Add HTTP and HTTPS support to the simple exporting connector (#9911)

27 files changed, 801 insertions, 363 deletions

diff --git a/exporting/README.md b/exporting/README.md
index 1a04e4085d..8f490cc2ff 100644
--- a/exporting/README.md
+++ b/exporting/README.md
@@ -44,7 +44,7 @@ X seconds (though, it can send them per second if you need it to).
         also be configured). Learn more in our guide to [export and visualize Netdata metrics in
         Graphite](/docs/guides/export/export-netdata-metrics-graphite.md).
     -   [**JSON** document databases](/exporting/json/README.md)
-    -   [**OpenTSDB**](/exporting/opentsdb/README.md): Use a plaintext, HTTP, or HTTPS interfaces. Metrics are sent to
+    -   [**OpenTSDB**](/exporting/opentsdb/README.md): Use a plaintext or HTTP interfaces. Metrics are sent to
         OpenTSDB as `prefix.chart.dimension` with tag `host=hostname`.
     -   [**MongoDB**](/exporting/mongodb/README.md): Metrics are sent to the database in `JSON` format.
     -   [**Prometheus**](/exporting/prometheus/README.md): Use an existing Prometheus installation to scrape metrics
@@ -173,8 +173,10 @@ You can configure each connector individually using the available [options](#opt
 -   `[prometheus:exporter]` defines settings for Prometheus exporter API queries (e.g.:
     `http://NODE:19999/api/v1/allmetrics?format=prometheus&help=yes&source=as-collected`).
 -   `[<type>:<name>]` keeps settings for a particular exporting connector instance, where:
-  -   `type` selects the exporting connector type: graphite | opentsdb:telnet | opentsdb:http | opentsdb:https |
-      prometheus_remote_write | json | kinesis | pubsub | mongodb
+  -   `type` selects the exporting connector type: graphite | opentsdb:telnet | opentsdb:http |
+      prometheus_remote_write | json | kinesis | pubsub | mongodb. For graphite, opentsdb,
+      json, and prometheus_remote_write connectors you can also use `:http` or `:https` modifiers
+      (e.g.: `opentsdb:https`).
   -   `name` can be arbitrary instance name you chose.
 
 ### Options
@@ -270,6 +272,13 @@ Configure individual connectors and override any global settings with the follow
 > You can check how the host tags were parsed using the /api/v1/info API call. But, keep in mind that backends subsystem
 > is deprecated and will be deleted soon. Please move your existing tags to the `[host labels]` section.
 
+## HTTPS
+
+Netdata can send metrics to external databases using the TLS/SSL protocol. Unfortunately, some of
+them does not support encrypted connections, so you will have to configure a reverse proxy to enable
+HTTPS communication between Netdata and an external database. You can set up a reverse proxy with
+[Nginx](/docs/Running-behind-nginx.md).
+
 ## Exporting engine monitoring
 
 Netdata creates five charts in the dashboard, under the **Netdata Monitoring** section, to help you monitor the health
diff --git a/exporting/aws_kinesis/aws_kinesis.c b/exporting/aws_kinesis/aws_kinesis.c
index 00600fa9bb..036afb49fc 100644
--- a/exporting/aws_kinesis/aws_kinesis.c
+++ b/exporting/aws_kinesis/aws_kinesis.c
@@ -48,7 +48,7 @@ int init_aws_kinesis_instance(struct instance *instance)
     instance->end_host_formatting = flush_host_labels;
     instance->end_batch_formatting = NULL;
 
-    instance->send_header = NULL;
+    instance->prepare_header = NULL;
     instance->check_response = NULL;
 
