TSDB handling isolation.

Isolate API from DB Backend so you could rely on different TSDB backend

Change-Id: Ie74347e8175c7e0ed508f6b1e61a1c504b2a2ebb
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>

1 files changed, 173 insertions, 0 deletions

diff --git a/src/plugins/influxdb.c b/src/plugins/influxdb.c
new file mode 100644
index 0000000..74c1297
--- /dev/null
+++ b/src/plugins/influxdb.c
@@ -0,0 +1,173 @@
+/*
+ * Copyright (C) 2015, 2016, 2017, 2018 "IoT.bzh"
+ * Author "Romain Forlot" <romain.forlot@iot.bzh>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *	 http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "tsdb.h"
+
+int create_database()
+{
+	int ret = 0;
+	char *result;
+	size_t result_size;
+
+	// Declare query to be posted
+	const char *post_data[2];
+	post_data[0] = "q=CREATE DATABASE \""DEFAULT_DB"\"";
+	post_data[1] = NULL;
+
+	CURL *request = curl_wrap_prepare_post("localhost:"DEFAULT_DBPORT"/query",NULL, 1, post_data);
+	curl_wrap_perform(request, &result, &result_size);
+
+	if(curl_wrap_response_code_get(request) != 200) {
+		AFB_ERROR("Can't create database.");
+		ret = -1;
+	}
+
+	curl_easy_cleanup(request);
+	free(post_data);
+
+	if(ret == 0)
+		AFB_NOTICE("Database 'agl-collector' created");
+
+	return ret;
+}
+
+void influxdb_cb(void *closure, int status, CURL *curl, const char *result, size_t size)
+{
+	struct afb_req *req = (struct afb_req*)closure;
+	long rep_code = curl_wrap_response_code_get(curl);
+	switch(rep_code) {
+		case 204:
+			AFB_DEBUG("Request correctly written");
+			afb_req_success(*req, NULL, "Request has been successfully writen");
+			break;
+		case 400:
+			afb_req_fail(*req, "Bad request", result);
+			break;
+		case 401:
+			afb_req_fail(*req, "Unauthorized access", result);
+			break;
+		case 404:
+			afb_req_fail(*req, "Not found", result);
+			AFB_NOTICE("Attempt to create the DB '"DEFAULT_DB"'");
+			create_database();
+			break;
+		case 500:
+			afb_req_fail_f(*req, "Timeout", "Overloaded server: %s", result);
+			break;
+		default:
+			afb_req_fail(*req, "Failure", "Unexpected behavior.");
+			break;
+	}
+}
+
+int unpack_metric(json_object *m, const char **name, const char **source, const char **unit, const char **identity, json_object **jv, uint64_t *timestamp)
+{
+	if (wrap_json_unpack(m, "{ss,s?s,s?s,s?s,so,sI!}",
+					"name", name,
+					"source", source,
+					"unit", unit,
+					"identity", identity,
+					"value", jv,
+					"timestamp", timestamp))
+		return -1;
+	else if (!json_object_is_type(*jv, json_type_boolean) &&
+			 !json_object_is_type(*jv, json_type_double) &&
+			 !json_object_is_type(*jv, json_type_int) &&
+			 !json_object_is_type(*jv, json_type_string))
+		return -1;
+
+	return 0;
+}
+
+void concatenate(char* dest, const char* source, const char *sep)
+{
+	strncat(dest, sep, strlen(sep));
+	strncat(dest, source, strlen(source));
+}
+
+char *format_write_query(char *query, const char *name, const char *source, const char *unit, const char *identity, json_object *jv, uint64_t timestamp)
+{
+	char *ts;
+	memset(query, 0, URL_MAXIMUM_LENGTH);
+
+	strncat(query, name, strlen(name));
+	if (source) {
+		concatenate(query, source, ",");
+	}
+	if (unit) {
+		concatenate(query, unit, ",");
+	}
+	if (identity) {
+		concatenate(query, identity, ",");
+	}
+
+	concatenate(query, "value", " ");
+	concatenate(query, json_object_to_json_string(jv), "=");
+	asprintf(&ts, "%lu", timestamp);
+	concatenate(query, ts, " ");
+
+	return query;
+}
+
+CURL *make_curl_write_post(const char *url, struct json_object *metric)
+{
+	CURL *curl;
+	const char *name = NULL,
+			*source = NULL,
+			*unit = NULL,
+			*identity = NULL;
+
+	size_t lpd = json_object_is_type(metric, json_type_array) ?
+				 json_object_array_length(metric) + 1 : 2;
+
+	char **post_data;
+	post_data = malloc(lpd);
+
+	char query[URL_MAXIMUM_LENGTH];
+	bzero(query, URL_MAXIMUM_LENGTH);
+
+	json_object *jv = NULL;
+	uint64_t timestamp = 0;
+
+	if(unpack_metric(metric, &name, &source, &unit, &identity, &jv, &timestamp)) {
+		AFB_ERROR("ERROR unpacking metric. %s", json_object_to_json_string(metric));
+		curl = NULL;
+	}
+	else {
+		for(int i = lpd; i != 0; i--) {
+			format_write_query(query, name, source, unit, identity, jv, timestamp);
+			post_data[i] = i == lpd ? NULL : query;
+		}
+		curl = curl_wrap_prepare_post(url, NULL, 1, (const char * const*)post_data);
+	}
+
+	return curl;
+}
+
+CURL *influxdb_write(const char* host, int port, json_object *metric)
+{
+	char url[URL_MAXIMUM_LENGTH]; /* Safe limit for most popular web browser */
+	memset(url, 0, sizeof(url));
+
+	/* Handle default host and port */
+	host = host ? host : DEFAULT_DBHOST;
+	port = port > 0 ? port : atoi(DEFAULT_DBPORT);
+
+	strncat(url, host, strlen(host));
+	strncat(url, ":"DEFAULT_DBPORT"/write?db="DEFAULT_DB, strlen(":"DEFAULT_DBPORT"/write?db="DEFAULT_DB));
+	curl_request = make_curl_write_post(url, metric);
+}