deepgram-enterprise-rbac

Deepgram Enterprise RBAC

Overview

Role-based access control for enterprise Deepgram deployments. Maps five application roles to Deepgram API key scopes, implements scoped key provisioning via the Deepgram Management API, Express permission middleware, team management with auto-provisioned keys, and automated key rotation.

Deepgram Scope Reference

Instructions

Step 1: Define Roles and Scope Mapping

interface Role {
  name: string;
  deepgramScopes: string[];
  keyExpiry: number;        // Days
  description: string;
}

const ROLES: Record<string, Role> = {
  admin: {
    name: 'Admin',
    deepgramScopes: ['member'],
    keyExpiry: 90,
    description: 'Full access — project and key management',
  },
  developer: {
    name: 'Developer',
    deepgramScopes: ['listen', 'speak'],
    keyExpiry: 90,
    description: 'STT and TTS — no management access',
  },
  analyst: {
    name: 'Analyst',
    deepgramScopes: ['usage:read'],
    keyExpiry: 365,
    description: 'Read-only usage metrics',
  },
  service: {
    name: 'Service Account',
    deepgramScopes: ['listen'],
    keyExpiry: 90,
    description: 'STT only — for automated systems',
  },
  auditor: {
    name: 'Auditor',
    deepgramScopes: ['usage:read', 'keys:read'],
    keyExpiry: 30,
    description: 'Read-only audit access',
  },
};

Step 2: Scoped Key Provisioning

import { createClient } from '@deepgram/sdk';

class DeepgramKeyManager {
  private admin: ReturnType<typeof createClient>;
  private projectId: string;

  constructor(adminKey: string, projectId: string) {
    this.admin = createClient(adminKey);
    this.projectId = projectId;
  }

  async createScopedKey(userId: string, roleName: string): Promise<{
    keyId: string;
    key: string;
    scopes: string[];
    expiresAt: string;
  }> {
    const role = ROLES[roleName];
    if (!role) throw new Error(`Unknown role: ${roleName}`);

    const expirationDate = new Date(Date.now() + role.keyExpiry * 86400000);

    const { result, error } = await this.admin.manage.createProjectKey(
      this.projectId,
      {
        comment: `${roleName}:${userId}:${new Date().toISOString().split('T')[0]}`,
        scopes: role.deepgramScopes,
        expiration_date: expirationDate.toISOString(),
      }
    );

    if (error) throw new Error(`Key creation failed: ${error.message}`);

    console.log(`Created ${roleName} key for ${userId} (expires ${expirationDate.toISOString().split('T')[0]})`);

    return {
      keyId: result.key_id,
      key: result.key,
      scopes: role.deepgramScopes,
      expiresAt: expirationDate.toISOString(),
    };
  }

  async revokeKey(keyId: string) {
    const { error } = await this.admin.manage.deleteProjectKey(
      this.projectId, keyId
    );
    if (error) throw new Error(`Key revocation failed: ${error.message}`);
    console.log(`Revoked key: ${keyId}`);
  }

  async listKeys() {
    const { result, error } = await this.admin.manage.getProjectKeys(this.projectId);
    if (error) throw error;

    return result.api_keys.map((k: any) => ({
      keyId: k.api_key_id,
      comment: k.comment,
      scopes: k.scopes,
      created: k.created,
      expiration: k.expiration_date,
    }));
  }
}

Step 3: Permission Middleware

import { Request, Response, NextFunction } from 'express';

interface AuthenticatedRequest extends Request {
  user?: { id: string; role: string; deepgramKeyId: string };
}

function requireRole(...allowedRoles: string[]) {
  return (req: AuthenticatedRequest, res: Response, next: NextFunction) => {
    if (!req.user) {
      return res.status(401).json({ error: 'Authentication required' });
    }

    if (!allowedRoles.includes(req.user.role)) {
      console.warn(`Access denied: user ${req.user.id} (${req.user.role}) tried to access ${req.path}`);
      return res.status(403).json({
        error: 'Insufficient permissions',
        required: allowedRoles,
        current: req.user.role,
      });
    }

    next();
  };
}

function requireScope(...requiredScopes: string[]) {
  return (req: AuthenticatedRequest, res: Response, next: NextFunction) => {
    if (!req.user) {
      return res.status(401).json({ error: 'Authentication required' });
    }

