The PushNotification object is quite big (772 bytes on AMD64),
so avoid doing too many copying without a need.
Collect pointers and do copying only when sending into a channel.
Found using https://go-critic.github.io/overview#rangeValCopy-ref
Linter output:
```
$GOPATH/src/github.com/appleboy/gorush/gorush/worker.go:38:2: rangeValCopy: each iteration copies 772 bytes (consider pointers or indexing)
$GOPATH/src/github.com/appleboy/gorush/gorush/worker.go:53:2: rangeValCopy: each iteration copies 772 bytes (consider pointers or indexing)
```
This patch simply adds `openbsd` to `TARGETS`. This is a supported Go architecture and the result will be binaries that can be run on 32 or 64-bit OpenBSD.
This project is hard to build on OpenBSD because it depends on some Linux-isms like *GNU Make* and specific `find` options. So it will be nice to have binaries easily available.
At the moment you can't start gorush with IOS base64 certificate provided using an ENV var.
Apparently viper uses default value for the configuration field even if you set env var to an empty string. So `if var is not set` or `is set and string is empty` => default value.
Which means that if I only use env vars for configuration and I want to use IOS certificate in base64 I can not set `cert_path` to an empty string, so `gorush` uses base64 cert:
https://github.com/appleboy/gorush/blob/master/gorush/notification.go#L180
I.e.:
```
ORUSH_IOS_ENABLED=true GORUSH_IOS_KEY_PATH="" GORUSH_IOS_KEY_TYPE=p12 GORUSH_IOS_KEY_BASE64="SOME_BASE64" go run main.go
(config.SectionIos) {
Enabled: (bool) true,
KeyPath: (string) (len=7) "key.pem", <--- still key.pem
KeyBase64: (string) (len=2) "SOME_BASE64",
KeyType: (string) (len=3) "p12",
Password: (string) "",
Production: (bool) false,
MaxRetry: (int) 0,
KeyID: (string) "",
TeamID: (string) ""
}
FATA[2018/06/10 - 12:42:09] certificate file does not exist
```
So by default `KeyPath` should an empty string. Then I can set only if I want.
Bo-Yi Wu
Dmitry Dorogin
Iskander (Alex) Sharipov
Eduard Pelesh
Stefan Arentz
sysradium