     instance->buffer = (void *)buffer_create(0);
diff --git a/exporting/clean_connectors.c b/exporting/clean_connectors.c
index 4ad644d69c..459777f0fd 100644
--- a/exporting/clean_connectors.c
+++ b/exporting/clean_connectors.c
@@ -35,3 +35,46 @@ void clean_instance(struct instance *instance)
     uv_cond_destroy(&instance->cond_var);
     // uv_mutex_destroy(&instance->mutex);
 }
+
+/**
+ * Clean up a simple connector instance on Netdata exit
+ *
+ * @param instance an instance data structure.
+ */
+void simple_connector_cleanup(struct instance *instance)
+{
+    info("EXPORTING: cleaning up instance %s ...", instance->config.name);
+
+    struct simple_connector_data *simple_connector_data =
+        (struct simple_connector_data *)instance->connector_specific_data;
+
+    buffer_free(instance->buffer);
+    buffer_free(simple_connector_data->buffer);
+    buffer_free(simple_connector_data->header);
+
+    struct simple_connector_buffer *next_buffer = simple_connector_data->first_buffer;
+    for (int i = 0; i < instance->config.buffer_on_failures; i++) {
+        struct simple_connector_buffer *current_buffer = next_buffer;
+        next_buffer = next_buffer->next;
+
+        buffer_free(current_buffer->header);
+        buffer_free(current_buffer->buffer);
+        freez(current_buffer);
+    }
+
+#ifdef ENABLE_HTTPS
+    if (simple_connector_data->conn)
+        SSL_free(simple_connector_data->conn);
+#endif
+
+    freez(simple_connector_data);
+
+    struct simple_connector_config *simple_connector_config =
+        (struct simple_connector_config *)instance->config.connector_specific_config;
+    freez(simple_connector_config);
+
+    info("EXPORTING: instance %s exited", instance->config.name);
+    instance->exited = 1;
+
+    return;
+}
diff --git a/exporting/exporting_engine.h b/exporting/exporting_engine.h
index b436f5d809..e0993c98f8 100644
--- a/exporting/exporting_engine.h
+++ b/exporting/exporting_engine.h
@@ -46,10 +46,12 @@ typedef enum exporting_options {
 typedef enum exporting_connector_types {
     EXPORTING_CONNECTOR_TYPE_UNKNOWN,                 // Invalid type
     EXPORTING_CONNECTOR_TYPE_GRAPHITE,                // Send plain text to Graphite
-    EXPORTING_CONNECTOR_TYPE_OPENTSDB_USING_TELNET,   // Send data to OpenTSDB using telnet API
-    EXPORTING_CONNECTOR_TYPE_OPENTSDB_USING_HTTP,     // Send data to OpenTSDB using HTTP API
-    EXPORTING_CONNECTOR_TYPE_JSON,                    // Stores the data using JSON.
-    EXPORTING_CONNECTOR_TYPE_PROMETHEUS_REMOTE_WRITE, // The user selected to use Prometheus backend
+    EXPORTING_CONNECTOR_TYPE_GRAPHITE_HTTP,           // Send data to Graphite using HTTP API
+    EXPORTING_CONNECTOR_TYPE_JSON,                    // Send data in JSON format
+    EXPORTING_CONNECTOR_TYPE_JSON_HTTP,               // Send data in JSON format using HTTP API
+    EXPORTING_CONNECTOR_TYPE_OPENTSDB,                // Send data to OpenTSDB using telnet API
+    EXPORTING_CONNECTOR_TYPE_OPENTSDB_HTTP,           // Send data to OpenTSDB using HTTP API
+    EXPORTING_CONNECTOR_TYPE_PROMETHEUS_REMOTE_WRITE, // User selected to use Prometheus backend
     EXPORTING_CONNECTOR_TYPE_KINESIS,                 // Send message to AWS Kinesis
     EXPORTING_CONNECTOR_TYPE_PUBSUB,                  // Send message to Google Cloud Pub/Sub
     EXPORTING_CONNECTOR_TYPE_MONGODB,                 // Send data to MongoDB collection
@@ -81,6 +83,38 @@ struct simple_connector_config {
     int default_port;
 };
 
+struct simple_connector_buffer {
+    BUFFER *header;
+    BUFFER *buffer;
+
+    size_t buffered_metrics;
+    size_t buffered_bytes;
+
+    int used;
+
+    struct simple_connector_buffer *next;
+};
+
+struct simple_connector_data {
+    void *connector_specific_data;
+
+    size_t total_buffered_metrics;
+
+    BUFFER *header;
+    BUFFER *buffer;
+    size_t buffered_metrics;
+    size_t buffered_bytes;
+
+    struct simple_connector_buffer *previous_buffer;
+    struct simple_connector_buffer *first_buffer;
+    struct simple_connector_buffer *last_buffer;
+
+#ifdef ENABLE_HTTPS
+    SSL *conn; //SSL connection
+    int flags; //The flags for SSL connection
+#endif
+};
+
 struct prometheus_remote_write_specific_config {
     char *remote_write_path;
 };
@@ -175,7 +209,7 @@ 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);
+    void (*prepare_header)(struct instance *instance);
     int (*check_response)(BUFFER *buffer, struct instance *instance);
 
