ARI recordings: Issue HTTP failures for recording requests with file conflicts

If a file already exists in the recordings directory with the same name as what
we would record, issue a 422 instead of relying on the internal failure and
issuing success.

(closes issue ASTERISK-22623)
Reported by: Joshua Colp
Review: https://reviewboard.asterisk.org/r/2922/
........

Merged revisions 401973 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@401999 65c4cc65-6c06-0410-ace0-fbb531ad65f3

res/ari/ari_model_validators.h

@@ -862,6 +862,60 @@ int ast_ari_validate_playback_started(struct ast_json *json);
  */
 ari_validator ast_ari_validate_playback_started_fn(void);
 
+/*!
+ * \brief Validator for RecordingFailed.
+ *
+ * Event showing failure of a recording operation.
+ *
+ * \param json JSON object to validate.
+ * \returns True (non-zero) if valid.
+ * \returns False (zero) if invalid.
+ */
+int ast_ari_validate_recording_failed(struct ast_json *json);
+
+/*!
+ * \brief Function pointer to ast_ari_validate_recording_failed().
+ *
+ * See \ref ast_ari_model_validators.h for more details.
+ */
+ari_validator ast_ari_validate_recording_failed_fn(void);
+
+/*!
+ * \brief Validator for RecordingFinished.
+ *
+ * Event showing the completion of a recording operation.
+ *
+ * \param json JSON object to validate.
+ * \returns True (non-zero) if valid.
+ * \returns False (zero) if invalid.
+ */
+int ast_ari_validate_recording_finished(struct ast_json *json);
+
+/*!
+ * \brief Function pointer to ast_ari_validate_recording_finished().
+ *
+ * See \ref ast_ari_model_validators.h for more details.
+ */
+ari_validator ast_ari_validate_recording_finished_fn(void);
+
+/*!
+ * \brief Validator for RecordingStarted.
+ *
+ * Event showing the start of a recording operation.
+ *
+ * \param json JSON object to validate.
+ * \returns True (non-zero) if valid.
+ * \returns False (zero) if invalid.
+ */
+int ast_ari_validate_recording_started(struct ast_json *json);
+
+/*!
+ * \brief Function pointer to ast_ari_validate_recording_started().
+ *
+ * See \ref ast_ari_model_validators.h for more details.
+ */
+ari_validator ast_ari_validate_recording_started_fn(void);
+
 /*!
  * \brief Validator for StasisEnd.
  *
@@ -1112,6 +1166,13 @@ ari_validator ast_ari_validate_application_fn(void);
  * - application: string (required)
  * - timestamp: Date
  * - playback: Playback (required)
+ * RecordingFailed
+ * - cause: string (required)
+ * - recording: LiveRecording (required)
+ * RecordingFinished
+ * - recording: LiveRecording (required)
+ * RecordingStarted
+ * - recording: LiveRecording (required)
  * StasisEnd
  * - type: string (required)
  * - application: string (required)