This patch implements the REST API's for POST /channels/{channelId}/play

and GET /playback/{playbackId}.

This allows an external application to initiate playback of a sound on a
channel while the channel is in the Stasis application.

/play commands are issued asynchronously, and return immediately with
the URL of the associated /playback resource. Playback commands queue up,
playing in succession. The /playback resource shows the state of a
playback operation as enqueued, playing or complete. (Although the
operation will only be in the 'complete' state for a very short time,
since it is almost immediately freed up).

(closes issue ASTERISK-21283)
(closes issue ASTERISK-21586)
Review: https://reviewboard.asterisk.org/r/2531/



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@389587 65c4cc65-6c06-0410-ace0-fbb531ad65f3

4 files changed, 168 insertions, 3 deletions

diff --git a/include/asterisk/app.h b/include/asterisk/app.h
index 75d1fbb7e..2089bced9 100644
--- a/include/asterisk/app.h
+++ b/include/asterisk/app.h
@@ -636,14 +636,19 @@ int ast_linear_stream(struct ast_channel *chan, const char *filename, int fd, in
 
 /*!
  * \brief Stream a file with fast forward, pause, reverse, restart.
- * \param chan
- * \param file filename
- * \param fwd, rev, stop, pause, restart, skipms, offsetms
+ * \param chan Channel
+ * \param file File to play.
+ * \param fwd, rev, stop, pause, restart DTMF keys for media control
+ * \param skipms Number of milliseconds to skip for fwd/rev.
+ * \param offsetms Number of milliseconds to skip when starting the media.
  *
  * Before calling this function, set this to be the number
  * of ms to start from the beginning of the file.  When the function
  * returns, it will be the number of ms from the beginning where the
  * playback stopped.  Pass NULL if you don't care.
+ *
+ * \retval 0 on success
+ * \retval Non-zero on failure
  */
 int ast_control_streamfile(struct ast_channel *chan, const char *file, const char *fwd, const char *rev, const char *stop, const char *pause, const char *restart, int skipms, long *offsetms);
 
diff --git a/include/asterisk/stasis_app_playback.h b/include/asterisk/stasis_app_playback.h
new file mode 100644
index 000000000..598c6be59
--- /dev/null
+++ b/include/asterisk/stasis_app_playback.h
@@ -0,0 +1,117 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 2013, Digium, Inc.
+ *
+ * David M. Lee, II <dlee@digium.com>
+ *
+ * See http://www.asterisk.org for more information about
+ * the Asterisk project. Please do not directly contact
+ * any of the maintainers of this project for assistance;
+ * the project provides a web site, mailing lists and IRC
+ * channels for your use.
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+
+#ifndef _ASTERISK_STASIS_APP_PLAYBACK_H
+#define _ASTERISK_STASIS_APP_PLAYBACK_H
+
+/*! \file
+ *
+ * \brief Stasis Application Playback API. See \ref res_stasis "Stasis
+ * Application API" for detailed documentation.
+ *
+ * \author David M. Lee, II <dlee@digium.com>
+ * \since 12
+ */
+
+#include "asterisk/stasis_app.h"
+
+/*! Opaque struct for handling the playback of a single file */
+struct stasis_app_playback;
+
+/*! State of a playback operation */
+enum stasis_app_playback_state {
+	/*! The playback has not started yet */
+	STASIS_PLAYBACK_STATE_QUEUED,
+	/*! The media is currently playing */
+	STASIS_PLAYBACK_STATE_PLAYING,
+	/*! The media has stopped playing */
+	STASIS_PLAYBACK_STATE_COMPLETE,
+};
+
+enum stasis_app_playback_media_control {
+	STASIS_PLAYBACK_STOP,
+	STASIS_PLAYBACK_PAUSE,
+	STASIS_PLAYBACK_PLAY,
+	STASIS_PLAYBACK_REWIND,
+	STASIS_PLAYBACK_FAST_FORWARD,
+	STASIS_PLAYBACK_SPEED_UP,
+	STASIS_PLAYBACK_SLOW_DOWN,
+};
+
+/*!
+ * \brief Play a file to the control's channel.
+ *
+ * Note that the file isn't the full path to the file. Asterisk's internal
+ * playback mechanism will automagically select the best format based on the
+ * available codecs for the channel.
+ *
+ * \param control Control for \c res_stasis.
+ * \param file Base filename for the file to play.
+ * \return Playback control object.
+ * \return \c NULL on error.
+ */
+struct stasis_app_playback *stasis_app_control_play_uri(
+	struct stasis_app_control *control, const char *file,
+	const char *language);
+
+/*!
+ * \brief Gets the current state of a playback operation.
+ *
+ * \param playback Playback control object.
+ * \return The state of the \a playback object.
+ */
+enum stasis_app_playback_state stasis_app_playback_get_state(
+	struct stasis_app_playback *playback);
+
+/*!
+ * \brief Gets the unique id of a playback object.
+ *
+ * \param playback Playback control object.
+ * \return \a playback's id.
+ * \return \c NULL if \a playback ic \c NULL
+ */
+const char *stasis_app_playback_get_id(
+	struct stasis_app_playback *playback);
+
+/*!
+ * \brief Finds the playback object with the given id.
+ *
+ * \param id Id of the playback object to find.
+ * \return Associated \ref stasis_app_playback object.
+ * \return \c NULL if \a id not found.
+ */
+struct ast_json *stasis_app_playback_find_by_id(const char *id);
+
+/*!
+ * \brief Controls the media for a given playback operation.
+ *
+ * \param playback Playback control object.
+ * \param control Media control operation.
+ * \return 0 on success
+ * \return non-zero on error.
+ */
+int stasis_app_playback_control(struct stasis_app_playback *playback,
+	enum stasis_app_playback_media_control control);
+
+/*!
+ * \brief Message type for playback updates. The data is an
+ * \ref ast_channel_blob.
+ */
+struct stasis_message_type *stasis_app_playback_snapshot_type(void);
+
+#endif /* _ASTERISK_STASIS_APP_PLAYBACK_H */
diff --git a/include/asterisk/stasis_channels.h b/include/asterisk/stasis_channels.h
index 5ead93d3a..dace99af5 100644
--- a/include/asterisk/stasis_channels.h
+++ b/include/asterisk/stasis_channels.h
@@ -54,6 +54,7 @@ struct ast_channel_snapshot {
 		AST_STRING_FIELD(caller_number);	/*!< Caller ID Number */
 		AST_STRING_FIELD(connected_name);	/*!< Connected Line Name */
 		AST_STRING_FIELD(connected_number);	/*!< Connected Line Number */
+		AST_STRING_FIELD(language);		/*!< The default spoken language for the channel */
 	);
 
