Docs: Edited Go Proxy topic

Related to: https://gitlab.com/gitlab-org/gitlab/-/issues/247950

doc/user/packages/go_proxy/index.md

@@ -4,11 +4,11 @@ group: Package
 info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#designated-technical-writers
 ---
 
-# GitLab Go Proxy
+# Go proxy for GitLab
 
 > - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/27376) in [GitLab Premium](https://about.gitlab.com/pricing/) 13.1.
 > - It's deployed behind a feature flag, disabled by default.
-> - It's disabled on GitLab.com.
+> - It's disabled for GitLab.com.
 > - It's not recommended for production use.
 > - To use it in GitLab self-managed instances, ask a GitLab administrator to [enable it](#enable-the-go-proxy).
 > - [Moved](https://gitlab.com/gitlab-org/gitlab/-/issues/221259) to GitLab Core in 13.3.
@@ -16,14 +16,12 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 With the Go proxy for GitLab, every project in GitLab can be fetched with the
 [Go proxy protocol](https://proxy.golang.org/).
 
-## Prerequisites
+## Enable the Go proxy
 
-### Enable the Go proxy
+The Go proxy for GitLab is under development, and isn't ready for production use
+due to [potential performance issues with large repositories](https://gitlab.com/gitlab-org/gitlab/-/issues/218083).
 
-The Go proxy for GitLab is under development and not ready for production use, due to
-[potential performance issues with large repositories](https://gitlab.com/gitlab-org/gitlab/-/issues/218083).
-
-It is deployed behind a feature flag that is **disabled by default**.
+It's deployed behind a feature flag that is _disabled by default_.
 
 [GitLab administrators with access to the GitLab Rails console](../../../administration/feature_flags.md)
 can enable it for your instance.
@@ -47,57 +45,46 @@ Feature.enable(:go_proxy, Project.find(1))
 Feature.disable(:go_proxy, Project.find(2))
 ```
 
-### Enable the Package Registry
-
-The Package Registry is enabled for new projects by default. If you cannot find
-the **Packages > List** entry under your project's sidebar, verify
-the following:
-
-1. Your GitLab administrator has
-   [enabled support for the Package Registry](../../../administration/packages/index.md).
-1. The Package Registry is [enabled for your project](../index.md).
-
 NOTE: **Note:**
-GitLab does not currently display Go modules in the **Packages Registry** of a project.
-Follow [this issue](https://gitlab.com/gitlab-org/gitlab/-/issues/213770) for details.
+Even if it's enabled, GitLab doesn't display Go modules in the **Package Registry**.
+Follow [this issue](https://gitlab.com/gitlab-org/gitlab/-/issues/213770) for
+details.
 
 ## Add GitLab as a Go proxy
 
-NOTE: **Note:**
-To use a Go proxy, you must be using Go 1.13 or later.
-
-The available proxy endpoints are:
+To use GitLab as a Go proxy, you must be using Go 1.13 or later.
 
-- Project - can fetch modules defined by a project - `/api/v4/projects/:id/packages/go`
+The available proxy endpoint is for fetching modules by project: `/api/v4/projects/:id/packages/go`
 
-To use the Go proxy for GitLab to fetch Go modules from GitLab, add the
-appropriate proxy endpoint to `GOPROXY`. For details on setting Go environment
-variables, see [Set environment variables](#set-environment-variables). For
-details on configuring `GOPROXY`, see [Dependency Management in Go >
-Proxies](../../../development/go_guide/dependencies.md#proxies).
+To fetch Go modules from GitLab, add the project-specific endpoint to `GOPROXY`.
 
-For example, adding the project-specific endpoint to `GOPROXY` will tell Go
-to initially query that endpoint and fall back to the default behavior:
+Go queries the endpoint and falls back to the default behavior:
 
 ```shell
-go env -w GOPROXY='https://gitlab.com/api/v4/projects/1234/packages/go,https://proxy.golang.org,direct'
+go env -w GOPROXY='https://gitlab.example.com/api/v4/projects/1234/packages/go,https://proxy.golang.org,direct'
 ```
 
-With this configuration, Go fetches dependencies as follows:
+With this configuration, Go fetches dependencies in this order:
 
-1. Attempt to fetch from the project-specific Go proxy.
-1. Attempt to fetch from [proxy.golang.org](https://proxy.golang.org).
-1. Fetch directly with version control system operations (such as `git clone`,
+1. Go attempts to fetch from the project-specific Go proxy.
+1. Go attempts to fetch from [proxy.golang.org](https://proxy.golang.org).
+1. Go fetches directly with version control system operations (like `git clone`,
    `svn checkout`, and so on).
 
-If `GOPROXY` is not specified, Go follows steps 2 and 3, which corresponds to
-setting `GOPROXY` to `https://proxy.golang.org,direct`. If `GOPROXY` only
-contains the project-specific endpoint, Go will only query that endpoint.
+If `GOPROXY` isn't specified, Go follows steps 2 and 3, which corresponds to
+setting `GOPROXY` to `https://proxy.golang.org,direct`. If `GOPROXY`
+contains only the project-specific endpoint, Go queries only that endpoint.
+
+For details about how to set Go environment variables, see
+[Set environment variables](#set-environment-variables).
+
+For details about configuring `GOPROXY`, see
+[Dependency Management in Go > Proxies](../../../development/go_guide/dependencies.md#proxies).
 
 ## Fetch modules from private projects
 
-`go` does not support transmitting credentials over insecure connections. The
-steps below work only if GitLab is configured for HTTPS.
+`go` doesn't support transmitting credentials over insecure connections. The
+following steps work only if GitLab is configured for HTTPS:
 
 1. Configure Go to include HTTP basic authentication credentials when fetching
    from the Go proxy for GitLab.
@@ -107,31 +94,37 @@ steps below work only if GitLab is configured for HTTPS.
 ### Enable request authentication
 
 Create a [personal access token](../../profile/personal_access_tokens.md) with
-the `api` or `read_api` scope and add it to
-[`~/.netrc`](https://ec.haxx.se/usingcurl/usingcurl-netrc):
+the scope set to `api` or `read_api`. 
 
-```netrc
+Add it to [`~/.netrc`](https://ec.haxx.se/usingcurl/usingcurl-netrc):
+
+```shell
 machine <url> login <username> password <token>
 ```
 
