Access Logging

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152

interface AccessLogEvent {
  // ========== Core Identification ==========
  id: string;                    // UUID v7 (time-ordered)
  timestamp: string;             // ISO 8601 with microseconds
  
  // ========== Actor (Who) ==========
  actor: {
    // Primary identifier - must be immutable
    type: 'USER' | 'SERVICE' | 'SYSTEM' | 'API_KEY';
    id: string;                  // Permanent, unique identifier
    
    // Human-readable attributes (may change over time)
    displayName?: string;        // e.g., "John Smith"
    email?: string;              // e.g., "john@company.com"
    
    // Authentication context
    authSession: {
      sessionId: string;         // Links to authentication event
      authMethod: string;        // 'SSO_SAML' | 'MFA_TOTP' | 'API_KEY'
      authTime: string;          // When authentication occurred
      mfaVerified: boolean;      // Whether MFA was used
    };
    
    // Role/permissions at access time
    roles: string[];             // ['admin', 'hr_viewer']
    effectivePermissions?: string[]; // Computed permissions used
  };
  
  // ========== Source (Where From) ==========
  source: {
    ip: string;                  // Client IP (consider proxies)
    originalIp?: string;         // X-Forwarded-For if applicable
    userAgent: string;           // Browser/client identification
    
    // Device identification (if available)
    device?: {
      id: string;                // Device fingerprint or registered ID
      type: 'DESKTOP' | 'MOBILE' | 'TABLET' | 'API_CLIENT';
      trusted: boolean;          // Is this a known/trusted device
    };
    
    // Geolocation (privacy considerations apply)
    geo?: {
      country: string;           // ISO country code
      region?: string;           // State/province
      city?: string;             // Only if allowed by policy
      coordinates?: {            // Rarely needed
        lat: number;
        lon: number;
        accuracy: number;
      };
    };
  };
  
  // ========== Target (What Was Accessed) ==========
  target: {
    type: 'DATABASE_RECORD' | 'FILE' | 'API_RESOURCE' | 
          'CONFIGURATION' | 'SECRET' | 'REPORT';
    
    // Resource identification
    id: string;                  // Unique resource identifier
    collection: string;          // Table, bucket, or path
    
    // For database access - record details
    records?: {
      count: number;             // Number of records accessed
      ids?: string[];            // Specific IDs (if reasonable count)
      range?: {                  // For range queries
        field: string;
        start: string;
        end: string;
      };
    };
    
    // Data classification
    classification: {
      level: 'PUBLIC' | 'INTERNAL' | 'CONFIDENTIAL' | 'RESTRICTED';
      categories: string[];      // ['PII', 'PHI', 'FINANCIAL']
    };
    
    // Fields accessed (for field-level logging)
    fields?: {
      requested: string[];       // Fields in the query
      returned: string[];        // Fields actually returned
      filtered: string[];        // Fields redacted by policy
    };
  };
  
  // ========== Access Details (How and What) ==========
  access: {
    operation: 'READ' | 'CREATE' | 'UPDATE' | 'DELETE' | 
               'EXPORT' | 'SHARE' | 'DOWNLOAD' | 'PRINT';
    
    // How the access occurred
    channel: 'WEB_UI' | 'API' | 'MOBILE_APP' | 'CLI' | 
             'DATABASE_DIRECT' | 'BATCH_JOB' | 'REPORT';
    
    // API/endpoint details
    endpoint?: {
      method: string;            // GET, POST, etc.
      path: string;              // /api/v1/customers
      queryParams?: object;      // Non-sensitive params
    };
    
    // Query details (for database access)
    query?: {
      type: 'SELECT' | 'INSERT' | 'UPDATE' | 'DELETE';
      sanitizedQuery?: string;   // Query with values removed
      executionTimeMs: number;
    };
    
    // Business justification (if captured)
    justification?: {
      required: boolean;         // Was break-glass required
      reason?: string;           // User-provided reason
      approver?: string;         // Who approved (if workflow)
    };
  };
  
  // ========== Result (What Happened) ==========
  result: {
    status: 'SUCCESS' | 'DENIED' | 'PARTIAL' | 'ERROR';
    
    // For denials
    denialReason?: string;       // 'INSUFFICIENT_PERMISSION' | 'RATE_LIMITED'
    policyViolated?: string;     // Which policy triggered denial
    
    // For successful access
    recordsReturned?: number;    // How many records
    bytesReturned?: number;      // Data volume
    truncated?: boolean;         // Was result set limited
    
    // Response time
    durationMs: number;
  };
  
