[clarity/consistency] rename /explorev2/ -> /explore/ (#2802)

* rename /explorev2/ -> /explore/

* add redirect for existing explorev2 urls

* fix long line

* remove extra line

* fix missed ref in spec

superset/assets/javascripts/explore/components/EmbedCodeButton.jsx

@@ -0,0 +1,122 @@
+import React from 'react';
+import PropTypes from 'prop-types';
+import { Popover, OverlayTrigger } from 'react-bootstrap';
+import CopyToClipboard from './../../components/CopyToClipboard';
+
+const propTypes = {
+  slice: PropTypes.object.isRequired,
+};
+
+export default class EmbedCodeButton extends React.Component {
+  constructor(props) {
+    super(props);
+    this.state = {
+      height: '400',
+      width: '600',
+    };
+    this.handleInputChange = this.handleInputChange.bind(this);
+  }
+
+  handleInputChange(e) {
+    const value = e.currentTarget.value;
+    const name = e.currentTarget.name;
+    const data = {};
+    data[name] = value;
+    this.setState(data);
+  }
+
+  generateEmbedHTML() {
+    const srcLink = (
+      window.location.origin +
+      this.props.slice.data.standalone_endpoint +
+      `&height=${this.state.height}`
+    );
+    return (
+      '<iframe\n' +
+      `  width="${this.state.width}"\n` +
+      `  height="${this.state.height}"\n` +
+      '  seamless\n' +
+      '  frameBorder="0"\n' +
+      '  scrolling="no"\n' +
+      `  src="${srcLink}"\n` +
+      '>\n' +
+      '</iframe>'
+    );
+  }
+
+  renderPopover() {
+    const html = this.generateEmbedHTML();
+    return (
+      <Popover id="embed-code-popover">
+        <div>
+          <div className="row">
+            <div className="col-sm-10">
+              <textarea
+                name="embedCode"
+                value={html}
+                rows="4"
+                readOnly
+                className="form-control input-sm"
+              />
+            </div>
+            <div className="col-sm-2">
+              <CopyToClipboard
+                shouldShowText={false}
+                text={html}
+                copyNode={<i className="fa fa-clipboard" title="Copy to clipboard" />}
+              />
+            </div>
+          </div>
+          <br />
+          <div className="row">
+            <div className="col-md-6 col-sm-12">
+              <div className="form-group">
+                <small>
+                  <label className="control-label" htmlFor="embed-height">Height</label>
+                </small>
+                <input
+                  className="form-control input-sm"
+                  type="text"
+                  defaultValue={this.state.height}
+                  name="height"
+                  onChange={this.handleInputChange}
+                />
+              </div>
+            </div>
+            <div className="col-md-6 col-sm-12">
+              <div className="form-group">
+                <small>
+                  <label className="control-label" htmlFor="embed-width">Width</label>
+                </small>
+                <input
+                  className="form-control input-sm"
+                  type="text"
+                  defaultValue={this.state.width}
+                  name="width"
+                  onChange={this.handleInputChange}
+                  id="embed-width"
+                />
+              </div>
+            </div>
+          </div>
+        </div>
+      </Popover>
+    );
+  }
+  render() {
+    return (
+      <OverlayTrigger
+        trigger="click"
+        rootClose
+        placement="left"
+        overlay={this.renderPopover()}
+      >
+        <span className="btn btn-default btn-sm">
+          <i className="fa fa-code" />&nbsp;
+        </span>
+      </OverlayTrigger>
+    );
+  }
+}
+
+EmbedCodeButton.propTypes = propTypes;