chore: Allow to change cwd of transcoder ffmpeg

lib/ffmpeg.rb

@@ -113,10 +113,12 @@ def ffmpeg_binary
     # Safely captures the standard output and the standard error of the ffmpeg command.
     #
     # @param args [Array<String>] The arguments to pass to ffmpeg.
+    # @param spawn [Hash] Options hash forwarded to Process.spawn
     # @return [Array<String, Process::Status>] The standard output, the standard error, and the process status.
-    def ffmpeg_capture3(*args)
+    def ffmpeg_capture3(*args, spawn: nil)
       logger.debug(self) { "ffmpeg -y #{Shellwords.join(args)}" }
-      FFMPEG::IO.capture3(ffmpeg_binary, '-y', *args)
+      spawn ||= {}
+      FFMPEG::IO.capture3(ffmpeg_binary, '-y', *args, **spawn)
     end
 
     # Starts a new ffmpeg process with the given arguments.
@@ -125,29 +127,33 @@ def ffmpeg_capture3(*args)
     # to the specified block.
     #
     # @param args [Array<String>] The arguments to pass to ffmpeg.
+    # @param spawn [Hash] Options hash forwarded to Process.spawn
     # @yieldparam stdin (+IO+) The standard input stream.
     # @yieldparam stdout (+FFMPEG::IO+) The standard output stream.
     # @yieldparam stderr (+FFMPEG::IO+) The standard error stream.
     # @yieldparam wait_thr (+Thread+) The child process thread.
     # @return [Process::Status, Array<IO, Thread>]
-    def ffmpeg_popen3(*args, &)
+    def ffmpeg_popen3(*args, spawn: nil, &)
       logger.debug(self) { "ffmpeg -y #{Shellwords.join(args)}" }
-      FFMPEG::IO.popen3(ffmpeg_binary, '-y', *args, &)
+      spawn ||= {}
+      FFMPEG::IO.popen3(ffmpeg_binary, '-y', *args, **spawn, &)
     end
 
     # Execute a ffmpeg command.
     #
     # @param args [Array<String>] The arguments to pass to ffmpeg.
     # @param reporters [Array<Class<FFMPEG::Reporters::Output>>] The reporters to use to parse the output.
+    # @param spawn [Hash] Options hash forwarded to Process.spawn
     # @yield [report] Reports from the ffmpeg command (see FFMPEG::Reporters).
     # @return [FFMPEG::Status]
-    def ffmpeg_execute(*args, status: nil, reporters: nil, timeout: nil)
+    def ffmpeg_execute(*args, status: nil, reporters: nil, timeout: nil, spawn: nil)
       status ||= FFMPEG::Status.new
       reporters ||= self.reporters
       timeout ||= self.timeout
 
       status.bind! do
-        ffmpeg_popen3(*args) do |_stdin, stdout, stderr, wait_thr|
+        spawn ||= {}
+        ffmpeg_popen3(*args, spawn:) do |_stdin, stdout, stderr, wait_thr|
           Timeout.timeout(timeout) do
             stderr.each(chomp: true) do |line|
               reporter = reporters.find { |r| r.match?(line) }
@@ -171,10 +177,11 @@ def ffmpeg_execute(*args, status: nil, reporters: nil, timeout: nil)
     #
     # @param args [Array<String>] The arguments to pass to ffmpeg.
     # @param reporters [Array<FFMPEG::Reporters::Output>] The reporters to use to parse the output.
+    # @param spawn [Hash] Options hash forwarded to Process.spawn
     # @yield [report] Reports from the ffmpeg command (see FFMPEG::Reporters).
     # @return [FFMPEG::Status]
-    def ffmpeg_execute!(*args, status: nil, reporters: nil, timeout: nil)
-      ffmpeg_execute(*args, status:, reporters:, timeout:).assert!
+    def ffmpeg_execute!(*args, status: nil, reporters: nil, timeout: nil, spawn: nil)
+      ffmpeg_execute(*args, status:, reporters:, timeout:, spawn:).assert!
     end
 
