summercms/docs/plugins/marketplace.md

---
title: Publishing plugins
description: Describe a plugin with a generated plugin.yaml, install listed plugins with summer plugin:install, and read the registry API.
section: plugins
order: 50
---
# Publishing plugins

A plugin that lives in its own repository can be listed on the SummerCMS marketplace. The listing reads one file from the repository, `plugin.yaml`, which the `summer` tool generates from the plugin's own sources. Nothing in it is typed by hand, so the ID, module path and version requirements the marketplace shows are the ones the code has.

This is the counterpart of WinterCMS's `pluginDetails()` in `Plugin.php` together with the `composer.json` a marketplace plugin carries.

## The plugin.yaml manifest

`plugin.yaml` sits next to `plugin.go`, one per plugin package. A repository whose module holds a second plugin in a subdirectory has a second `plugin.yaml` in that subdirectory.

```yaml
# Generated by summer plugin:manifest. Do not edit; rerun the command.
schema: 1
id: acme.blog
module: example.com/acme/sm-blog-plugin
package: example.com/acme/sm-blog-plugin
name: Blog
description: Posts, categories and a feed for SummerCMS applications.
framework: v0.6.0
requires:
  acme.translate: v0.2.0
overrides:
  name: Blog
```

| Field | Comes from |
|-------|------------|
| `schema` | The format version (`kiosk.SchemaVersion`). A reader that knows an older schema refuses the file and asks you to update `summer`. |
| `id` | What `ID()` in `plugin.go` returns: a string literal or a constant (of the same package, of another package of the module, or of a required module). The command reads the source and never runs it; any other expression, such as a function call or a variable, is an error naming `ID()`. |
| `module` | The `module` line of the nearest `go.mod`: what `go get` takes. |
| `package` | The plugin's import path: what `summer.yaml` lists. It differs from `module` for a plugin in a subdirectory. |
| `name` | The README's H1, or the `--name` override. |
| `description` | The first paragraph after the README's H1 (the one-sentence summary of the standard README structure), or the `--description` override. |
| `framework` | The version `go.mod` requires the framework (`git.golem15.com/golem15/summercms`) at: the oldest framework release the plugin works with. |
| `requires` | Each plugin ID `Requires()` returns (literals or constants, as for `id`), with the version `go.mod` requires its module at. A requirement at `v0.0.0` is an error, because nobody can install that version; a pseudo-version is accepted with a warning. The value is empty for a plugin in the same module, and for one whose module is not a `go.mod` require. Left out when `Requires()` returns none. |
| `overrides` | The `--name` and `--description` values, kept across regenerations. Left out when neither is set. |

Versions are minimums in Go's sense (`v0.6.0` means "v0.6.0 or newer"), never ranges: Go's minimal version selection picks the version, and a major version change moves the module path.

## Generating and checking it

Run `summer plugin:manifest` in the plugin directory, or pass the directory:

```sh
summer plugin:manifest
summer plugin:manifest plugins/acme/blog
summer plugin:manifest --pretend
```

`--pretend` prints the file instead of writing it. Commit `plugin.yaml`, and rerun the command after changing what it reads: the README's H1 or summary, `ID()` or `Requires()`, or a `go.mod` require.

A README whose H1 is the plugin ID (`# acme.blog`) has no display name to offer, so the command stops and asks for one. Give it once; it is stored under `overrides:` and reused:

```sh
summer plugin:manifest --name="Blog"
summer plugin:manifest --description="Posts, categories and a feed."
summer plugin:manifest --name=""
```

The last line clears the name override, so the README's H1 is used again.

`--check` writes nothing. It regenerates the manifest in memory and exits with status 1, printing what it expected, when `plugin.yaml` is missing or differs from the committed file:

```sh
summer plugin:manifest --check
```

Run it before tagging a release, so the tag carries a manifest that matches its code.

## Testing the manifest in your plugin

Add one test to the plugin, so `go test` fails as soon as `plugin.yaml` no longer matches the code. It imports `git.golem15.com/golem15/summercms/modules/kiosk` and passes the plugin directory, which is `"."` in a plugin's own package (the framework's copy below checks a fixture):

```go src=modules/kiosk/checkt_test.go#TestPluginManifest
// TestPluginManifest is the test a plugin repository adds next to its
// plugin.go, with "." as the directory. Here it guards the committed
// manifest of the literal fixture.
func TestPluginManifest(t *testing.T) {
	kiosk.CheckT(t, "testdata/literal")
}
```

`kiosk.CheckT` runs the same check as `summer plugin:manifest --check` and names the command to rerun. A nested plugin gets its own test in its own directory.

## Installed plugin metadata

`summer build` reads the `plugin.yaml` of every plugin the application lists and bakes the name and description into the generated `plugins.gen.go` as `PluginInfo`, next to each plugin's version and the framework version (`FrameworkVersion`). At start-up the application publishes them as `party.Installed`, which the admin's Plugins screen reads. [Go modules and workspaces](../architecture/go-modules-and-workspaces.md#the-summeryaml-manifest) explains where the versions come from.

## Installing plugins

`summer plugin:install` adds a listed plugin to an application. Run it inside the application:

```sh
summer plugin:install acme.blog
summer plugin:install acme.blog@v0.3.0
summer plugin:install acme.blog --yes
```

The command asks the registry for the plugin's releases and picks the newest one whose framework minimum the application meets. The application's framework version is the effective one: the newest tag of a local framework checkout when `go.mod` or `go.work` replaces the framework with a directory, otherwise the version `go.mod` requires. `@vX.Y.Z` pins a release, which must meet the framework minimum too. When every release needs a newer framework, the command stops and names the framework version to move to; it never changes the framework requirement itself.

