Google and Facebook have provided step by step details to integrate with their login and validate the token with backed.
You can follow the below steps for details.
Google :
https://developers.google.com/identity/sign-in/web/sign-in
https://developers.google.com/identity/sign-in/web/backend-auth
Make a rest call https://www.googleapis.com/oauth2/v3/tokeninfo?id_token= to integrate and validate the token with backed, pass the accessToken which recived on successfully logged in with frontend google web plugin and store the info or validate with your DB.
public String getGoogleTokenInfo(String accessToken) throws BadRequestException {
log.debug("Calling Google API to get token info");
RestTemplate restTemplate = new RestTemplate();
String googleResponse = null;
try {
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
UriComponentsBuilder uriBuilder = UriComponentsBuilder.fromUriString("https://www.googleapis.com/oauth2/v3/tokeninfo").queryParam("id_token", accessToken);
log.debug("google login uri {}", uriBuilder.toUriString());
googleResponse = restTemplate.getForObject(uriBuilder.toUriString(), String.class);
log.info("Gmail user authenticated successfully, details [{}]", googleResponse.toString());
} catch (HttpClientErrorException e) {
log.error("Not able to authenticate from Google");
try {
JsonNode error = new ObjectMapper().readValue(e.getResponseBodyAsString(), JsonNode.class);
log.error(error.toString());
throw new BadRequestException("Invalid access token");
} catch (IOException mappingExp) {
throw new BadRequestException("Invalid user");
}
} catch (Exception exp) {
log.error("User is not authorized to login into system", exp);
throw new BadRequestException("Invalid user");
}
return googleResponse;
}
Facebook:
https://developers.facebook.com/docs/facebook-login/web#example
Make a rest call https://graph.facebook.com/me?access_token= from backed by passing the accessToken which recived on successfully logged in with facebook frontend web plugin to validate the token and get profile info and store the info to your DB.
public String getFacebookProfileInfo(final String accessToken) throws BadRequestException {
log.debug("Calling Facebook API to validate and get profile info");
RestTemplate restTemplate = new RestTemplate();
String facebook = null;
// field names which will be retrieved from facebook
final String fields = "id,email,first_name,last_name";
try {
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
UriComponentsBuilder uriBuilder = UriComponentsBuilder.fromUriString("https://graph.facebook.com/me")
.queryParam("access_token", accessToken).queryParam("fields", fields);
log.debug("Facebook profile uri {}", uriBuilder.toUriString());
facebook = restTemplate.getForObject(uriBuilder.toUriString(), String.class);
log.info("Facebook user authenticated and profile fetched successfully, details [{}]", facebook.toString());
} catch (HttpClientErrorException e) {
log.error("Not able to authenticate from Facebook");
throw new BadRequestException("Invalid access token");
} catch (Exception exp) {
log.error("User is not authorized to login into system", exp);
throw new BadRequestException("Invalid user";
}
return facebook;
}
