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Go resource embedding library which doesn't requirego generate at all.

Resource Embedding in Go is cumbersome especially when it involves custom commands andgo generate.assets is another resource embedding library which doesn't require any of them.It extracts a zip file bundled with your binary and provides a file path to the contents.

• no custom commands
• nogo generate
• only requirescat andzip whengo build
• uses local files whengo run orgo test
• easily extendable interface

We assume you have a Go project and a directory namedassets for resources in the project root.This directory name can be easily configured but for the sake of explanation we call the directoryassets.

$ tree ..├── Makefile├── assets│   └── templates│       └── hello.tmpl└── main.go2 directories, 3 files

First go get the library.

$ go get github.com/ichiban/assets

Then import it.

import "github.com/ichiban/assets"

In Go files, we can get the locator which points toassets directory by callingassets.New().Note that we'll need to close it in the end.

l,err:=assets.New()iferr!=nil {log.Fatalf("assets.New() failed: %v",err)}deferl.Close()log.Printf("assets: %s",l.Path)

When we build it and bundle with a resource zip file, the locator will point to the contents of the zip file which is extracted into a temporary directory.

To start with, we need to build the binary as usual.

$ mkdir -p bin $ go build -o bin/hello

Then, zip resources into a zip file.We need to enterassets directory to make a proper zip file.

$ mkdir -p zip$ cd assets$ zip -r ../zip/assets.zip .  adding: templates/ (stored 0%)  adding: templates/hello.tmpl (stored 0%)$ cd ..

A proper zip file looks like this:

$ unzip -l zip/assets.zip Archive:  zip/assets.zip  Length      Date    Time    Name---------  ---------- -----   ----        0  11-05-2018 22:31   templates/       14  11-05-2018 21:31   templates/hello.tmpl---------                     -------       14                     2 files

Finally, we can bundle resources bycat the binary and the zip file.Prepending an executable makes the zip offset values off by the size of the executable.We can fix the offsets byzip -A (zip --adjust-sfx).

$ cat bin/hello zip/assets.zip > bin/hello-bundled$ zip -A bin/hello-bundled Zip entry offsets appear off by 3345496 bytes - correcting...$ chmod +x bin/hello-bundled

Interestingly, the bundled binary is an executable and also a zip file.

$ unzip -l bin/hello-bundled Archive:  bin/hello-bundled  Length      Date    Time    Name---------  ---------- -----   ----        0  11-05-2018 22:31   templates/       14  11-05-2018 21:31   templates/hello.tmpl---------                     -------       14                     2 files

$ bin/hello-bundled 2018/11/30 16:22:13 assets: /var/folders/xt/6z9sk1dx1d734ltxxst16_h00000gn/T/hello-bundled882816570Hello, World!

This project is licensed under the MIT License - see theLICENSE.md file for details.

This project is inspired byZgok.