Add basic support for SQLite

README.md

@@ -30,11 +30,12 @@ You are able to change the location of the model file output in the configuratio
 
   * module_name -> This is the name of the module that the models will be placed under
   * destination -> The output location for the generated models. If this is not provided then the models will go in the directory that you ran plsm in
-  * server -> this is the name of the server that you are connecting to. It can be a DNS name or an IP Address. This needs to be filled in as there are no defaults
-  * port -> The port that the database server is listening on. This needs to be provided as there may not be a default for your server
-  * database_name -> the name of the database that you are connecting to. This is required.
+  * server -> this is the name of the server that you are connecting to. It can be a DNS name or an IP Address. This needs to be filled in for PostgreSQL and MySQL as there are no defaults
+  * port -> The port that the database server is listening on. This needs to be provided except for SQLite as there may not be a default for your server
+  * database_name -> the name of the database that you are connecting to. This is required except for SQLite
   * username -> The username that is used to connect. Make sure that there is sufficient privileges to be able to connect, query tables as well as query information schemas on the database. The schema information is used to find the index/keys on each table
   * password -> This is necessary as there is no default nor is there any handling of a blank password currently.
+  * filename -> Database file full path. This is required for SQLite
   * type -> This dictates which database vendor you are using. We currently support PostgreSQL and MySQL. If no value is entered then it will default to MySQL. Accepted values: `:mysql` or `:postgres`. **Do note that this is an atom and not a string**
 
 
@@ -44,6 +45,7 @@ You are able to change the location of the model file output in the configuratio
 
   * MySQL
   * PostgreSQL
+  * SQLite
 
  We may add support to other databases based on demand. Please reach out and if you want a specific database supported. Please feel free to contribute commits that add different database vendor support!
 

lib/common/configs.ex

@@ -10,6 +10,7 @@ defmodule Plsm.Common.Configs do
       database_name: Application.get_env(:plsm, :database_name, ""),
       username: Application.get_env(:plsm, :username, ""),
       password: Application.get_env(:plsm, :password, ""),
+      filename: Application.get_env(:plsm, :filename, ""),
       type: Application.get_env(:plsm, :type, :mysql)
     }
 

lib/common/structs.ex

@@ -3,7 +3,7 @@ defmodule Plsm.Configs do
 end
 
 defmodule Plsm.Configs.Database do
-  defstruct server: "", port: "", database_name: "", username: "", password: "", type: :mysql
+  defstruct server: "", port: "", database_name: "", username: "", password: "", filename: "", type: :mysql
 end
 
 defmodule Plsm.Configs.Project do

lib/config/config.ex

@@ -38,6 +38,8 @@ defmodule Plsm.Config.Config do
     |> append_next_item()
     |> append_config_item_string("password", "password")
     |> append_next_item()
+    |> append_config_item_string("filename", "filename")
+    |> append_next_item()
     |> append_config_item_atom("type", "mysql")
   end
 
@@ -65,12 +67,13 @@ defmodule Plsm.Config.Config do
      #  Plsm configs are used to drive the extraction process. Below are what each field means:
      #    * module_name -> This is the name of the module that the models will be placed under
      #    * destination -> The output location for the generated models
-     #    * server -> this is the name of the server that you are connecting to. It can be a DNS name or an IP Address. This needs to be filled in as there are no defaults
-     #    * port -> The port that the database server is listening on. This needs to be provided as there may not be a default for your server
+     #    * server -> this is the name of the server that you are connecting to. It can be a DNS name or an IP Address. This needs to be filled in for PostgreSQL and MySQL as there are no defaults
+     #    * port -> The port that the database server is listening on. This needs to be provided for PostgreSQL and MySQL as there may not be a default for your server
      #    * database_name -> the name of the database that you are connecting to. This is required.
      #    * username -> The username that is used to connect. Make sure that there is sufficient privileges to be able to connect, query tables as well as query information schemas on the database. The schema information is used to find the index/keys on each table
-     #    * password -> This is necessary as there is no default nor is there any handling of a blank password currently.
-     #    * type -> This dictates which database vendor you are using. We currently support PostgreSQL and MySQL. If no value is entered then it will default to MySQL. Do note that this is an atom and not a string
+     #    * password -> This is necessary for PostgreSQL and MySQL as there is no default nor is there any handling of a blank password currently.
+     #    * filename -> Database file full path. This is required for SQLite
+     #    * type -> This dictates which database vendor you are using. We currently support PostgreSQL, MySQL and SQLite. If no value is entered then it will default to MySQL. Do note that this is an atom and not a string
     """
   end
 

lib/database/common.ex

@@ -13,6 +13,10 @@ defmodule Plsm.Database.Common do
         IO.puts("Using PostgreSQL...")
         Plsm.Database.create(%Plsm.Database.PostgreSQL{}, configs)
 
