Java API Reference

Java API Reference v1.1.4

Functions

generateCitations()

Convert markdown links to numbered citations.

[Example](https://example.com) becomes Example[1] with [1]: <https://example.com> in the reference list. Images ![alt](url) are preserved unchanged.

Signature:

public static CitationResult generateCitations(String markdown)

Example:

var result = generateCitations("value");

Parameters:

Name	Type	Required	Description
`markdown`	`String`	Yes	The markdown

Returns: CitationResult

createEngine()

Create a new crawl engine with the given configuration.

If config is null, uses CrawlConfig.default(). Returns an error if the configuration is invalid.

Signature:

public static CrawlEngineHandle createEngine(CrawlConfig config) throws CrawlError

Example:

var result = createEngine(new CrawlConfig());

Parameters:

Name	Type	Required	Description
`config`	`Optional<CrawlConfig>`	No	The configuration options

Returns: CrawlEngineHandle

Errors: Throws CrawlErrorException.

scrape()

Scrape a single URL, returning extracted page data.

Signature:

public static ScrapeResult scrape(CrawlEngineHandle engine, String url) throws CrawlError

Example:

var result = scrape(new CrawlEngineHandle(), "value");

Parameters:

Name	Type	Required	Description
`engine`	`CrawlEngineHandle`	Yes	The crawl engine handle
`url`	`String`	Yes	The URL to fetch

Returns: ScrapeResult

Errors: Throws CrawlErrorException.

crawl()

Crawl a website starting from url, following links up to the configured depth.

Signature:

public static CrawlResult crawl(CrawlEngineHandle engine, String url) throws CrawlError

Example:

var result = crawl(new CrawlEngineHandle(), "value");

Parameters:

Name	Type	Required	Description
`engine`	`CrawlEngineHandle`	Yes	The crawl engine handle
`url`	`String`	Yes	The URL to fetch

Returns: CrawlResult

Errors: Throws CrawlErrorException.

mapUrls()

Discover all pages on a website by following links and sitemaps.

Signature:

public static MapResult mapUrls(CrawlEngineHandle engine, String url) throws CrawlError

Example:

var result = mapUrls(new CrawlEngineHandle(), "value");

Parameters:

Name	Type	Required	Description
`engine`	`CrawlEngineHandle`	Yes	The crawl engine handle
`url`	`String`	Yes	The URL to fetch

Returns: MapResult

Errors: Throws CrawlErrorException.

interact()

Execute browser actions on a single page.

Signature:

public static InteractionResult interact(CrawlEngineHandle engine, String url, List<PageAction> actions) throws CrawlError

Example:

var result = interact(new CrawlEngineHandle(), "value", List.of());

Parameters:

Name	Type	Required	Description
`engine`	`CrawlEngineHandle`	Yes	The crawl engine handle
`url`	`String`	Yes	The URL to fetch
`actions`	`List<PageAction>`	Yes	The actions

Returns: InteractionResult

Errors: Throws CrawlErrorException.

batchScrape()

Scrape multiple URLs concurrently.

Signature:

public static BatchScrapeResults batchScrape(CrawlEngineHandle engine, List<String> urls) throws CrawlError

Example:

var result = batchScrape(new CrawlEngineHandle(), List.of());

Parameters:

Name	Type	Required	Description
`engine`	`CrawlEngineHandle`	Yes	The crawl engine handle
`urls`	`List<String>`	Yes	The urls

Returns: BatchScrapeResults

Errors: Throws CrawlErrorException.

batchCrawl()

Crawl multiple seed URLs concurrently, each following links to configured depth.

Signature:

public static BatchCrawlResults batchCrawl(CrawlEngineHandle engine, List<String> urls) throws CrawlError

Example:

var result = batchCrawl(new CrawlEngineHandle(), List.of());

Parameters:

Name	Type	Required	Description
`engine`	`CrawlEngineHandle`	Yes	The crawl engine handle
`urls`	`List<String>`	Yes	The urls

Returns: BatchCrawlResults

Errors: Throws CrawlErrorException.

Types

ActionResult

Result from a single page action execution.

