— Integration patterns
EDI integration patterns
One hundred and forty architectural patterns every EDI integration team rediscovers sooner or later. They live in the general software-architecture literature — Enterprise Integration Patterns by Hohpe & Woolf, Fowler's Circuit Breaker, AWS blog posts on backoff, IETF RFCs, Garcia-Molina & Salem Sagas, Nygard's Bulkhead, Kleppmann's delivery semantics, Debezium CDC, Dehghani's Data Mesh, Ongaro & Ousterhout's Raft, NIST SP 800-207 Zero Trust — but their EDI-specific incarnation for EDIFACT, X12 and UBL/AS4 flows is rarely written down in one place. This section closes that gap, covering twenty pattern families from loose coupling to resilience, synthetic monitoring, modern infrastructure, deep eventing, scaling and Zero Trust security.
Reliability
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Pattern · 01
Acknowledgements (functional ACK, MDN, EERP)
Three stacked receipt levels — protocol, functional, business — to distinguish "I received the bytes" from "the syntax is valid" from "I acted on it".
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Pattern · 02
Idempotency and deduplication (receiver)
An order must never be delivered twice. UNB control reference, ISA13, AS4 MessageId — how to anchor the uniqueness window.
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Pattern · 03
Idempotency Key (sender side)
The sender-side counterpart: generate, persist and reuse a stable key before any retry. Without it, receiver-side dedup is pointless.
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Pattern · 04
Retry, exponential backoff and circuit breaker
When the partner doesn't answer: exponential + jitter + ceiling, circuit breaker to avoid amplifying outages, dead-letter queue.
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Delivery semantics
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Pattern · 05
At-Least-Once Delivery
The default semantics of every realistic EDI deployment: delivery guaranteed at least once, possible duplicates, dedup on the receiver side. Kleppmann chap. 11.
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Pattern · 06
At-Most-Once Delivery
The fire-and-forget counterpart: zero or one delivery, never twice. Reserved for non-critical flows (telemetry, non-regulatory IFTSTA). Kafka acks=0.
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Architecture
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Pattern · 07
Internal canonical model
A pivot JSON schema to avoid the n × m mapping problem between partners: each partner only talks to the canonical model.
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Pattern · 08
Exception flow and escalation matrix
When validation fails, when the receipt is missing, when the partner drifts: the catalogue of escape hatches.
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Pattern · 09
Event Sourcing
Store the full history of business events as an append-only log and rebuild current state by replay. Fowler 2005, Young 2010.
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Pattern · 10
CQRS — Command Query Responsibility Segregation
Separate the write model from the read model. On an EDI hub: one command side accepts, one query side publishes KPIs, tracking, fiscal journal.
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Pattern · 11
Data Mesh applied to EDI
Dehghani's four principles (domain ownership, data as a product, self-service platform, federated governance) applied to a multi-domain EDI hub.
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Channels
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Pattern · 12
Message Channel
The named conduit between sender and receiver — the foundational brick of every EDI messaging stack (AS2, AS4, SFTP, Kafka). EIP §60.
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Pattern · 13
Point-to-Point Channel
One sender, one exclusive receiver. The default semantic of AS2 and most bilateral EDI connections. EIP §103.
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Pattern · 14
Publish-Subscribe Channel
One sender, several independent subscribers. The broadcast model of multi-target SBDH/PEPPOL and internal hub events. EIP §106.
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Pattern · 15
Competing Consumers
N competing consumers pull from the same channel to scale out horizontally. The scaling pattern for parsers and validators in high-volume hubs. EIP §502.
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Pattern · 16
Message Endpoint
The connection point between business code and the EDI messaging system — the abstraction layer that makes AS2/AS4/SFTP interchangeable. EIP §95.
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Pattern · 17
Datatype Channel
One channel, one type — the rule that makes consumers predictable and routing simple (edi.orders, edi.invoices…). EIP §111.
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Pattern · 18
Invalid Message Channel
The channel for well-formed but semantically invalid messages — distinct from Dead Letter Channel for technical errors. EIP §115.
