Adding missing file

src/main/java/com/docusign/core/security/SecurityHelpers.java

@@ -0,0 +1,72 @@
+package com.docusign.core.security;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Base64;
+import java.util.List;
+import java.util.Random;
+
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.oauth2.client.authentication.OAuth2AuthenticationToken;
+import com.docusign.core.model.ApiType;
+import com.docusign.core.model.Session;
+import com.docusign.esign.client.auth.OAuth;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+public class SecurityHelpers {
+    public static List<String> getScopeList() {
+        List<String> scopes = new ArrayList<>();
+        for (ApiType scope : ApiType.values()) {
+            scopes.addAll(Arrays.asList(scope.getScopes()));
+        }
+        return scopes;
+    }
+
+    public static String generateCodeVerifier() {
+        byte[] randomBytes = new byte[32];
+        new Random().nextBytes(randomBytes);
+        return Base64.getUrlEncoder().withoutPadding().encodeToString(randomBytes);
+    }
+
+    public static String generateCodeChallenge(String codeVerifier) throws NoSuchAlgorithmException {
+        MessageDigest digest = MessageDigest.getInstance("SHA-256");
+        byte[] hash = digest.digest(codeVerifier.getBytes(StandardCharsets.UTF_8));
+        return Base64.getUrlEncoder().withoutPadding().encodeToString(hash);
+    }
+
+    public static String parseJsonField(String jsonResponse, String field) throws IOException {
+        ObjectMapper mapper = new ObjectMapper();
+        JsonNode jsonNode = mapper.readTree(jsonResponse);
+        return jsonNode.get(field).asText();
+    }
+
+    public static void setSpringSecurityAuthentication(
+        List<String> scopes,
+        String oAuthToken,
+        OAuth.UserInfo userInfo,
+        String accountId,
+        Session session,
+        String expiresIn) {
+        JWTOAuth2User principal = new JWTOAuth2User();
+        principal.setAuthorities(scopes);
+        principal.setCreated(userInfo.getCreated());
+        principal.setName(userInfo.getName());
+        principal.setGivenName(userInfo.getGivenName());
+        principal.setFamilyName(userInfo.getFamilyName());
+        principal.setSub(userInfo.getSub());
+        principal.setEmail(userInfo.getEmail());
+        principal.setAccounts(userInfo.getAccounts());
+        principal.setAccessToken(new OAuth.OAuthToken().accessToken(oAuthToken));
+
+        session.setTokenExpirationTime(System.currentTimeMillis() + Integer.parseInt(expiresIn) * 1000L);
+
+        OAuth2AuthenticationToken token = new OAuth2AuthenticationToken(principal, principal.getAuthorities(),
+                accountId);
+        SecurityContextHolder.getContext().setAuthentication(token);
+    }
+}