# Seeing every event of a journey

## What you want to do

The log stopped at Pat's charge, so no record says how Pat's journey ended. You want to see every event of a journey as it happens, without writing a reporter of your own.

## The code

The shop is [chapter 31](https://itinera-dev.org/book/rust/31-stopping-a-journey-when-its-log-fails.md)'s, with one more reporter. `DebugReporter`, from `itinera::report`, comes with `itinera`, and prints every event of a journey on a line of its own. The workflow lists it first:

Rust, from the program [`ch32_seeing_every_event_of_a_journey`](https://github.com/itinera-dev/book/blob/main/rust/examples/ch32_seeing_every_event_of_a_journey.rs)

```rust
#[workflow(name = "orders", reporters = [DebugReporter, Log, Desk], policies = [Notify])]
```

Rust, the same in its asynchronous form, from the program [`ch32_seeing_every_event_of_a_journey_async`](https://github.com/itinera-dev/book/blob/main/rust/examples/ch32_seeing_every_event_of_a_journey_async.rs)

```rust
#[workflow(
    name = "orders",
    reporters = [DebugReporter, Desk],
    async_reporters = [Log],
    policies = [Notify]
)]
```

The log is [chapter 31](https://itinera-dev.org/book/rust/31-stopping-a-journey-when-its-log-fails.md)'s, the desk is [chapter 11](https://itinera-dev.org/book/rust/11-naming-a-journey.md)'s and `notify` is [chapter 19](https://itinera-dev.org/book/rust/19-letting-policies-act-on-the-outside-world.md)'s.

In the asynchronous form, `DebugReporter` stays under `reporters` too, since printing waits for nothing, and the reporters under `reporters` receive each event before those under `async_reporters`. `main` runs Pat's order alone, and prints:

What `ch32_seeing_every_event_of_a_journey` prints, recorded in [`ch32_seeing_every_event_of_a_journey.txt`](https://github.com/itinera-dev/book/blob/main/rust/expected/ch32_seeing_every_event_of_a_journey.txt)

```text
Pat's order:
Event { sequence: 1, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358384048 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: JourneyStarted { initial_keys: ["card", "customer", "gift_card", "order", "parcel", "price"] } }
log orders A-15 #1 journey_started card, customer, gift_card, order, parcel, price
Event { sequence: 2, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358494850 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: AttemptStarted { step: StepAttempt { step: StepName { name: "lookup" }, attempt: 1 } } }
log orders A-15 #2 attempt_started lookup, attempt 1
Event { sequence: 3, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358534694 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: ServiceProvided { step: StepAttempt { step: StepName { name: "lookup" }, attempt: 1 }, key: "order_book", provider: ProviderName("ledger"), implementation: Implementation { name: "ch32_seeing_every_event_of_a_journey::Ledger" }, data: None } }
log orders A-15 #3 service_provided lookup gets order_book from ledger, a ch32_seeing_every_event_of_a_journey::Ledger
the order book has no order A-15 yet
Event { sequence: 4, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358597163 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: StepSucceeded { step: StepAttempt { step: StepName { name: "lookup" }, attempt: 1 } } }
log orders A-15 #4 step_succeeded lookup
Event { sequence: 5, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358638290 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: ContributionCommitted { key: "completed", source: Step(StepAttempt { step: StepName { name: "lookup" }, attempt: 1 }) } }
log orders A-15 #5 contribution_committed completed
Event { sequence: 6, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358705836 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: HookCalled { hook: Step { policy: PolicyName("already_completed"), hook: OnStepSuccess, step: StepAttempt { step: StepName { name: "lookup" }, attempt: 1 } }, lifecycle: None } }
log orders A-15 #6 hook_called already_completed: on step success of lookup
Event { sequence: 7, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358741056 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: AttemptStarted { step: StepAttempt { step: StepName { name: "price" }, attempt: 1 } } }
log orders A-15 #7 attempt_started price, attempt 1
Event { sequence: 8, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358777468 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: OptionalInputAbsent { key: "discount", requester: Step(StepAttempt { step: StepName { name: "price" }, attempt: 1 }) } }
log orders A-15 #8 optional_input_absent discount
Event { sequence: 9, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358818731 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: StepSucceeded { step: StepAttempt { step: StepName { name: "price" }, attempt: 1 } } }
log orders A-15 #9 step_succeeded price
Event { sequence: 10, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358852815 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: ContributionCommitted { key: "amount", source: Step(StepAttempt { step: StepName { name: "price" }, attempt: 1 }) } }
log orders A-15 #10 contribution_committed amount
Event { sequence: 11, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358888211 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: AttemptStarted { step: StepAttempt { step: StepName { name: "charge" }, attempt: 1 } } }
log orders A-15 #11 attempt_started charge, attempt 1
Event { sequence: 12, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358932113 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: ServiceProvided { step: StepAttempt { step: StepName { name: "charge" }, attempt: 1 }, key: "payments", provider: ProviderName("bank"), implementation: Implementation { name: "ch32_seeing_every_event_of_a_journey::Bank" }, data: None } }
log orders A-15 #12 service_provided charge gets payments from bank, a ch32_seeing_every_event_of_a_journey::Bank
the bank charges 50 for order A-15
Event { sequence: 13, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 358993910 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: StepSucceeded { step: StepAttempt { step: StepName { name: "charge" }, attempt: 1 } } }
Event { sequence: 14, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 359022110 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: JourneyAborted { abort: ReporterFailed { step: Some(StepName { name: "charge" }), error: "the logging service is down" } } }
the journey was aborted (reporter failed: the logging service is down)
```

What the asynchronous form `ch32_seeing_every_event_of_a_journey_async` prints, recorded in [`ch32_seeing_every_event_of_a_journey_async.txt`](https://github.com/itinera-dev/book/blob/main/rust/expected/ch32_seeing_every_event_of_a_journey_async.txt)

```text
Event { sequence: 1, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362243087 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: JourneyStarted { initial_keys: ["card", "customer", "gift_card", "order", "parcel", "price"] } }
log orders A-15 #1 journey_started card, customer, gift_card, order, parcel, price
Event { sequence: 2, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362336101 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: AttemptStarted { step: StepAttempt { step: StepName { name: "lookup" }, attempt: 1 } } }
log orders A-15 #2 attempt_started lookup, attempt 1
Event { sequence: 3, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362375427 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: ServiceProvided { step: StepAttempt { step: StepName { name: "lookup" }, attempt: 1 }, key: "order_book", provider: ProviderName("ledger"), implementation: Implementation { name: "ch32_seeing_every_event_of_a_journey_async::Ledger" }, data: None } }
log orders A-15 #3 service_provided lookup gets order_book from ledger, a ch32_seeing_every_event_of_a_journey_async::Ledger
the order book has no order A-15 yet
Event { sequence: 4, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362437154 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: StepSucceeded { step: StepAttempt { step: StepName { name: "lookup" }, attempt: 1 } } }
log orders A-15 #4 step_succeeded lookup
Event { sequence: 5, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362568875 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: ContributionCommitted { key: "completed", source: Step(StepAttempt { step: StepName { name: "lookup" }, attempt: 1 }) } }
log orders A-15 #5 contribution_committed completed
Event { sequence: 6, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362608040 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: HookCalled { hook: Step { policy: PolicyName("already_completed"), hook: OnStepSuccess, step: StepAttempt { step: StepName { name: "lookup" }, attempt: 1 } }, lifecycle: None } }
log orders A-15 #6 hook_called already_completed: on step success of lookup
Event { sequence: 7, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362648116 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: AttemptStarted { step: StepAttempt { step: StepName { name: "price" }, attempt: 1 } } }
log orders A-15 #7 attempt_started price, attempt 1
Event { sequence: 8, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362689539 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: OptionalInputAbsent { key: "discount", requester: Step(StepAttempt { step: StepName { name: "price" }, attempt: 1 }) } }
log orders A-15 #8 optional_input_absent discount
Event { sequence: 9, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362729420 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: StepSucceeded { step: StepAttempt { step: StepName { name: "price" }, attempt: 1 } } }
log orders A-15 #9 step_succeeded price
Event { sequence: 10, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362761457 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: ContributionCommitted { key: "amount", source: Step(StepAttempt { step: StepName { name: "price" }, attempt: 1 }) } }
log orders A-15 #10 contribution_committed amount
Event { sequence: 11, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362793989 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: AttemptStarted { step: StepAttempt { step: StepName { name: "charge" }, attempt: 1 } } }
log orders A-15 #11 attempt_started charge, attempt 1
Event { sequence: 12, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362834176 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: ServiceProvided { step: StepAttempt { step: StepName { name: "charge" }, attempt: 1 }, key: "payments", provider: ProviderName("bank"), implementation: Implementation { name: "ch32_seeing_every_event_of_a_journey_async::Bank" }, data: None } }
log orders A-15 #12 service_provided charge gets payments from bank, a ch32_seeing_every_event_of_a_journey_async::Bank
the bank charges 50 for order A-15
Event { sequence: 13, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362904217 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: StepSucceeded { step: StepAttempt { step: StepName { name: "charge" }, attempt: 1 } } }
Event { sequence: 14, timestamp: Timestamp { instant: SystemTime { tv_sec: 1791996170, tv_nsec: 362928182 } }, journey_id: JourneyId("A-15"), workflow: WorkflowName("orders"), body: JourneyAborted { abort: ReporterFailed { step: Some(StepName { name: "charge" }), error: "the logging service is down" } } }
order A-15 aborted
```

## How it works

1. **A ready-made reporter prints every event.** `DebugReporter` prints each event as Rust's `Debug` shows it: its sequence number, its timestamp, the journey's ID, the workflow and the body, with everything the body carries. It suits trying a workflow out, debugging one and watching a test run. A reporter for the shop's real log still formats its own lines, as the log does.
2. **It never fails.** So `DebugReporter` never costs a journey, as [chapter 31](https://itinera-dev.org/book/rust/31-stopping-a-journey-when-its-log-fails.md) said every reporter should.
3. **Reporters receive each event in the order the workflow lists them.** `DebugReporter` comes first, so it printed event 13, the charge's `step_succeeded`, before the log failed on it.
4. **`journey_aborted` reaches every reporter but the one that failed.** Event 14 reached `DebugReporter`, and not the log. It names the abort's reason, `ReporterFailed`, the step the journey was in, `charge`, and the log's error.

Pat's journey is now on record to its end. But the shop still has to refund Pat, and no line holds the receipt the bank gave: the charge never got to commit it. Nor does any line name Pat: they name the journey, `A-15`.

## Outcomes

We have shown how a ready-made reporter shows every event of a journey, up to its end.

| The usual way                                                                  | With Itinera                                                                                     |
| ------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------ |
| Seeing what a request did means adding print statements, then taking them out. | A reporter that comes with Itinera prints every event, listed once on the workflow.              |
| A crash in one part of the logging often hides what happened next.             | `journey_aborted` reaches every reporter but the one that failed, with the reason and the error. |