feat: Add frontend interpreter framework

zeppelin-web/src/app/frontend-interpreter/.npmignore

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+*.html

zeppelin-web/src/app/frontend-interpreter/frontend-interpreter-framework.js

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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*eslint-disable no-unused-vars */
+import {
+  DefaultDisplayType,
+  FrontendInterpreterResult,
+} from './frontend-interpreter-result';
+/*eslint-enable no-unused-vars */
+
+export class AbstractFrontendInterpreter {
+  constructor(magic, displayType) {
+    this.magic = magic;
+    this.displayType = displayType;
+  }
+
+  /**
+   * @param paragraphText which includes magic
+   * @returns {string} if magic exists, otherwise return undefined
+   */
+  static extractMagic(allParagraphText) {
+  const intpNameRegexp = /^\s*%(\S+)\s*/g;
+  try {
+    let match = intpNameRegexp.exec(allParagraphText);
+    if (match) { return `%${match[1].trim()}`; }
+  } catch (error) {
+    // failed to parse, ignore
+  }
+
+  return undefined;
+}
+
+  static useInterpret(interpreter) {
+    return (interpreter.__proto__.hasOwnProperty('interpret'));
+  }
+
+  static useDisplay(interpreter) {
+    return (interpreter.__proto__.hasOwnProperty('display'));
+  }
+
+  /**
+   * Consumes text and return multiple interpreter results.
+   * This method should handle error properly to provide precise error message.
+   *
+   * @param paragraphText {string} which doesn't include magic
+   * @return {Array<FrontendInterpreterResult>}
+   */
+  interpret(paragraphText) {
+    /** implement this if you want to add a frontend interpreter */
+  }
+
+  /**
+   * Consumes text and return a single interpreter result.
+   * This method should handle error properly to provide precise error message.
+   *
+   * Currently, `display` only allows DefaultDisplayType
+   * as a type of result to avoid to recursive evaluation of display results.
+   *
+   * @param paragraphText {string}
+   * @return {FrontendInterpreterResult}
+   */
+  display(paragraphText) {
+    /** implement this if you want to add a display system */
+  }
+
+  /**
+   * return magic for this frontend interpreter.
+   * (e.g `%flowchart`)
+   * @return {string}
+   */
+  getMagic() {
+    return this.magic;
+  }
+
+  /**
+   * return display type for this frontend interpreter.
+   * (e.g `DefaultDisplayType.TEXT`)
+   * @return {string}
+   */
+  getDisplayType() {
+    return this.displayType;
+  }
+}

zeppelin-web/src/app/frontend-interpreter/frontend-interpreter-result.js

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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+export const DefaultDisplayType = {
+  ELEMENT: 'ELEMENT',
+  TABLE: 'TABLE',
+  HTML: 'HTML',
+  ANGULAR: 'ANGULAR',
+  TEXT: 'TEXT',
+};
+
+export class FrontendInterpreterResult {
+  constructor(resultDisplayType, resultDataGenerator) {
+    /**
+     * backend interpreter uses `data` and `type` as field names.
+     * let's use the same field to keep consistency.
+     */
+    this.type = resultDisplayType;
+    this.data = resultDataGenerator;
+  }
+
+  static isFunctionGenerator(generator) {
+    return (generator && typeof generator === 'function');
+  }
+
+  static isPromiseGenerator(generator) {
+    return (generator && typeof generator.then === 'function');
+  }
+
+  static isObjectGenerator(generator) {
+    return (
+      !FrontendInterpreterResult.isFunctionGenerator(generator) &&
+      !FrontendInterpreterResult.isPromiseGenerator(generator));
+  }
+
+  /**
+   * @returns {string} display type for this frontend interpreter result.
+   */
+  getType() {
+    return this.type;
+  }
+
+  /**
+   * generator (`data`) can be promise, function or just object
+   * - if data is an object, it will be used directly.
+   * - if data is a function, it will be called with DOM element id
+   *   where the final output is rendered.
+   * - if data is a promise, the post processing logic
+   *   will be called in `then()` of this promise.
+   * @returns {*} `data` which can be object, function or promise.
+   */
+  getData() {
+    return this.data;
+  }
+}

zeppelin-web/src/app/frontend-interpreter/index.js

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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+export {
+  DefaultDisplayType,
+  FrontendInterpreterResult,
+} from './frontend-interpreter-result';
+
+export {
+  AbstractFrontendInterpreter
+} from './frontend-interpreter-framework';

zeppelin-web/src/app/frontend-interpreter/package.json

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+{
+  "name": "zeppelin-frontend-interpreter",
+  "description": "Frontend Interpreter API",
+  "version": "0.7.0-SNAPSHOT",
+  "main": "index",
+  "dependencies": {
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/apache/zeppelin"
+  },
+  "license": "Apache-2.0"
+}