Actions: accept the config input

The idea is to configure GitGitGadget via a `gitgitgadget-config.json`
file that contains the project-specific instance of the `IConfig`
interface, tracked in the `config` branch of a fork of the
`gitgitgadget-workflows` repository, from where it is automatically
synchronized via a GitHub workflow to the repository variable `CONFIG`,
and then passed to all of GitGitGadget's Actions via:

	```yml
	config: '${{ vars.CONFIG }}'
	```

For now, this input is optional, to ease the transition of GitGitGadget;
Eventually, this config will be required, so that several projects can
be served using identical source code in forks of the
`gitgitgadget-github-app` and `gitgitgadget-workflows` repositories.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

handle-new-mails/action.yml

@@ -2,6 +2,9 @@ name: 'Handle new mails'
 description: 'Processes new mails on the Git mailing list'
 author: 'Johannes Schindelin'
 inputs:
+  config:
+    description: 'The GitGitGadget configuration to use (see https://github.com/gitgitgadget/gitgitgadget/blob/HEAD/lib/project-config.ts)'
+    default: '' # sadly, ${{ vars.CONFIG }} does not work, and documentation about what contexts are permissible here is sorely missing
   pr-repo-token:
     description: 'The access token to work on the repository that holds PRs and state'
     required: true

handle-pr-comment/action.yml

@@ -2,6 +2,9 @@ name: 'Handle PR Comment'
 description: 'Handles slash commands such as /submit and /preview'
 author: 'Johannes Schindelin'
 inputs:
+  config:
+    description: 'The GitGitGadget configuration to use (see https://github.com/gitgitgadget/gitgitgadget/blob/HEAD/lib/project-config.ts)'
+    default: '' # sadly, ${{ vars.CONFIG }} does not work, and documentation about what contexts are permissible here is sorely missing
   pr-repo-token:
     description: 'The access token to work on the repository that holds PRs and state'
     required: true

handle-pr-push/action.yml

@@ -2,6 +2,9 @@ name: 'Handle PR Pushes'
 description: 'Handles when a PR was pushed'
 author: 'Johannes Schindelin'
 inputs:
+  config:
+    description: 'The GitGitGadget configuration to use (see https://github.com/gitgitgadget/gitgitgadget/blob/HEAD/lib/project-config.ts)'
+    default: '' # sadly, ${{ vars.CONFIG }} does not work, and documentation about what contexts are permissible here is sorely missing
   pr-repo-token:
     description: 'The access token to work on the repository that holds PRs and state'
     required: true

lib/ci-helper.ts

@@ -53,8 +53,17 @@ export class CIHelper {
         return configFile ? await getExternalConfig(configFile) : getConfig();
     }
 
+    protected static getConfigAsGitHubActionInput(): IConfig | undefined {
+        if (process.env.GITHUB_ACTIONS !== "true") return undefined;
+        const json = core.getInput("config");
+        if (!json) return undefined;
+        const config = JSON.parse(json) as IConfig | undefined;
+        if (typeof config === "object" && config.project !== undefined) return config;
+        return undefined;
+    }
+
     public constructor(workDir: string = "pr-repo.git", config?: IConfig, skipUpdate?: boolean, gggConfigDir = ".") {
-        this.config = config !== undefined ? setConfig(config) : getConfig();
+        this.config = config !== undefined ? setConfig(config) : CIHelper.getConfigAsGitHubActionInput() || getConfig();
         this.gggConfigDir = gggConfigDir;
         this.workDir = workDir;
         this.notes = new GitNotes(workDir);

update-mail-to-commit-notes/action.yml

@@ -2,6 +2,9 @@ name: 'Update the mail <-> commit notes'
 description: 'Updates the mapping between commits and patch emails, stored in the `mail-to-commit` and `commit-to-mail` Git notes refs.'
 author: 'Johannes Schindelin'
 inputs:
+  config:
+    description: 'The GitGitGadget configuration to use (see https://github.com/gitgitgadget/gitgitgadget/blob/HEAD/lib/project-config.ts)'
+    default: '' # sadly, ${{ vars.CONFIG }} does not work, and documentation about what contexts are permissible here is sorely missing
   pr-repo-token:
     description: 'The access token to work on the repository that holds PRs and state'
     required: true

update-prs/action.yml

@@ -2,6 +2,9 @@ name: 'Update the Pull Requests'
 description: 'Updates the Pull Requests in response to upstream commits'
 author: 'Johannes Schindelin'
 inputs:
+  config:
+    description: 'The GitGitGadget configuration to use (see https://github.com/gitgitgadget/gitgitgadget/blob/HEAD/lib/project-config.ts)'
+    default: '' # sadly, ${{ vars.CONFIG }} does not work, and documentation about what contexts are permissible here is sorely missing
   pr-repo-token:
     description: 'The access token to work on the repository that holds PRs and state'
     required: true