asterisk/res/ari/resource_channels.c

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2012 - 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.
 */

/*! \file
 *
 * \brief Implementation for ARI stubs.
 *
 * \author David M. Lee, II <dlee@digium.com>
 */

/*** MODULEINFO
	<depend type="module">res_stasis_app_playback</depend>
	<support_level>core</support_level>
 ***/

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision$")

#include "asterisk/file.h"
#include "asterisk/pbx.h"
#include "asterisk/bridge.h"
#include "asterisk/callerid.h"
#include "asterisk/stasis_app.h"
#include "asterisk/stasis_app_playback.h"
#include "asterisk/stasis_app_recording.h"
#include "asterisk/stasis_app_snoop.h"
#include "asterisk/stasis_channels.h"
#include "asterisk/causes.h"
#include "resource_channels.h"

#include <limits.h>

/*!
 * \brief Finds the control object for a channel, filling the response with an
 * error, if appropriate.
 * \param[out] response Response to fill with an error if control is not found.
 * \param channel_id ID of the channel to lookup.
 * \return Channel control object.
 * \return \c NULL if control object does not exist.
 */
static struct stasis_app_control *find_control(
	struct ast_ari_response *response,
	const char *channel_id)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	ast_assert(response != NULL);

	control = stasis_app_control_find_by_channel_id(channel_id);
	if (control == NULL) {
		/* Distinguish between 404 and 409 errors */
		RAII_VAR(struct ast_channel *, chan, NULL, ao2_cleanup);
		chan = ast_channel_get_by_name(channel_id);
		if (chan == NULL) {
			ast_ari_response_error(response, 404, "Not Found",
				   "Channel not found");
			return NULL;
		}

		ast_ari_response_error(response, 409, "Conflict",
			   "Channel not in Stasis application");
		return NULL;
	}

	ao2_ref(control, +1);
	return control;
}

void ast_ari_channels_continue_in_dialplan(
	struct ast_variable *headers,
	struct ast_ari_channels_continue_in_dialplan_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	ast_assert(response != NULL);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		return;
	}

	if (stasis_app_control_continue(control, args->context, args->extension, args->priority)) {
		ast_ari_response_alloc_failed(response);
		return;
	}

	ast_ari_response_no_content(response);
}

void ast_ari_channels_answer(struct ast_variable *headers,
	struct ast_ari_channels_answer_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		return;
	}

	if (stasis_app_control_answer(control) != 0) {
		ast_ari_response_error(
			response, 500, "Internal Server Error",
			"Failed to answer channel");
		return;
	}

	ast_ari_response_no_content(response);
}

void ast_ari_channels_ring(struct ast_variable *headers,
	struct ast_ari_channels_ring_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		return;
	}

	stasis_app_control_ring(control);

	ast_ari_response_no_content(response);
}

void ast_ari_channels_ring_stop(struct ast_variable *headers,
	struct ast_ari_channels_ring_stop_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		return;
	}

	stasis_app_control_ring_stop(control);

	ast_ari_response_no_content(response);
}

void ast_ari_channels_mute(struct ast_variable *headers,
	struct ast_ari_channels_mute_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);
	unsigned int direction = 0;
	enum ast_frame_type frametype = AST_FRAME_VOICE;

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		return;
	}

	if (ast_strlen_zero(args->direction)) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Direction is required");
		return;
	}

	if (!strcmp(args->direction, "in")) {
		direction = AST_MUTE_DIRECTION_READ;
	} else if (!strcmp(args->direction, "out")) {
		direction = AST_MUTE_DIRECTION_WRITE;
	} else if (!strcmp(args->direction, "both")) {
		direction = AST_MUTE_DIRECTION_READ | AST_MUTE_DIRECTION_WRITE;
	} else {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Invalid direction specified");
		return;
	}

	stasis_app_control_mute(control, direction, frametype);

	ast_ari_response_no_content(response);
}

void ast_ari_channels_unmute(struct ast_variable *headers,
	struct ast_ari_channels_unmute_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);
	unsigned int direction = 0;
	enum ast_frame_type frametype = AST_FRAME_VOICE;