  // ========== Context (Why) ==========
  context: {
    requestId: string;           // Correlation ID
    traceId?: string;            // Distributed tracing
    sessionId: string;           // User session
    
    // Application context
    application: string;         // Which app generated this
    environment: string;         // production, staging
    version: string;             // App version
    
    // Business context
    workflow?: string;           // Business process involved
    ticketId?: string;           // Support ticket triggering access
  };
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63

┌─────────────────────────────────────────────────────────────────────────────────┐
│                               USER / CLIENT                                      │
└───────────────────────────────────┬──────────────────────────────────────────────┘
                                    │ Request with Auth Token
                                    ▼
┌─────────────────────────────────────────────────────────────────────────────────┐
│                            API GATEWAY LAYER                                     │
│  ┌───────────────────────────────────────────────────────────────────────────┐  │
│  │                     Kong / AWS API Gateway / Envoy                         │  │
│  │                                                                            │  │
│  │  ACCESS LOG #1: Gateway Access Log                                         │  │
│  │  • Client IP, User-Agent                                                   │  │
│  │  • Request path, method, headers                                           │  │
│  │  • Authentication result (token validated)                                 │  │
│  │  • Response code, latency                                                  │  │
│  │  • Rate limiting decisions                                                 │  │
│  └───────────────────────────────────────────────────────────────────────────┘  │
└───────────────────────────────────┬──────────────────────────────────────────────┘
                                    │
                                    ▼
┌─────────────────────────────────────────────────────────────────────────────────┐
│                            APPLICATION LAYER                                     │
│  ┌───────────────────────────────────────────────────────────────────────────┐  │
│  │                     Node.js / Python / Java Service                        │  │
│  │                                                                            │  │
│  │  ACCESS LOG #2: Application Access Log                                     │  │
│  │  • User identity (from token claims)                                       │  │
│  │  • Business operation being performed                                      │  │
│  │  • Authorization decision (permitted?)                                     │  │
│  │  • Which resources/record IDs accessed                                     │  │
│  │  • Data classification of accessed resources                               │  │
│  │  • Business context (workflow, ticket, reason)                             │  │
│  │                                                                            │  │
│  │  ┌────────────────────────────────────────────────────────────────────┐   │  │
│  │  │  Access Logging Middleware / Interceptor                            │   │  │
│  │  │                                                                     │   │  │
│  │  │  • Wraps all data access operations                                │   │  │
│  │  │  • Captures pre/post execution context                             │   │  │
│  │  │  • Handles async/batch operations                                  │   │  │
│  │  │  • Standardized format across services                             │   │  │
│  │  └────────────────────────────────────────────────────────────────────┘   │  │
│  └───────────────────────────────────────────────────────────────────────────┘  │
└───────────────────────────────────┬──────────────────────────────────────────────┘
                                    │
                                    ▼
┌─────────────────────────────────────────────────────────────────────────────────┐
│                            DATABASE LAYER                                        │
│  ┌───────────────────────────────────────────────────────────────────────────┐  │
│  │                PostgreSQL / MySQL / MongoDB / S3                           │  │
│  │                                                                            │  │
│  │  ACCESS LOG #3: Database Audit Log                                         │  │
│  │  • Actual SQL/queries executed                                             │  │
│  │  • Tables and columns accessed                                             │  │
│  │  • Rows affected/returned                                                  │  │
│  │  • Connection identity                                                     │  │
│  │  • Query execution time                                                    │  │
│  │                                                                            │  │
│  │  PostgreSQL: pgaudit extension                                             │  │
│  │  MySQL: Enterprise Audit                                                   │  │
│  │  MongoDB: $auditLog                                                        │  │
│  │  S3: Server Access Logging                                                 │  │
│  └───────────────────────────────────────────────────────────────────────────┘  │
└─────────────────────────────────────────────────────────────────────────────────┘

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145

import { AccessLogger } from '@company/access-logging';
 
/**
 * Data access wrapper that ensures all access is logged
 */
class AuditedDataAccess<T> {
  private accessLogger: AccessLogger;
  private repository: Repository<T>;
  
  constructor(
    repository: Repository<T>,
    config: {
      resourceType: string;
      classification: DataClassification;
    }
  ) {
    this.accessLogger = new AccessLogger(config);
    this.repository = repository;
  }
  
  async findById(
    id: string,
    context: RequestContext
  ): Promise<T | null> {
    const accessEvent = this.accessLogger.startAccess({
      actor: context.authenticatedUser,
      source: context.requestSource,
      target: {
        type: 'DATABASE_RECORD',
        id: id,
        collection: this.repository.tableName,
      },
      access: {
        operation: 'READ',
        channel: context.channel,
      },
    });
    
    try {
      const result = await this.repository.findById(id);
      