     # Get the path to the ffprobe binary.
@@ -205,9 +212,10 @@ def ffprobe_binary=(path)
     # @param args [Array<String>] The arguments to pass to ffprobe.
     # @return [Array<String, Process::Status>] The standard output, the standard error, and the process status.
     # @raise [Errno::ENOENT] If the ffprobe binary cannot be found.
-    def ffprobe_capture3(*args)
+    def ffprobe_capture3(*args, spawn: nil)
       logger.debug(self) { "ffprobe -y #{Shellwords.join(args)}" }
-      FFMPEG::IO.capture3(ffprobe_binary, '-y', *args)
+      spawn ||= {}
+      FFMPEG::IO.capture3(ffprobe_binary, '-y', *args, **spawn)
     end
 
     # Starts a new ffprobe process with the given arguments.
@@ -216,14 +224,16 @@ def ffprobe_capture3(*args)
     # to the specified block.
     #
     # @param args [Array<String>] The arguments to pass to ffprobe.
+    # @param spawn [Hash] Options hash forwarded to Process.spawn
     # @yieldparam stdin (+IO+) The standard input stream.
     # @yieldparam stdout (+FFMPEG::IO+) The standard output stream.
     # @yieldparam stderr (+FFMPEG::IO+) The standard error stream.
     # @return [Process::Status, Array<IO, Thread>]
     # @raise [Errno::ENOENT] If the ffprobe binary cannot be found.
-    def ffprobe_popen3(*args, &)
+    def ffprobe_popen3(*args, spawn: nil, &)
       logger.debug(self) { "ffprobe -y #{Shellwords.join(args)}" }
-      FFMPEG::IO.popen3(ffprobe_binary, '-y', *args, &)
+      spawn ||= {}
+      FFMPEG::IO.popen3(ffprobe_binary, '-y', *args, **spawn, &)
     end
 
     # Cross-platform way of finding an executable in the $PATH.

lib/ffmpeg/io.rb

@@ -30,15 +30,15 @@ def extend!(io)
         io.extend(FFMPEG::IO)
       end
 
-      def capture3(*cmd)
-        *io, status = Open3.capture3(*cmd)
+      def capture3(*cmd, **spawn_opts)
+        *io, status = Open3.capture3(*cmd, **spawn_opts)
         io.each(&method(:encode!))
         [*io, status]
       end
 
-      def popen3(*cmd, &block)
+      def popen3(*cmd, **spawn_opts, &block)
         if block_given?
-          Open3.popen3(*cmd) do |*io, wait_thr|
+          Open3.popen3(*cmd, **spawn_opts) do |*io, wait_thr|
             io = io.map(&method(:extend!))
             block.call(*io, wait_thr)
           rescue StandardError
@@ -47,7 +47,7 @@ def popen3(*cmd, &block)
             raise
           end
         else
-          *io, wait_thr = Open3.popen3(*cmd)
+          *io, wait_thr = Open3.popen3(*cmd, **spawn_opts)
           io = io.map(&method(:extend!))
           [*io, wait_thr]
         end

lib/ffmpeg/media.rb

@@ -530,8 +530,10 @@ def local?
     # @param inargs [Array<String>] The arguments to pass before the input.
     # @yield [report] Reports from the ffmpeg command (see FFMPEG::Reporters).
     # @return [Process::Status]
-    def ffmpeg_execute(*args, inargs: [], status: nil, reporters: nil, timeout: nil, &block)
-      FFMPEG.ffmpeg_execute(*inargs, '-i', path, *args, status:, reporters:, timeout:, &block)
+    def ffmpeg_execute(*args, inargs: [], status: nil, reporters: nil, timeout: nil,
+                       spawn: nil, &block)
+      FFMPEG.ffmpeg_execute(*inargs, '-i', path, *args, status:, reporters:, timeout:,
+                                                        spawn:, &block)
     end
 