     void *connector_specific_data;
@@ -210,6 +244,7 @@ struct engine *read_exporting_config();
 EXPORTING_CONNECTOR_TYPE exporting_select_type(const char *type);
 
 int init_connectors(struct engine *engine);
+void simple_connector_init(struct instance *instance);
 
 int mark_scheduled_instances(struct engine *engine);
 void prepare_buffers(struct engine *engine);
@@ -232,11 +267,12 @@ void end_chart_formatting(struct engine *engine, RRDSET *st);
 void end_host_formatting(struct engine *engine, RRDHOST *host);
 void end_batch_formatting(struct engine *engine);
 int flush_host_labels(struct instance *instance, RRDHOST *host);
-int simple_connector_update_buffered_bytes(struct instance *instance);
+int simple_connector_end_batch(struct instance *instance);
 
 int exporting_discard_response(BUFFER *buffer, struct instance *instance);
 void simple_connector_receive_response(int *sock, struct instance *instance);
-void simple_connector_send_buffer(int *sock, int *failures, struct instance *instance);
+void simple_connector_send_buffer(
+    int *sock, int *failures, struct instance *instance, BUFFER *header, BUFFER *buffer, size_t buffered_metrics);
 void simple_connector_worker(void *instance_p);
 
 void create_main_rusage_chart(RRDSET **st_rusage, RRDDIM **rd_user, RRDDIM **rd_system);
@@ -244,6 +280,7 @@ void send_main_rusage(RRDSET *st_rusage, RRDDIM *rd_user, RRDDIM *rd_system);
 void send_internal_metrics(struct instance *instance);
 
 extern void clean_instance(struct instance *ptr);
+void simple_connector_cleanup(struct instance *instance);
 
 static inline void disable_instance(struct instance *instance)
 {
diff --git a/exporting/graphite/README.md b/exporting/graphite/README.md
index 95b8ef954d..2ac7adc7af 100644
--- a/exporting/graphite/README.md
+++ b/exporting/graphite/README.md
@@ -3,6 +3,7 @@ title: "Export metrics to Graphite providers"
 sidebar_label: Graphite
 description: "Archive your Agent's metrics to a any Graphite database provider for long-term storage, further analysis, or correlation with data from other sources."
 custom_edit_url: https://github.com/netdata/netdata/edit/master/exporting/graphite/README.md
+sidebar_label: Graphite
 -->
 
