gs: add source and sink for Google Cloud Storage

Useful when having a service that runs a GStreamer pipeline
or application in Google Cloud to avoid storing the inputs
and outputs in the running container or service. For example
when analyzing a video from a Google Cloud Storage bucket
and extracting images or converting the video and then uploading
the results into another Google Cloud Storage bucket.

- gssrc allows to read from a file located in Google Cloud
Storage and it supports seeking.
- gssink allows to write to a file located in Google Cloud
Storage. There are 2 modes, one similar to multifilesink and
the other similar to filesink.

Example:
  gst-launch-1.0 gssrc location=gs://mybucket/videos/sample.mp4 ! decodebin ! glimagesink
  gst-launch-1.0 playbin uri=gs://mybucket/videos/sample.mp4
  gst-launch-1.0 videotestsrc num-buffers=5 ! pngenc ! gssink object-name="img/img%05d.png" bucket-name="mybucket" next-file=buffer
  gst-launch-1.0 filesrc location=sample.mp4 ! gssink object-name="videos/video.mp4" bucket-name="mybucket" next-file=none

When running locally simply set GOOGLE_APPLICATION_CREDENTIALS. But
when running in Google Cloud Run or Google Cloud Engine, just set the
"service-account-email" property on each element.

Closes #1264

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1369>

1 files changed, 56 insertions, 0 deletions

diff --git a/ext/gs/gstgs.cpp b/ext/gs/gstgs.cpp
new file mode 100644
index 000000000..f5c9ddfaf
--- /dev/null
+++ b/ext/gs/gstgs.cpp
@@ -0,0 +1,56 @@
+/* GStreamer
+ * Copyright (C) 2020 Julien Isorce <jisorce@oblong.com>
+ *
+ * gstgssrc.c:
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+/**
+ * plugin-gs:
+ *
+ * The gs plugin contains elements to interact with with Google Cloud Storage.
+ * In particular with the gs:// protocol or by specifying the storage bucket.
+ *
+ * Since: 1.20
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstgssink.h"
+#include "gstgssrc.h"
+
+GST_DEBUG_CATEGORY (gst_gs_src_debug);
+
+static gboolean
+plugin_init (GstPlugin * plugin)
+{
+  if (!gst_element_register (plugin, "gssrc", GST_RANK_NONE, GST_TYPE_GS_SRC))
+    return FALSE;
+
+  if (!gst_element_register (plugin, "gssink", GST_RANK_NONE, GST_TYPE_GS_SINK))
+    return FALSE;
+
+  return TRUE;
+}
+
+GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
+    GST_VERSION_MINOR,
+    gs,
+    "Read and write from and to a Google Cloud Storage",
+    plugin_init,
+    PACKAGE_VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)