Add notifications feature (#72)

This adds the ability to subscribe to notifications about a table

Author: ConnorRigby

lib/sqlitex.ex

@@ -64,6 +64,24 @@ defmodule Sqlitex do
     res
   end
 
+  @doc """
+  Sets a PID to recieve notifications about table updates.
+
+  Messages will come in the shape of:
+  `{action, table, rowid}`
+
+  * `action` -> `:insert | :update | :delete`
+  * `table` -> charlist of the table name. Example: `'posts'`
+  * `rowid` -> internal immutable rowid index of the row. 
+               This is *NOT* the `id` or `primary key` of the row.
+  See the [official docs](https://www.sqlite.org/c3ref/update_hook.html).
+  """
+  @spec set_update_hook(connection, pid, Keyword.t()) :: :ok | {:error, term()}
+  def set_update_hook(db, pid, opts \\ []) do
+    timeout = Keyword.get(opts, :db_timeout, Config.db_timeout())
+    :esqlite3.set_update_hook(pid, db, timeout)
+  end
+
   @spec exec(connection, string_or_charlist) :: :ok | sqlite_error
   @spec exec(connection, string_or_charlist, Keyword.t) :: :ok | sqlite_error
   def exec(db, sql, opts \\ []) do

lib/sqlitex/server.ex

@@ -109,6 +109,11 @@ defmodule Sqlitex.Server do
     {:reply, result, {db, stmt_cache, timeout}}
   end
 
+  def handle_call({:set_update_hook, pid, opts}, _from, {db, stmt_cache, timeout}) do
+    result = Sqlitex.set_update_hook(db, pid, opts)
+    {:reply, result, {db, stmt_cache, timeout}}
+  end
+
   def handle_cast(:stop, {db, stmt_cache, timeout}) do
     {:stop, :normal, {db, stmt_cache, timeout}}
   end
@@ -132,6 +137,10 @@ defmodule Sqlitex.Server do
     GenServer.call(pid, {:query_rows, sql, opts}, timeout(opts))
   end
 
+  def set_update_hook(server_pid, notification_pid, opts \\ []) do
+    GenServer.call(server_pid, {:set_update_hook, notification_pid, opts}, timeout(opts))
+  end
+
   @doc """
   Prepares a SQL statement for future use.
 

mix.exs

@@ -4,21 +4,23 @@ defmodule Sqlitex.Mixfile do
   def project do
     [
       app: :sqlitex,
-      version: "1.4.3",
+      version: "1.5.0",
       elixir: "~> 1.4",
       deps: deps(),
       package: package(),
+      source_url: "https://github.com/Sqlite-Ecto/sqlitex",
       test_coverage: [tool: ExCoveralls],
       preferred_cli_env: [
-         coveralls: :test,
-         "coveralls.circle": :test,
-         "coveralls.detail": :test,
-         "coveralls.post": :test,
-         "coveralls.html": :test],
+        coveralls: :test,
+        "coveralls.circle": :test,
+        "coveralls.detail": :test,
+        "coveralls.post": :test,
+        "coveralls.html": :test
+      ],
       description: """
         A thin Elixir wrapper around esqlite
       """,
-      dialyzer: [plt_add_deps: :transitive],
+      dialyzer: [plt_add_deps: :transitive]
     ]
   end
 
@@ -30,22 +32,24 @@ defmodule Sqlitex.Mixfile do
   # Type `mix help deps` for more examples and options
   defp deps do
     [
-      {:esqlite, "~> 0.2.4"},
+      {:esqlite, "~> 0.2.5"},
       {:decimal, "~> 1.5"},
       {:credo, "~> 0.10", only: :dev},
       {:dialyxir, "~> 1.0.0-rc.3", only: :dev, runtime: false},
       {:excoveralls, "~> 0.10", only: :test},
       {:ex_doc, "~> 0.19", only: :docs, runtime: false},
       {:excheck, "~> 0.6", only: :test},
-      {:triq, "~> 1.2", only: :test},
+      {:triq, "~> 1.2", only: :test}
     ]
   end
 