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Pattern · 19
Guaranteed Delivery
The broker guarantee that no message is lost even on crash — Kafka acks=all, min.insync.replicas=2. EIP §122.
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Topology
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Pattern · 20
Pipes and Filters
Compose the pipeline as atomic stages (parse → validate → enrich → translate → ship) linked by channels. EIP §70.
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Pattern · 21
Message Bus
A shared backbone where ERP, WMS, TMS, portal, lake and EDI hub plug in. From N² spaghetti to 2N organised links. EIP §137.
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Pattern · 22
Message Store
Persist every passing message for audit, replay, history, 10-year fiscal proof. EIP §555.
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Routing
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Pattern · 23
Message Router
Stateless dispatch of a message to a channel based on its headers — type, partner, environment. The founding pattern of EDI routing (EIP §109).
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Pattern · 24
Content-Based Router
The router that inspects the payload to decide the destination: ship-to country, total amount, currency. EIP §230.
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Pattern · 25
Splitter
Break a composite message into multiple atomic messages. An EDIFACT INVOIC carrying 100 invoices becomes 100 messages. EIP §259.
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Pattern · 26
Aggregator
Recompose a message from several related messages: 15 DESADV consolidated into a monthly INVOIC. EIP §268.
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Pattern · 27
Dynamic Router
Router that learns its rules at runtime — each consumer announces its capabilities, the router updates its table. EIP §243.
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Pattern · 28
Message Filter
The selective filter — silent drop of non-matching messages, not to be confused with router. EIP §237.
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Pattern · 29
Resequencer
Reorder messages arriving out of order according to a sequenceId — useful after parallel splitting. EIP §283.
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Pattern · 30
Composed Message Processor
Splitter + Router + Aggregator in a structured pipeline — to process a 100-line INVOIC in parallel. EIP §294.
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Pattern · 31
Scatter-Gather
Fan-out/fan-in — query 5 suppliers in parallel (REQOTE) and aggregate responses. EIP §297.
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Transformation
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Pattern · 32
Message Translator
Convert a message from one schema to another: EDIFACT ORDERS to canonical JSON, X12 850 to SAP IDoc. EIP §85.
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Pattern · 33
Normalizer
Detect an incoming message's format (EDIFACT, X12, cXML, UBL) and route to the right Translator. The front door of a hub. EIP §352.
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Pattern · 34
Content Enricher
Inject into a message the fields it does not carry: resolve a GLN to an address, a GTIN to a product label. EIP §336.
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Process
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Pattern · 35
Process Manager
Orchestrate the PO → ORDRSP → DESADV → INVOIC → REMADV cycle as a stateful state machine with timers and compensations. EIP §312.
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Pattern · 36
Routing Slip
The message carries its own itinerary; each stage reads the next and forwards. Classic model of cXML PunchOut. EIP §301.
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Pattern · 37
Saga Choreography
Saga without a central orchestrator: each service reacts to domain events and emits its own. PO ↔ ASN ↔ INVOIC ↔ REMADV in pub/sub mode.
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Resilience
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Pattern · 38
Back-pressure
When downstream cannot keep up, slow upstream — TCP RWIN, Kafka quotas, Reactive Streams request(n), AS4 503 + Retry-After. Reactive Streams 2015.
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Pattern · 39
Bulkhead
Isolate thread, connection and memory pools per EDI partner: a downed Walmart no longer takes Carrefour, Stellantis, BNP with it. Nygard Release It! 2018.
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Pattern · 40
Rate Limiter
Cap accepted throughput per partner to protect downstream. Token bucket / leaky bucket, HTTP 429 + Retry-After, Kafka quotas. RFC 2697, 6585.
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Observability
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Pattern · 41
Wire Tap
Graft a passive observer onto a channel to feed lake, audit, KPI without disturbing the business flow. EIP §547.
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Pattern · 42
Message History
The message carries the list of every component it traversed — versions, timestamps, actions. The cornerstone of distributed debugging. EIP §551.
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Endpoints
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Pattern · 43
Dead Letter Channel
The channel a message goes to when it cannot be processed: broken syntax, unknown format, failed validation. Prevent silent loss. EIP §119.