+      :sqlite ->
+        IO.puts("Using SQLite...")
+        Plsm.Database.create(%Plsm.Database.SQLite{}, configs)
+
       _ ->
         IO.puts("Using default database MySql...")
         Plsm.Database.create(%Plsm.Database.MySql{}, configs)

lib/database/sqlite.ex

@@ -0,0 +1,87 @@
+defmodule Plsm.Database.SQLite do
+  defstruct filename: "filename.sqlite",
+            connection: nil
+end
+
+defimpl Plsm.Database, for: Plsm.Database.SQLite do
+  @doc """
+    Create a SQLite database struct. We pass in the configs in order to
+    properly open the SQLite database
+  """
+  @spec create(Plsm.Database.SQLite, Plsm.Configs) :: Plsm.Database.SQLite
+  def create(_db, configs) do
+    %Plsm.Database.SQLite{
+      filename: configs.database.filename,
+    }
+  end
+
+  @spec connect(Plsm.Database.SQLite) :: Plsm.Database.SQLite
+  def connect(db) do
+    {_, conn} = Exqlite.Sqlite3.open(db.filename)
+
+    %Plsm.Database.SQLite{
+      connection: conn,
+      filename: db.filename,
+    }
+  end
+
+  @spec get_tables(Plsm.Database.SQLite) :: [Plsm.Database.TableHeader]
+  def get_tables(db) do
+    {_, statement} = Exqlite.Sqlite3.prepare(db.connection, "
+      SELECT
+        name
+      FROM
+        sqlite_schema
+      WHERE
+        type = 'table'
+        AND name NOT LIKE 'sqlite_%'"
+    )
+
+    {_, result} = Exqlite.Sqlite3.fetch_all(db.connection, statement)
+
+    result
+    |> List.flatten()
+    |> Enum.map(fn x -> %Plsm.Database.TableHeader{database: db, name: x} end)
+  end
+
+  @spec get_columns(Plsm.Database.SQLite, Plsm.Database.Table) :: [Plsm.Database.Column]
+  def get_columns(db, table) do
+    {_, statement} = Exqlite.Sqlite3.prepare(db.connection, "PRAGMA table_info(#{table.name})")
+    {_, result} = Exqlite.Sqlite3.fetch_all(db.connection, statement)
+
+    result
+    |> Enum.map(&to_column/1)
+  end
+
+  defp to_column(row) do
+    {_, name} = Enum.fetch(row, 1)
+    type = Enum.fetch(row, 2) |> get_type
+    {_, pk} = Enum.fetch(row, 5)
+    primary_key? = pk == 1
+    %Plsm.Database.Column{name: name, type: type, primary_key: primary_key?}
+  end
+
+  defp get_type(start_type) do
+    {_, type} = start_type
+    downcase = String.downcase(type)
+
+    cond do
+      # Determines types using the rules under paragraph 3.1 in SQLite docs:
+      # https://www.sqlite.org/datatype3.html
+      String.contains?(downcase, "int") -> :integer
+      String.contains?(downcase, "char") -> :string
+      String.contains?(downcase, "clob") -> :string
+      String.contains?(downcase, "text") -> :string
+      String.contains?(downcase, "real") -> :float
+      String.contains?(downcase, "floa") -> :float
+      String.contains?(downcase, "doub") -> :float
+
+      # Useful use cases
+      String.starts_with?(downcase, "boolean") -> :boolean
+      String.starts_with?(downcase, "text_datetime") -> :date
+      String.starts_with?(downcase, "int_datetime") -> :date
+
+      true -> :none
+    end
+  end
+end

mix.exs

@@ -15,14 +15,15 @@ defmodule Plsm.Mixfile do
   end
 
   def application do
-    [applications: [:postgrex, :myxql]]
+    [applications: [:postgrex, :myxql, :exqlite]]
   end
 
   defp deps do
     [
       {:ex_doc, "~> 0.23.0", only: :dev, runtime: false},
       {:myxql, "~> 0.4.4"},
       {:postgrex, "~> 0.15"},
+      {:exqlite, "~> 0.8.4"},
       {:ecto_sql, "~> 3.5.3", only: :test},
       {:mock, "~> 0.2.0", only: :test}
     ]