    const role = ROLES[req.user.role];
    const hasScopes = requiredScopes.every(
      s => role.deepgramScopes.includes(s) || role.deepgramScopes.includes('member')
    );

    if (!hasScopes) {
      return res.status(403).json({
        error: 'Missing required Deepgram scopes',
        required: requiredScopes,
        current: role.deepgramScopes,
      });
    }

    next();
  };
}

// Route examples:
app.post('/api/transcribe', requireScope('listen'), transcribeHandler);
app.post('/api/tts', requireScope('speak'), ttsHandler);
app.get('/api/usage', requireScope('usage:read'), usageHandler);
app.post('/api/keys', requireRole('admin'), createKeyHandler);
app.get('/api/audit', requireRole('admin', 'auditor'), auditHandler);

Step 4: Team Management

interface Team {
  id: string;
  name: string;
  projectId: string;       // Deepgram project ID
  members: Array<{
    userId: string;
    role: string;
    keyId: string;
    joinedAt: string;
  }>;
}

class TeamManager {
  private keyManager: DeepgramKeyManager;

  constructor(adminKey: string, projectId: string) {
    this.keyManager = new DeepgramKeyManager(adminKey, projectId);
  }

  async addMember(team: Team, userId: string, role: string) {
    // Provision Deepgram key with role scopes
    const key = await this.keyManager.createScopedKey(userId, role);

    team.members.push({
      userId,
      role,
      keyId: key.keyId,
      joinedAt: new Date().toISOString(),
    });

    console.log(`Added ${userId} to ${team.name} as ${role}`);
    return key;
  }

  async removeMember(team: Team, userId: string) {
    const member = team.members.find(m => m.userId === userId);
    if (!member) throw new Error(`User ${userId} not in team`);

    // Revoke Deepgram key
    await this.keyManager.revokeKey(member.keyId);

    team.members = team.members.filter(m => m.userId !== userId);
    console.log(`Removed ${userId} from ${team.name}, key revoked`);
  }

  async changeRole(team: Team, userId: string, newRole: string) {
    const member = team.members.find(m => m.userId === userId);
    if (!member) throw new Error(`User ${userId} not in team`);

    // Revoke old key, create new key with new role scopes
    await this.keyManager.revokeKey(member.keyId);
    const newKey = await this.keyManager.createScopedKey(userId, newRole);

    member.role = newRole;
    member.keyId = newKey.keyId;

    console.log(`Changed ${userId} role to ${newRole}`);
    return newKey;
  }
}

Step 5: Automated Key Rotation

async function rotateExpiringKeys(
  keyManager: DeepgramKeyManager,
  db: any,
  daysBeforeExpiry = 7
) {
  const keys = await keyManager.listKeys();
  const now = Date.now();
  const threshold = now + daysBeforeExpiry * 86400000;
  let rotated = 0;

  for (const key of keys) {
    if (!key.expiration) continue;
    const expiresAt = new Date(key.expiration).getTime();

    if (expiresAt < threshold) {
      // Parse role from comment (format: "role:userId:date")
      const [role, userId] = (key.comment ?? '').split(':');
      if (!role || !userId) {
        console.warn(`Cannot rotate key ${key.keyId} — unknown format: ${key.comment}`);
        continue;
      }

      console.log(`Rotating key for ${userId} (${role}), expires ${key.expiration}`);

      // Create new key
      const newKey = await keyManager.createScopedKey(userId, role);

      // Update database with new key ID
      await db.query(
        'UPDATE team_members SET key_id = $1 WHERE user_id = $2',
        [newKey.keyId, userId]
      );

      // Revoke old key (after a grace period, or immediately)
      await keyManager.revokeKey(key.keyId);
      rotated++;
    }
  }

  console.log(`Rotated ${rotated} keys expiring within ${daysBeforeExpiry} days`);
  return rotated;
}

Step 6: Access Control Matrix

Output

• Five-role permission model with Deepgram scope mapping
• Scoped API key provisioning via Management API
• Express middleware (role-based and scope-based)
• Team management with auto-provisioned/revoked keys
• Automated key rotation for expiring keys

Error Handling

Resources

• API Key Management
• Project Management
• Deepgram Enterprise