influxdb-cpp

A header-only C++ query & write client for InfluxDB.

• Support versions:
  • InfluxDB v0.9 ~ 2.0+
  • Check yourself while using other versions.

Why use influxdb-cpp?

• Exactly-small:
  • Less than 300 lines and only 10KB+.
• Easy-to-use:
  • It's designed to be used without extra studies.
• Easy-to-assemble:
  • Only a tiny header file needs to be included.
• No-dependencies:
  • Unless STL and std C libraries.

Examples

Before using

• The very simple thing you should do before using is only:

  #include "influxdb.hpp"

Writing example

• You should refer to the write syntax while writing series(metrics).

  measurement[,tag-key=tag-value...] field-key=field-value[,field2-key=field2-value...] [unix-nano-timestamp]
  

• You can rapidly start writing serires by according to the following example.

  influxdb_cpp::server_info si("127.0.0.1", 8086, "db", "usr", "pwd");
  influxdb_cpp::builder()
      .meas("foo")
      .tag("k", "v")
      .tag("x", "y")
      .field("x", 10)
      .field("y", 10.3, 2)
      .field("z", 10.3456)
      .field("b", !!10)
      .timestamp(1512722735522840439)
      .post_http(si);

  • Remarks:
    • 3rd parameter precision of field() is optional for floating point value, and default precision is 2.
    • usr and pwd is optional for authorization.

• The series sent is:

  foo,k=v,x=y x=10i,y=10.30,z=10.35,b=t 1512722735522840439
  

• You could change post_http to send_udp for udp request. And only host and port is required for udp.

  influxdb_cpp::builder()
      .meas("foo")
      .field("x", 10)
      .send_udp("127.0.0.1", 8091);

• Bulk/batch/multiple insert also supports:

  influxdb_cpp::builder()
      .meas("foo")  // series 1
      .field("x", 10)
  
      .meas("bar")  // series 2
      .field("y", 10.3)
      .send_udp("127.0.0.1", 8091);

• The series sent are:

  foo x=10i
  bar y=10.30
  

Query example

• And you can query series by according to the following example.

  influxdb_cpp::server_info si("127.0.0.1", 8086, "db", "usr", "pwd");
  
  string resp;
  influxdb_cpp::query(resp, "select * from t", si);

• You can use xpjson to parse the result refer to issue #3.

Remarks for Windows

• You should init socket environment by yourself under Windows.
  • FYR: MSDN doc for WSAStartup

Remarks for Special Characters in Password

• You should do URL encode first.

  string encoded_pwd;
  influxdb_cpp::url_encode(encoded_pwd, pwd);

Return code cheat-sheet

Functions	Code	Description
send_udp post_http	0	success
send_udp post_http	-1	convert host address to network order error
send_udp post_http	-2	create socket error
send_udp post_http	-3	sendto / connect failed
post_http	-6	send buffer error
post_http	-7	expect a character but read no more
post_http	-8	unexpected characters while parsing chunk length
post_http	-9	unexpected characters while parsing new line
post_http	-10	unexpected null character
post_http	-11	unexpected end

TODO

• Add more test cases.
• Supports DSN initializatin for server_info.
• Do not need to connect every time.

Misc

• Please feel free to use influxdb-cpp.
• Looking forward to your suggestions.
• If your project is using influxdb-cpp, you can show your project or company here by creating a issue or let me know.