 # Export metrics to Graphite providers
@@ -21,6 +22,9 @@ directory and set the following options:
     destination = localhost:2003
 ```
 
+Add `:http` or `:https` modifiers to the connector type if you need to use other than a plaintext protocol. For example: `graphite:http:my_graphite_instance`,
+`graphite:https:my_graphite_instance`.
+
 The Graphite connector is further configurable using additional settings. See the [exporting reference
 doc](/exporting/README.md#options) for details.
 
diff --git a/exporting/graphite/graphite.c b/exporting/graphite/graphite.c
index 6aad2054db..23e40c369e 100644
--- a/exporting/graphite/graphite.c
+++ b/exporting/graphite/graphite.c
@@ -16,6 +16,17 @@ int init_graphite_instance(struct instance *instance)
     instance->config.connector_specific_config = (void *)connector_specific_config;
     connector_specific_config->default_port = 2003;
 
+    struct simple_connector_data *connector_specific_data = callocz(1, sizeof(struct simple_connector_data));
+    instance->connector_specific_data = connector_specific_data;
+
+#ifdef ENABLE_HTTPS
+    connector_specific_data->flags = NETDATA_SSL_START;
+    connector_specific_data->conn = NULL;
+    if (instance->config.options & EXPORTING_OPTION_USE_TLS) {
+        security_start_ssl(NETDATA_SSL_CONTEXT_EXPORTING);
+    }
+#endif
+
     instance->start_batch_formatting = NULL;
     instance->start_host_formatting = format_host_labels_graphite_plaintext;
     instance->start_chart_formatting = NULL;
@@ -27,9 +38,13 @@ int init_graphite_instance(struct instance *instance)
 
     instance->end_chart_formatting = NULL;
     instance->end_host_formatting = flush_host_labels;
-    instance->end_batch_formatting = simple_connector_update_buffered_bytes;
+    instance->end_batch_formatting = simple_connector_end_batch;
+
+    if (instance->config.type == EXPORTING_CONNECTOR_TYPE_GRAPHITE_HTTP)
+        instance->prepare_header = graphite_http_prepare_header;
+    else
+        instance->prepare_header = NULL;
 
-    instance->send_header = NULL;
     instance->check_response = exporting_discard_response;
 
     instance->buffer = (void *)buffer_create(0);
@@ -37,6 +52,9 @@ int init_graphite_instance(struct instance *instance)
         error("EXPORTING: cannot create buffer for graphite exporting connector instance %s", instance->config.name);
         return 1;
     }
+
+    simple_connector_init(instance);
+
     if (uv_mutex_init(&instance->mutex))
         return 1;
     if (uv_cond_init(&instance->cond_var))
@@ -187,3 +205,26 @@ int format_dimension_stored_graphite_plaintext(struct instance *instance, RRDDIM
 
     return 0;
 }
+
+/**
+ * Ppepare HTTP header
+ *
+ * @param instance an instance data structure.
+ * @return Returns 0 on success, 1 on failure.
+ */
+void graphite_http_prepare_header(struct instance *instance)
+{
+    struct simple_connector_data *simple_connector_data = instance->connector_specific_data;
+
+    buffer_sprintf(
+        simple_connector_data->last_buffer->header,
+        "POST /api/put HTTP/1.1\r\n"
+        "Host: %s\r\n"
+        "Content-Type: application/graphite\r\n"
+        "Content-Length: %lu\r\n"
+        "\r\n",
+        instance->config.destination,
+        buffer_strlen(simple_connector_data->last_buffer->buffer));
+
+    return;
+}
diff --git a/exporting/graphite/graphite.h b/exporting/graphite/graphite.h
index edda498e85..993c12e57a 100644
--- a/exporting/graphite/graphite.h
+++ b/exporting/graphite/graphite.h
@@ -13,4 +13,6 @@ int format_host_labels_graphite_plaintext(struct instance *instance, RRDHOST *ho
 int format_dimension_collected_graphite_plaintext(struct instance *instance, RRDDIM *rd);
 int format_dimension_stored_graphite_plaintext(struct instance *instance, RRDDIM *rd);
 
+void graphite_http_prepare_header(struct instance *instance);
+
 #endif //NETDATA_EXPORTING_GRAPHITE_H
diff --git a/exporting/init_connectors.c b/exporting/init_connectors.c
index 4a68118970..57ac030d9a 100644
--- a/exporting/init_connectors.c
+++ b/exporting/init_connectors.c
@@ -40,15 +40,23 @@ int init_connectors(struct engine *engine)
                 if (init_graphite_instance(instance) != 0)
                     return 1;
                 break;
+            case EXPORTING_CONNECTOR_TYPE_GRAPHITE_HTTP:
+                if (init_graphite_instance(instance) != 0)
+                    return 1;
+                break;
             case EXPORTING_CONNECTOR_TYPE_JSON:
                 if (init_json_instance(instance) != 0)
                     return 1;
                 break;
-            case EXPORTING_CONNECTOR_TYPE_OPENTSDB_USING_TELNET:
+            case EXPORTING_CONNECTOR_TYPE_JSON_HTTP:
+                if (init_json_http_instance(instance) != 0)
+                    return 1;
+                break;
+            case EXPORTING_CONNECTOR_TYPE_OPENTSDB:
                 if (init_opentsdb_telnet_instance(instance) != 0)
                     return 1;
                 break;
-            case EXPORTING_CONNECTOR_TYPE_OPENTSDB_USING_HTTP:
+            case EXPORTING_CONNECTOR_TYPE_OPENTSDB_HTTP:
                 if (init_opentsdb_http_instance(instance) != 0)
                     return 1;
                 break;
@@ -96,3 +104,36 @@ int init_connectors(struct engine *engine)
 
     return 0;
 }
+
+/**
+ * Initialize a ring buffer for a simple connector
+ *
+ * @param instance an instance data structure.
+ */
+void simple_connector_init(struct instance *instance)
+{
+    struct simple_connector_data *connector_specific_data =
+        (struct simple_connector_data *)instance->connector_specific_data;
+
+    // create a ring buffer
+    struct simple_connector_buffer *first_buffer = NULL;
+
+    if (instance->config.buffer_on_failures < 1)
+        instance->config.buffer_on_failures = 1;
+
+    for (int i = 0; i < instance->config.buffer_on_failures; i++) {
+        struct simple_connector_buffer *current_buffer = callocz(1, sizeof(struct simple_connector_buffer));
+
+        if (!connector_specific_data->first_buffer)
+            first_buffer = current_buffer;
+        else
+            current_buffer->next = connector_specific_data->first_buffer;
+
+        connector_specific_data->first_buffer = current_buffer;
+    }
+
+    first_buffer->next = connector_specific_data->first_buffer;
+    connector_specific_data->last_buffer = connector_specific_data->first_buffer;
+
+    return;
+}
diff --git a/exporting/json/README.md b/exporting/json/README.md
index 8ef084cf22..1dd41e738e 100644
--- a/exporting/json/README.md
+++ b/exporting/json/README.md
@@ -3,6 +3,7 @@ title: "Export metrics to JSON document databases"
 sidebar_label: JSON
 description: "Archive your Agent's metrics to a JSON document database for long-term storage, further analysis, or correlation with data from other sources."
 custom_edit_url: https://github.com/netdata/netdata/edit/master/exporting/json/README.md
+sidebar_label: JSON Document Databases
 -->
 
 # Export metrics to JSON document databases
@@ -21,6 +22,9 @@ directory and set the following options:
     destination = localhost:5448
 ```
 