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Pattern · 44
Claim Check
Externalise a large payload to an object store and only pass a reference through the queue. For 100 MB INVOIC files. EIP §358.
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Pattern · 45
Circuit Breaker
When an EDI partner is down, do not hammer them — open the circuit, fail fast, probe before reconnecting. Fowler, 2014.
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Pattern · 46
Polling Consumer
The pull consumer polling at regular interval — legacy SFTP/FTPS polling. EIP §494.
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Pattern · 47
Event-Driven Consumer
The push consumer notified in real time — the modern Kafka/SQS/SNS standard. EIP §498.
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Pattern · 48
Transactional Client
Business ↔ messaging atomicity — Outbox pattern guaranteeing that message sent = DB committed. EIP §484.
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Messaging styles
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Pattern · 49
Command Message
The order message — a clear action intent (ORDERS = place the order). EIP §145.
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Pattern · 50
Document Message
The document message — a business fact that flows, not a command (INVOIC, DESADV, PRICAT). EIP §147.
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Pattern · 51
Event Message
The notification message — real-time pub/sub, the modern Kafka pattern (OrderConfirmed, InvoicePaid). EIP §151.
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Management & monitoring
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Pattern · 52
Control Bus
The admin channel parallel to business — start, stop, reconfigure a component hot. EIP §540.
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Pattern · 53
Test Message
The synthetic canary — test INVOIC every 5 min to verify the chain breathes. EIP §569.
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Pattern · 54
Channel Purger
The "drain the queue" button — controlled ops tool with mandatory archive and audit. EIP §572.
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Pattern · 55
Smart Proxy
The smart proxy adding retries, cache, mTLS, observability in front of a partner service. EIP §558.
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Pattern · 56
Detour
The optional detour — enable/disable a step (audit, A/B test) without redeploying. EIP §545.
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Correlation & coordination
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Pattern · 57
Return Address
The message carries the reply address rather than deriving it from a directory. AS2 Receipt-Delivery-Option, AS4 ReplyPattern. EIP §159.
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Pattern · 58
Correlation Identifier
Every reply points back to the original request to close the loop: 997 AK1/AK2, CONTRL UCI/UCM, MDN Original-Message-ID. EIP §163.
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Pattern · 59
Format Indicator
The message declares its own format and version on the first line: UNH S009, GS08, AS2 Content-Type. EIP §180.
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Pattern · 60
Recipient List
The sender computes the exact set of recipients per message: multi-Receiver SBDH, PEPPOL 5-corner model for CTC. EIP §249.
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Endpoints & receivers
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Pattern · 61
Selective Consumer
Filtering on the queue side rather than in code — JMS selectors, Kafka headers — to avoid pull-and-drop. EIP §515.
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Pattern · 62
Durable Subscriber
The pub/sub subscriber whose subscription persists offline — Kafka consumer groups, JMS clientId. EIP §522.
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Pattern · 63
Idempotent Receiver
Consumer-side deduplication — distinct from producer idempotency, complementary for at-least-once brokers. EIP §528.
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Pattern · 64
Service Activator
The bridge between an async queue and a sync legacy API — the classic Camel/Spring Integration gateway. EIP §532.
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Pattern · 65
Messaging Bridge
The bridge between two heterogeneous brokers — to migrate progressively from Sterling AS2 to Kafka without disruption. EIP §133.
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Composition & translation
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Pattern · 66
Envelope Wrapper
The root EDI pattern — UNB/UNH, ISA/GS, SBDH — the envelope carrying identification, routing, ack, signature. EIP §330.
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Pattern · 67
Content Filter
Message pruning (vs Message Filter which drops the whole message) — strip unused PII, internal metadata, verbose lines. EIP §342.
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Pattern · 68
Mapping
The artifact materialising field-to-field correspondences between schemas — base of Message Translator and Canonical Model.
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Pattern · 69
Transactional Channel
The channel coupling DB commit and broker commit — XA on IBM MQ, Outbox on Kafka. Topological alias of Transactional Client.
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Pattern · 70
Message Broker
The star hub decoupling N senders and M receivers — a single exchange point instead of an N×N mesh. EIP §322.
