[libcast] Adds Cast folder structure.

This adds a basic folder structure for libcast code with README files and DEPS
to enforce component layering per the design doc.

Change-Id: I42555ae1f6b5f696bbbd4a8859da801740382304
Reviewed-on: https://chromium-review.googlesource.com/c/openscreen/+/1592675
Commit-Queue: mark a. foltz <mfoltz@chromium.org>
Reviewed-by: Max Yakimakha <yakimakha@google.com>
Reviewed-by: Brandon Tolsch <btolsch@chromium.org>

16 files changed, 118 insertions, 0 deletions

diff --git a/DEPS b/DEPS
index 444ddeca..c33dd151 100644
--- a/DEPS
+++ b/DEPS
@@ -91,6 +91,8 @@ recursedeps = [
     'third_party/chromium_quic/src',
 ]
 
+# TODO(mfoltz): Change to allow only base and third_party from the top level
+# once OSP code is moved into osp/.
 include_rules = [
     '+api',
     '+osp_base',
diff --git a/cast/DEPS b/cast/DEPS
new file mode 100644
index 00000000..e8615f96
--- /dev/null
+++ b/cast/DEPS
@@ -0,0 +1,17 @@
+# -*- Mode: Python; -*-
+
+include_rules = [
+  # OSP code is strictly verboten.
+  '-api',
+  '-demo',
+  '-discovery',
+  '-go',
+  '-msgs',
+
+  # Intra-libcast dependencies must be explicit.
+  '-cast',
+
+  # All libcast code can use platform and cast/third_party.
+  '+cast/third_party',
+  '+platform'
+]
diff --git a/cast/README.md b/cast/README.md
new file mode 100644
index 00000000..1b890c5b
--- /dev/null
+++ b/cast/README.md
@@ -0,0 +1,5 @@
+# libcast
+
+libcast is an open source implementation of the Cast procotol supporting Cast
+applications and streaming to Cast-compatible devices.
+
diff --git a/cast/common/DEPS b/cast/common/DEPS
new file mode 100644
index 00000000..e1023950
--- /dev/null
+++ b/cast/common/DEPS
@@ -0,0 +1,6 @@
+# -*- Mode: Python; -*-
+
+include_rules = [
+   # libcast common code must depend on neither the sender nor the receiver.
+   '+cast/common'
+]
diff --git a/cast/common/public/DEPS b/cast/common/public/DEPS
new file mode 100644
index 00000000..7060c480
--- /dev/null
+++ b/cast/common/public/DEPS
@@ -0,0 +1,12 @@
+# -*- Mode: Python; -*-
+
+include_rules = [
+  # By default, openscreen implementation libraries should not be exposed
+  # through public APIs.
+  '-base',
+  '-platform',
+
+  # Dependencies on the implementation are not allowed in public/.
+  '-cast/common',
+  '+cast/common/public'
+]
diff --git a/cast/common/public/README.md b/cast/common/public/README.md
new file mode 100644
index 00000000..02043599
--- /dev/null
+++ b/cast/common/public/README.md
@@ -0,0 +1,3 @@
+# cast/common/public
+
+This component contains code shared between the sender and receiver modules of libcast.
diff --git a/cast/receiver/DEPS b/cast/receiver/DEPS
new file mode 100644
index 00000000..7bdadde7
--- /dev/null
+++ b/cast/receiver/DEPS
@@ -0,0 +1,7 @@
+# -*- Mode: Python; -*-
+
+include_rules = [
+   # libcast receiver code must not depend on the sender.
+   '+cast/common/public',
+   '+cast/receiver'
+]
diff --git a/cast/receiver/public/DEPS b/cast/receiver/public/DEPS
new file mode 100644
index 00000000..714c37a4
--- /dev/null
+++ b/cast/receiver/public/DEPS
@@ -0,0 +1,12 @@
+# -*- Mode: Python; -*-
+
+include_rules = [
+  # By default, openscreen implementation libraries should not be exposed
+  # through public APIs.
+  '-base',
+  '-platform',
+
+  # Dependencies on the implementation are not allowed in public/.
+  '-cast/receiver',
+  '+cast/receiver/public'
+]
diff --git a/cast/receiver/public/README.md b/cast/receiver/public/README.md
new file mode 100644
index 00000000..cba74b54
--- /dev/null
+++ b/cast/receiver/public/README.md
@@ -0,0 +1,4 @@
+# cast/receiver/public
+
+This module contains an implementation of the Cast "receiver", i.e. the server
+on a Cast device that receives requests to launch apps.
diff --git a/cast/sender/DEPS b/cast/sender/DEPS
new file mode 100644
index 00000000..e386f11a
--- /dev/null
+++ b/cast/sender/DEPS
@@ -0,0 +1,7 @@
+# -*- Mode: Python; -*-
+
+include_rules = [
+   # libcast sender code must not depend on the receiver.
+   '+cast/common/public',
+   '+cast/sender'
+]
diff --git a/cast/sender/public/DEPS b/cast/sender/public/DEPS
new file mode 100644
index 00000000..44de6584
--- /dev/null
+++ b/cast/sender/public/DEPS
@@ -0,0 +1,12 @@
+# -*- Mode: Python; -*-
+
+include_rules = [
+  # By default, openscreen implementation libraries should not be exposed
+  # through public APIs.
+  '-base',
+  '-platform',
+
+  # Dependencies on the implementation are not allowed in public/.
+  '-cast/sender',
+  '+cast/sender/public'
+]
diff --git a/cast/sender/public/README.md b/cast/sender/public/README.md
new file mode 100644
index 00000000..ace86163
--- /dev/null
+++ b/cast/sender/public/README.md
@@ -0,0 +1,5 @@
+# cast/receiver/public
+
+This module contains an implementation of the Cast "sender", i.e. the client
+that discovers Cast devices on the LAN and launches apps on them.
+
diff --git a/cast/streaming/DEPS b/cast/streaming/DEPS
new file mode 100644
index 00000000..6a332471
--- /dev/null
+++ b/cast/streaming/DEPS
@@ -0,0 +1,10 @@
+# -*- Mode: Python; -*-
+
+# In the future, the streaming code will likely split into sender and receiver
+# modules, at which point this can become finer-grained.
+include_rules = [
+  '+cast/common',
+  '+cast/receiver',
+  '+cast/sender',
+  '+cast/streaming'
+]
diff --git a/cast/streaming/README.md b/cast/streaming/README.md
new file mode 100644
index 00000000..a34f9ca2
--- /dev/null
+++ b/cast/streaming/README.md
@@ -0,0 +1,4 @@
+# cast/streaming
+
+This module contains an implementation of Cast Streaming, a real-time media
+streaming protocol between Cast senders and Cast receivers.
diff --git a/cast/third_party/DEPS b/cast/third_party/DEPS
new file mode 100644
index 00000000..33d2a399
--- /dev/null
+++ b/cast/third_party/DEPS
@@ -0,0 +1,8 @@
+# -*- Mode: Python; -*-
+
+include_rules = [
+  # No dependencies on libcast.
+  '-base',
+  '-platform',
+  '-third_party'
+]
diff --git a/cast/third_party/README.md b/cast/third_party/README.md
new file mode 100644
index 00000000..ce4cc5cf
--- /dev/null
+++ b/cast/third_party/README.md
@@ -0,0 +1,4 @@
+# cast/third_party
+
+Directory for third party dependencies of libcast.
+