+Add `:http` or `:https` modifiers to the connector type if you need to use other than a plaintext protocol. For example: `json:http:my_json_instance`,
+`json:https:my_json_instance`.
+
 The JSON connector is further configurable using additional settings. See the [exporting reference
 doc](/exporting/README.md#options) for details.
 
diff --git a/exporting/json/json.c b/exporting/json/json.c
index cea7eff07c..458e7e8cce 100644
--- a/exporting/json/json.c
+++ b/exporting/json/json.c
@@ -16,6 +16,9 @@ int init_json_instance(struct instance *instance)
     instance->config.connector_specific_config = (void *)connector_specific_config;
     connector_specific_config->default_port = 5448;
 
+    struct simple_connector_data *connector_specific_data = callocz(1, sizeof(struct simple_connector_data));
+    instance->connector_specific_data = connector_specific_data;
+
     instance->start_batch_formatting = NULL;
     instance->start_host_formatting = format_host_labels_json_plaintext;
     instance->start_chart_formatting = NULL;
@@ -27,9 +30,10 @@ int init_json_instance(struct instance *instance)
 
     instance->end_chart_formatting = NULL;
     instance->end_host_formatting = flush_host_labels;
-    instance->end_batch_formatting = simple_connector_update_buffered_bytes;
+    instance->end_batch_formatting = simple_connector_end_batch;
+
+    instance->prepare_header = NULL;
 
-    instance->send_header = NULL;
     instance->check_response = exporting_discard_response;
 
