error in when installing rain_server with cargo

[chenray844]

@all

hi all:

I install rain_server with cargo install -v rain_server, but can not install rain_server successfully.

error as showing below

error: failed to run custom build command for `rain_core v0.3.0`
process didn't exit successfully: `/var/folders/y3/xb_8fx894lq_89d7kv0k3gq00000gp/T/cargo-install.LarbQVDOQLHm/release/build/rain_core-211500adc0948f2e/build-script-build` (exit code: 101)
--- stderr
thread 'main' panicked at 'schema compiler command: Error { kind: Failed, description: "Error while trying to execute `capnp compile`: Failed: No such file or directory (os error 2).  Please verify that version 0.5.2 or higher of the capnp executable is installed on your system. See https://capnproto.org/install.html" }', src/libcore/result.rs:906:4
note: Run with `RUST_BACKTRACE=1` for a backtrace.

warning: build failed, waiting for other jobs to finish...
error: failed to run custom build command for `capnp-rpc v0.8.3`
process didn't exit successfully: `/var/folders/y3/xb_8fx894lq_89d7kv0k3gq00000gp/T/cargo-install.LarbQVDOQLHm/release/build/capnp-rpc-9631959463f9bb8f/build-script-build` (exit code: 101)
--- stderr
thread 'main' panicked at 'capnp compile: Error { kind: Failed, description: "Error while trying to execute `capnp compile`: Failed: No such file or directory (os error 2).  Please verify that version 0.5.2 or higher of the capnp executable is installed on your system. See https://capnproto.org/install.html" }', src/libcore/result.rs:906:4
note: Run with `RUST_BACKTRACE=1` for a backtrace.

warning: build failed, waiting for other jobs to finish...
error: failed to compile `rain_server v0.3.0`, intermediate artifacts can be found at `/var/folders/y3/xb_8fx894lq_89d7kv0k3gq00000gp/T/cargo-install.LarbQVDOQLHm`

Caused by:
  build failed

cargo version :

cargo -V
cargo 0.23.0 (61fa02415 2017-11-22)

Is there something wrong when using cargo install rain_server?

[chenray844]

I follows the install doc for capnp at https://capnproto.org/install.html

brew install capnp
cargo install rain_server

at finally, I installed rain successfully.