ios - firebase auth 用户照片 URL 返回 404

几个月来，我一直在 swift 应用程序中使用 firebase 身份验证，但今天突然由于用户照片 URL 指向 404 页面，该应用程序崩溃了。

获取我使用的图片:

let user = FIRAuth.auth()?.currentUser 

userPhoto = user.photoURL?.absoluteString

userPhoto URL 指向损坏的机器人 404 页面，但仅限于一个特定用户。 登录这个有问题的 Google 帐户时，个人资料图片会正确显示。

我尝试退出并重新登录，以及更改帐户的个人资料图片。 有什么想法吗？

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Best Answer-推荐答案

我不知道 IOS/Swift，但我遇到了同样的问题。似乎 Firebase Auth 缓存了 photoURL，我无法弄清楚如何强制刷新，但解决方案是在错误时显示默认图像。在 javascript/HTML 中，它如下所示。注意:有一个 CSS 解决方案使用 :before 和 :after 伪类来显示自定义后备图像，但它有点 hacky 所以我写了这个。我知道这并不快，但也许您可以将其用作为 IOS 编写类似代码的指南。

function returnPhotoURL(){
    return new Promise(function(resolve, reject){
        var img = new Image();
        //if the user does not have a photoURL let's try and get one from gravatar
        if (!firebase.auth().currentUser.photoURL) {
            //first we have to see if user han an email
            if(firebase.auth().currentUser.email){
                //set sign-in-button background image to gravatar url
                img.addEventListener('load', function() {
                    resolve (getGravatar(firebase.auth().currentUser.email, 48));
                }, false);
                img.addEventListener('error', function() {
                    resolve ('//rack.pub/media/fallbackImage.png');
                }, false);            
                img.src = getGravatar(firebase.auth().currentUser.email, 48);
            } else {
                resolve ('//rack.pub/media/fallbackImage.png');
            }
        } else {
            img.addEventListener('load', function() {
                resolve (firebase.auth().currentUser.photoURL);
            }, false);
            img.addEventListener('error', function() {
                resolve ('https://rack.pub/media/fallbackImage.png');
            }, false);      
            img.src = firebase.auth().currentUser.photoURL;
        }
    });
}

function getGravatar(email, size) {
    // MD5 (Message-Digest Algorithm) by WebToolkit
    var MD5 = function(s) {
        function L(k, d) {
            return (k << d) | (k >>> (32 - d))
        }

        function K(G, k) {
            var I, d, F, H, x;
            F = (G & 2147483648);
            H = (k & 2147483648);
            I = (G & 1073741824);
            d = (k & 1073741824);
            x = (G & 1073741823) + (k & 1073741823);
            if (I & d) {
                return (x ^ 2147483648 ^ F ^ H)
            }
            if (I | d) {
                if (x & 1073741824) {
                    return (x ^ 3221225472 ^ F ^ H)
                }
                else {
                    return (x ^ 1073741824 ^ F ^ H)
                }
            }
            else {
                return (x ^ F ^ H)
            }
        }

        function r(d, F, k) {
            return (d & F) | ((~d) & k)
        }

        function q(d, F, k) {
            return (d & k) | (F & (~k))
        }

        function p(d, F, k) {
            return (d ^ F ^ k)
        }

        function n(d, F, k) {
            return (F ^ (d | (~k)))
        }

        function u(G, F, aa, Z, k, H, I) {
            G = K(G, K(K(r(F, aa, Z), k), I));
            return K(L(G, H), F)
        }

        function f(G, F, aa, Z, k, H, I) {
            G = K(G, K(K(q(F, aa, Z), k), I));
            return K(L(G, H), F)
        }

        function D(G, F, aa, Z, k, H, I) {
            G = K(G, K(K(p(F, aa, Z), k), I));
            return K(L(G, H), F)
        }

        function t(G, F, aa, Z, k, H, I) {
            G = K(G, K(K(n(F, aa, Z), k), I));
            return K(L(G, H), F)
        }

        function e(G) {
            var Z;
            var F = G.length;
            var x = F + 8;
            var k = (x - (x % 64)) / 64;
            var I = (k + 1) * 16;
            var aa = Array(I - 1);
            var d = 0;
            var H = 0;
            while (H < F) {
                Z = (H - (H % 4)) / 4;
                d = (H % 4) * 8;
                aa[Z] = (aa[Z] | (G.charCodeAt(H) << d));
                H++
            }
            Z = (H - (H % 4)) / 4;
            d = (H % 4) * 8;
            aa[Z] = aa[Z] | (128 << d);
            aa[I - 2] = F << 3;
            aa[I - 1] = F >>> 29;
            return aa
        }

        function B(x) {
            var k = "",
                F = "",
                G, d;
            for (d = 0; d <= 3; d++) {
                G = (x >>> (d * 8)) & 255;
                F = "0" + G.toString(16);
                k = k + F.substr(F.length - 2, 2)
            }
            return k
        }

