modularized all source code (#4391)

* modularized all external plugins

* added README.md in plugins

* fixed title

* fixed typo

* relative link to external plugins

* external plugins configuration README

* added plugins link

* remove plugins link

* plugin names are links

* added links to external plugins

* removed unecessary spacing

* list to table

* added language

* fixed typo

* list to table on internal plugins

* added more documentation to internal plugins

* moved python, node, and bash code and configs into the external plugins

* added statsd README

* fix bug with corrupting config.h every 2nd compilation

* moved all config files together with their code

* more documentation

* diskspace info

* fixed broken links in apps.plugin

* added backends docs

* updated plugins readme

* move nc-backend.sh to backends

* created daemon directory

* moved all code outside src/

* fixed readme identation

* renamed plugins.d.plugin to plugins.d

* updated readme

* removed linux- from linux plugins

* updated readme

* updated readme

* updated readme

* updated readme

* updated readme

* updated readme

* fixed README.md links

* fixed netdata tree links

* updated codacy, codeclimate and lgtm excluded paths

* update CMakeLists.txt

* updated automake options at top directory

* libnetdata slit into directories

* updated READMEs

* updated READMEs

* updated ARL docs

* updated ARL docs

* moved /plugins to /collectors

* moved all external plugins outside plugins.d

* updated codacy, codeclimate, lgtm

* updated README

* updated url

* updated readme

* updated readme

* updated readme

* updated readme

* moved api and web into webserver

* web/api web/gui web/server

* modularized webserver

* removed web/gui/version.txt

3 files changed, 129 insertions, 0 deletions

diff --git a/backends/graphite/Makefile.am b/backends/graphite/Makefile.am
new file mode 100644
index 0000000000..babdcf0df3
--- /dev/null
+++ b/backends/graphite/Makefile.am
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+AUTOMAKE_OPTIONS = subdir-objects
+MAINTAINERCLEANFILES = $(srcdir)/Makefile.in
diff --git a/backends/graphite/graphite.c b/backends/graphite/graphite.c
new file mode 100644
index 0000000000..805703893b
--- /dev/null
+++ b/backends/graphite/graphite.c
@@ -0,0 +1,90 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#define BACKENDS_INTERNALS
+#include "graphite.h"
+
+// ----------------------------------------------------------------------------
+// graphite backend
+
+int format_dimension_collected_graphite_plaintext(
+        BUFFER *b                 // the buffer to write data to
+        , const char *prefix        // the prefix to use
+        , RRDHOST *host             // the host this chart comes from
+        , const char *hostname      // the hostname (to override host->hostname)
+        , RRDSET *st                // the chart
+        , RRDDIM *rd                // the dimension
+        , time_t after              // the start timestamp
+        , time_t before             // the end timestamp
+        , BACKEND_OPTIONS backend_options // BACKEND_SOURCE_* bitmap
+) {
+    (void)host;
+    (void)after;
+    (void)before;
+
+    char chart_name[RRD_ID_LENGTH_MAX + 1];
+    char dimension_name[RRD_ID_LENGTH_MAX + 1];
+    backend_name_copy(chart_name, (backend_options & BACKEND_OPTION_SEND_NAMES && st->name)?st->name:st->id, RRD_ID_LENGTH_MAX);
+    backend_name_copy(dimension_name, (backend_options & BACKEND_OPTION_SEND_NAMES && rd->name)?rd->name:rd->id, RRD_ID_LENGTH_MAX);
+
+    buffer_sprintf(
+            b
+            , "%s.%s.%s.%s%s%s " COLLECTED_NUMBER_FORMAT " %llu\n"
+            , prefix
+            , hostname
+            , chart_name
+            , dimension_name
+            , (host->tags)?";":""
+            , (host->tags)?host->tags:""
+            , rd->last_collected_value
+            , (unsigned long long)rd->last_collected_time.tv_sec
+    );
+
+    return 1;
+}
+
+int format_dimension_stored_graphite_plaintext(
+        BUFFER *b                 // the buffer to write data to
+        , const char *prefix        // the prefix to use
+        , RRDHOST *host             // the host this chart comes from
+        , const char *hostname      // the hostname (to override host->hostname)
+        , RRDSET *st                // the chart
+        , RRDDIM *rd                // the dimension
+        , time_t after              // the start timestamp
+        , time_t before             // the end timestamp
+        , BACKEND_OPTIONS backend_options // BACKEND_SOURCE_* bitmap
+) {
+    (void)host;
+
+    char chart_name[RRD_ID_LENGTH_MAX + 1];
+    char dimension_name[RRD_ID_LENGTH_MAX + 1];
+    backend_name_copy(chart_name, (backend_options & BACKEND_OPTION_SEND_NAMES && st->name)?st->name:st->id, RRD_ID_LENGTH_MAX);
+    backend_name_copy(dimension_name, (backend_options & BACKEND_OPTION_SEND_NAMES && rd->name)?rd->name:rd->id, RRD_ID_LENGTH_MAX);
+
+    time_t first_t = after, last_t = before;
+    calculated_number value = backend_calculate_value_from_stored_data(st, rd, after, before, backend_options, &first_t, &last_t);
+
+    if(!isnan(value)) {
+
+        buffer_sprintf(
+                b
+                , "%s.%s.%s.%s%s%s " CALCULATED_NUMBER_FORMAT " %llu\n"
+                , prefix
+                , hostname
+                , chart_name
+                , dimension_name
+                , (host->tags)?";":""
+                , (host->tags)?host->tags:""
+                , value
+                , (unsigned long long) last_t
+        );
+
+        return 1;
+    }
+    return 0;
+}
+
+int process_graphite_response(BUFFER *b) {
+    return discard_response(b, "graphite");
+}
+
+
diff --git a/backends/graphite/graphite.h b/backends/graphite/graphite.h
new file mode 100644
index 0000000000..b7b0930fa9
--- /dev/null
+++ b/backends/graphite/graphite.h
@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+
+#ifndef NETDATA_BACKEND_GRAPHITE_H
+#define NETDATA_BACKEND_GRAPHITE_H
+
+#include "backends/backends.h"
+
+extern int format_dimension_collected_graphite_plaintext(
+          BUFFER *b                 // the buffer to write data to
+        , const char *prefix        // the prefix to use
+        , RRDHOST *host             // the host this chart comes from
+        , const char *hostname      // the hostname (to override host->hostname)
+        , RRDSET *st                // the chart
+        , RRDDIM *rd                // the dimension
+        , time_t after              // the start timestamp
+        , time_t before             // the end timestamp
+        , BACKEND_OPTIONS backend_options // BACKEND_SOURCE_* bitmap
+);
+
+extern int format_dimension_stored_graphite_plaintext(
+          BUFFER *b                 // the buffer to write data to
+        , const char *prefix        // the prefix to use
+        , RRDHOST *host             // the host this chart comes from
+        , const char *hostname      // the hostname (to override host->hostname)
+        , RRDSET *st                // the chart
+        , RRDDIM *rd                // the dimension
+        , time_t after              // the start timestamp
+        , time_t before             // the end timestamp
+        , BACKEND_OPTIONS backend_options // BACKEND_SOURCE_* bitmap
+);
+
+extern int process_graphite_response(BUFFER *b);
+
+#endif //NETDATA_BACKEND_GRAPHITE_H