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		return;
	}

	if (ast_strlen_zero(args->direction)) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Direction is required");
		return;
	}

	if (!strcmp(args->direction, "in")) {
		direction = AST_MUTE_DIRECTION_READ;
	} else if (!strcmp(args->direction, "out")) {
		direction = AST_MUTE_DIRECTION_WRITE;
	} else if (!strcmp(args->direction, "both")) {
		direction = AST_MUTE_DIRECTION_READ | AST_MUTE_DIRECTION_WRITE;
	} else {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Invalid direction specified");
		return;
	}

	stasis_app_control_unmute(control, direction, frametype);

	ast_ari_response_no_content(response);
}

void ast_ari_channels_send_dtmf(struct ast_variable *headers,
	struct ast_ari_channels_send_dtmf_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		return;
	}

	if (ast_strlen_zero(args->dtmf)) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"DTMF is required");
		return;
	}

	stasis_app_control_dtmf(control, args->dtmf, args->before, args->between, args->duration, args->after);

	ast_ari_response_no_content(response);
}

void ast_ari_channels_hold(struct ast_variable *headers,
	struct ast_ari_channels_hold_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		/* Response filled in by find_control */
		return;
	}

	stasis_app_control_hold(control);

	ast_ari_response_no_content(response);
}

void ast_ari_channels_unhold(struct ast_variable *headers,
	struct ast_ari_channels_unhold_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		/* Response filled in by find_control */
		return;
	}

	stasis_app_control_unhold(control);

	ast_ari_response_no_content(response);
}

void ast_ari_channels_start_moh(struct ast_variable *headers,
	struct ast_ari_channels_start_moh_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		/* Response filled in by find_control */
		return;
	}

	stasis_app_control_moh_start(control, args->moh_class);
	ast_ari_response_no_content(response);
}

void ast_ari_channels_stop_moh(struct ast_variable *headers,
	struct ast_ari_channels_stop_moh_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		/* Response filled in by find_control */
		return;
	}

	stasis_app_control_moh_stop(control);
	ast_ari_response_no_content(response);
}

void ast_ari_channels_start_silence(struct ast_variable *headers,
	struct ast_ari_channels_start_silence_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		/* Response filled in by find_control */
		return;
	}

	stasis_app_control_silence_start(control);
	ast_ari_response_no_content(response);
}

void ast_ari_channels_stop_silence(struct ast_variable *headers,
	struct ast_ari_channels_stop_silence_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		/* Response filled in by find_control */
		return;
	}

	stasis_app_control_silence_stop(control);
	ast_ari_response_no_content(response);
}

void ast_ari_channels_play(struct ast_variable *headers,
	struct ast_ari_channels_play_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);
	RAII_VAR(struct ast_channel_snapshot *, snapshot, NULL, ao2_cleanup);
	RAII_VAR(struct stasis_app_playback *, playback, NULL, ao2_cleanup);
	RAII_VAR(char *, playback_url, NULL, ast_free);
	struct ast_json *json;
	const char *language;

	ast_assert(response != NULL);

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		/* Response filled in by find_control */
		return;
	}

	snapshot = stasis_app_control_get_snapshot(control);
	if (!snapshot) {
		ast_ari_response_error(
			response, 404, "Not Found",
			"Channel not found");
		return;
	}

	if (args->skipms < 0) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"skipms cannot be negative");
		return;
	}

	if (args->offsetms < 0) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"offsetms cannot be negative");
		return;
	}

	language = S_OR(args->lang, snapshot->language);

	playback = stasis_app_control_play_uri(control, args->media, language,
		args->channel_id, STASIS_PLAYBACK_TARGET_CHANNEL, args->skipms, args->offsetms);
	if (!playback) {
		ast_ari_response_error(
			response, 500, "Internal Server Error",
			"Failed to queue media for playback");
		return;
	}

	ast_asprintf(&playback_url, "/playback/%s",
		stasis_app_playback_get_id(playback));
	if (!playback_url) {
		ast_ari_response_error(
			response, 500, "Internal Server Error",
			"Out of memory");
		return;
	}

	json = stasis_app_playback_to_json(playback);
	if (!json) {
		ast_ari_response_error(
			response, 500, "Internal Server Error",
			"Out of memory");
		return;
	}