   defp package do
-   [maintainers: ["Michael Ries", "Jason M Barnes", "Graeme Coupar", "Eric Scouten", "Connor Rigby"],
-     licenses: ["MIT"],
-     links: %{
-      github: "https://github.com/Sqlite-Ecto/sqlitex",
-      docs: "http://hexdocs.pm/sqlitex"}]
+    [
+      licenses: ["MIT"],
+      links: %{
+        "GitHub" => "https://github.com/Sqlite-Ecto/sqlitex",
+        "docs" => "http://hexdocs.pm/sqlitex"
+      }
+    ]
   end
 end

mix.lock

@@ -5,7 +5,7 @@
   "decimal": {:hex, :decimal, "1.5.0", "b0433a36d0e2430e3d50291b1c65f53c37d56f83665b43d79963684865beab68", [:mix], [], "hexpm"},
   "dialyxir": {:hex, :dialyxir, "1.0.0-rc.3", "774306f84973fc3f1e2e8743eeaa5f5d29b117f3916e5de74c075c02f1b8ef55", [:mix], [], "hexpm"},
   "earmark": {:hex, :earmark, "1.2.6", "b6da42b3831458d3ecc57314dff3051b080b9b2be88c2e5aa41cd642a5b044ed", [:mix], [], "hexpm"},
-  "esqlite": {:hex, :esqlite, "0.2.4", "3a8a352c190afe2d6b828b252a6fbff65b5cc1124647f38b15bdab3bf6fd4b3e", [:rebar3], [], "hexpm"},
+  "esqlite": {:hex, :esqlite, "0.2.5", "cab6d87aeb5f33d848b9bb8a21129e9512ea608f930d4c63576942d8f7d72218", [:rebar3], [], "hexpm"},
   "ex_doc": {:hex, :ex_doc, "0.19.1", "519bb9c19526ca51d326c060cb1778d4a9056b190086a8c6c115828eaccea6cf", [:mix], [{:earmark, "~> 1.1", [hex: :earmark, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.7", [hex: :makeup_elixir, repo: "hexpm", optional: false]}], "hexpm"},
   "excheck": {:hex, :excheck, "0.6.0", "f8595a8ac2c0abc0d060c1a4fce7d26f41574543366a52d5f3c84de30a69747b", [:mix], [], "hexpm"},
   "excoveralls": {:hex, :excoveralls, "0.10.0", "a4508bdd408829f38e7b2519f234b7fd5c83846099cda348efcb5291b081200c", [:mix], [{:hackney, "~> 1.13", [hex: :hackney, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm"},

test/sqlitex_test.exs

@@ -12,6 +12,19 @@ defmodule SqlitexTest do
     {:ok, golf_db: TestDatabase.init(db)}
   end
 
+  test "set_update_hook", %{golf_db: db} do
+    :ok = Sqlitex.set_update_hook(db, self())
+    :ok = Sqlitex.exec(db, "CREATE TABLE test (id INTEGER PRIMARY KEY, val STRING);")
+    :ok = Sqlitex.exec(db, "INSERT INTO test (val) VALUES ('this is a test');")
+    assert_receive {:insert, 'test', 1}
+
+    {:ok, conn} = Sqlitex.Server.start_link(@shared_cache)
+    :ok = Sqlitex.Server.set_update_hook(conn, self())
+    :ok = Sqlitex.Server.exec(conn, "CREATE TABLE blerps (id INTEGER PRIMARY KEY, val STRING);")
+    :ok = Sqlitex.Server.exec(conn, "INSERT INTO blerps (val) VALUES ('this is a test');")
+    assert_receive {:insert, 'blerps', 1}
+  end
+
   test "server basic query" do
     {:ok, conn} = Sqlitex.Server.start_link(@shared_cache)
     {:ok, [row]} = Sqlitex.Server.query(conn, "SELECT * FROM players ORDER BY id LIMIT 1")