Align event-subscription-template.yaml with OWASP requirements

[rartych]

Problem description
event-subscription-template.yaml needs to be aligned with OWASP requirements

Expected behavior
Update event-subscription-template.yaml with limits/restrictions to be used in the same way in Subscription API definitions.

Alternative solution

Additional context
Rules documentation:
https://github.com/camaraproject/Commonalities/blob/main/documentation/Linting-rules.md#5-owasp-api-security-top-10-2023-rules

[rartych]

##Initial review

Summary of Errors

Total errors found: 37

Line	Component	Error Type	Issue
141	Subscriptions array response	array-limit	Missing maxItems
254	ErrorInfo.status	integer-format	Missing format
254	ErrorInfo.status	integer-limit	Missing min/max
257	ErrorInfo.code	string-limit	Missing maxLength
260	ErrorInfo.message	string-limit	Missing maxLength
264	XCorrelator	string-limit	Missing maxLength
280	SubscriptionRequest.sink	string-limit	Missing maxLength
327	Config.subscriptionExpireTime	string-limit	Missing maxLength
332	Config.subscriptionMaxEvents	integer-format	Missing format
332	Config.subscriptionMaxEvents	integer-limit	Missing min/max
374	PlainCredential.identifier	string-limit	Missing maxLength
377	PlainCredential.secret	string-limit	Missing maxLength
387	AccessTokenCredential.accessToken	string-limit	Missing maxLength
390	AccessTokenCredential.accessTokenExpiresUtc	string-limit	Missing maxLength
452	Subscription.sink	string-limit	Missing maxLength
471	Subscription.startsAt	string-limit	Missing maxLength
478	Subscription.expiresAt	string-limit	Missing maxLength
519	SubscriptionId	string-limit	Missing maxLength
533	CloudEvent.id	string-limit	Missing maxLength
564	Source	string-limit	Missing maxLength
580	DateTime	string-limit	Missing maxLength
618	SubscriptionStarted.initiationDescription	string-limit	Missing maxLength
648	SubscriptionUpdated.updateDescription	string-limit	Missing maxLength
680	SubscriptionEnded.terminationDescription	string-limit	Missing maxLength
723	HTTPSettings.headers (additionalProperties)	string-limit	Missing maxLength
750	MQTTSettings.topicName	string-limit	Missing maxLength
752	MQTTSettings.qos	integer-limit	Missing min/max
757	MQTTSettings.expiry	integer-limit	Missing min/max
784	AMQPSettings.address	string-limit	Missing maxLength
786	AMQPSettings.linkName	string-limit	Missing maxLength
793	AMQPSettings.linkProperties (additionalProperties)	string-limit	Missing maxLength
815	ApacheKafkaSettings.topicName	string-limit	Missing maxLength
817	ApacheKafkaSettings.partitionKeyExtractor	string-limit	Missing maxLength
819	ApacheKafkaSettings.clientId	string-limit	Missing maxLength
821	ApacheKafkaSettings.ackMode	integer-format	Missing format
821	ApacheKafkaSettings.ackMode	integer-limit	Missing min/max
845	NATSSettings.subject	string-limit	Missing maxLength

---

Proposed Solutions

1. Line 141: Subscriptions Array Response

Current:

responses:
  "200":
    content:
      application/json:
        schema:
          type: array
          items:
            $ref: "#/components/schemas/Subscription"

Proposed:

responses:
  "200":
    content:
      application/json:
        schema:
          type: array
          items:
            $ref: "#/components/schemas/Subscription"
          maxItems: 1000

Rationale: Prevents unbounded result sets. 1000 is a reasonable upper limit for subscription listings. Consider pagination for larger datasets.

---

2. Lines 254 (2 errors): ErrorInfo.status

Current:

status:
  type: integer
  description: HTTP status code

Proposed:

status:
  type: integer
  format: int32
  minimum: 100
  maximum: 599
  description: HTTP status code

Rationale: HTTP status codes are int32 values ranging from 100-599.