     instance->buffer = (void *)buffer_create(0);
@@ -37,6 +41,63 @@ int init_json_instance(struct instance *instance)
         error("EXPORTING: cannot create buffer for json exporting connector instance %s", instance->config.name);
         return 1;
     }
+
+    simple_connector_init(instance);
+
+    if (uv_mutex_init(&instance->mutex))
+        return 1;
+    if (uv_cond_init(&instance->cond_var))
+        return 1;
+
+    return 0;
+}
+
+/**
+ * Initialize JSON connector instance for HTTP protocol
+ *
+ * @param instance an instance data structure.
+ * @return Returns 0 on success, 1 on failure.
+ */
+int init_json_http_instance(struct instance *instance)
+{
+    instance->worker = simple_connector_worker;
+
+    struct simple_connector_config *connector_specific_config = callocz(1, sizeof(struct simple_connector_config));
+    instance->config.connector_specific_config = (void *)connector_specific_config;
+    connector_specific_config->default_port = 5448;
+
+    struct simple_connector_data *connector_specific_data = callocz(1, sizeof(struct simple_connector_data));
+    instance->connector_specific_data = connector_specific_data;
+
+#ifdef ENABLE_HTTPS
+    connector_specific_data->flags = NETDATA_SSL_START;
+    connector_specific_data->conn = NULL;
+    if (instance->config.options & EXPORTING_OPTION_USE_TLS) {
+        security_start_ssl(NETDATA_SSL_CONTEXT_EXPORTING);
+    }
+#endif
+
+    instance->start_batch_formatting = open_batch_json_http;
+    instance->start_host_formatting = format_host_labels_json_plaintext;
+    instance->start_chart_formatting = NULL;
+
+    if (EXPORTING_OPTIONS_DATA_SOURCE(instance->config.options) == EXPORTING_SOURCE_DATA_AS_COLLECTED)
+        instance->metric_formatting = format_dimension_collected_json_plaintext;
+    else
+        instance->metric_formatting = format_dimension_stored_json_plaintext;
+
+    instance->end_chart_formatting = NULL;
+    instance->end_host_formatting = flush_host_labels;
+    instance->end_batch_formatting = close_batch_json_http;
+
+    instance->prepare_header = json_http_prepare_header;
+
+    instance->check_response = exporting_discard_response;
+
+    instance->buffer = (void *)buffer_create(0);
+
+    simple_connector_init(instance);
+
     if (uv_mutex_init(&instance->mutex))
         return 1;
     if (uv_cond_init(&instance->cond_var))
@@ -111,6 +172,11 @@ int format_dimension_collected_json_plaintext(struct instance *instance, RRDDIM
         }
     }
 
+    if (instance->config.type == EXPORTING_CONNECTOR_TYPE_JSON_HTTP) {
+        if (buffer_strlen((BUFFER *)instance->buffer) > 2)
+        buffer_strcat(instance->buffer, ",\n");
+    }
+
     buffer_sprintf(
         instance->buffer,
 
@@ -131,7 +197,7 @@ int format_dimension_collected_json_plaintext(struct instance *instance, RRDDIM
         "\"name\":\"%s\","
         "\"value\":" COLLECTED_NUMBER_FORMAT ","
 
-        "\"timestamp\":%llu}\n",
+        "\"timestamp\":%llu}",
 
         instance->config.prefix,
         (host == localhost) ? engine->config.hostname : host->hostname,
@@ -153,6 +219,10 @@ int format_dimension_collected_json_plaintext(struct instance *instance, RRDDIM
 
         (unsigned long long)rd->last_collected_time.tv_sec);
 
+    if (instance->config.type != EXPORTING_CONNECTOR_TYPE_JSON_HTTP) {
+        buffer_strcat(instance->buffer, "\n");
+    }
+
     return 0;
 }
 
@@ -189,6 +259,11 @@ int format_dimension_stored_json_plaintext(struct instance *instance, RRDDIM *rd
         }
     }
 
+    if (instance->config.type == EXPORTING_CONNECTOR_TYPE_JSON_HTTP) {
+        if (buffer_strlen((BUFFER *)instance->buffer) > 2)
+            buffer_strcat(instance->buffer, ",\n");
+    }
+
     buffer_sprintf(
         instance->buffer,
         "{"
@@ -208,7 +283,7 @@ int format_dimension_stored_json_plaintext(struct instance *instance, RRDDIM *rd
         "\"name\":\"%s\","
         "\"value\":" CALCULATED_NUMBER_FORMAT ","
 
-        "\"timestamp\": %llu}\n",
+        "\"timestamp\": %llu}",
 
         instance->config.prefix,
         (host == localhost) ? engine->config.hostname : host->hostname,
@@ -230,5 +305,60 @@ int format_dimension_stored_json_plaintext(struct instance *instance, RRDDIM *rd
 
         (unsigned long long)last_t);
 
