fs/lib/WriterCollection.js

  1. import AbstractReaderWriter from "./AbstractReaderWriter.js";
  2. import ReaderCollection from "./ReaderCollection.js";
  3. import escapeStringRegExp from "escape-string-regexp";
  5. /**
  6.  * Resource Locator WriterCollection
  7.  *
  8.  * @public
  9.  * @class
  10.  * @alias @ui5/fs/WriterCollection
  11.  * @extends @ui5/fs/AbstractReaderWriter
  12.  */
  13. class WriterCollection extends AbstractReaderWriter {
  14. 	/**
  15. 	 * The constructor.
  16. 	 *
  17. 	 * @param {object} parameters Parameters
  18. 	 * @param {string} parameters.name The collection name
  19. 	 * @param {object.<string, @ui5/fs/AbstractReaderWriter>} parameters.writerMapping
  20. 	 * 	Mapping of virtual base paths to writers. Path are matched greedy
  21. 	 *
  22. 	 * @example
  23. 	 * new WriterCollection({
  24. 	 *     name: "Writer Collection",
  25. 	 *     writerMapping: {
  26. 	 *	       "/": writerA,
  27. 	 *	       "/my/path/": writerB,
  28. 	 *     }
  29. 	 * });
  30. 	 */
  31. 	constructor({name, writerMapping}) {
  32. 		super(name);
  34. 		if (!writerMapping) {
  35. 			throw new Error(`Cannot create WriterCollection ${this._name}: Missing parameter 'writerMapping'`);
  36. 		}
  37. 		const basePaths = Object.keys(writerMapping);
  38. 		if (!basePaths.length) {
  39. 			throw new Error(`Cannot create WriterCollection ${this._name}: Empty parameter 'writerMapping'`);
  40. 		}
  42. 		// Create a regular expression (which is greedy by nature) from all paths to easily
  43. 		//	find the correct writer for any given resource path
  44. 		this._basePathRegex = basePaths.sort().reduce((regex, basePath, idx) => {
  45. 			// Validate base path
  46. 			if (!basePath) {
  47. 				throw new Error(`Empty path in path mapping of WriterCollection ${this._name}`);
  48. 			}
  49. 			if (!basePath.startsWith("/")) {
  50. 				throw new Error(
  51. 					`Missing leading slash in path mapping '${basePath}' of WriterCollection ${this._name}`);
  52. 			}
  53. 			if (!basePath.endsWith("/")) {
  54. 				throw new Error(
  55. 					`Missing trailing slash in path mapping '${basePath}' of WriterCollection ${this._name}`);
  56. 			}
  58. 			return `${regex}(?:${escapeStringRegExp(basePath)})??`;
  59. 		}, "^(") + ")+.*?$";
  61. 		this._writerMapping = writerMapping;
  62. 		this._readerCollection = new ReaderCollection({
  63. 			name: `Reader collection of writer collection '${this._name}'`,
  64. 			readers: Object.values(writerMapping)
  65. 		});
  66. 	}
  68. 	/**
  69. 	 * Locates resources by glob.
  70. 	 *
  71. 	 * @private
  72. 	 * @param {string|string[]} pattern glob pattern as string or an array of
  73. 	 *         glob patterns for virtual directory structure
  74. 	 * @param {object} options glob options
  75. 	 * @param {@ui5/fs/tracing.Trace} trace Trace instance
  76. 	 * @returns {Promise<@ui5/fs/Resource[]>} Promise resolving to list of resources
  77. 	 */
  78. 	_byGlob(pattern, options, trace) {
  79. 		return this._readerCollection._byGlob(pattern, options, trace);
  80. 	}
  82. 	/**
  83. 	 * Locates resources by path.
  84. 	 *
  85. 	 * @private
  86. 	 * @param {string} virPath Virtual path
  87. 	 * @param {object} options Options
  88. 	 * @param {@ui5/fs/tracing.Trace} trace Trace instance
  89. 	 * @returns {Promise<@ui5/fs/Resource>} Promise resolving to a single resource
  90. 	 */
  91. 	_byPath(virPath, options, trace) {
  92. 		return this._readerCollection._byPath(virPath, options, trace);
  93. 	}
  95. 	/**
  96. 	 * Writes the content of a resource to a path.
  97. 	 *
  98. 	 * @private
  99. 	 * @param {@ui5/fs/Resource} resource The Resource to write
  100. 	 * @param {object} [options] Write options, see above
  101. 	 * @returns {Promise<undefined>} Promise resolving once data has been written
  102. 	 */
  103. 	_write(resource, options) {
  104. 		const resourcePath = resource.getPath();
  106. 		const basePathMatch = resourcePath.match(this._basePathRegex);
  107. 		if (!basePathMatch || basePathMatch.length < 2) {
  108. 			throw new Error(
  109. 				`Failed to find a writer for resource with path ${resourcePath} in WriterCollection ${this._name}. ` +
  110. 				`Base paths handled by this collection are: ${Object.keys(this._writerMapping).join(", ")}`);
  111. 		}
  112. 		const writer = this._writerMapping[basePathMatch[1]];
  113. 		return writer._write(resource, options);
  114. 	}
  115. }
  117. export default WriterCollection;