---

3. Line 257: ErrorInfo.code

Current:

code:
  type: string
  description: Error code

Proposed:

code:
  type: string
  pattern: ^[A-Z_]+$
  maxLength: 64
  description: Error code

Rationale: Error codes typically use UPPER_SNAKE_CASE. 64 characters accommodates descriptive error codes.

---

4. Line 260: ErrorInfo.message

Current:

message:
  type: string
  description: Error message

Proposed:

message:
  type: string
  maxLength: 512
  description: Error message

Rationale: 512 characters allows detailed error messages without being excessive.

---

5. Line 264: XCorrelator

Current:

XCorrelator:
  type: string
  description: Correlation ID

Proposed:

XCorrelator:
  type: string
  pattern: ^[a-zA-Z0-9-_:;.\/<>{}]{0,256}$
  maxLength: 256
  description: Correlation ID
  example: "b4333c46-49c0-4f62-80d7-f0ef930f1c46"

Rationale: Matches the pattern from CAMARA_common.yaml for consistency.

---

6. Line 280: SubscriptionRequest.sink

Current:

sink:
  type: string
  format: uri
  description: The webhook URL

Proposed:

sink:
  type: string
  format: uri
  maxLength: 2048
  description: The webhook URL

Rationale: URLs can be lengthy. 2048 characters is a common browser/server limit and provides adequate space for complex URLs with query parameters.

---

7. Line 327: Config.subscriptionExpireTime

Current:

subscriptionExpireTime:
  type: string
  format: date-time
  description: Subscription expiration time

Proposed:

subscriptionExpireTime:
  type: string
  format: date-time
  maxLength: 64
  description: Subscription expiration time

Rationale: RFC 3339 date-time strings. 64 characters accommodates all common formats.

---

8. Lines 332 (2 errors): Config.subscriptionMaxEvents

Current:

subscriptionMaxEvents:
  type: integer
  description: Maximum number of events

Proposed:

subscriptionMaxEvents:
  type: integer
  format: int32
  minimum: 1
  maximum: 1000000
  description: Maximum number of events

Rationale:

• int32 format for reasonable event counts
• Minimum of 1 (at least one event)
• Maximum of 1,000,000 prevents resource exhaustion while allowing high-volume subscriptions

---

9. Line 374: PlainCredential.identifier

Current:

identifier:
  type: string
  description: Username or identifier

Proposed:

identifier:
  type: string
  maxLength: 256
  description: Username or identifier

Rationale: 256 characters is sufficient for most username/identifier schemes.

---

10. Line 377: PlainCredential.secret

Current:

secret:
  type: string
  format: password
  description: Password or secret

Proposed:

secret:
  type: string
  format: password
  maxLength: 512
  description: Password or secret

Rationale: 512 characters accommodates long passwords, passphrases, and API keys.

---

11. Line 387: AccessTokenCredential.accessToken

Current:

accessToken:
  type: string
  description: Bearer token

Proposed:

accessToken:
  type: string
  maxLength: 4096
  description: Bearer token

Rationale: JWT tokens can be lengthy (especially with many claims). 4096 bytes is a common limit for bearer tokens.

---

12. Line 390: AccessTokenCredential.accessTokenExpiresUtc

Current:

accessTokenExpiresUtc:
  type: string
  format: date-time
  description: Token expiration time

Proposed:

accessTokenExpiresUtc:
  type: string
  format: date-time
  maxLength: 64
  description: Token expiration time

Rationale: Same as other date-time fields - 64 characters for RFC 3339 format.

---

13. Line 452: Subscription.sink

Current:

sink:
  type: string
  format: uri
  description: The webhook URL

Proposed:

sink:
  type: string
  format: uri
  maxLength: 2048
  description: The webhook URL

Rationale: Consistent with SubscriptionRequest.sink (line 280).

---

14. Line 471: Subscription.startsAt

Current:

startsAt:
  type: string
  format: date-time
  description: Subscription start time

Proposed:

startsAt:
  type: string
  format: date-time
  maxLength: 64
  description: Subscription start time

Rationale: RFC 3339 date-time format.