      // Log successful access
      await accessEvent.complete({
        status: result ? 'SUCCESS' : 'SUCCESS',
        recordsReturned: result ? 1 : 0,
      });
      
      return result;
    } catch (error) {
      // Log failed access
      await accessEvent.error(error);
      throw error;
    }
  }
  
  async findByQuery(
    query: QuerySpec,
    context: RequestContext
  ): Promise<T[]> {
    const accessEvent = this.accessLogger.startAccess({
      actor: context.authenticatedUser,
      source: context.requestSource,
      target: {
        type: 'DATABASE_RECORD',
        collection: this.repository.tableName,
        // Log query parameters, not values
        records: {
          range: query.getRange(),
        },
      },
      access: {
        operation: 'READ',
        channel: context.channel,
        query: {
          type: 'SELECT',
          sanitizedQuery: query.toSanitizedString(), // No values!
        },
      },
    });
    
    try {
      const results = await this.repository.query(query);
      
      await accessEvent.complete({
        status: 'SUCCESS',
        recordsReturned: results.length,
        // Log IDs if reasonable count
        recordIds: results.length <= 100 
          ? results.map(r => r.id) 
          : undefined,
        truncated: results.length >= query.limit,
      });
      
      return results;
    } catch (error) {
      await accessEvent.error(error);
      throw error;
    }
  }
  
  /**
   * Bulk export requires extra logging
   */
  async exportBulk(
    criteria: ExportCriteria,
    context: RequestContext
  ): Promise<ExportResult> {
    // Bulk operations always require enhanced logging
    const accessEvent = this.accessLogger.startAccess({
      actor: context.authenticatedUser,
      source: context.requestSource,
      target: {
        type: 'DATABASE_RECORD',
        collection: this.repository.tableName,
        classification: { level: 'CONFIDENTIAL', categories: ['BULK_EXPORT'] },
      },
      access: {
        operation: 'EXPORT',
        channel: context.channel,
        justification: {
          required: true,
          reason: context.exportJustification,
          approver: context.exportApprover,
        },
      },
    });
    
    const result = await this.repository.exportBulk(criteria);
    
    await accessEvent.complete({
      status: 'SUCCESS',
      recordsReturned: result.recordCount,
      bytesReturned: result.sizeBytes,
    });
    
    // Additional alert for bulk export
    await this.alertService.notify('BULK_EXPORT', {
      user: context.authenticatedUser,
      recordCount: result.recordCount,
      destination: result.destination,
    });
    
    return result;
  }
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31

-- Enable pgaudit extension
CREATE EXTENSION IF NOT EXISTS pgaudit;
 
-- Configure audit logging for sensitive tables
-- Log all DML on customer tables
ALTER TABLE customers SET (pgaudit.log = 'write, read');
 
-- Configure role-based auditing
-- Log everything for admin role
ALTER ROLE admin_role SET pgaudit.log = 'all';
 
-- Application role: log only reads on sensitive data
ALTER ROLE app_service_role SET pgaudit.log = 'read';
 
-- Set session-level logging parameters
-- Log all DDL and DML statements
SET pgaudit.log = 'ddl, write';
 
-- Log the actual parameter values (careful: PII exposure!)
-- Usually disabled for sensitive data
SET pgaudit.log_parameter = off;
 
-- Include system catalog queries
SET pgaudit.log_catalog = on;
 
-- Log statement outcomes
SET pgaudit.log_level = log;
 
-- Example output in postgresql logs:
-- AUDIT: SESSION,1,1,READ,SELECT,TABLE,public.customers,
--        "SELECT id, email FROM customers WHERE id = $1"

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106

import { KinesisClient, GetRecordsCommand } from '@aws-sdk/client-kinesis';
import { KMSClient, DecryptCommand } from '@aws-sdk/client-kms';
 
interface DatabaseActivityEvent {
  type: 'DatabaseActivityMonitoringRecords';
  version: '1.1';
  databaseActivityEvents: {
    logTime: string;
    statementId: number;
    substatementId: number;
    objectType: 'TABLE' | 'FUNCTION' | 'INDEX';
    command: 'SELECT' | 'INSERT' | 'UPDATE' | 'DELETE';
    objectName: string;
    databaseName: string;
    dbUserName: string;
    remoteHost: string;
    remotePort: number;
    sessionId: string;
    rowCount: number;
    commandText: string;  // Full SQL (be careful!)
    paramList: string[];
    errorMessage?: string;
  }[];
}
 
class RDSActivityMonitor {
  private kinesis: KinesisClient;
  private kms: KMSClient;
  private accessLogger: AccessLogIngester;
  