The plugin is installed as a Go module: one `go get <module>@<version>` in the application, then an entry with its ID and package in `summer.yaml`. The edit appends to the `plugins:` list and keeps the file's comments and blank lines. Run `summer build` afterwards: it generates the import, and the new require in `go.mod` loses its `// indirect` marker the next time you run `go mod tidy`. A plugin that is already in `summer.yaml` is not installed again.

### Required plugins

A plugin's `requires` (from its `plugin.yaml`, as the registry lists it for the chosen release) are installed with it. For each required plugin the application does not have yet, the command picks the newest release that the framework version meets and that is at least the required minimum, then resolves that plugin's own requirements the same way. Required plugins come first in the list and in `summer.yaml`, and all module installs go through a single `go get`, so Go's minimal version selection sees the whole set. Two plugins that ship in the same module are installed from the same release of it.

A required plugin the application already has is not touched, but its version must be at least the minimum: the go.mod require for a module install, the tag `git describe` finds for a plugin checked out as a submodule. When it is older, the command stops and asks you to update that plugin first. A version it cannot read, such as that of a plugin kept in the application's own repository, is accepted with a warning. Requirements that form a cycle in the registry data are reported as an error.

### Confirmation

Before changing anything, the command prints each plugin it is about to add, one line per plugin:

```text
Installing 2 plugins into /srv/acme (framework v0.6.2):
  acme.translate@v0.2.1 (module)
  acme.blog@v0.3.0 (module)
```

Then it asks for confirmation, with "no" as the default. `--yes` skips the question. A run that cannot ask (no terminal, `-n` or `-q`) stops with an error naming `--yes` unless it is given. Declining changes nothing.

### The registry setting

The registry is `https://summercms.io` unless the application's `plugins.registry_url` setting names another one:

```yaml
# config/plugins.yaml
registry_url: https://registry.example.com
```

The environment variable `SUMMER_PLUGINS__REGISTRY_URL` overrides the file. The value must be the final origin, because the client does not follow redirects. An empty value disables registry calls: installs by ID then fail, and the admin's Plugins screen shows only installed plugins. `--offline` disables registry calls for one run.

Every registry call goes through `kiosk.Client`, which uses `fetchguard` with a 10 second timeout and a 4 MiB limit on the answer. Module paths, package paths and versions from the registry are checked (a plain module path, a strict `vX.Y.Z` version) before any `go` command runs.

## Registry API v1

summercms.io publishes the plugins it lists through a read-only JSON API. The marketplace pages, `summer` and the admin's Plugins screen read it. Its base path is `/api/registry/v1` (`kiosk.RegistryAPIPath`), and the `kiosk` module holds its wire types, so every client and the server share one definition of the shape.

| Request | Answer |
|---------|--------|
| `GET /api/registry/v1/plugins?q=&category=` | `{"data": [plugin, ...], "meta": {"total": N}}` (`kiosk.ListResponse`). `q` searches ID, name and description; `category` filters. |
| `GET /api/registry/v1/plugins/{id}` | `{"data": detail}` (`kiosk.DetailResponse`). |
| `GET /api/registry/v1/plugins/{id}/versions` | `{"data": [version, ...]}`, newest first (`kiosk.VersionsResponse`). |
| `POST /api/registry/v1/ingest` | Authenticated with an API token that has the `registry` scope; body `{"repository": "<https URL>"}` (`kiosk.IngestRequest`). Answers 202 with `{"data": {"repository": "...", "queued": true}}` (`kiosk.IngestResponse`). |

A plugin in a list (`kiosk.RegistryPlugin`) has these fields:

| Field | Meaning |
|-------|---------|
| `id`, `name`, `description` | From the latest release's `plugin.yaml`. |
| `module`, `package` | What `go get` and `summer.yaml` take. |
| `repository` | The HTTPS clone URL. |
| `category`, `featured`, `icon_url` | Presentation fields edited on summercms.io. |
| `latest_version`, `latest_framework` | The newest tag and its framework minimum. |
| `updated_at` | When the listing last changed, RFC 3339. |

The detail (`kiosk.RegistryPluginDetail`) adds `readme_markdown`, `readme_html`, `screenshots` (a list of `url` and `caption`) and `requires` of the latest release. A version (`kiosk.RegistryVersion`) has `version`, `framework`, `requires`, `module`, `package`, `commit` and `tagged_at`.

Errors answer with `{"error": {"code": "...", "message": "..."}}` (`kiosk.ErrorResponse`): 404 with `not_found` for an unknown ID, 400 with `invalid_query` for a bad parameter.

Compatibility rules:

- Every answer is an envelope object (`data`, `meta` or `error`), never a bare array.
- Clients ignore fields they do not know, and v1 changes only by adding fields. A change that removes or renames a field needs a `/api/registry/v2` path.
- The GET endpoints need no credentials, allow any origin (CORS) and answer with `Cache-Control: public, max-age=300` and an ETag.
- Versions are strict `vX.Y.Z` tags (`kiosk.ValidVersion`) compared numerically (`kiosk.CompareVersions`). A client picks the release to install with `kiosk.NewestCompatible`: the newest one whose framework minimum the application's framework version satisfies (`kiosk.Satisfies`).