+    if (instance->config.type != EXPORTING_CONNECTOR_TYPE_JSON_HTTP) {
+        buffer_strcat(instance->buffer, "\n");
+    }
+
     return 0;
 }
+
+/**
+ * Open a JSON list for a bach
+ *
+ * @param instance an instance data structure.
+ * @return Always returns 0.
+ */
+int open_batch_json_http(struct instance *instance)
+{
+    buffer_strcat(instance->buffer, "[\n");
+
+    return 0;
+}
+
+/**
+ * Close a JSON list for a bach and update buffered bytes counter
+ *
+ * @param instance an instance data structure.
+ * @return Always returns 0.
+ */
+int close_batch_json_http(struct instance *instance)
+{
+    buffer_strcat(instance->buffer, "\n]\n");
+
+    simple_connector_end_batch(instance);
+
+    return 0;
+}
+
+/**
+ * Prepare HTTP header
+ *
+ * @param instance an instance data structure.
+ * @return Returns 0 on success, 1 on failure.
+ */
+void json_http_prepare_header(struct instance *instance)
+{
+    struct simple_connector_data *simple_connector_data = instance->connector_specific_data;
+
+    buffer_sprintf(
+        simple_connector_data->last_buffer->header,
+        "POST /api/put HTTP/1.1\r\n"
+        "Host: %s\r\n"
+        "Content-Type: application/json\r\n"
+        "Content-Length: %lu\r\n"
+        "\r\n",
+        instance->config.destination,
+        buffer_strlen(simple_connector_data->last_buffer->buffer));
+
+    return;
+}
diff --git a/exporting/json/json.h b/exporting/json/json.h
index f4d3756631..d916263a9b 100644
--- a/exporting/json/json.h
+++ b/exporting/json/json.h
@@ -6,10 +6,16 @@
 #include "exporting/exporting_engine.h"
 
 int init_json_instance(struct instance *instance);
+int init_json_http_instance(struct instance *instance);
 
 int format_host_labels_json_plaintext(struct instance *instance, RRDHOST *host);
 
 int format_dimension_collected_json_plaintext(struct instance *instance, RRDDIM *rd);
 int format_dimension_stored_json_plaintext(struct instance *instance, RRDDIM *rd);
 
+int open_batch_json_http(struct instance *instance);
+int close_batch_json_http(struct instance *instance);
+
+void json_http_prepare_header(struct instance *instance);
+
 #endif //NETDATA_EXPORTING_JSON_H
diff --git a/exporting/mongodb/mongodb.c b/exporting/mongodb/mongodb.c
index c2cb72f9e3..44922a2424 100644
--- a/exporting/mongodb/mongodb.c
+++ b/exporting/mongodb/mongodb.c
@@ -102,7 +102,7 @@ int init_mongodb_instance(struct instance *instance)
     instance->end_host_formatting = flush_host_labels;
     instance->end_batch_formatting = format_batch_mongodb;
 
-    instance->send_header = NULL;
+    instance->prepare_header = NULL;
     instance->check_response = NULL;
 
     instance->buffer = (void *)buffer_create(0);
@@ -284,9 +284,12 @@ void mongodb_connector_worker(void *instance_p)
         struct stats *stats = &instance->stats;
 
         uv_mutex_lock(&instance->mutex);
-        while (!instance->data_is_ready)
-            uv_cond_wait(&instance->cond_var, &instance->mutex);
-        instance->data_is_ready = 0;
+        if (!connector_specific_data->first_buffer->insert ||
+            !connector_specific_data->first_buffer->documents_inserted) {
+            while (!instance->data_is_ready)
+                uv_cond_wait(&instance->cond_var, &instance->mutex);
+            instance->data_is_ready = 0;
+        }
 
         if (unlikely(instance->engine->exit)) {
             uv_mutex_unlock(&instance->mutex);
diff --git a/exporting/mongodb/mongodb.h b/exporting/mongodb/mongodb.h
index 5116e66fab..f1867b2888 100644
--- a/exporting/mongodb/mongodb.h
+++ b/exporting/mongodb/mongodb.h
@@ -21,7 +21,6 @@ struct mongodb_specific_data {
 
     size_t total_documents_inserted;
 
-    bson_t **current_insert;
     struct bson_buffer *first_buffer;
     struct bson_buffer *last_buffer;
 };
diff --git a/exporting/opentsdb/README.md b/exporting/opentsdb/README.md
index 6b5f198b0b..3765ad2712 100644
--- a/exporting/opentsdb/README.md
+++ b/exporting/opentsdb/README.md
@@ -1,40 +1,30 @@
 <!--
-title: "Export metrics to OpenTSDB with HTTP"
-description: "Archive your Agent's metrics to a OpenTSDB database for long-term storage and further analysis."
+title: