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applyCommentAction Action

Attach a free form comment to matching exchanges to make later review and grep across a capture much faster.

A capture file with a thousand exchanges is almost impossible to navigate without metadata. applyCommentAction lets you leave human readable notes on the exchanges that matter, the same way comments make a complicated code base easier to follow. The cost is one extra line in the rule, and the payoff is a capture that you and your team can re open weeks later and still understand.

When to use this action

Reach for applyCommentAction when you want a human readable note attached to selected exchanges. The comment changes nothing about the transport, it is metadata that shows up in the UI, exports, and downstream processing.

Typical situations include:

  • Marking exchanges that match a known bug so reviewers find them at a glance.
  • Documenting why a rule fired, useful when the rule file is long and shared across a team.
  • Building reports where each annotated exchange is grouped under a short description.
  • Leaving a breadcrumb during a long capture session, similar to a code comment in a long pull request.

The action evaluates on responseHeaderReceivedFromRemote. Pair it with content or status code filters to highlight just the interesting subset.

Real world examples

Flag every 5xx response from a backend

Useful while reproducing an intermittent server error. The comment makes those exchanges easy to find later.

rules:
- filter:
    typeKind: FilterCollection
    operation: And
    children:
    - typeKind: HostFilter
      pattern: api.example.com
    - typeKind: StatusCodeServerErrorFilter
  actions:
  - typeKind: ApplyCommentAction
    comment: "Backend 5xx, see ticket APP-1742"

Document why a rule modifies a request

If you have several rules in a file, a comment on each one helps newcomers understand the intent without reading the .NET docs.

rules:
- filter:
    typeKind: HostFilter
    pattern: legacy.example.com
  actions:
  - typeKind: ApplyCommentAction
    comment: "Legacy host requires TLS 1.2, see runbook section 4.3"
  - typeKind: ForceTlsVersionAction
    tlsVersion: Tls12

Mark slow exchanges for later analysis

Combine with throttling so any test run automatically labels the requests that came through the bottleneck.

rules:
- filter:
    typeKind: HostFilter
    pattern: media.example.com
  actions:
  - typeKind: AverageThrottleAction
    bandwidthBytesPerSeconds: 65536
    throttleChannel: All
  - typeKind: ApplyCommentAction
    comment: "Throttled to 64 KB/s for slow 3G test"

Reference

applyCommentAction

Description

Add comment to exchange. Comment has no effect on the stream behaviour.

Evaluation scope

Evaluation scope defines the timing where this filter will be applied.

responseHeaderReceivedFromRemote This scope occurs the moment fluxzy has done parsing the response header.

YAML configuration name

applyCommentAction

Settings

The following table describes the customizable properties available for this action:

Property Type Description DefaultValue
comment string

Example of usage

The following examples apply this action to any exchanges

Add comment Hello fluxzy.

rules:
- filter:
    typeKind: AnyFilter
  actions:
  - typeKind: ApplyCommentAction
    comment: Hello fluxzy

.NET reference

View definition of ApplyCommentAction for .NET integration.

See also

The following actions are related to this action:

Frequently asked questions

Does the comment change the network behaviour?

No. It is metadata only. Fluxzy displays it in the UI and exports it with the exchange, but the request and response bytes are untouched.

Can I search captures by comment?

Yes. The commentSearchFilter and hasCommentFilter filters let you build downstream rules that act on annotated exchanges.

How is this different from applyTagAction?

Comments are free form text aimed at humans. Tags are structured identifiers aimed at filters and programmatic processing.

Will the comment appear in exported HAR files?

Yes. The comment is included alongside the exchange metadata so external tooling can read it without using Fluxzy directly.

Learn more about Fluxzy rules