Fix grecaptcha throwing useless error sometimes

src/components/views/auth/CaptchaForm.tsx

@@ -0,0 +1,148 @@
+/*
+Copyright 2015, 2016 OpenMarket Ltd
+
+Licensed 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.
+*/
+
+import React, { createRef } from 'react';
+import { _t } from '../../../languageHandler';
+import CountlyAnalytics from "../../../CountlyAnalytics";
+import { replaceableComponent } from "../../../utils/replaceableComponent";
+
+const DIV_ID = 'mx_recaptcha';
+
+interface ICaptchaFormProps {
+    sitePublicKey: string
+    onCaptchaResponse: () => void
+}
+
+interface ICaptchaFormState {
+    errorText: string | null
+
+}
+
+/**
+ * A pure UI component which displays a captcha form.
+ */
+@replaceableComponent("views.auth.CaptchaForm")
+export default class CaptchaForm extends React.Component<ICaptchaFormProps, ICaptchaFormState> {
+    static defaultProps = {
+        onCaptchaResponse: () => { },
+    };
+
+    private _captchaWidgetId: string | null = null;
+    private _recaptchaContainer: React.RefObject<HTMLDivElement> = createRef();
+
+    state = {
+        errorText: null,
+    };
+
+    constructor(props: ICaptchaFormProps) {
+        super(props);
+
+        CountlyAnalytics.instance.track("onboarding_grecaptcha_begin");
+    }
+
+    componentDidMount() {
+        // Just putting a script tag into the returned jsx doesn't work, annoyingly,
+        // so we do this instead.
+        if (this.isRecaptchaReady()) {
+            // already loaded
+            this._onCaptchaLoaded();
+        } else {
+            console.log("Loading recaptcha script...");
+            window.mxOnRecaptchaLoaded = () => { this._onCaptchaLoaded(); };
+            const scriptTag = document.createElement('script');
+            scriptTag.setAttribute(
+                'src', `https://www.recaptcha.net/recaptcha/api.js?onload=mxOnRecaptchaLoaded&render=explicit`,
+            );
+            this._recaptchaContainer.current.appendChild(scriptTag);
+        }
+    }
+
+    componentWillUnmount() {
+        this._resetRecaptcha();
+    }
+
+    // Borrowed directly from: https://github.com/codeep/react-recaptcha-google/commit/e118fa5670fa268426969323b2e7fe77698376ba
+    private isRecaptchaReady() {
+        return typeof window !== "undefined" &&
+            typeof global.grecaptcha !== "undefined" &&
+            typeof global.grecaptcha.render === 'function';
+    }
+
+    private _renderRecaptcha(divId) {
+        if (!this.isRecaptchaReady()) {
+            console.error("grecaptcha not loaded!");
+            throw new Error("Recaptcha did not load successfully");
+        }
+
+        const publicKey = this.props.sitePublicKey;
+        if (!publicKey) {
+            console.error("No public key for recaptcha!");
+            throw new Error(
+                "This server has not supplied enough information for Recaptcha "
+                + "authentication");
+        }
+
+        console.info("Rendering to %s", divId);
+        this._captchaWidgetId = global.grecaptcha.render(divId, {
+            sitekey: publicKey,
+            callback: this.props.onCaptchaResponse,
+        });
+    }
+
+    private _resetRecaptcha() {
+        if (this._captchaWidgetId !== null) {
+            global.grecaptcha.reset(this._captchaWidgetId);
+        }
+    }
+
+    private _onCaptchaLoaded() {
+        console.log("Loaded recaptcha script.");
+        try {
+            this._renderRecaptcha(DIV_ID);
+            // clear error if re-rendered
+            this.setState({
+                errorText: null,
+            });
+            CountlyAnalytics.instance.track("onboarding_grecaptcha_loaded");
+        } catch (e) {
+            this.setState({
+                errorText: e.toString(),
+            });
+            CountlyAnalytics.instance.track("onboarding_grecaptcha_error", { error: e.toString() });
+        }
+    }
+
+    render() {
+        let error = null;
+        if (this.state.errorText) {
+            error = (
+                <div className="error">
+                    {this.state.errorText}
+                </div>
+            );
+        }
+
+        return (
+            <div ref={this._recaptchaContainer}>
+                <p>{_t(
+                    "This homeserver would like to make sure you are not a robot.",
+                )}</p>
+                <div id={DIV_ID} />
+                {error}
+            </div>
+        );
+    }
+}