out_influxdb: Handle signed/unsigned integer as influx's integer of t…

…hat representation

This is because in their line protocol, it needs to add "i" suffix for
handling a value as an integer:

| Datatype | Element(s)   | Description |
|:--------:|:------------:|:------------|
| Integger | Field values | Signed 64-bit integers (-9223372036854775808 to 9223372036854775807). Specify an integer with a trailing i on the number. Example: 1i |

So, we need to add "i" suffix for signed/unsigned integer values.

ref: https://docs.influxdata.com/influxdb/v1/write_protocols/line_protocol_reference/

Signed-off-by: Hiroshi Hatake <[email protected]>

plugins/out_influxdb/influxdb.c

@@ -171,11 +171,11 @@ static char *influxdb_format(const char *tag, int tag_len,
             }
             else if (v->type == MSGPACK_OBJECT_POSITIVE_INTEGER) {
                 val = tmp;
-                val_len = snprintf(tmp, sizeof(tmp) - 1, "%" PRIu64, v->via.u64);
+                val_len = snprintf(tmp, sizeof(tmp) - 1, "%" PRIu64 "i", v->via.u64);
             }
             else if (v->type == MSGPACK_OBJECT_NEGATIVE_INTEGER) {
                 val = tmp;
-                val_len = snprintf(tmp, sizeof(tmp) - 1, "%" PRId64, v->via.i64);
+                val_len = snprintf(tmp, sizeof(tmp) - 1, "%" PRId64 "i", v->via.i64);
             }
             else if (v->type == MSGPACK_OBJECT_FLOAT || v->type == MSGPACK_OBJECT_FLOAT32) {
                 val = tmp;