     # Execute a ffmpeg command with the media as input
@@ -541,8 +543,9 @@ def ffmpeg_execute(*args, inargs: [], status: nil, reporters: nil, timeout: nil,
     # @param inargs [Array<String>] The arguments to pass before the input.
     # @yield [report] Reports from the ffmpeg command (see FFMPEG::Reporters).
     # @return [Process::Status]
-    def ffmpeg_execute!(*args, inargs: [], status: nil, reporters: nil, timeout: nil, &block)
-      ffmpeg_execute(*args, inargs:, status:, reporters:, timeout:, &block).assert!
+    def ffmpeg_execute!(*args, inargs: [], status: nil, reporters: nil, timeout: nil,
+                        spawn: nil, &block)
+      ffmpeg_execute(*args, inargs:, status:, reporters:, timeout:, spawn:, &block).assert!
     end
   end
 end

lib/ffmpeg/transcoder.rb

@@ -98,9 +98,10 @@ def initialize(
     #
     # @param media [String, Pathname, URI, FFMPEG::Media] The media file to transcode.
     # @param output_path [String, Pathname] The output path to save the transcoded files.
+    # @param chdir [String, Pathname] Change the ffmpeg working directory
     # @yield The block to execute to report the transcoding process.
     # @return [FFMPEG::Transcoder::Status] The status of the transcoding process.
-    def process(media, output_path, &)
+    def process(media, output_path, chdir: nil, &)
       status = nil
 
       attempts = 0
@@ -126,11 +127,13 @@ def process(media, output_path, &)
         end
 
         inargs = CommandArgs.compose(media, context:, &@compose_inargs).to_a
+        spawn = chdir ? { chdir: } : {}
         status = media.ffmpeg_execute(
           *args,
           inargs:,
           reporters:,
           timeout:,
+          spawn:,
           status: Status.new(output_paths, checks:),
           &
         )
@@ -148,10 +151,11 @@ def process(media, output_path, &)
     #
     # @param media [String, Pathname, URI, FFMPEG::Media] The media file to transcode.
     # @param output_path [String, Pathname] The output path to save the transcoded files.
+    # @param chdir [String, Pathname] Change the ffmpeg working directory
     # @yield The block to execute to report the transcoding process.
     # @return [FFMPEG::Transcoder::Status] The status of the transcoding process.
-    def process!(media, output_path, &)
-      process(media, output_path, &).assert!
+    def process!(media, output_path, chdir: nil, &)
+      process(media, output_path, chdir:, &).assert!
     end
   end
 end

spec/ffmpeg/media_spec.rb

@@ -625,7 +625,7 @@ module FFMPEG
         block = proc {}
 
         expect(status).to receive(:assert!).and_return(status)
-        expect(subject).to receive(:ffmpeg_execute).with(*args, inargs:, status:, reporters:, timeout:,
+        expect(subject).to receive(:ffmpeg_execute).with(*args, inargs:, status:, reporters:, timeout:, spawn: nil,
                                                          &block).and_return(status)
         expect(subject.ffmpeg_execute!(*args, inargs:, status:, reporters:, timeout:, &block)).to be(status)
       end

spec/ffmpeg/transcoder_spec.rb

@@ -117,6 +117,17 @@ module FFMPEG
           expect(attempts).to eq(2)
         end
       end
+
+      it 'can run ffmpeg in a different working directory (chdir)' do
+        output_path = File.join(tmp_dir, SecureRandom.hex(4))
+        status = double(Transcoder::Status, success?: true)
+
+        expect(FFMPEG::IO).to receive(:popen3)
+          .with(any_args, chdir: tmp_dir)
+          .and_return(status)
+
+        subject.process(media, output_path, chdir: tmp_dir)
+      end
     end
 
     describe '#process!' do
@@ -127,7 +138,9 @@ module FFMPEG
         block = proc {}
 
         expect(status).to receive(:assert!).and_return(status)
-        expect(subject).to receive(:process).with(media, output_path, &block).and_return(status)
+        expect(subject).to receive(:process)
+          .with(media, output_path, chdir: nil, &block)
+          .and_return(status)
         expect(subject.process!(media, output_path, &block)).to eq(status)
       end
     end

spec/ffmpeg_spec.rb

@@ -61,6 +61,13 @@
       expect(status.exitstatus).to eq(0)
     end
 
+    it 'forwards spawn parameter to popen3' do
+      spawn = { chdir: '/tmp/test' }
+
+      expect(FFMPEG::IO).to receive(:popen3).with(any_args, chdir: '/tmp/test')
+      described_class.ffmpeg_execute(spawn:)
+    end
+
     context 'when ffmpeg hangs' do
       before do
         described_class.ffmpeg_binary = fixture_file('bin/mock-ffmpeg')