69 lines
1.7 KiB
Markdown
69 lines
1.7 KiB
Markdown
# Working with packages
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In go, every project, is, at some part, a package.
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A package is simply a directory containing go source file.
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## Organising projects
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In your project, you may need multiple, isolated packages. Here is the most
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common project layout in found and I used in all my projects :
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```txt
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layout -- top project directory
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├── build -- all things related to ci
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│ └── ci
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│ └── ci.yml
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├── cmd -- main package, entrypoing
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│ └── layout.go
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├── Dockerfile -- container build instructions
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├── init -- if usefull systemd service file
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│ └── layout.service
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├── internal -- private packages, ie not to be used in another project
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│ └── private
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│ └── private.go
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├── LICENSE -- license file
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├── pkg -- public packages, ie packages like libs, to be importer in another project
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│ └── public
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│ └── public.go
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└── README.md -- readme
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```
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## Using go mod
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Init project
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```shell
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go mod init github.com/username/project
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```
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### Add an external dep to your project
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Import the required package
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```go
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import "github.com/example/lib"
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```
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The next time you will run a go command it will fetch the package, eg :
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```shell
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go build
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```
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### In repository packages
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Of course, you can also use isolated package you write inside your repository (usefull if you need to split things up)
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Let's say, for example, I want to add a new public package `foo` in my project,
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```shell
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mkdir -p pkg/foo && echo "package foo" > pkg/foo/foo.go
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```
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After adding stuff in your `foo.go` file, import it using
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```go
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import "github.com/username/project/foo"
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```
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