mix.lock

@@ -5,7 +5,9 @@
   "earmark_parser": {:hex, :earmark_parser, "1.4.12", "b245e875ec0a311a342320da0551da407d9d2b65d98f7a9597ae078615af3449", [:mix], [], "hexpm", "711e2cc4d64abb7d566d43f54b78f7dc129308a63bc103fbd88550d2174b3160"},
   "ecto": {:hex, :ecto, "3.5.5", "48219a991bb86daba6e38a1e64f8cea540cded58950ff38fbc8163e062281a07", [:mix], [{:decimal, "~> 1.6 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "98dd0e5e1de7f45beca6130d13116eae675db59adfa055fb79612406acf6f6f1"},
   "ecto_sql": {:hex, :ecto_sql, "3.5.3", "1964df0305538364b97cc4661a2bd2b6c89d803e66e5655e4e55ff1571943efd", [:mix], [{:db_connection, "~> 2.2", [hex: :db_connection, repo: "hexpm", optional: false]}, {:ecto, "~> 3.5.0", [hex: :ecto, repo: "hexpm", optional: false]}, {:myxql, "~> 0.3.0 or ~> 0.4.0", [hex: :myxql, repo: "hexpm", optional: true]}, {:postgrex, "~> 0.15.0", [hex: :postgrex, repo: "hexpm", optional: true]}, {:tds, "~> 2.1.1", [hex: :tds, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "d2f53592432ce17d3978feb8f43e8dc0705e288b0890caf06d449785f018061c"},
+  "elixir_make": {:hex, :elixir_make, "0.6.3", "bc07d53221216838d79e03a8019d0839786703129599e9619f4ab74c8c096eac", [:mix], [], "hexpm", "f5cbd651c5678bcaabdbb7857658ee106b12509cd976c2c2fca99688e1daf716"},
   "ex_doc": {:hex, :ex_doc, "0.23.0", "a069bc9b0bf8efe323ecde8c0d62afc13d308b1fa3d228b65bca5cf8703a529d", [:mix], [{:earmark_parser, "~> 1.4.0", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.14", [hex: :makeup_elixir, repo: "hexpm", optional: false]}], "hexpm", "f5e2c4702468b2fd11b10d39416ddadd2fcdd173ba2a0285ebd92c39827a5a16"},
+  "exqlite": {:hex, :exqlite, "0.8.4", "6cbfcd15d1307727615c8ce33589a0498e34c1020a3401bba4dd9ae723e99cc6", [:make, :mix], [{:db_connection, "~> 2.1", [hex: :db_connection, repo: "hexpm", optional: false]}, {:elixir_make, "~> 0.6", [hex: :elixir_make, repo: "hexpm", optional: false]}], "hexpm", "791fee489e0529b24218d49f39e3a9ed64fd2d26a2110a3fab3e26d8c8524b44"},
   "makeup": {:hex, :makeup, "1.0.5", "d5a830bc42c9800ce07dd97fa94669dfb93d3bf5fcf6ea7a0c67b2e0e4a7f26c", [:mix], [{:nimble_parsec, "~> 0.5 or ~> 1.0", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "cfa158c02d3f5c0c665d0af11512fed3fba0144cf1aadee0f2ce17747fba2ca9"},
   "makeup_elixir": {:hex, :makeup_elixir, "0.15.0", "98312c9f0d3730fde4049985a1105da5155bfe5c11e47bdc7406d88e01e4219b", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}, {:nimble_parsec, "~> 1.1", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "75ffa34ab1056b7e24844c90bfc62aaf6f3a37a15faa76b07bc5eba27e4a8b4a"},
   "meck": {:hex, :meck, "0.8.13", "ffedb39f99b0b99703b8601c6f17c7f76313ee12de6b646e671e3188401f7866", [:rebar3], [], "hexpm", "d34f013c156db51ad57cc556891b9720e6a1c1df5fe2e15af999c84d6cebeb1a"},

test/plsm_test.exs

@@ -24,7 +24,31 @@ defmodule PlsmTest do
     test "schema files are generated and can compile" do
       Mix.Tasks.Plsm.run([])
 
-      assert :ok == IEx.Helpers.recompile()
+      assert :ok == IEx.Helpers.recompile([force: true])
+    end
+  end
+
+  describe "plsm task using sqlite" do
+    setup do
+      Application.put_env(:plsm, :filename, File.cwd! <> "/test/support/schemas/sqlite/test.sqlite")
+      Application.put_env(:plsm, :type, :sqlite)
+      Application.put_env(:plsm, :module_name, "PlsmTest")
+      Application.put_env(:plsm, :destination, @schema_dir)
+
+      :ok
+    end
+
+    test "schema files are generated and can compile" do
+      Mix.Tasks.Plsm.run([])
+
+      assert :ok == IEx.Helpers.recompile([force: true])
+
+      assert File.exists?(@schema_dir <> "test_entity_one.ex")
+      assert File.exists?(@schema_dir <> "test_entity_two.ex")
+
+      File.ls!("#{@schema_dir}")
+      |> Enum.filter(fn file -> !String.starts_with?(file, ".") end)
+      |> Enum.each(fn file -> File.rm!(@schema_dir <> file) end)
     end
   end
 end