JSON-RPC reference

The Dev UI talks to the runtime through a JSON-RPC service (GoblinJsonRPCService). The same service is available over the Dev UI’s built-in JSON-RPC bridge, which is useful for scripting or CI validation. All methods read or mutate the in-memory MutableAssaultConfig.

Method Effect

Method	Effect
`getStatus`	Returns `active`, the active `profile`, the four assault toggles, the two client-side assault toggles, the `responseBodyEnabled` and `responseHeaderEnabled` toggles, the armed chaos `layers` (array of layer names), the `availableLayers` backed by an installed hook in this application (`SERVICE`, `HTTP_OUT`, `HTTP_IN`, plus `DATABASE` with a JDBC datasource and `MESSAGING` with Quarkus Messaging), and the target `level`.
`getConfig`	Returns the full mutable config (profile, toggles, client-side toggles, latency range, exception config, HTTP status config, response body config, response header rules under `headers`, armed chaos `layers`, `availableLayers`, level) plus `exceptionPresets`, the exception classes offered as quick picks in the Dev UI. Every preset is validated by the engine (loadable, extends `RuntimeException`, has a single-`String` constructor) so picking one never triggers the fallback.
`toggleActive` / `setActive(boolean)`	Enable/disable chaos entirely. Emits a WARN log. Returns `{ ok, active }`.
`setProfile(profile)`	Activate a predefined composite assault mode (`NONE`, `SLOW_FAILURE`, `INTERMITTENT`, `TIMEOUT`). Applies the profile defaults to the assault toggles; each toggle stays overridable afterwards.
`toggleLatency` / `toggleException` / `toggleHttpStatus` / `toggleDependencyDegradation` / `toggleResponseBody` / `toggleResponseHeader`	Flip the corresponding assault toggle on/off.
`toggleClientLatency` / `toggleClientException`	Flip the corresponding client-side assault toggle on/off (outgoing REST Client and Vert.x WebClient calls).
`setResponseBodyConfig(mode, percentage)`	Set the response body transformation (`TRUNCATE` or `INFLATE`) and its target size in percent. Invalid modes are rejected; out-of-range percentages are clamped with the correction surfaced in `warning`.
`setResponseHeaderInfo(name, action, value)`	Add or replace the rule applied to the named response header. `action` is case-insensitive (`SET` or `REMOVE`, the legacy `ADD`/`OVERRIDE` labels are accepted and mapped to `SET`); blank header names, names that are not RFC 9110 tokens, values containing CR, LF or control characters, and unknown actions are rejected with `ok=false`. `REMOVE` ignores the value.
`removeResponseHeader(name)`	Drop the rule configured for the named response header.
`setLatencyRange(minMs, maxMs)`	Set the min/max latency range.
`setExceptionConfig(type, message)`	Set the exception class name and message. The class must extend `RuntimeException` and have a single-`String` constructor; a non-RuntimeException or unknown class is kept in the config but flagged in `warning` (the engine falls back to `RuntimeException`).
`setHttpStatusConfig(code, message)`	Set the HTTP status code and response body.
`setTargetLevel(level)`	Set the percentage of affected requests (clamped to 0-100).
`disableAll()`	Kill switch: deactivates the engine, disables every assault type and client-side assault, and resets the profile to `NONE`. Returns `{ ok, active: false }` plus the full config.
`resetDefaults()`	Restore every toggle and parameter to its default value (profile `NONE`, latency `100-5000` ms, HTTP status `503`, body `TRUNCATE 50%`, layers `{HTTP_IN, HTTP_OUT}`, level `100`). Returns `{ ok }` plus the full config.
`applyConfig(config)`	Apply a (partial) config object: `profile` is applied first, then any provided field overrides — omitted fields keep their current value. The optional `headers` object replaces the whole set of response header rules (rules not listed are dropped); the optional `layers` array replaces the armed chaos layers (unknown layer names are skipped and surfaced in `warning`, an empty array restores the default layers). Unknown actions and header names that are not RFC 9110 tokens are skipped and surfaced in `warning`. Booleans and numbers given as strings (`"true"`, `"50"`) are converted; a value that cannot be converted is skipped and surfaced in `warning`. The payload is staged on a copy and published at once: when it is rejected (e.g. an unknown `profile`) the response is `{ ok: false, error }` and nothing is applied. Returns `{ ok, warning }` plus the full config. Used by the dashboard’s import, custom-profile and chaos-layer features.
`getCounters`	Return `{ total, since, byType, bySource }` with the session assault counters: the total number of assaults since the engine started (or the counters were last reset), the epoch timestamp of that window start (`since`), a per-type breakdown (`byType`) and a per-source breakdown (`bySource`, keyed by `server`, `service`, `rest-client`, `webclient`, `database`, `messaging`).
`resetCounters()`	Reset the assault counters to zero. Returns `{ ok }`.
`getHistory`	Return the assault history buffer. Each entry exposes the method, type, timestamp, the applied latency duration (`latencyMs`, 0 for non-latency assaults), the `source` (`server`, `service`, `rest-client`, `webclient`, `database`, `messaging`), and the active assault config snapshot at the time of the assault (`config`).
`clearHistory`	Empty the assault history buffer.
`getMarkdownReport`	Return `{ markdown, generatedAt }` with a factual Markdown report of the current configuration and assault history.