---

15. Line 478: Subscription.expiresAt

Current:

expiresAt:
  type: string
  format: date-time
  description: Subscription expiration time

Proposed:

expiresAt:
  type: string
  format: date-time
  maxLength: 64
  description: Subscription expiration time

Rationale: RFC 3339 date-time format.

---

16. Line 519: SubscriptionId

Current:

SubscriptionId:
  type: string
  format: uuid
  description: Unique subscription identifier

Proposed:

SubscriptionId:
  type: string
  format: uuid
  maxLength: 36
  description: Unique subscription identifier

Rationale: UUID string format is exactly 36 characters (32 hex digits + 4 hyphens): "123e4567-e89b-12d3-a456-426614174000"

---

17. Line 533: CloudEvent.id

Current:

id:
  type: string
  description: Event unique identifier

Proposed:

id:
  type: string
  maxLength: 256
  description: Event unique identifier

Rationale: CloudEvents spec doesn't mandate a specific format. 256 characters accommodates various ID schemes (UUIDs, URNs, custom formats).

---

18. Line 564: Source

Current:

Source:
  type: string
  format: uri
  description: Event source URI

Proposed:

Source:
  type: string
  format: uri
  maxLength: 2048
  description: Event source URI

Rationale: URIs can be lengthy. 2048 characters is standard for URI limits.

---

19. Line 580: DateTime

Current:

DateTime:
  type: string
  format: date-time
  description: RFC 3339 date-time

Proposed:

DateTime:
  type: string
  format: date-time
  maxLength: 64
  description: RFC 3339 date-time

Rationale: Standard date-time limit for RFC 3339 format.

---

20. Line 618: SubscriptionStarted.initiationDescription

Current:

initiationDescription:
  type: string
  description: Description of subscription initiation

Proposed:

initiationDescription:
  type: string
  maxLength: 512
  description: Description of subscription initiation

Rationale: 512 characters allows detailed descriptions without being excessive.

---

21. Line 648: SubscriptionUpdated.updateDescription

Current:

updateDescription:
  type: string
  description: Description of subscription update

Proposed:

updateDescription:
  type: string
  maxLength: 512
  description: Description of subscription update

Rationale: Consistent with other description fields.

---

22. Line 680: SubscriptionEnded.terminationDescription

Current:

terminationDescription:
  type: string
  description: Description of subscription termination

Proposed:

terminationDescription:
  type: string
  maxLength: 512
  description: Description of subscription termination

Rationale: Consistent with other description fields.

---

23. Line 723: HTTPSettings.headers (additionalProperties)

Current:

headers:
  type: object
  additionalProperties:
    type: string
  description: HTTP headers

Proposed:

headers:
  type: object
  additionalProperties:
    type: string
    maxLength: 8192
  description: HTTP headers

Rationale: HTTP header values can be lengthy (especially Authorization headers with tokens). 8192 bytes is a common web server limit for header values.

---

24. Line 750: MQTTSettings.topicName

Current:

topicName:
  type: string
  description: MQTT topic name

Proposed:

topicName:
  type: string
  maxLength: 256
  description: MQTT topic name

Rationale: MQTT topic names typically range from a few characters to ~200. 256 provides adequate headroom while preventing abuse.

---

25. Line 752: MQTTSettings.qos

Current:

qos:
  type: integer
  description: Quality of Service level

Proposed:

qos:
  type: integer
  format: int32
  minimum: 0
  maximum: 2
  description: Quality of Service level (0, 1, or 2)

Rationale: MQTT QoS levels are 0 (at most once), 1 (at least once), or 2 (exactly once).

---

26. Line 757: MQTTSettings.expiry

Current:

expiry:
  type: integer
  description: Message expiry interval in seconds

Proposed:

expiry:
  type: integer
  format: int32
  minimum: 0
  maximum: 2147483647
  description: Message expiry interval in seconds

Rationale:

• int32 format (MQTT v5 uses 4-byte integer)
• Minimum 0 (no expiry)
• Maximum 2,147,483,647 seconds (~68 years, max int32 value per MQTT spec)

---

27. Line 784: AMQPSettings.address

Current:

address:
  type: string
  description: AMQP address

Proposed:

address:
  type: string
  maxLength: 512
  description: AMQP address

Rationale: AMQP addresses can include queue names, routing keys, and exchange names. 512 characters is generous.

