tag-names output to return tag names without image base name

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

README.md

@@ -314,6 +314,7 @@ The following outputs are available:
 |-------------------------|--------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------|
 | `version`               | String | Docker image version                                                                                                                                            |
 | `tags`                  | String | Docker tags                                                                                                                                                     |
+| `tag-names`             | String | Docker tag names without image base name                                                                                                                        |
 | `labels`                | String | Docker labels                                                                                                                                                   |
 | `annotations`           | String | [Annotations](https://github.com/moby/buildkit/blob/master/docs/annotations.md)                                                                                 |
 | `json`                  | String | JSON output of tags and labels                                                                                                                                  |

__tests__/meta.test.ts

@@ -3936,6 +3936,12 @@ describe('json', () => {
           "user/app:custom",
           "user/app:tags"
         ],
+        "tag-names": [
+          "dev",
+          "my",
+          "custom",
+          "tags"
+        ],
         "labels": {
           "foo": "",
           "org.opencontainers.image.created": "2020-01-10T00:30:00.000Z",
@@ -3974,6 +3980,10 @@ describe('json', () => {
           "user/app:dev",
           "user/app:my",
         ],
+        "tag-names": [
+          "dev",
+          "my",
+        ],
         "labels": {
           "org.opencontainers.image.created": "2020-01-10T00:30:00.000Z",
           "org.opencontainers.image.description": "This your first repo!",
@@ -4017,6 +4027,13 @@ describe('json', () => {
           "user/app:tags",
           "user/app:latest"
         ],
+        "tag-names": [
+          "release1",
+          "my",
+          "custom",
+          "tags",
+          "latest"
+        ],
         "labels": {
           "org.opencontainers.image.created": "2020-01-10T00:30:00.000Z",
           "org.opencontainers.image.description": "This your first repo!",
@@ -4061,6 +4078,12 @@ describe('json', () => {
           "user/app:custom",
           "user/app:tags"
         ],
+        "tag-names": [
+          "20200110",
+          "my",
+          "custom",
+          "tags"
+        ],
         "labels": {
           "org.opencontainers.image.created": "2020-01-10T00:30:00.000Z",
           "org.opencontainers.image.description": "This your first repo!",
@@ -4114,6 +4137,15 @@ describe('json', () => {
           "ghcr.io/user/app:tags",
           "ghcr.io/user/app:latest"
         ],
+        "tag-names": [
+          "1.1.1",
+          "1.1",
+          "1",
+          "my",
+          "custom",
+          "tags",
+          "latest",
+        ],
         "labels": {
           "org.opencontainers.image.created": "2020-01-10T00:30:00.000Z",
           "org.opencontainers.image.description": "This your first repo!",
@@ -4156,6 +4188,11 @@ describe('json', () => {
           "ghcr.io/user/app:custom",
           "ghcr.io/user/app:tags"
         ],
+        "tag-names": [
+          "my",
+          "custom",
+          "tags",
+        ],
         "labels": {
           "org.opencontainers.image.created": "2020-01-10T00:30:00.000Z",
           "org.opencontainers.image.description": "This your first repo!",
@@ -4196,6 +4233,10 @@ describe('json', () => {
           "org/app:v1.1.1",
           "org/app:latest"
         ],
+        "tag-names": [
+          "v1.1.1",
+          "latest"
+        ],
         "labels": {
           "maintainer": "CrazyMax",
           "org.opencontainers.image.created": "2020-01-10T00:30:00.000Z",

action.yml

@@ -48,6 +48,8 @@ outputs:
     description: 'Generated Docker image version'
   tags:
     description: 'Generated Docker tags'
+  tag-names:
+    description: 'Generated Docker tag names without image base name'
   labels:
     description: 'Generated Docker labels'
   annotations:

src/main.ts

@@ -47,7 +47,7 @@ actionsToolkit.run(
     setOutput('version', version.main || '');
 
     // Docker tags
-    const tags: Array<string> = meta.getTags();
+    const tags = meta.getTags();
     if (tags.length == 0) {
       core.warning('No Docker tag has been generated. Check tags input.');
     } else {
@@ -58,6 +58,7 @@ actionsToolkit.run(
       });
     }
     setOutput('tags', tags.join(inputs.sepTags));
+    setOutput('tag-names', meta.getTags(true).join(inputs.sepTags));
 
     // Docker labels
     const labels: Array<string> = meta.getLabels();

src/meta.ts

@@ -494,33 +494,37 @@ export class Meta {
     return images;
   }
 
-  public getTags(): Array<string> {
+  public getTags(namesOnly?: boolean): Array<string> {
     if (!this.version.main) {
       return [];
     }
-
+    if (namesOnly) {
-    const generateTags = (imageName: string, version: string): Array<string> => {
+      return this.generateTags(this.version.main);
-      const tags: Array<string> = [];
+    }
-      const prefix = imageName !== '' ? `${imageName}:` : '';
-      tags.push(`${prefix}${version}`);
-      for (const partial of this.version.partial) {
-        tags.push(`${prefix}${partial}`);
-      }
-      if (this.version.latest) {
-        const latestTag = `${this.flavor.prefixLatest ? this.flavor.prefix : ''}latest${this.flavor.suffixLatest ? this.flavor.suffix : ''}`;
-        tags.push(`${prefix}${Meta.sanitizeTag(latestTag)}`);
-      }
-      return tags;
-    };
 
     const tags: Array<string> = [];
     const images = this.getImageNames();
     if (images.length > 0) {
       for (const imageName of images) {
-        tags.push(...generateTags(imageName, this.version.main));
+        tags.push(...this.generateTags(this.version.main, imageName));
       }
     } else {
-      tags.push(...generateTags('', this.version.main));
+      tags.push(...this.generateTags(this.version.main));
+    }
+
+    return tags;
+  }
+
+  private generateTags(version: string, imageName?: string): Array<string> {
+    const tags: Array<string> = [];
+    const prefix = imageName ? `${imageName}:` : '';
+    tags.push(`${prefix}${version}`);
+    for (const partial of this.version.partial) {
+      tags.push(`${prefix}${partial}`);
+    }
+    if (this.version.latest) {
+      const latestTag = `${this.flavor.prefixLatest ? this.flavor.prefix : ''}latest${this.flavor.suffixLatest ? this.flavor.suffix : ''}`;
+      tags.push(`${prefix}${Meta.sanitizeTag(latestTag)}`);
     }
     return tags;
   }
@@ -568,6 +572,7 @@ export class Meta {
     }
     return {
       tags: this.getTags(),
+      'tag-names': this.getTags(true),
       labels: this.getLabels().reduce((res, label) => {
         const matches = label.match(/([^=]*)=(.*)/);
         if (!matches) {