Tapper main application; configures and starts application supervisor.

Automatically started when Tapper is included as dependency.

Configuration

Looks for configuration under :tapper key:

| reporter | atom | {atom, any} | function/1 | Module implementing Tapper.Reporter.Api ^[1], or function of arity 1 to use for reporting spans; defaults to Tapper.Reporter.Console. | | server_trace | atom | Logger level to log server traces at, or false (default false) |

All keys support the Phoenix-style {:system, var} format^[2], to allow lookup from shell environment variables, e.g. {:system, "PORT"} to read PORT environment variable.

Config values will be converted to the expected type, principally so that string values can be handled from environment variables:

• ip is expected in dotted IPV4 or colon IPV6 notation, see Erlang's inet:parse_address/1
• reporter can be specified as a string which will be converted to an atom, following Elixir's module name rules.

Example

In config.exs etc.:

config :tapper,
  system_id: "my-cool-svc",
  reporter: Tapper.Reporter.Zipkin,
  port: {:system, "PORT"}

^[1] If the reporter is given as {module, arg} it is expected to specify an OTP server to be started under Tapper's main supervisor.<br/> ^[2] Tapper uses the DeferredConfig library to resolve all configuration under the :tapper key, so see its documention for more options.