feat(plugin): Add new Option to NOT push the version tag

.dockerignore

@@ -0,0 +1 @@
+**

.gitignore

@@ -7,3 +7,5 @@ node_modules
 dist
 
 *.log
+
+develop.ts

Dockerfile

@@ -0,0 +1,2 @@
+FROM scratch
+ARG TEST

README.md

@@ -7,68 +7,52 @@
 
 A [semantic-release](https://github.com/semantic-release/semantic-release) plugin to use semantic versioning for docker images.
 
-## verifyConditions
-
-verifies that environment variables for authentication via username and password are set.
-It uses a registry server provided via config or environment variable (preferred) or defaults to docker hub if none is given.
-It also verifies that the credentials are correct by logging in to the given registry.
-
-## prepare
-
-tags the specified image with the version number determined by semantic-release and additional tags provided in the configuration.
-In addition it supports specifying a complete image name (CIN) via configuration settings according to the canonical format specified by docker:
-
-`[registryhostname[:port]/][username/]imagename[:tag]`
-
-## publish
+## Configuration
 
-pushes the tagged images to the registry.
+### Installation
 
-## Configuration
+`npm i --save @iteratec/semantic-release-docker`
 
-### docker registry authentication
+### Docker registry authentication
 
 The `docker registry` authentication is **required** and can be set via environment variables.
 
 ### Environment variables
 
 | Variable                 | Description                                                                               |
-|--------------------------|-------------------------------------------------------------------------------------------|
+| ------------------------ | ----------------------------------------------------------------------------------------- |
 | DOCKER_REGISTRY_URL      | The hostname and port used by the desired docker registry. Leave blank to use docker hub. |
 | DOCKER_REGISTRY_USER     | The user name to authenticate with at the registry.                                       |
 | DOCKER_REGISTRY_PASSWORD | The password used for authentication at the registry.                                     |
 
-### Options
-
-| Option         | Description                                                                                |
-|----------------|--------------------------------------------------------------------------------------------|
-| additionalTags | _Optional_. An array of strings allowing to specify additional tags to apply to the image. |
-| imageName      | **_Required_** The name of the image to release.                                           |
-| registryUrl    | _Optional_. The hostname and port used by the the registry in format `hostname[:port]`. Omit the port if the registry uses the default port |
-| repositoryName | _Optional_. The name of the repository in the registry, e.g. username on docker hub        | 
-
 ### Usage
 
-full configuration:
-``` json
+#### Full configuration
+
+```json
 {
   "verifyConfig": ["@iteratec/semantic-release-docker"],
-  "prepare": {
-    "path": "@iteratec/semantic-release-docker",
-    "additionalTags": ["test", "demo"],
-    "imageName": "my-image",
-    "registryUrl": "my-private-registry:5678",
-    "respositoryName": "my-repository"
-  },
+  "prepare": [
+    {
+      "path": "@iteratec/semantic-release-docker",
+      "additionalTags": ["test", "demo"],
+      "imageName": "my-image",
+      "registryUrl": "my-private-registry:5678",
+      "respositoryName": "my-repository",
+      "pushVersionTag": true
+    }
+  ],
   "publish": {
     "path": "@iteratec/semantic-release-docker"
   }
 }
 ```
-results in `my-private-registry:5678/my-repository/my-image` with tags `test`, `demo` and the `<semver>` determined by `semantic-release`.
 
-minimum configuration:
-``` json
+Results in `my-private-registry:5678/my-repository/my-image` with tags `test`, `demo` and the `<semver>` determined by `semantic-release`.
+
+#### Minimum configuration
+
+```json
 {
   "verifyConfig": ["@iteratec/semantic-release-docker"],
   "prepare": {
@@ -80,4 +64,97 @@ minimum configuration:
   }
 }
 ```
-results in `my-image:<semver>`
+
+Results in `my-image:<semver>`.
+
+### Options
+
+| Option         | Description                                                                                                                                 |
+| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------- |
+| additionalTags | _Optional_. An array of strings allowing to specify additional tags to apply to the image.                                                  |
+| imageName      | **_Required_** The name of the image to release.                                                                                            |
+| registryUrl    | _Optional_. The hostname and port used by the the registry in format `hostname[:port]`. Omit the port if the registry uses the default port |
+| repositoryName | _Optional_. The name of the repository in the registry, e.g. username on docker hub                                                         |
+| pushVersionTag | _Optional_. Whether the semantic release tag, determined by the version, should be pushed. Default is `true`.                               |
+
+## Steps
+
+### verifyConditions
+
+It uses a registry server provided via config or environment variable (preferred) or defaults to docker hub if none is given.
+
+1. Verifies that environment variables for authentication via username and password are set.
+2. It also verifies that the credentials are correct by logging in to the given registry.
+
+### prepare
+
+Tags the specified image with the version number determined by semantic-release and additional tags provided in the configuration.
+In addition it supports specifying a complete image name (CIN) via configuration settings according to the canonical format specified by docker:
+
+`[registryhostname[:port]/][username/]imagename[:tag]`
+
+### publish
+
+Pushes the tagged images to the registry.
+
+## Contribute
+
+### Develop
+
+1. Create a develop.ts file in the root of this Git-Repository and copy this:
+
+```typescript
+import { SemanticReleaseConfig, SemanticReleaseContext } from 'semantic-release';
+import { prepare, publish, verifyConditions } from './src';
+import { DockerPluginConfig } from './src/models';
+
+process.env.DOCKER_REGISTRY_USER = '<Your Docker Registry User>';
+process.env.DOCKER_REGISTRY_PASSWORD = '<Your Docker Registry Password>';
+
+const config: SemanticReleaseConfig = {
+  branch: '',
+  noCi: true,
+  repositoryUrl: '',
+  tagFormat: ''
+};
+const context: SemanticReleaseContext = {
+  logger: {
+    // tslint:disable-next-line:no-empty
+    log: (message: string) => {}
+  },
+  options: {
+    branch: '',
+    noCi: true,
+    prepare: [
+      {
+        additionalTags: ['latest'],
+        imageName: 'testimage',
+        repositoryName: '<your test repository>',
+        path: '@iteratec/semantic-release-docker'
+      } as DockerPluginConfig,
+      {
+        additionalTags: ['latest'],
+        imageName: 'testimage1',
+        repositoryName: '<your test repository>',
+        path: '@iteratec/semantic-release-docker'
+      } as DockerPluginConfig
+    ],
+    repositoryUrl: '',
+    tagFormat: ''
+  },
+  nextRelease: {
+    version: '1.0.3',
+    gitHead: '45jh345g',
+    gitTag: 'v1.0.3',
+    notes: 'Nothing special'
+  }
+};
+context.logger.log = (string: string) => {
+  console.log(string);
+};
+verifyConditions(config, context);
+prepare(config, context);
+publish(config, context);
+```
+
+2.  Simply run the "Debug" VS Code Task