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Topology & infrastructure
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Pattern · 71
Process Engine
The BPMN/workflow runtime running long-lived EDI Process Managers — Camunda, Temporal, Step Functions.
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Pattern · 72
Saga Orchestration
Long-running transaction with explicit compensations — the pragmatic way without XA, multi-system (Garcia-Molina/Salem, 1987).
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Pattern · 73
Outbox (architectural)
The buffer table turning two uncoordinated writes (DB + broker) into one atomic DB write — dominant pattern for ERP→Kafka.
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Pattern · 74
Inbox (architectural)
The mirror of Outbox on the consumer side — a journal of consumed events to prevent a broker retry from re-triggering a side effect.
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Pattern · 75
Change Data Capture
Capture DB changes in real time via WAL/binlog (Debezium) — the non-intrusive path to wire a legacy ERP onto a modern EDI hub.
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Eventing
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Pattern · 76
Event-Carried State Transfer
The event contains the full state — Fowler 2017. Consumers reconstruct a local cache without synchronous calls back to the producer.
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Pattern · 77
Event Notification
Minimal event (id + type + timestamp); interested consumer calls the producer API back for details. The lightweight counterpart of ECST.
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Pattern · 78
Transactional Outbox (deep dive)
Transactional Outbox in detail: table schema, polling vs CDC, ordering, idempotency, purge, observability.
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Pattern · 79
Transactional Inbox (deep dive)
The consumer-side mirror: inbox table recording idempotency key before any side effect, safe reprocessing under at-least-once.
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Pattern · 80
CDC pipeline (deep dive)
End-to-end CDC pipeline: source connector, schema registry, SMT, sink connectors, lag monitoring. Turning a legacy ERP into a streaming source of truth.
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Concurrency & scaling
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Pattern · 81
Leader Election
Elect one node out of N for a task that does not tolerate concurrency (single poller, scheduler). ZooKeeper, etcd, Raft, Kubernetes Lease.
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Pattern · 82
Consensus (Raft)
Distributed consensus algorithm by Ongaro & Ousterhout (2014). Splits the problem into leader election, log replication and safety. Basis of etcd, Consul, CockroachDB.
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Pattern · 83
Consistent Hashing
Key placement on a virtual ring that minimises rebalancing on node add/remove. Karger et al. 1997, basis of Amazon Dynamo, Cassandra, CDNs.
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Pattern · 84
Sharding
Horizontal data partitioning to scale beyond single-instance limits. Strategies: hash, range, lookup.
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Pattern · 85
Partition Tolerance (CAP)
The P of the CAP theorem (Brewer 2000). A distributed system must keep functioning under partition, choosing between consistency and availability.
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Security
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Pattern · 86
Zero Trust Architecture
Architecture with no trust perimeter: every request is authenticated, authorised and encrypted. NIST SP 800-207, Google BeyondCorp, Forrester 2010.
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Pattern · 87
Defense in Depth
Stack several independent defensive layers rather than betting on a single barrier. NIST SP 800-53, NSA, OWASP.
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Pattern · 88
Principle of Least Privilege
Every actor gets the strict minimum of rights required for its function. Saltzer & Schroeder 1975. Consequences for IAM, Kubernetes service accounts, EDI partners.
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Pattern · 89
Secrets Management
Full lifecycle of secrets (creds, keys, certs): generation, encrypted storage, distribution, rotation, revocation, audit. Vault, KMS, Secrets Manager.
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Pattern · 90
Mutual TLS Pattern
Bidirectional authentication via X.509 certificates — RFC 8446 (TLS 1.3). Cryptographic brick of Zero Trust and of every AS2/AS4 EDI flow.
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Resilience & migration
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Pattern · 91
Feature Flag
Decouple deployment of a new version (mapping, validator) from its visibility in production. LaunchDarkly, Unleash, Hodgson 2017 taxonomy.
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Pattern · 92
Blue-Green Deployment
Two identical environments in parallel, atomic switch by the traffic router. The zero-downtime infrastructure deployment pattern. Fowler 2010.
