gaper
Used to build and restart a Go project when it crashes or some watched file changes
Aimed to be used in development only.
---
[](LICENSE.md)
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## Changelog
See [Releases](https://github.com/maxcnunes/gaper/releases) for detailed history changes.
## Installation
Using go tooling:
```
go get -u github.com/maxcnunes/gaper/cmd/gaper
```
Or, downloading the binary instead (example for version 1.1.0, make sure you are using the latest version though):
```
curl -SL https://github.com/maxcnunes/gaper/releases/download/v1.1.0/gaper_1.1.0_linux_amd64.tar.gz | tar -xvzf - -C "${GOPATH}/bin"
```
## Usage
```
NAME:
gaper - Used to build and restart a Go project when it crashes or some watched file changes
USAGE:
gaper [global options] command [command options] [arguments...]
VERSION:
version
COMMANDS:
help, h Shows a list of commands or help for one command
GLOBAL OPTIONS:
--bin-name value name for the binary built by gaper for the executed program (default current directory name)
--build-path value path to the program source code (default: ".")
--build-args value arguments used on building the program
--program-args value arguments used on executing the program
--verbose turns on the verbose messages from gaper
--disable-default-ignore turns off default ignore for hidden files and folders, "*_test.go" files, and vendor folder
--watch value, -w value list of folders or files to watch for changes
--ignore value, -i value list of folders or files to ignore for changes
--poll-interval value, -p value how often in milliseconds to poll watched files for changes (default: 500)
--extensions value, -e value extensions to watch for changes (default: "go")
--no-restart-on value, -n value don't automatically restart the supervised program if it ends:
if "error", an exit code of 0 will still restart.
if "exit", no restart regardless of exit code.
if "success", no restart only if exit code is 0.
--help, -h show help
--version, -v print the version
```
### Watch and Ignore paths
For those options Gaper supports static paths (e.g. `build/`, `seed.go`) or glob paths (e.g. `migrations/**/up.go`, `*_test.go`).
On using a path to a directory please add a `/` at the end (e.g. `build/`) to make sure Gaper won't include other matches that starts with that same value (e.g. `build/`, `build_settings.go`).
### Default ignore settings
Since in most projects there is no need to watch changes for:
* hidden files and folders
* test files (`*_test.go`)
* vendor folder
Gaper by default ignores those cases already. Although, if you need Gaper to watch those files anyway it is possible to disable this setting with `--disable-default-ignore` argument.
### Watch method
Currently Gaper uses polling to watch file changes. We have plans to [support fs events](https://github.com/maxcnunes/gaper/issues/12) though in a near future.
### Examples
Using all defaults provided by Gaper:
```
gaper
```
Example providing a few custom configurations:
```
gaper \
--bin-name build/api-dev \
--build-path cmd/server \
--build-args "-ldflags=\"-X 'main.Version=dev'" \
-w 'public/**' -w '*.go' \
-e js -e css -e html \
--ignore './**/*_mock.go' \
--program-args "-arg1 ok -arg2=nope" \
--watch .
```
## Contributing
See the [Contributing guide](/CONTRIBUTING.md) for steps on how to contribute to this project.
## Reference
This package was heavily inspired by [gin](https://github.com/codegangsta/gin) and [node-supervisor](https://github.com/petruisfan/node-supervisor).
Basically, Gaper is a mixing of those projects above. It started from **gin** code base and I rewrote it aiming to get
something similar to **node-supervisor** (but simpler). A big thanks for those projects and for the people behind it!
:clap::clap:
### How is Gaper different of Gin
The main difference is that Gaper removes a layer of complexity from Gin which has a proxy running on top of
the executed server. It allows to postpone a build and reload the server when the first call hits it. With Gaper
we don't care about that feature, it just restarts your server whenever a change is made.