Pipelines

Pipelines chain guards together and run them on text.

Creating Pipelines

With pipe() (shorthand)

import { pipe, promptInjection, pii, keyword } from 'open-guardrail';

const pipeline = pipe(
  promptInjection({ action: 'block' }),
  pii({ entities: ['email'], action: 'mask' }),
  keyword({ denied: ['hack'], action: 'block' }),
);

const result = await pipeline.run('user input');

With createPipeline() (full control)

import { createPipeline, promptInjection, pii } from 'open-guardrail';

const pipeline = createPipeline({
  guards: [
    promptInjection({ action: 'block' }),
    pii({ entities: ['email'], action: 'mask' }),
  ],
  type: 'input',
  mode: 'fail-fast',
  onError: 'block',
  timeoutMs: 5000,
  dryRun: false,
});

Pipeline Modes

fail-fast (default)

Stops at the first block action. Best for input validation where you want to reject fast.

run-all

Runs every guard regardless of results. Useful when you need all results (audit logging, analytics).

Dry Run Mode

Test guards without actually blocking:

const pipeline = createPipeline({
  guards: [...],
  dryRun: true,  // reports what would happen, but always passes
});

Error Handling

When a guard throws or times out:

onError	Behavior
'block' (default)	Treat error as block
'allow'	Treat error as allow (fail-open)
'warn'	Treat error as warning

Event Hooks

const pipeline = pipe(promptInjection({ action: 'block' }));

pipeline.on('guard:before', ({ guardName, text }) => { ... });
pipeline.on('guard:after', ({ guardName, result }) => { ... });
pipeline.on('guard:blocked', ({ guardName, result }) => { ... });
pipeline.on('guard:error', ({ guardName, error }) => { ... });

Debug Mode

Log every guard execution to console:

const pipeline = createPipeline({
  guards: [promptInjection({ action: 'block' }), pii({ entities: ['email'], action: 'mask' })],
  debug: true,
});

await pipeline.run('test input');
// [guardrail] pipeline start | mode=fail-fast type=input guards=2 dryRun=false
// [guardrail] input: "test input"
// [guardrail]   ✓ prompt-injection: allow (0ms)
// [guardrail]   ✓ pii: allow (0ms)
// [guardrail] result: PASSED (allow) 1ms

Cleanup

await pipeline.dispose();  // cleanup guard resources