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Pattern · 93
Canary Release
Progressive rollout (1% → 10% → 50% → 100%) with SLO monitoring and automatic rollback. Sato 2014, SRE Google §16. Reference pattern for EDI rollout 2026.
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Pattern · 94
Dark Launch
Traffic is duplicated to the new version, its results compared to the old without returning to the partner. Github Scientist, Facebook Engineering.
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Pattern · 95
Chaos Engineering
Deliberately inject failures in controlled production to validate resilience. Netflix Chaos Monkey, principles of chaos, Rosenthal et al. 2020.
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Workflow & process
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Pattern · 96
State Machine (partner lifecycle)
Variant of the State Machine pattern for the technical lifecycle of an EDI partner: prospect, scoped, certs, tested, production-active, archived. Complement to the message State Machine.
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Pattern · 97
Temporal Workflow
Long-running workflow in code, durable execution, automatic retry, durable sleeps. Cadence (Uber) fork, adopted by Stripe, Snap, Doordash, HashiCorp Vault.
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Pattern · 98
Step Functions
Managed declarative workflow (AWS Step Functions ASL, Google Cloud Workflows, Azure Logic Apps) for cloud-native EDI sagas without maintaining an orchestrator.
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Pattern · 99
Compensating Action
The inverse operation that semantically cancels an already-committed step in a saga. Cornerstone of Long Lived Transactions (Garcia-Molina & Salem 1987).
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Pattern · 100
Retry With Jitter
Exponential backoff + random component to break client synchronisation and avoid retry storms. Marc Brooker AWS 2015, integrated in every modern library.
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Distributed transactions
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Pattern · 101
Two-Phase Commit (2PC)
Atomic distributed commit protocol formalised by Jim Gray (1978). Phase 1 prepare, phase 2 commit or abort. Blocking if coordinator dies, historical foundation of XA transactions.
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Pattern · 102
Three-Phase Commit (3PC)
Non-blocking variant of 2PC proposed by Dale Skeen (1981). Pre-commit phase inserted. Blocking under network partition, rarely used in production.
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Pattern · 103
Paxos consensus
Distributed consensus algorithm formalised by Leslie Lamport (1989, published 1998). Building block of Google Chubby, Cassandra LWT, Spanner. Famously hard to grasp.
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Pattern · 104
Byzantine Fault Tolerance
Family of protocols tolerating malicious nodes. Origin Lamport-Shostak-Pease 1982, PBFT Castro-Liskov 1999. Minimum quorum 3f+1, foundation of permissioned blockchains.
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Pattern · 105
Vector Clocks
Structure capturing causal order of distributed events (Mattern 1989, Fidge 1988, on Lamport 1978). Building block of Amazon Dynamo, Riak to detect concurrent writes.
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Stream processing
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Pattern · 106
Tumbling Window
Fixed-size non-overlapping time window. Cornerstone of periodic aggregations (hourly volume, daily KPIs, fiscal reports). Akidau Dataflow 2015, Flink, Spark, Kafka Streams.
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Pattern · 107
Sliding Window
Sliding time window with step smaller than size. Cornerstone for continuous metrics (moving average, error rate over past 5 min). Akidau Dataflow 2015.
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Pattern · 108
Session Window
Activity-based window started on an event, closed after inactivity gap. Suited to discontinuous interactions (INVOIC batch from a partner). Akidau Dataflow 2015.
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Pattern · 109
Watermarks
Stream time progression: 'all events with timestamp ≤ T have arrived'. Correctness/latency trade-off in any out-of-order system. Akidau Dataflow 2015.
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Pattern · 110
Exactly-Once Semantics
'Exactly once' processing guarantee in a distributed streaming pipeline. Combines idempotency, Chandy-Lamport checkpointing, Kafka transactions, sink 2PC.
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Messaging reliability
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Pattern · 111
CQRS for B2B event streams
Split the write model (EDI commands, sagas, ACK journals) from the read model (KPIs, tracking, fiscal archive) on a B2B hub. Young 2010, Fowler 2011.
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Pattern · 112
Event Sourcing with append-only EDI log
Persist every EDI business event in an immutable log, rebuild state by replay, native 10-year fiscal archive. Fowler 2005, eIDAS.
