Merge pull request #2547 from pavelzw/example-recipes-go

add go example recipe

Author: xhochy

docs/_sidebar.json

@@ -54,7 +54,10 @@
           "type": "doc",
           "id": "maintainer/example_recipes/index"
         },
-        "items": ["maintainer/example_recipes/rust"]
+        "items": [
+          "maintainer/example_recipes/go",
+          "maintainer/example_recipes/rust"
+        ]
       }
     ]
   },

docs/maintainer/example_recipes/go.md

@@ -0,0 +1,83 @@
+---
+title: 'Go packages'
+---
+
+If you want to package a Go package to conda-forge, you can use this recipe template:
+
+```yaml
+context:
+  name: example-package
+  version: "0.1.0"
+
+package:
+  name: ${{ name|lower }}
+  version: ${{ version }}
+
+source:
+  url: https://github.com/example-package/${{ name }}/archive/refs/tags/v${{ version }}.tar.gz
+  sha256: 0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef
+  target_directory: src
+
+build:
+  number: 0
+  script:
+    - cd src
+    - go-licenses save . --save_path ../library_licenses
+    - if: unix
+      then: go build -v -o $PREFIX/bin/example-package -ldflags="-s -w"
+      else: go build -v -o %LIBRARY_BIN%\example-package.exe -ldflags="-s"
+
+requirements:
+  build:
+    - ${{ compiler("go-nocgo") }}
+    - go-licenses
+
+tests:
+  - script: example-package -help
+  - package_contents:
+    bin:
+      - example-package
+    strict: true
+
+about:
+  homepage: https://github.com/example-package/example-package
+  summary: Summary of the package.
+  description: |
+    Description of the package
+  license: MIT
+  license_file:
+    - src/LICENSE
+    - library_licenses/
+  documentation: https://pkg.go.dev/github.com/example-package/example-package
+  repository: https://github.com/example-package/example-package
+
+extra:
+  recipe-maintainers:
+    - LandoCalrissian
+```
+
+This recipe template supports different features:
+
+- Package licenses of statically linked libraries.
+- Ensure only binary is created by using `strict: true` in the `package_contents` tests.
+
+If your package requires `cgo` instead of `go-nocgo`, you can use `${{ compiler("go-cgo") }}` instead to build the package. By default, the `go-nocgo` compiler [is used](https://github.com/conda-forge/staged-recipes/blob/main/.ci_support/linux64.yaml). Using `${{ compiler("go-cgo")) }}` also requires `${{ compiler("c") }}` and `${{ stdlib("c") }}` and may require `${{ compiler("cxx") }}` if C++ code is compiled. C/C++ build tools such as `make`, `autoconf`, `automake`, `libtool` or `cmake` may also be needed.
+
+Sometimes, `go-licenses` might fail to detect licenses for some packages. In such cases, you can manually download the license file from the official source and add `--ignore github.com/bad-package/bad-package` to the `go-licenses` invokation. See [here](https://github.com/conda-forge/k9s-feedstock/blob/7929e0d86c829ba2ca172f08926f9fb7e6398247/recipe/recipe.yaml) for an example.
+
+Some packages ship multiple binaries, in which case the `go build` command needs to be run separately for each binary.
+It is increasingly common for the go build command to require specifying a subdirectory, in which case the build steps would be slightly modified as shown below:
+
+```bash
+go-licenses save ./cmd/example-package --save-path ../library_licenses
+go build -v -o ${PREFIX}/bin/example-package -ldflags="-s -w" ./cmd/example-package
+```
+
+Some older Go packages that are not using Go modules yet can be converted by using:
+
+```bash
+go mod init
+go mod tidy
+```
+
+Additional steps maybe required depending on which Go dependency manager the project has been using.