	ast_ari_response_created(response, playback_url, json);
}

void ast_ari_channels_record(struct ast_variable *headers,
	struct ast_ari_channels_record_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);
	RAII_VAR(struct ast_channel_snapshot *, snapshot, NULL, ao2_cleanup);
	RAII_VAR(struct stasis_app_recording *, recording, NULL, ao2_cleanup);
	RAII_VAR(char *, recording_url, NULL, ast_free);
	struct ast_json *json;
	RAII_VAR(struct stasis_app_recording_options *, options, NULL,
		ao2_cleanup);
	RAII_VAR(char *, uri_encoded_name, NULL, ast_free);
	size_t uri_name_maxlen;

	ast_assert(response != NULL);

	if (args->max_duration_seconds < 0) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"max_duration_seconds cannot be negative");
		return;
	}

	if (args->max_silence_seconds < 0) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"max_silence_seconds cannot be negative");
		return;
	}

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		/* Response filled in by find_control */
		return;
	}

	options = stasis_app_recording_options_create(args->name, args->format);
	if (options == NULL) {
		ast_ari_response_error(
			response, 500, "Internal Server Error",
			"Out of memory");
	}
	options->max_silence_seconds = args->max_silence_seconds;
	options->max_duration_seconds = args->max_duration_seconds;
	options->terminate_on =
		stasis_app_recording_termination_parse(args->terminate_on);
	options->if_exists =
		stasis_app_recording_if_exists_parse(args->if_exists);
	options->beep = args->beep;

	if (options->terminate_on == STASIS_APP_RECORDING_TERMINATE_INVALID) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"terminateOn invalid");
		return;
	}

	if (options->if_exists == -1) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"ifExists invalid");
		return;
	}

	if (!ast_get_format_for_file_ext(options->format)) {
		ast_ari_response_error(
			response, 422, "Unprocessable Entity",
			"specified format is unknown on this system");
		return;
	}

	recording = stasis_app_control_record(control, options);
	if (recording == NULL) {
		switch(errno) {
		case EINVAL:
			/* While the arguments are invalid, we should have
			 * caught them prior to calling record.
			 */
			ast_ari_response_error(
				response, 500, "Internal Server Error",
				"Error parsing request");
			break;
		case EEXIST:
			ast_ari_response_error(response, 409, "Conflict",
				"Recording '%s' already exists and can not be overwritten",
				args->name);
			break;
		case ENOMEM:
			ast_ari_response_error(
				response, 500, "Internal Server Error",
				"Out of memory");
			break;
		case EPERM:
			ast_ari_response_error(
				response, 400, "Bad Request",
				"Recording name invalid");
			break;
		default:
			ast_log(LOG_WARNING,
				"Unrecognized recording error: %s\n",
				strerror(errno));
			ast_ari_response_error(
				response, 500, "Internal Server Error",
				"Internal Server Error");
			break;
		}
		return;
	}

	uri_name_maxlen = strlen(args->name) * 3;
	uri_encoded_name = ast_malloc(uri_name_maxlen);
	if (!uri_encoded_name) {
		ast_ari_response_error(
			response, 500, "Internal Server Error",
			"Out of memory");
		return;
	}
	ast_uri_encode(args->name, uri_encoded_name, uri_name_maxlen,
		ast_uri_http);

	ast_asprintf(&recording_url, "/recordings/live/%s", uri_encoded_name);
	if (!recording_url) {
		ast_ari_response_error(
			response, 500, "Internal Server Error",
			"Out of memory");
		return;
	}

	json = stasis_app_recording_to_json(recording);
	if (!json) {
		ast_ari_response_error(
			response, 500, "Internal Server Error",
			"Out of memory");
		return;
	}

	ast_ari_response_created(response, recording_url, json);
}

void ast_ari_channels_get(struct ast_variable *headers,
	struct ast_ari_channels_get_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
	struct stasis_cache *cache;
	struct ast_channel_snapshot *snapshot;

	cache = ast_channel_cache();
	if (!cache) {
		ast_ari_response_error(
			response, 500, "Internal Server Error",
			"Message bus not initialized");
		return;
	}