-`<url>` should be the URL of the GitLab instance, for example `gitlab.com`.
-`<username>` and `<token>` should be your username and the personal access
-token, respectively.
+- `<url>`: The GitLab URL, for example `gitlab.com`.
+- `<username>`: Your username.
+- `<token>`: Your personal access token.
 
 ### Disable checksum database queries
 
-When downloading dependencies, by default Go 1.13 and later validate fetched
-sources against the checksum database `sum.golang.org`. If the checksum of the
-fetched sources does not match the checksum from the database, Go will not build
-the dependency. This causes private modules to fail to build, as
-`sum.golang.org` cannot fetch the source of private modules and thus cannot
-provide a checksum. To resolve this issue, `GONOSUMDB` should be set to a
-comma-separated list of private projects. For details on setting Go environment
-variables, see [Set environment variables](#set-environment-variables). For more
-details on disabling this feature of Go, see [Dependency Management in Go >
-Checksums](../../../development/go_guide/dependencies.md#checksums).
+When downloading dependencies with Go 1.13 and later, fetched sources are
+validated against the checksum database `sum.golang.org`.
+
+If the checksum of the fetched sources doesn't match the checksum from the
+database, Go doesn't build the dependency. 
+
+Private modules fail to build because `sum.golang.org` can't fetch the source
+of private modules, and so it cannot provide a checksum.
 
-For example, to disable checksum queries for `gitlab.com/my/project`, set `GONOSUMDB`:
+To resolve this issue, set `GONOSUMDB` to a comma-separated list of private
+projects. For details about setting Go environment variables, see
+[Set environment variables](#set-environment-variables). For more details about
+disabling this feature of Go, see
+[Dependency Management in Go > Checksums](../../../development/go_guide/dependencies.md#checksums).
+
+For example, to disable checksum queries for `gitlab.com/my/project`, set
+`GONOSUMDB`:
 
 ```shell
 go env -w GONOSUMDB='gitlab.com/my/project,<previous value>'
@@ -139,32 +132,36 @@ go env -w GONOSUMDB='gitlab.com/my/project,<previous value>'
 
 ## Working with Go
 
-If you are unfamiliar with managing dependencies in Go, or Go in general,
-consider reviewing the following documentation:
+If you're unfamiliar with managing dependencies in Go, or Go in general, review
+the following documentation:
 
 - [Dependency Management in Go](../../../development/go_guide/dependencies.md)
 - [Go Modules Reference](https://golang.org/ref/mod)
-- [Documentation (golang.org)](https://golang.org/doc/)
-- [Learn (learn.go.dev)](https://learn.go.dev/)
+- [Documentation (`golang.org`)](https://golang.org/doc/)
+- [Learn (`learn.go.dev`)](https://learn.go.dev/)
 
 ### Set environment variables
 
-Go uses environment variables to control various features. These can be managed
-in all the usual ways, but Go 1.14 will read and write Go environment variables
-from and to a special Go environment file, `~/.go/env` by default. If `GOENV` is
-set to a file, Go will read and write that file instead. If `GOENV` is not set
-but `GOPATH` is set, Go will read and write `$GOPATH/env`.
+Go uses environment variables to control various features. You can manage these
+variables in all the usual ways. However, Go 1.14 reads and writes Go
+environment variables to and from a special Go environment file, `~/.go/env` by
+default.
+
+- If `GOENV` is set to a file, Go reads and writes to and from that file instead.
+- If `GOENV` is not set but `GOPATH` is set, Go reads and writes `$GOPATH/env`.
 
 Go environment variables can be read with `go env <var>` and, in Go 1.14 and
-later, can be written with `go env -w <var>=<value>`. For example, `go env
-GOPATH` or `go env -w GOPATH=/go`.
+later, can be written with `go env -w <var>=<value>`. For example,
+`go env GOPATH` or `go env -w GOPATH=/go`.
 
 ### Release a module
 
 Go modules and module versions are defined by source repositories, such as Git,
-SVN, Mercurial, and so on. A module is a repository containing `go.mod` and Go
-files. Module versions are defined by VCS tags. To publish a module, push
-`go.mod` and source files to a VCS repository. To publish a module version, push
-a VCS tag. See [Dependency Management in Go >
-Versioning](../../../development/go_guide/dependencies.md#versioning) for more
-details on what constitutes a valid module or module version.
+SVN, and Mercurial. A module is a repository that contains `go.mod` and Go
+files. Module versions are defined by VCS tags.
+
+To publish a module, push `go.mod` and source files to a VCS repository. To
+publish a module version, push a VCS tag.
+
+See [Dependency Management in Go > Versioning](../../../development/go_guide/dependencies.md#versioning)
+for more details about what constitutes a valid module or module version.