  async processActivityStream(shardIterator: string): Promise<void> {
    while (true) {
      const response = await this.kinesis.send(new GetRecordsCommand({
        ShardIterator: shardIterator,
        Limit: 1000,
      }));
      
      for (const record of response.Records || []) {
        // Activity stream records are encrypted
        const decrypted = await this.decryptRecord(record.Data);
        const events = JSON.parse(decrypted) as DatabaseActivityEvent;
        
        for (const dbEvent of events.databaseActivityEvents) {
          await this.transformAndIngest(dbEvent);
        }
      }
      
      shardIterator = response.NextShardIterator;
      await sleep(100); // Rate control
    }
  }
  
  private async transformAndIngest(event: any): Promise<void> {
    // Transform RDS format to standard access log format
    const accessLog: AccessLogEvent = {
      id: generateUUID(),
      timestamp: event.logTime,
      
      actor: {
        type: 'SERVICE',
        id: event.dbUserName,
        authSession: {
          sessionId: event.sessionId,
          authMethod: 'DATABASE_AUTH',
        },
      },
      
      source: {
        ip: event.remoteHost,
        port: event.remotePort,
      },
      
      target: {
        type: 'DATABASE_RECORD',
        id: event.objectName,
        collection: `${event.databaseName}.${event.objectName}`,
      },
      
      access: {
        operation: this.mapCommand(event.command),
        channel: 'DATABASE_DIRECT',
        query: {
          type: event.command,
          sanitizedQuery: this.sanitizeQuery(event.commandText),
          executionTimeMs: event.latency,
        },
      },
      
      result: {
        status: event.errorMessage ? 'ERROR' : 'SUCCESS',
        recordsReturned: event.rowCount,
      },
    };
    
    await this.accessLogger.ingest(accessLog);
  }
  
  private sanitizeQuery(query: string): string {
    // Remove literal values to prevent PII logging
    return query
      .replace(/'[^']*'/g, '?')           // Remove string literals
      .replace(/\d+/g, '?')                // Remove numeric literals
      .replace(/\s+/g, ' ')                // Normalize whitespace
      .trim();
  }
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141

import { Request, Response, NextFunction } from 'express';
import { AccessLogger, AccessLogEvent } from '@company/audit';
 
interface AccessLoggingConfig {
  // Fields to exclude from logging (e.g., password, token)
  sensitiveParams: string[];
  sensitiveHeaders: string[];
  
  // Endpoints with special handling
  excludedPaths: string[];        // Don't log these (health checks)
  bulkOperationPaths: string[];   // Enhanced logging for these
  
  // Response body logging (careful!)
  logResponseBody: boolean;       // Usually false
  responseBodyMaxSize: number;    // Truncate if enabled
}
 
function createAccessLoggingMiddleware(
  accessLogger: AccessLogger,
  config: AccessLoggingConfig
): RequestHandler {
  
  return async (req: Request, res: Response, next: NextFunction) => {
    // Skip excluded paths
    if (config.excludedPaths.some(p => req.path.startsWith(p))) {
      return next();
    }
    
    const startTime = Date.now();
    const requestId = req.headers['x-request-id'] as string || generateUUID();
    
    // Capture original write to intercept response
    const originalWrite = res.write;
    const originalEnd = res.end;
    const chunks: Buffer[] = [];
    
    if (config.logResponseBody) {
      res.write = function(chunk: any, ...args: any[]): boolean {
        chunks.push(Buffer.from(chunk));
        return originalWrite.apply(res, [chunk, ...args]);
      };
      
      res.end = function(chunk: any, ...args: any[]): Response {
        if (chunk) chunks.push(Buffer.from(chunk));
        return originalEnd.apply(res, [chunk, ...args]);
      };
    }
    
    // Create access log event
    res.on('finish', async () => {
      const duration = Date.now() - startTime;
      
      const accessEvent: AccessLogEvent = {
        id: generateUUID(),
        timestamp: new Date().toISOString(),
        
        actor: extractActor(req),
        source: extractSource(req),
        
        target: {
          type: 'API_RESOURCE',
          id: req.path,
          collection: extractResourceCollection(req.path),
        },
        
        access: {
          operation: mapHttpMethodToOperation(req.method),
          channel: 'API',
          endpoint: {
            method: req.method,
            path: req.path,
            queryParams: sanitizeParams(req.query, config.sensitiveParams),
          },
        },
        
        result: {
          status: res.statusCode < 400 ? 'SUCCESS' : 
                  res.statusCode === 403 ? 'DENIED' : 'ERROR',
          durationMs: duration,
          bytesReturned: parseInt(res.get('content-length') || '0'),
          // Extract record count from response if available
          recordsReturned: extractRecordCount(res),
        },
        
        context: {
          requestId,
          traceId: req.headers['x-trace-id'] as string,
          sessionId: req.session?.id,
          application: 'api-gateway',
          environment: process.env.NODE_ENV || 'development',
          version: process.env.APP_VERSION || 'unknown',
        },
      };
      