	msg = stasis_cache_get(cache, ast_channel_snapshot_type(),
			       args->channel_id);
	if (!msg) {
		ast_ari_response_error(
			response, 404, "Not Found",
			"Channel not found");
		return;
	}

	snapshot = stasis_message_data(msg);
	ast_assert(snapshot != NULL);

	ast_ari_response_ok(response,
				ast_channel_snapshot_to_json(snapshot, NULL));
}

void ast_ari_channels_hangup(struct ast_variable *headers,
	struct ast_ari_channels_hangup_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct ast_channel *, chan, NULL, ao2_cleanup);
	int cause;

	chan = ast_channel_get_by_name(args->channel_id);
	if (chan == NULL) {
		ast_ari_response_error(
			response, 404, "Not Found",
			"Channel not found");
		return;
	}

	if (ast_strlen_zero(args->reason) || !strcmp(args->reason, "normal")) {
		cause = AST_CAUSE_NORMAL;
	} else if (!strcmp(args->reason, "busy")) {
		cause = AST_CAUSE_BUSY;
	} else if (!strcmp(args->reason, "congestion")) {
		cause = AST_CAUSE_CONGESTION;
	} else {
		ast_ari_response_error(
			response, 400, "Invalid Reason",
			"Invalid reason for hangup provided");
		return;
	}

	ast_channel_hangupcause_set(chan, cause);
	ast_softhangup(chan, AST_SOFTHANGUP_EXPLICIT);

	ast_ari_response_no_content(response);
}

void ast_ari_channels_list(struct ast_variable *headers,
	struct ast_ari_channels_list_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_cache *, cache, NULL, ao2_cleanup);
	RAII_VAR(struct ao2_container *, snapshots, NULL, ao2_cleanup);
	RAII_VAR(struct ast_json *, json, NULL, ast_json_unref);
	struct ao2_iterator i;
	void *obj;
	struct stasis_message_sanitizer *sanitize = stasis_app_get_sanitizer();

	cache = ast_channel_cache();
	if (!cache) {
		ast_ari_response_error(
			response, 500, "Internal Server Error",
			"Message bus not initialized");
		return;
	}
	ao2_ref(cache, +1);

	snapshots = stasis_cache_dump(cache, ast_channel_snapshot_type());
	if (!snapshots) {
		ast_ari_response_alloc_failed(response);
		return;
	}

	json = ast_json_array_create();
	if (!json) {
		ast_ari_response_alloc_failed(response);
		return;
	}

	i = ao2_iterator_init(snapshots, 0);
	while ((obj = ao2_iterator_next(&i))) {
		RAII_VAR(struct stasis_message *, msg, obj, ao2_cleanup);
		struct ast_channel_snapshot *snapshot = stasis_message_data(msg);
		int r;

		if (sanitize && sanitize->channel_snapshot
			&& sanitize->channel_snapshot(snapshot)) {
			continue;
		}

		r = ast_json_array_append(
			json, ast_channel_snapshot_to_json(snapshot, NULL));
		if (r != 0) {
			ast_ari_response_alloc_failed(response);
			ao2_iterator_destroy(&i);
			return;
		}
	}
	ao2_iterator_destroy(&i);

	ast_ari_response_ok(response, ast_json_ref(json));
}

static int ari_channels_set_channel_var(struct ast_channel *chan,
	const char *variable, const char *value, struct ast_ari_response *response)
{
	if (pbx_builtin_setvar_helper(chan, variable, value)) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Unable to set channel variable %s=%s", variable, value);
		return -1;
	}

	return 0;
}

static int ari_channels_set_channel_vars(struct ast_channel *chan,
	struct ast_json *variables, struct ast_ari_response *response)
{
	struct ast_json_iter *i;

	if (!variables) {
		/* nothing to do */
		return 0;
	}

	for (i = ast_json_object_iter(variables); i;
	     i = ast_json_object_iter_next(variables, i)) {
		if (ari_channels_set_channel_var(
			chan, ast_json_object_iter_key(i),
			ast_json_string_get(ast_json_object_iter_value(i)),
			response)) {
			/* response filled in by called function */
			return -1;
		}
	}