        function J(k) {
            k = k.replace(/rn/g, "n");
            var d = "";
            for (var F = 0; F < k.length; F++) {
                var x = k.charCodeAt(F);
                if (x < 128) {
                    d += String.fromCharCode(x)
                }
                else {
                    if ((x > 127) && (x < 2048)) {
                        d += String.fromCharCode((x >> 6) | 192);
                        d += String.fromCharCode((x & 63) | 128)
                    }
                    else {
                        d += String.fromCharCode((x >> 12) | 224);
                        d += String.fromCharCode(((x >> 6) & 63) | 128);
                        d += String.fromCharCode((x & 63) | 128)
                    }
                }
            }
            return d
        }
        var C = Array();
        var P, h, E, v, g, Y, X, W, V;
        var S = 7,
            Q = 12,
            N = 17,
            M = 22;
        var A = 5,
            z = 9,
            y = 14,
            w = 20;
        var o = 4,
            m = 11,
            l = 16,
            j = 23;
        var U = 6,
            T = 10,
            R = 15,
            O = 21;
        s = J(s);
        C = e(s);
        Y = 1732584193;
        X = 4023233417;
        W = 2562383102;
        V = 271733878;
        for (P = 0; P < C.length; P += 16) {
            h = Y;
            E = X;
            v = W;
            g = V;
            Y = u(Y, X, W, V, C[P + 0], S, 3614090360);
            V = u(V, Y, X, W, C[P + 1], Q, 3905402710);
            W = u(W, V, Y, X, C[P + 2], N, 606105819);
            X = u(X, W, V, Y, C[P + 3], M, 3250441966);
            Y = u(Y, X, W, V, C[P + 4], S, 4118548399);
            V = u(V, Y, X, W, C[P + 5], Q, 1200080426);
            W = u(W, V, Y, X, C[P + 6], N, 2821735955);
            X = u(X, W, V, Y, C[P + 7], M, 4249261313);
            Y = u(Y, X, W, V, C[P + 8], S, 1770035416);
            V = u(V, Y, X, W, C[P + 9], Q, 2336552879);
            W = u(W, V, Y, X, C[P + 10], N, 4294925233);
            X = u(X, W, V, Y, C[P + 11], M, 2304563134);
            Y = u(Y, X, W, V, C[P + 12], S, 1804603682);
            V = u(V, Y, X, W, C[P + 13], Q, 4254626195);
            W = u(W, V, Y, X, C[P + 14], N, 2792965006);
            X = u(X, W, V, Y, C[P + 15], M, 1236535329);
            Y = f(Y, X, W, V, C[P + 1], A, 4129170786);
            V = f(V, Y, X, W, C[P + 6], z, 3225465664);
            W = f(W, V, Y, X, C[P + 11], y, 643717713);
            X = f(X, W, V, Y, C[P + 0], w, 3921069994);
            Y = f(Y, X, W, V, C[P + 5], A, 3593408605);
            V = f(V, Y, X, W, C[P + 10], z, 38016083);
            W = f(W, V, Y, X, C[P + 15], y, 3634488961);
            X = f(X, W, V, Y, C[P + 4], w, 3889429448);
            Y = f(Y, X, W, V, C[P + 9], A, 568446438);
            V = f(V, Y, X, W, C[P + 14], z, 3275163606);
            W = f(W, V, Y, X, C[P + 3], y, 4107603335);
            X = f(X, W, V, Y, C[P + 8], w, 1163531501);
            Y = f(Y, X, W, V, C[P + 13], A, 2850285829);
            V = f(V, Y, X, W, C[P + 2], z, 4243563512);
            W = f(W, V, Y, X, C[P + 7], y, 1735328473);
            X = f(X, W, V, Y, C[P + 12], w, 2368359562);
            Y = D(Y, X, W, V, C[P + 5], o, 4294588738);
            V = D(V, Y, X, W, C[P + 8], m, 2272392833);
            W = D(W, V, Y, X, C[P + 11], l, 1839030562);
            X = D(X, W, V, Y, C[P + 14], j, 4259657740);
            Y = D(Y, X, W, V, C[P + 1], o, 2763975236);
            V = D(V, Y, X, W, C[P + 4], m, 1272893353);
            W = D(W, V, Y, X, C[P + 7], l, 4139469664);
            X = D(X, W, V, Y, C[P + 10], j, 3200236656);
            Y = D(Y, X, W, V, C[P + 13], o, 681279174);
            V = D(V, Y, X, W, C[P + 0], m, 3936430074);
            W = D(W, V, Y, X, C[P + 3], l, 3572445317);
            X = D(X, W, V, Y, C[P + 6], j, 76029189);
            Y = D(Y, X, W, V, C[P + 9], o, 3654602809);
            V = D(V, Y, X, W, C[P + 12], m, 3873151461);
            W = D(W, V, Y, X, C[P + 15], l, 530742520);
            X = D(X, W, V, Y, C[P + 2], j, 3299628645);
            Y = t(Y, X, W, V, C[P + 0], U, 4096336452);
            V = t(V, Y, X, W, C[P + 7], T, 1126891415);
            W = t(W, V, Y, X, C[P + 14], R, 2878612391);
            X = t(X, W, V, Y, C[P + 5], O, 4237533241);
            Y = t(Y, X, W, V, C[P + 12], U, 1700485571);
            V = t(V, Y, X, W, C[P + 3], T, 2399980690);
            W = t(W, V, Y, X, C[P + 10], R, 4293915773);
            X = t(X, W, V, Y, C[P + 1], O, 2240044497);
            Y = t(Y, X, W, V, C[P + 8], U, 1873313359);
            V = t(V, Y, X, W, C[P + 15], T, 4264355552);
            W = t(W, V, Y, X, C[P + 6], R, 2734768916);
            X = t(X, W, V, Y, C[P + 13], O, 1309151649);
            Y = t(Y, X, W, V, C[P + 4], U, 4149444226);
            V = t(V, Y, X, W, C[P + 11], T, 3174756917);
            W = t(W, V, Y, X, C[P + 2], R, 718787259);
            X = t(X, W, V, Y, C[P + 9], O, 3951481745);
            Y = K(Y, h);
            X = K(X, E);
            W = K(W, v);
            V = K(V, g)
        }
        var i = B(Y) + B(X) + B(W) + B(V);
        return i.toLowerCase()
    };
    var size = size || 80;
    return 'https://www.gravatar.com/avatar/' + MD5(email) + '.jpg?s=' + size;
}

关于ios - firebase auth 用户照片 URL 返回 404，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/42727333/