Add a Prometheus Remote Write connector to the exporting engine (#8292)

* Copy files from the Prometheus remote write backend

* Update the documentation

* Rename backend -> exporting

* Add the connector to the Netdata build

* Separate files for the remote write connector

* Add an initializer and formatters

* Read a connector specific configuration option

* Add a separate function for header sending

* Use labels instead of tags

* Separate write request for every instance

* Add unit tests

1 files changed, 9 insertions, 35 deletions

diff --git a/exporting/exporting_engine.h b/exporting/exporting_engine.h
index c1e63a42eb..6a8296a19b 100644
--- a/exporting/exporting_engine.h
+++ b/exporting/exporting_engine.h
@@ -13,41 +13,8 @@
 
 extern struct config exporting_config;
 
-#define EXPORTER_DATA_SOURCE                    "data source"
-#define EXPORTER_DATA_SOURCE_DEFAULT            "average"
-
-#define EXPORTER_DESTINATION                    "destination"
-#define EXPORTER_DESTINATION_DEFAULT            "localhost"
-
-#define EXPORTER_UPDATE_EVERY                   "update every"
-#define EXPORTER_UPDATE_EVERY_DEFAULT           10
-
-#define EXPORTER_BUF_ONFAIL                     "buffer on failures"
-#define EXPORTER_BUF_ONFAIL_DEFAULT             10
-
-#define EXPORTER_TIMEOUT_MS                     "timeout ms"
-#define EXPORTER_TIMEOUT_MS_DEFAULT             10000
-
-#define EXPORTER_SEND_CHART_MATCH               "send charts matching"
-#define EXPORTER_SEND_CHART_MATCH_DEFAULT       "*"
-
-#define EXPORTER_SEND_HOST_MATCH                "send hosts matching"
-#define EXPORTER_SEND_HOST_MATCH_DEFAULT        "localhost *"
-
-#define EXPORTER_SEND_CONFIGURED_LABELS         "send configured labels"
-#define EXPORTER_SEND_CONFIGURED_LABELS_DEFAULT CONFIG_BOOLEAN_YES
-
-#define EXPORTER_SEND_AUTOMATIC_LABELS          "send automatic labels"
-#define EXPORTER_SEND_AUTOMATIC_LABELS_DEFAULT  CONFIG_BOOLEAN_NO
-
-#define EXPORTER_SEND_NAMES                     "send names instead of ids"
-#define EXPORTER_SEND_NAMES_DEFAULT             CONFIG_BOOLEAN_YES
-
-#define EXPORTER_KINESIS_STREAM_NAME            "stream name"
-#define EXPORTER_KINESIS_STREAM_NAME_DEFAULT    "netdata"
-
-#define EXPORTER_AWS_ACCESS_KEY_ID              "aws_access_key_id"
-#define EXPORTER_AWS_SECRET_ACCESS_KEY          "aws_secret_access_key"
+#define EXPORTING_UPDATE_EVERY_OPTION_NAME "update every"
+#define EXPORTING_UPDATE_EVERY_DEFAULT     10
 
 typedef enum exporting_options {
     EXPORTING_OPTION_NONE                   = 0,
@@ -98,6 +65,10 @@ struct simple_connector_config {
     int default_port;
 };
 
+struct prometheus_remote_write_specific_config {
+    char *remote_write_path;
+};
+
 struct aws_kinesis_specific_config {
     char *stream_name;
     char *auth_key_id;
@@ -152,6 +123,9 @@ struct instance {
     int (*end_host_formatting)(struct instance *instance, RRDHOST *host);
     int (*end_batch_formatting)(struct instance *instance);
 
+    int (*send_header)(int *sock, struct instance *instance);
+    int (*check_response)(BUFFER *buffer, struct instance *instance);
+
     void *connector_specific_data;
 
     size_t index;