	return 0;
}

void ast_ari_channels_originate(struct ast_variable *headers,
	struct ast_ari_channels_originate_args *args,
	struct ast_ari_response *response)
{
	char *dialtech;
	char dialdevice[AST_CHANNEL_NAME];
	char *caller_id = NULL;
	char *cid_num = NULL;
	char *cid_name = NULL;
	int timeout = 30000;
	RAII_VAR(struct ast_format_cap *, cap,
		ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_NOLOCK), ast_format_cap_destroy);
	struct ast_format tmp_fmt;

	char *stuff;
	struct ast_channel *chan;
	RAII_VAR(struct ast_channel_snapshot *, snapshot, NULL, ao2_cleanup);
	struct ast_json *variable_list = NULL;

	if (!cap) {
		ast_ari_response_alloc_failed(response);
		return;
	}
	ast_format_cap_add(cap, ast_format_set(&tmp_fmt, AST_FORMAT_SLINEAR, 0));

	/* Parse any query parameters out of the body parameter */
	if (args->variables) {
		ast_ari_channels_originate_parse_body(args->variables, args);
		variable_list = ast_json_object_get(args->variables, "variables");
	}

	if (ast_strlen_zero(args->endpoint)) {
		ast_ari_response_error(response, 400, "Bad Request",
			"Endpoint must be specified");
		return;
	}

	dialtech = ast_strdupa(args->endpoint);
	if ((stuff = strchr(dialtech, '/'))) {
		*stuff++ = '\0';
		ast_copy_string(dialdevice, stuff, sizeof(dialdevice));
	}

	if (ast_strlen_zero(dialtech) || ast_strlen_zero(dialdevice)) {
		ast_ari_response_error(response, 400, "Bad Request",
			"Invalid endpoint specified");
		return;
	}

	if (args->timeout > 0) {
		timeout = args->timeout * 1000;
	} else if (args->timeout == -1) {
		timeout = -1;
	}

	if (!ast_strlen_zero(args->caller_id)) {
		caller_id = ast_strdupa(args->caller_id);
		ast_callerid_parse(caller_id, &cid_name, &cid_num);

		if (ast_is_shrinkable_phonenumber(cid_num)) {
			ast_shrink_phone_number(cid_num);
		}
	}

	if (!ast_strlen_zero(args->app)) {
		const char *app = "Stasis";

		RAII_VAR(struct ast_str *, appdata, ast_str_create(64), ast_free);

		if (!appdata) {
			ast_ari_response_alloc_failed(response);
			return;
		}

		ast_str_set(&appdata, 0, "%s", args->app);
		if (!ast_strlen_zero(args->app_args)) {
			ast_str_append(&appdata, 0, ",%s", args->app_args);
		}

		/* originate a channel, putting it into an application */
		if (ast_pbx_outgoing_app(dialtech, cap, dialdevice, timeout, app, ast_str_buffer(appdata), NULL, 0, cid_num, cid_name, NULL, NULL, &chan)) {
			ast_ari_response_alloc_failed(response);
			return;
		}
	} else if (!ast_strlen_zero(args->extension)) {
		/* originate a channel, sending it to an extension */
		if (ast_pbx_outgoing_exten(dialtech, cap, dialdevice, timeout, S_OR(args->context, "default"), args->extension, args->priority ? args->priority : 1, NULL, 0, cid_num, cid_name, NULL, NULL, &chan, 0)) {
			ast_ari_response_alloc_failed(response);
			return;
		}
	} else {
		ast_ari_response_error(response, 400, "Bad Request",
			"Application or extension must be specified");
		return;
	}

	if (ari_channels_set_channel_vars(chan, variable_list, response)) {
		/* response filled in by called function */
		return;
	}

	snapshot = ast_channel_snapshot_create(chan);
	ast_channel_unlock(chan);

	if (!ast_strlen_zero(args->app)) {
		/* channel: + channel ID + null terminator */
		char uri[9 + strlen(ast_channel_uniqueid(chan))];
		const char *uris[1] = { uri, };

		sprintf(uri, "channel:%s", ast_channel_uniqueid(chan));
		stasis_app_subscribe(args->app, uris, 1, NULL);
	}

	ast_ari_response_ok(response, ast_channel_snapshot_to_json(snapshot, NULL));
	ast_channel_unref(chan);
}

void ast_ari_channels_get_channel_var(struct ast_variable *headers,
	struct ast_ari_channels_get_channel_var_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct ast_json *, json, NULL, ast_json_unref);
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);
	RAII_VAR(char *, value, NULL, ast_free);

	ast_assert(response != NULL);

	if (ast_strlen_zero(args->variable)) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Variable name is required");
		return;
	}

