Last active
June 19, 2019 00:01
-
-
Save mattlockyer/9dbbed5f50a9c972e664b4ed81235ab5 to your computer and use it in GitHub Desktop.
Facebook Login for Web with Using Go Server. Token returned from FB Login button on client. Client makes POST request. FB API called with GET request. Token Validated. Reponsd to client with error / JSON.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| <!doctype html> | |
| <html lang="en"> | |
| <head> | |
| <meta charset="utf-8"> | |
| <meta name="viewport" content="width=device-width, initial-scale=1"> | |
| <title>Facebook Login Example</title> | |
| <meta name="description" content="Facebook Login Example"> | |
| <meta name="author" content="Matt Lockyer"> | |
| </head> | |
| <body> | |
| <div class="fb-login-button" data-width="" data-size="large" data-button-type="continue_with" data-auto-logout-link="false" data-use-continue-as="false"></div> | |
| <div id="fb-root"></div> | |
| <script crossorigin="anonymous" src="https://connect.facebook.net/en_US/sdk.js#xfbml=1&version=v3.3&appId=xxxxxxxxxxxxxxx&autoLogAppEvents=1"></script> | |
| <script> | |
| window.onload = () => { | |
| FB.getLoginStatus(async (response) => { | |
| if (response.status === 'connected') { | |
| const token = response.authResponse.accessToken | |
| console.log(token) | |
| const res = await fetch('http://localhost:8080/validate', { | |
| method: 'POST', mode: "cors", | |
| body: JSON.stringify({ token }) | |
| }).then((res) => res.json()) | |
| console.log(res) | |
| } | |
| }) | |
| } | |
| </script> | |
| </body> | |
| </html> |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| package main | |
| import ( | |
| "encoding/json" | |
| "net/http" | |
| ) | |
| /******************************** | |
| Accept TokenPayload from the client with only token field provided | |
| Validate client token with fb api | |
| Repond with TokenPayload fully or partially filled | |
| ********************************/ | |
| var access_token string = "xxxxxxxxxxxxxxx|xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" | |
| type TokenPayload struct { | |
| UserId string `json:"user_id"` | |
| Token string `json:"token"` | |
| Message string `json:"message"` | |
| } | |
| type msi = map[string]interface{} | |
| func validate(w http.ResponseWriter, r *http.Request) { | |
| // Read body | |
| defer r.Body.Close() | |
| // Unmarshal | |
| var payload TokenPayload | |
| err := json.NewDecoder(r.Body).Decode(&payload) | |
| if err != nil { | |
| http.Error(w, err.Error(), 500) | |
| return | |
| } | |
| // Fetch response for payload.Token | |
| r2, err := http.Get("https://graph.facebook.com/v3.3/debug_token?input_token=" + | |
| payload.Token + "&access_token=" + access_token) | |
| if err != nil { | |
| http.Error(w, err.Error(), 500) | |
| return | |
| } | |
| defer r2.Body.Close() | |
| var r3 msi | |
| err = json.NewDecoder(r2.Body).Decode(&r3) | |
| if err != nil { | |
| http.Error(w, err.Error(), 500) | |
| return | |
| } | |
| // FB error will respond with object { "error": ... } and the below will panic | |
| if r3["error"] != nil { | |
| http.Error(w, err.Error(), 500) | |
| return | |
| } | |
| fbData := r3["data"].(msi) | |
| if (!fbData["is_valid"].(bool)) { | |
| payload.Message = "FB token not valid" | |
| } else { | |
| payload.Message = "FB token is valid" | |
| payload.UserId = fbData["user_id"].(string) | |
| } | |
| // Return output | |
| output, err := json.Marshal(payload) | |
| if err != nil { | |
| http.Error(w, err.Error(), 500) | |
| return | |
| } | |
| w.Header().Set("content-type", "application/json") | |
| w.Write(output) | |
| } | |
| func index(w http.ResponseWriter, r *http.Request) { | |
| } | |
| func main() { | |
| http.Handle("/", http.FileServer(http.Dir("./static"))) | |
| http.HandleFunc("/validate", validate) | |
| println("Listening on 8080") | |
| http.ListenAndServe(":8080", nil) | |
| } | |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment