From 23029f9324e473d927a56c6860ae2dc0faf1a894 Mon Sep 17 00:00:00 2001
From: pmeinhardt <mnhrdt@gmail.com>
Date: Wed, 3 Feb 2021 22:11:44 +0100
Subject: [PATCH] Iterate on tarpipe upload implementation

---
 examples/tarpipe.exs | 109 +++++++++++++++++++++++++++----------------
 1 file changed, 70 insertions(+), 39 deletions(-)

diff --git a/examples/tarpipe.exs b/examples/tarpipe.exs
index 30cd978..01c6d30 100644
--- a/examples/tarpipe.exs
+++ b/examples/tarpipe.exs
@@ -3,59 +3,90 @@
 ctx =
   SSHKit.Context.new()
   |> SSHKit.Context.path("/tmp")
-  |> SSHKit.Context.user("other")
-  |> SSHKit.Context.group("other")
+  # |> SSHKit.Context.user("other")
+  # |> SSHKit.Context.group("other")
   |> SSHKit.Context.umask("0077")
 
-defmodule Xfer do
-  # https://github.com/erlang/otp/blob/OTP-23.2.1/lib/ssh/src/ssh.hrl
-  def to_binary(data) when is_list(data) do
-    :erlang.iolist_to_binary(data)
-  catch
-    _ -> :unicode.characters_to_binary(data)
-  end
+defmodule TP do
+  def upload!(conn, source, dest, opts \\ []) do
+    ctx = Keyword.get(opts, :context, SSHKit.Context.new())
 
-  def to_binary(data) when is_binary(data) do
-    data
-  end
-end
+    Stream.resource(
+      fn ->
+        {:ok, chan} = SSHKit.Channel.open(conn, [])
+        command = SSHKit.Context.build(ctx, "tar -x")
+        :success = SSHKit.Channel.exec(chan, command)
 
-source = "test/fixtures"
+        owner = self()
 
-:ok =
-  with {:ok, chan} <- SSHKit.Channel.open(conn, []) do
-    command = SSHKit.Context.build(ctx, "tar -x")
+        tarpipe = spawn(fn ->
+          {:ok, tar} = :erl_tar.init(chan, :write, fn
+            :position, {^chan, position} ->
+              # IO.inspect(position, label: "position")
+              {:ok, 0}
 
-    case SSHKit.Channel.exec(chan, command) do
-      :success ->
-        # In case of failed upload, check command output:
-        # IO.inspect(SSHKit.Channel.recv(chan))
+            :write, {^chan, data} ->
+              # TODO: Send data in chunks based on channel window size?
+              # IO.inspect(data, label: "write")
+              # In case of failing upload, check command output:
+              # IO.inspect(SSHKit.Channel.recv(chan, 0))
+              chunk = to_binary(data)
 
-        {:ok, tar} = :erl_tar.init(chan, :write, fn
-          :position, {^chan, position} ->
-            # IO.write("tar position: #{inspect(position)}")
-            {:ok, 0}
+              receive do
+                :cont ->
+                  :ok = SSHKit.Channel.send(chan, chunk)
+              end
+              send(owner, {:write, chan, self(), chunk})
+              :ok
 
-          :write, {^chan, data} ->
-            # TODO: Send data in chunks based on channel window size?
-            :ok = SSHKit.Channel.send(chan, Xfer.to_binary(data))
-            :ok
+            :close, ^chan ->
+              # IO.puts("close")
+              :ok = SSHKit.Channel.eof(chan)
+              send(owner, {:close, chan, self()})
+              :ok
+          end)
 
-          :close, ^chan ->
-            :ok = SSHKit.Channel.eof(chan)
-            :ok
+          :ok = :erl_tar.add(tar, to_charlist(source), to_charlist(Path.basename(source)), [])
+          :ok = :erl_tar.close(tar)
         end)
 
-        :ok = :erl_tar.add(tar, to_charlist(source), to_charlist(Path.basename(source)), [])
+        {chan, tarpipe}
+      end,
+      fn {chan, tarpipe} ->
+        send(tarpipe, :cont)
 
-        :ok = :erl_tar.close(tar)
+        receive do
+          {:write, ^chan, ^tarpipe, data} ->
+            {[{:write, chan, data}], {chan, tarpipe}}
 
-      :failure ->
-        {:error, :failure}
+          {:close, ^chan, ^tarpipe} ->
+            {:halt, {chan, tarpipe}}
+        end
+      end,
+      fn {chan, tarpipe} ->
+        :ok = SSHKit.Channel.close(chan)
+        :ok = SSHKit.Channel.flush(chan)
+      end
+    )
+  end
 
-      other ->
-        other
-    end
+  # https://github.com/erlang/otp/blob/OTP-23.2.1/lib/ssh/src/ssh.hrl
+  def to_binary(data) when is_list(data) do
+    :erlang.iolist_to_binary(data)
+  catch
+    _ -> :unicode.characters_to_binary(data)
   end
 
+  def to_binary(data) when is_binary(data) do
+    data
+  end
+end
+
+stream = TP.upload!(conn, "test/fixtures", "upload", context: ctx)
+
+Enum.each(stream, fn
+  {:write, chan, data} ->
+    IO.puts("Upload, sent #{byte_size(data)} bytes")
+end)
+
 :ok = SSHKit.close(conn)