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Pattern · 113
Saga: choreography vs orchestration
Choice criteria between decentralised pub/sub topology and centralised orchestrator for long-running EDI sagas. Garcia-Molina 1987, Temporal, Camunda.
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Pattern · 114
Compensating Transactions
The inverse business operation that semantically undoes a committed saga step: negative ORDRSP, CRDADV, SEPA counter-transfer. Saga cornerstone.
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Pattern · 115
Transactional Outbox
Atomic DB+broker without XA via a local outbox table drained by polling or Debezium CDC. The dominant 2026 pattern for ERP→Kafka.
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Pattern · 116
Transactional Inbox
The consumer mirror of Outbox: deduplicate at-least-once by inserting message id in the same TX as the side effect. Vasters, Helland.
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Pattern · 117
Idempotent Receiver for EDI flows
Business-level idempotency on EDIFACT/X12/UBL contractual keys (UNB 0020, ISA13, BT-1, AS4 MessageId) with partner dedup windows. EIP §528.
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Pattern · 118
Message Deduplication Ledger
Unified cross-broker dedup registry for a multi-tenant hub: hot Redis, monthly-partitioned cold PostgreSQL, S3 archive. Helland 2012.
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Pattern · 119
Dead-Letter Queue: variants and runbooks
Five modern operational variants: tiered retry, per-cause DLQ, parking lot, leak probe, replay runbook. AWS SQS, Kafka, Spring.
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Pattern · 120
Poison Message Handling
Detect the message that systematically crashes the consumer (poison pill), isolate in a quarantine queue, analyse in sandbox. Nygard, OWASP ReDoS.
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Why every team rediscovers them
EDI is a domain where the transport standards (AS2, AS4, OFTP2) and the message standards (EDIFACT, X12, UBL) are public, but the integration practices — how to retry, where to deduplicate, when to give up, how to split a batch — stay in architects' heads and in private partner manuals. Every new team ends up tripping on the same wires: the X12 997 they confuse with the ORDRSP, the control reference number they reuse, the huge INVOIC that saturates the queue, the purchase order that lands twice during an outage. This section codifies those traps and their fix.
Reading list
- Hohpe G., Woolf B. — Enterprise Integration Patterns: Designing, Building, and Deploying Messaging Solutions, Addison-Wesley, 2003. The founding catalogue. The Message Idempotency, Guaranteed Delivery, Dead Letter Channel and Canonical Data Model patterns we cite throughout come from this book. enterpriseintegrationpatterns.com
- Fowler M. — Circuit Breaker (martinfowler.com, 2014). The canonical description of the pattern, picked up by every cloud-native stack since. martinfowler.com/bliki/CircuitBreaker.html
- RFC 5681 — TCP Congestion Control (IETF, September 2009). The IP-stack reference for exponential backoff, referenced by every modern HTTP library. rfc-editor.org/rfc/rfc5681
- AWS Architecture Blog — "Exponential Backoff And Jitter" (Marc Brooker, 2015). The reference article on why jitter breaks retry storms. aws.amazon.com/blogs/architecture/exponential-backoff-and-jitter
- Walmart Supplier Center — Walmart EDI Guidelines. The Walmart EDI manuals have formalised acknowledgement, retransmission and escalation practice for thirty years, diffusing across retail. supplier.walmart.com/edi
- OpenPEPPOL — PEPPOL Reception Profile — codifies the use of the AS4 NRR receipt in the network, transposable as a template for any cryptographic-receipt scheme.
- Canonical online index enterpriseintegrationpatterns.com/patterns/messaging — the home of the online EIP catalogue, used as the canonical reference for every routing and transformation pattern cited in this section.
- Apache Camel — EIP Reference. The reference open-source implementation of Hohpe's patterns: routing, splitter, aggregator, normalizer. Useful to confirm modern implementation choices. camel.apache.org — EIP
- Nygard M. — Release It! Design and Deploy Production-Ready Software, Pragmatic Bookshelf, 2007 (2nd ed. 2018). Stability patterns (bulkhead, circuit breaker, timeout, fail fast) applied to messaging pipelines.