ExPyshp

Read and write shapefiles using pyshp from Elixir with pythonx.

Installation

If available in Hex, the package can be installed by adding ex_pyshp to your list of dependencies in mix.exs:

def deps do
  [
    {:ex_pyshp, "~> 0.1.0"}
  ]
end

Usage

Reading

# Extract from the ZIP file and get list of files
extraction_result = ExPyshp.extract("shp.zip")

# Process the extraction result and read each shapefile group
shapefile_results =
  case extraction_result do
    {:ok, shapefile_pairs} ->
      # For each shapefile group, call read and capture the result in a list
      Enum.map(shapefile_pairs, fn %{shp: shp_path, dbf: dbf_path, shx: shx_path} ->
        case ExPyshp.read(shp_path, dbf_path, shx_path) do
          {:ok, base_name, data} -> {:ok, base_name, data}
          {:error, base_name, reason} -> {:error, base_name, reason}
        end
      end)

    {:error, reason} ->
      IO.puts("Error extracting shapefiles: #{reason}")
      []
  end

# Process and inspect each result:
Enum.each(shapefile_results, fn
  {:ok, base_name, shapefile_data} ->
    IO.inspect(shapefile_data, label: "Shapefile data from #{base_name}")
  {:error, base_name, reason} ->
    IO.puts("Error reading shapefile for #{base_name}: #{reason}")
end)

Writing

data = [
  %{
    "record" => %{"name" => "Feature1", "value" => 123},
    "geometry" => %Geo.Point{coordinates: {1.0, 2.0}}
  },
  %{
    "record" => %{"name" => "Feature2", "value" => 456},
    "geometry" => %Geo.Point{coordinates: {3.0, 4.0}}
  }
]

ExPyshp.write("output_path", "name", data)

Add shapefiles to zip archive

file_paths = [
  "/path/to/file1.shp",
  "/path/to/file1.dbf",
  "/path/to/file1.shx"
]

case ExPyshp.archive("/output/directory", "shapefile_archive", file_paths) do
  {:ok, zip_path} ->
    IO.puts("ZIP archive created at: #{zip_path}")

  {:error, reason} ->
    IO.puts("Failed to create ZIP archive: #{reason}")
end