      // Enhanced logging for bulk operations
      if (config.bulkOperationPaths.some(p => req.path.startsWith(p))) {
        accessEvent.access.operation = 'EXPORT';
        accessEvent.target.classification = {
          level: 'CONFIDENTIAL',
          categories: ['BULK_OPERATION'],
        };
      }
      
      await accessLogger.log(accessEvent);
    });
    
    next();
  };
}
 
// Helper functions
function extractActor(req: Request): AccessLogEvent['actor'] {
  const user = req.user; // From authentication middleware
  
  return {
    type: user?.serviceAccount ? 'SERVICE' : 'USER',
    id: user?.id || 'anonymous',
    displayName: user?.name,
    email: user?.email,
    authSession: {
      sessionId: req.session?.id || 'no-session',
      authMethod: req.authInfo?.method || 'UNKNOWN',
      authTime: req.authInfo?.authTime,
      mfaVerified: req.authInfo?.mfaVerified || false,
    },
    roles: user?.roles || [],
  };
}
 
function sanitizeParams(
  params: object,
  sensitiveFields: string[]
): object {
  const sanitized = { ...params };
  for (const field of sensitiveFields) {
    if (field in sanitized) {
      sanitized[field] = '[REDACTED]';
    }
  }
  return sanitized;
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105

interface AccessInvestigationService {
  /**
   * What did a user access during breach window?
   */
  async getUserAccessHistory(
    userId: string,
    startTime: Date,
    endTime: Date
  ): Promise<AccessSummary>;
  
  /**
   * Who accessed a specific record?
   */
  async getRecordAccessHistory(
    recordId: string,
    options?: { limit?: number; includeServiceAccess?: boolean }
  ): Promise<AccessorList>;
  
  /**
   * Reconstruct a complete request journey
   */
  async traceRequest(requestId: string): Promise<RequestJourney>;
}
 
// Example: OpenSearch/Elasticsearch queries for investigation
 
class AccessInvestigator {
  private esClient: ElasticsearchClient;
  
  /**
   * Breach scope assessment: What sensitive data did this user access?
   */
  async assessBreachScope(
    compromisedUserId: string,
    breachStart: Date,
    breachEnd: Date
  ): Promise<BreachScopeReport> {
    
    const response = await this.esClient.search({
      index: 'access-logs-*',
      body: {
        size: 0,
        query: {
          bool: {
            must: [
              { term: { 'actor.id': compromisedUserId } },
              { range: { timestamp: { gte: breachStart, lte: breachEnd } } },
              { terms: { 'target.classification.categories': ['PII', 'PHI', 'FINANCIAL'] } },
              { term: { 'result.status': 'SUCCESS' } },
            ],
          },
        },
        aggs: {
          by_classification: {
            terms: { field: 'target.classification.categories' },
          },
          by_resource: {
            terms: { field: 'target.collection', size: 100 },
            aggs: {
              unique_records: {
                cardinality: { field: 'target.id' },
              },
              sample_ids: {
                terms: { field: 'target.id', size: 10 },
              },
            },
          },
          by_operation: {
            terms: { field: 'access.operation' },
          },
          unique_records_accessed: {
            cardinality: { field: 'target.id' },
          },
          access_timeline: {
            date_histogram: {
              field: 'timestamp',
              calendar_interval: 'hour',
            },
          },
        },
      },
    });
    
    return this.formatBreachReport(response.aggregations);
  }
  
  /**
   * Detect anomalous access patterns
   */
  async detectAnomalies(options: AnomalyDetectionOptions): Promise<Anomaly[]> {
    // Volume-based: unusual access count
    const volumeAnomalies = await this.detectVolumeAnomalies(options);
    
    // Time-based: access outside normal hours
    const timeAnomalies = await this.detectTimeAnomalies(options);
    
    // Geography-based: access from unusual locations
    const geoAnomalies = await this.detectGeoAnomalies(options);
    
    // Behavior-based: unusual resources accessed
    const behaviorAnomalies = await this.detectBehaviorAnomalies(options);
    
    return [...volumeAnomalies, ...timeAnomalies, ...geoAnomalies, ...behaviorAnomalies];
  }
}