 	struct timeval creationtime;	/*!< The time of channel creation */
@@ -124,6 +125,17 @@ struct ast_channel_snapshot *ast_channel_snapshot_create(
 
 /*!
  * \since 12
+ * \brief Get the most recent snapshot for channel with the given \a uniqueid.
+ *
+ * \param uniqueid Uniqueid of the snapshot to fetch.
+ * \return Most recent channel snapshot
+ * \return \c NULL on error
+ */
+struct ast_channel_snapshot *ast_channel_snapshot_get_latest(
+	const char *uniqueid);
+
+/*!
+ * \since 12
  * \brief Creates a \ref ast_channel_blob message.
  *
  * The given \a blob should be treated as immutable and not modified after it is
@@ -142,6 +154,23 @@ struct stasis_message *ast_channel_blob_create(struct ast_channel *chan,
 
 /*!
  * \since 12
+ * \brief Create a \ref ast_channel_blob message, pulling channel state from
+ *        the cache.
+ *
+ * \param uniqueid Uniqueid of the channel.
+ * \param type Message type for this blob.
+ * \param blob JSON object representing the data, or \c NULL for no data. If
+ *             \c NULL, ast_json_null() is put into the object.
+ *
+ * \return \ref ast_channel_blob message.
+ * \return \c NULL on error
+ */
+struct stasis_message *ast_channel_blob_create_from_cache(
+	const char *uniqueid, struct stasis_message_type *type,
+	struct ast_json *blob);
+
+/*!
+ * \since 12
  * \brief Create a \ref ast_multi_channel_blob suitable for a \ref stasis_message.
  *
  * The given \a blob should be treated as immutable and not modified after it is
@@ -223,6 +252,14 @@ void ast_multi_channel_blob_add_channel(struct ast_multi_channel_blob *obj,
 
 /*!
  * \since 12
+ * \brief Publish a \ref ast_channel_snapshot for a channel.
+ *
+ * \param chan Channel to publish.
+ */
+void ast_channel_publish_snapshot(struct ast_channel *chan);
+
+/*!
+ * \since 12
  * \brief Publish a \ref ast_channel_varset for a channel.
  *
  * \param chan Channel to pulish the event for, or \c NULL for 'none'.
diff --git a/include/asterisk/stasis_http.h b/include/asterisk/stasis_http.h
index cc0ceeee4..f81a206e6 100644
--- a/include/asterisk/stasis_http.h
+++ b/include/asterisk/stasis_http.h
@@ -163,6 +163,12 @@ void stasis_http_response_ok(struct stasis_http_response *response,
 void stasis_http_response_no_content(struct stasis_http_response *response);
 
 /*!
+ * \brief Fill in a <tt>Created</tt> (201) \a stasis_http_response.
+ */
+void stasis_http_response_created(struct stasis_http_response *response,
+	const char *url);
+
+/*!
  * \brief Fill in \a response with a 500 message for allocation failures.
  * \param response Response to fill in.
  */