---

28. Line 786: AMQPSettings.linkName

Current:

linkName:
  type: string
  description: AMQP link name

Proposed:

linkName:
  type: string
  maxLength: 256
  description: AMQP link name

Rationale: AMQP link names are typically short identifiers. 256 characters is sufficient.

---

29. Line 793: AMQPSettings.linkProperties (additionalProperties)

Current:

linkProperties:
  type: object
  additionalProperties:
    type: string
  description: AMQP link properties

Proposed:

linkProperties:
  type: object
  additionalProperties:
    type: string
    maxLength: 1024
  description: AMQP link properties

Rationale: AMQP properties can contain various metadata. 1024 characters provides flexibility.

---

30. Line 815: ApacheKafkaSettings.topicName

Current:

topicName:
  type: string
  description: Kafka topic name

Proposed:

topicName:
  type: string
  pattern: ^[a-zA-Z0-9._-]+$
  maxLength: 249
  description: Kafka topic name

Rationale:

• Kafka topic names have a max length of 249 characters
• Valid characters: alphanumeric, period, underscore, hyphen
• Pattern ensures compliance with Kafka naming rules

---

31. Line 817: ApacheKafkaSettings.partitionKeyExtractor

Current:

partitionKeyExtractor:
  type: string
  description: Expression to extract partition key

Proposed:

partitionKeyExtractor:
  type: string
  maxLength: 512
  description: Expression to extract partition key

Rationale: Extraction expressions can be complex JSONPath or similar expressions. 512 characters is reasonable.

---

32. Line 819: ApacheKafkaSettings.clientId

Current:

clientId:
  type: string
  description: Kafka client identifier

Proposed:

clientId:
  type: string
  maxLength: 256
  description: Kafka client identifier

Rationale: Kafka client IDs are typically short but can be descriptive. 256 characters is sufficient.

---

33. Lines 821 (2 errors): ApacheKafkaSettings.ackMode

Current:

ackMode:
  type: integer
  description: Acknowledgment mode

Proposed:

ackMode:
  type: integer
  format: int32
  minimum: 0
  maximum: 2
  description: Acknowledgment mode (0=no ack, 1=leader ack, 2=all replicas ack)

Rationale: Kafka acknowledgment modes:

• 0: No acknowledgment
• 1: Leader acknowledgment only
• 2: All in-sync replicas acknowledgment

---

34. Line 845: NATSSettings.subject

Current:

subject:
  type: string
  description: NATS subject

Proposed:

subject:
  type: string
  maxLength: 256
  description: NATS subject

Rationale: NATS subjects can include wildcards and hierarchies. 256 characters accommodates complex subject patterns.

---

Summary of Changes by Category

String Length Constraints

Field Type	Proposed maxLength	Count
URLs/URIs	2048	3
Tokens	4096	1
Secrets/Passwords	512	1
Descriptions	512	3
HTTP Headers	8192	1
Date-time strings	64	6
UUIDs	36	1
Correlation IDs	256	1
Error codes	64	1
Error messages	512	1
Identifiers	256	4
Topic names	249-256	3
Addresses	512	1
Link names	256	1
Properties	1024	1
Expressions	512	1
Event IDs	256	1

Integer Constraints

Field	Format	Min	Max
HTTP status	int32	100	599
Max events	int32	1	1000000
MQTT QoS	int32	0	2
MQTT expiry	int32	0	2147483647
Kafka ackMode	int32	0	2

Array Constraints

Field	Proposed maxItems
Subscriptions list	1000

[PedroDiez]

Thanks for the input @rartych

Just a minor note in case we consider to increase ErrorInfo.code to 96 characteres to be aligned with Commonalities CAMARA_common.yaml

3. Line 257: ErrorInfo.code
maxLength of 64 is fine so far (longest Code is MULTIEVENT_COMBINATION_TEMPORARILY_NOT_SUPPORTED (48 characters)