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		/* response filled in by find_control */
		return;
	}

	value = stasis_app_control_get_channel_var(control, args->variable);

	if (!(json = ast_json_pack("{s: s}", "value", S_OR(value, "")))) {
		ast_ari_response_alloc_failed(response);
		return;
	}

	ast_ari_response_ok(response, ast_json_ref(json));
}

void ast_ari_channels_set_channel_var(struct ast_variable *headers,
	struct ast_ari_channels_set_channel_var_args *args,
	struct ast_ari_response *response)
{
	RAII_VAR(struct stasis_app_control *, control, NULL, ao2_cleanup);

	ast_assert(response != NULL);

	if (ast_strlen_zero(args->variable)) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Variable name is required");
		return;
	}

	control = find_control(response, args->channel_id);
	if (control == NULL) {
		/* response filled in by find_control */
		return;
	}

	if (stasis_app_control_set_channel_var(control, args->variable, args->value)) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Failed to execute function");
		return;
	}

	ast_ari_response_no_content(response);
}

void ast_ari_channels_snoop_channel(struct ast_variable *headers, struct ast_ari_channels_snoop_channel_args *args, struct ast_ari_response *response)
{
	enum stasis_app_snoop_direction spy, whisper;
	RAII_VAR(struct ast_channel *, chan, NULL, ast_channel_cleanup);
	RAII_VAR(struct ast_channel *, snoop, NULL, ast_channel_cleanup);
	RAII_VAR(struct ast_channel_snapshot *, snapshot, NULL, ao2_cleanup);

	ast_assert(response != NULL);

	if (ast_strlen_zero(args->spy) || !strcmp(args->spy, "none")) {
		spy = STASIS_SNOOP_DIRECTION_NONE;
	} else if (!strcmp(args->spy, "both")) {
		spy = STASIS_SNOOP_DIRECTION_BOTH;
	} else if (!strcmp(args->spy, "out")) {
		spy = STASIS_SNOOP_DIRECTION_OUT;
	} else if (!strcmp(args->spy, "in")) {
		spy = STASIS_SNOOP_DIRECTION_IN;
	} else {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Invalid direction specified for spy");
		return;
	}

	if (ast_strlen_zero(args->whisper) || !strcmp(args->whisper, "none")) {
		whisper = STASIS_SNOOP_DIRECTION_NONE;
	} else if (!strcmp(args->whisper, "both")) {
		whisper = STASIS_SNOOP_DIRECTION_BOTH;
	} else if (!strcmp(args->whisper, "out")) {
		whisper = STASIS_SNOOP_DIRECTION_OUT;
	} else if (!strcmp(args->whisper, "in")) {
		whisper = STASIS_SNOOP_DIRECTION_IN;
	} else {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Invalid direction specified for whisper");
		return;
	}

	if (spy == STASIS_SNOOP_DIRECTION_NONE && whisper == STASIS_SNOOP_DIRECTION_NONE) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Direction must be specified for at least spy or whisper");
		return;
	} else if (ast_strlen_zero(args->app)) {
		ast_ari_response_error(
			response, 400, "Bad Request",
			"Application name is required");
		return;
	}

	chan = ast_channel_get_by_name(args->channel_id);
	if (chan == NULL) {
		ast_ari_response_error(
			response, 404, "Channel Not Found",
			"Provided channel was not found");
		return;
	}

	snoop = stasis_app_control_snoop(chan, spy, whisper, args->app, args->app_args);
	if (snoop == NULL) {
		ast_ari_response_error(
			response, 500, "Internal error",
			"Snoop channel could not be created");
		return;
	}

	snapshot = ast_channel_snapshot_create(snoop);
	ast_ari_response_ok(response, ast_channel_snapshot_to_json(snapshot, NULL));
}