feat: add simple container_layer generation (#38)

CHANGELOG.md

@@ -3,5 +3,8 @@
 #### 0.0.0-PLACEHOLDER
 
 * **feat**: Support generating `nodejs_binary` target. The `data` attr will be set to `entry_points` generating rule [#36](https://github.com/Evertz/bzlgen/pull/36)
-* **feat**: Use the buildozer API via the NodeJS bindings rather than invoking directly in a shell on a text file [#35](https://github.com/Evertz/bzlgen/pull/35)
-* **fix**: Handle NodeJS builtins, adding `@types/node` as a dep
+* **feat**: Use the buildozer API via the NodeJS bindings rather than invoking directly in a shell on a text file [#34](https://github.com/Evertz/bzlgen/pull/34)
+* **feat**: Support generating `ts_library` targets for a single file [#35](https://github.com/Evertz/bzlgen/pull/35)
+* **feat**: Support simple generation of `container_layer` targets, adding files at `path` to the `files` attribute [#38](https://github.com/Evertz/bzlgen/pull/38)
+* **feat**: Add `--pattern` flag. When `path` represents a directory, `pattern` is used as a glob for filtering files [#38](https://github.com/Evertz/bzlgen/pull/38)
+* **fix**: Handle NodeJS builtins, adding `@types/node` as a dep [#37](https://github.com/Evertz/bzlgen/pull/37)

README.md

@@ -10,6 +10,7 @@ The generator can create rules for the following and can be extended to provide
 * ng_module
 * ts_library
 * nodejs_binary
+* container_layer
 
 The generator is _somewhat_ flexible in the source structure, but does make a number of assumptions in certain cases.
 It will try and 'best guess' labels from other packages. It's currently not expected to generate a 100% correct and working build file,

src/buildozer.ts

@@ -7,6 +7,7 @@ const DEFAULT_LOAD_SITES = new Map<string, string>([
   ['ts_library', '@npm_bazel_typescript//:index.bzl'],
   ['ng_module', '@npm_angular_bazel//:index.bzl'],
   ['nodejs_binary', '@build_bazel_rules_nodejs//:index.bzl'],
+  ['container_layer', '@io_bazel_rules_docker//container:container.bzl'],
 ]);
 
 /**
@@ -203,11 +204,11 @@ export class Buildozer {
     this.addCommand(`new_load ${from} ${symbols}`, label.withTarget(Buildozer.PKG));
   }
 
-  addAttr(attr: string, value: string[], label: Label) {
+  addAttr(attr: string, value: Array<string | Label>, label: Label) {
     this.addCommand(`add ${attr} ${value.join(' ')}`, label);
   }
 
-  setAttr(attr: string, value: string, label: Label) {
+  setAttr(attr: string, value: string | Label, label: Label) {
     this.addCommand(`set ${attr} "${value}"`, label);
   }
 

src/flags.ts

@@ -12,7 +12,8 @@ export enum GeneratorType {
   NG_BUNDLE = 'ng_bundle',
   SASS = 'sass',
   TS = 'ts',
-  JS_BINARY = 'js_binary'
+  JS_BINARY = 'js_binary',
+  CONTAINER_LAYER = 'container_layer'
 }
 
 function coerceMappingFlag(loads: string[]): Map<string, string> {
@@ -40,6 +41,11 @@ interface CommonFlags {
    */
   path: string;
 
+  /**
+   * A glob pattern that is applied to the files at path when path represents a directory
+   */
+  pattern: string;
+
   /**
    * Remove the existing build file before creating the new one
    */
@@ -262,6 +268,12 @@ export const setupAndParseArgs = (argv: string[], ignorerc = false, strip = 2):
       default: false,
       group: 'Configuration'
     })
+    .option('pattern', {
+      type: 'string',
+      description: 'A glob pattern that is applied to the files at path when path represents a directory',
+      default: false,
+      group: 'Configuration'
+    })
     .option('base_dir', {
       type: 'string',
       description: 'Base dir that is prefixed to \'path\' to form an absolute path',

src/generators/containers/container-layer.generator.ts

@@ -0,0 +1,32 @@
+import { GeneratorType } from '../../flags';
+import { BuildFileGenerator } from '../generator';
+
+export class ContainerLayerGenerator extends BuildFileGenerator {
+
+  async generate(): Promise<void> {
+    const label = this.workspace.getLabelForPath().withTarget('layer');
+
+    this.buildozer.loadRule('container_layer', label);
+    this.buildozer.newRule('container_layer', label);
+
+    const files = [];
+    if (this.workspace.isDirectory()) {
+      let labels = this.workspace.readDirectory()
+        .map(file => this.workspace.getFileLabel(file));
+
+      files.push(...labels);
+    } else {
+      files.push(this.workspace.getFileLabel(this.flags.path));
+    }
+
+    this.buildozer.addAttr('files', files, label);
+  }
+
+  getGeneratorType(): GeneratorType {
+    return GeneratorType.CONTAINER_LAYER;
+  }
+
+  supportsDirectories(): boolean {
+    return true;
+  }
+}

src/main.ts

@@ -9,6 +9,7 @@ import { TsGenerator } from './generators/ts/ts.generator';
 import { debug, fatal, lb, log, warn } from './logger';
 import { snapshot, wrap, TRACER_PATH } from './tracing';
 import { Workspace } from './workspace';
+import { ContainerLayerGenerator } from './generators/containers/container-layer.generator';
 
 function printFlags(flags: Flags) {
   log('Canonicalized Flags:');
@@ -35,6 +36,8 @@ function getGenerator(type: GeneratorType, workspace: Workspace): BuildFileGener
       return new NgGenerator(workspace);
     case GeneratorType.JS_BINARY:
       return new NodejsBinaryGenerator(workspace);
+    case GeneratorType.CONTAINER_LAYER:
+      return new ContainerLayerGenerator(workspace);
     default:
       fatal(`No generator found for type ${type}`);
   }

src/workspace.ts

@@ -10,6 +10,7 @@ import { Buildozer } from './buildozer';
 import { Flags } from './flags';
 import { Label } from './label';
 import { debug, fatal, isDebugEnabled, lb, log, warn } from './logger';
+import { match } from 'minimatch';
 
 export class Workspace {
   private static readonly QUERY_FLAGS = `--output label --order_output=no`;
@@ -68,8 +69,15 @@ export class Workspace {
   readDirectory(): string[] {
     if (!this.isDirectory()) { return []; }
 
-    return readdirSync(this.getAbsolutePath())
-      .map(file => this.resolveRelativeToWorkspace(file));
+    const files = readdirSync(this.getAbsolutePath())
+      .map(file => this.resolveRelativeToWorkspace(file))
+      .filter(file => !file.endsWith(this.flags.build_file_name));
+
+    if (this.flags.pattern) {
+      return match(files, join(this.flags.path, this.flags.pattern));
+    }
+
+    return files;
   }
 
   /**