barcode
   • 44 digits (other) → Banking barcode
   • 47 digits → Banking linha digitável
   • 48 digits starting with "8" → Convenio linha digitável

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/stlucasgarcia/brasilex.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/my-feature)
3. Commit your changes (git commit -am 'Add my feature')
4. Push to the branch (git push origin feature/my-feature)
5. Create a Pull Request

License

The library is available as open source under the terms of the MIT License.