getStatus

Returns active, the active profile, the four assault toggles, the two client-side assault toggles, the responseBodyEnabled and responseHeaderEnabled toggles, the armed chaos layers (array of layer names), the availableLayers backed by an installed hook in this application (SERVICE, HTTP_OUT, HTTP_IN, plus DATABASE with a JDBC datasource and MESSAGING with Quarkus Messaging), and the target level.

getConfig

Returns the full mutable config (profile, toggles, client-side toggles, latency range, exception config, HTTP status config, response body config, response header rules under headers, armed chaos layers, availableLayers, level) plus exceptionPresets, the exception classes offered as quick picks in the Dev UI. Every preset is validated by the engine (loadable, extends RuntimeException, has a single-String constructor) so picking one never triggers the fallback.

toggleActive / setActive(boolean)

Enable/disable chaos entirely. Emits a WARN log. Returns { ok, active }.

setProfile(profile)

Activate a predefined composite assault mode (NONE, SLOW_FAILURE, INTERMITTENT, TIMEOUT). Applies the profile defaults to the assault toggles; each toggle stays overridable afterwards.

toggleLatency / toggleException / toggleHttpStatus / toggleDependencyDegradation / toggleResponseBody / toggleResponseHeader

Flip the corresponding assault toggle on/off.

toggleClientLatency / toggleClientException

Flip the corresponding client-side assault toggle on/off (outgoing REST Client and Vert.x WebClient calls).

setResponseBodyConfig(mode, percentage)

Set the response body transformation (TRUNCATE or INFLATE) and its target size in percent. Invalid modes are rejected; out-of-range percentages are clamped with the correction surfaced in warning.

setResponseHeaderInfo(name, action, value)

Add or replace the rule applied to the named response header. action is case-insensitive (SET or REMOVE, the legacy ADD/OVERRIDE labels are accepted and mapped to SET); blank header names, names that are not RFC 9110 tokens, values containing CR, LF or control characters, and unknown actions are rejected with ok=false. REMOVE ignores the value.

removeResponseHeader(name)

Drop the rule configured for the named response header.

setLatencyRange(minMs, maxMs)

Set the min/max latency range.

setExceptionConfig(type, message)

Set the exception class name and message. The class must extend RuntimeException and have a single-String constructor; a non-RuntimeException or unknown class is kept in the config but flagged in warning (the engine falls back to RuntimeException).

setHttpStatusConfig(code, message)

Set the HTTP status code and response body.

setTargetLevel(level)

Set the percentage of affected requests (clamped to 0-100).

disableAll()

Kill switch: deactivates the engine, disables every assault type and client-side assault, and resets the profile to NONE. Returns { ok, active: false } plus the full config.

resetDefaults()

Restore every toggle and parameter to its default value (profile NONE, latency 100-5000 ms, HTTP status 503, body TRUNCATE 50%, layers {HTTP_IN, HTTP_OUT}, level 100). Returns { ok } plus the full config.

applyConfig(config)

Apply a (partial) config object: profile is applied first, then any provided field overrides — omitted fields keep their current value. The optional headers object replaces the whole set of response header rules (rules not listed are dropped); the optional layers array replaces the armed chaos layers (unknown layer names are skipped and surfaced in warning, an empty array restores the default layers). Unknown actions and header names that are not RFC 9110 tokens are skipped and surfaced in warning. Booleans and numbers given as strings ("true", "50") are converted; a value that cannot be converted is skipped and surfaced in warning. The payload is staged on a copy and published at once: when it is rejected (e.g. an unknown profile) the response is { ok: false, error } and nothing is applied. Returns { ok, warning } plus the full config. Used by the dashboard’s import, custom-profile and chaos-layer features.

getCounters

Return { total, since, byType, bySource } with the session assault counters: the total number of assaults since the engine started (or the counters were last reset), the epoch timestamp of that window start (since), a per-type breakdown (byType) and a per-source breakdown (bySource, keyed by server, service, rest-client, webclient, database, messaging).

resetCounters()

Reset the assault counters to zero. Returns { ok }.

getHistory

Return the assault history buffer. Each entry exposes the method, type, timestamp, the applied latency duration (latencyMs, 0 for non-latency assaults), the source (server, service, rest-client, webclient, database, messaging), and the active assault config snapshot at the time of the assault (config).

clearHistory

Empty the assault history buffer.

getMarkdownReport

Return { markdown, generatedAt } with a factual Markdown report of the current configuration and assault history.

Every mutating method returns the full configuration as JsonObject (the same shape as getConfig), so the Dev UI treats the response as a single source of truth. The legacy top-level keys (mode, percentage, minMilliseconds, maxMilliseconds, type, message, code, level) remain present for backward compatibility.