Field	Type	Default	Description
`actionIndex`	`long`	—	Zero-based index of the action in the sequence.
`actionType`	`String`	—	The type of action that was executed.
`success`	`boolean`	—	Whether the action completed successfully.
`data`	`Optional<Object>`	`null`	Action-specific return data (screenshot bytes, JS return value, scraped HTML).
`error`	`Optional<String>`	`null`	Error message if the action failed.

ArticleMetadata

Article metadata extracted from article:* Open Graph tags.

Field	Type	Default	Description
`publishedTime`	`Optional<String>`	`null`	The article publication time.
`modifiedTime`	`Optional<String>`	`null`	The article modification time.
`author`	`Optional<String>`	`null`	The article author.
`section`	`Optional<String>`	`null`	The article section.
`tags`	`List<String>`	`Collections.emptyList()`	The article tags.

BatchCrawlResult

Result from a single URL in a batch crawl operation.

Field	Type	Default	Description
`url`	`String`	—	The seed URL that was crawled.
`result`	`Optional<CrawlResult>`	`null`	The crawl result, if successful.
`error`	`Optional<String>`	`null`	The error message, if the crawl failed.

BatchCrawlResults

Aggregate result of a batch crawl, exposing per-URL results plus precomputed counts.

The counts are derived once at construction so every binding language can read them as plain integer fields without re-iterating the results vector.

Field	Type	Default	Description
`results`	`List<BatchCrawlResult>`	`Collections.emptyList()`	Per-URL crawl results, in the order seed URLs were submitted.
`totalCount`	`long`	—	Total number of seed URLs in the batch (equal to `results.len()`).
`completedCount`	`long`	—	Number of seed URLs whose crawl succeeded (`error` is `null`).
`failedCount`	`long`	—	Number of seed URLs whose crawl failed (`error` is `Some`).

BatchCrawlStreamRequest

Request to begin a multi-URL streaming crawl.

Wraps a set of seed URLs for delivery through the streaming-adapter binding surface. Required as a struct because alef’s streaming adapter requires a named request type — primitives are not supported.

Field	Type	Default	Description
`urls`	`List<String>`	`Collections.emptyList()`	The seed URLs to crawl. Each URL is followed independently up to the engine’s configured depth.

BatchScrapeResult

Result from a single URL in a batch scrape operation.

Field	Type	Default	Description
`url`	`String`	—	The URL that was scraped.
`result`	`Optional<ScrapeResult>`	`null`	The scrape result, if successful.
`error`	`Optional<String>`	`null`	The error message, if the scrape failed.

BatchScrapeResults

Aggregate result of a batch scrape, exposing per-URL results plus precomputed counts.

The counts are derived once at construction so every binding language can read them as plain integer fields without re-iterating the results vector.

Field	Type	Default	Description
`results`	`List<BatchScrapeResult>`	`Collections.emptyList()`	Per-URL scrape results, in the order URLs were submitted.
`totalCount`	`long`	—	Total number of URLs in the batch (equal to `results.len()`).
`completedCount`	`long`	—	Number of URLs whose scrape succeeded (`error` is `null`).
`failedCount`	`long`	—	Number of URLs whose scrape failed (`error` is `Some`).

BrowserConfig

Browser fallback configuration.

Field	Type	Default	Description
`mode`	`BrowserMode`	`BrowserMode.AUTO`	When to use the headless browser fallback.
`backend`	`BrowserBackend`	`BrowserBackend.CHROMIUMOXIDE`	Browser backend used to render JavaScript-heavy pages.
`endpoint`	`Optional<String>`	`null`	CDP WebSocket endpoint for connecting to an external browser instance.
`timeout`	`Duration`	`30000ms`	Timeout for browser page load and rendering (in milliseconds when serialized).
`wait`	`BrowserWait`	`BrowserWait.NETWORK_IDLE`	Wait strategy after browser navigation.
`waitSelector`	`Optional<String>`	`null`	CSS selector to wait for when `wait` is `Selector`.
`extraWait`	`Optional<Duration>`	`null`	Extra time to wait after the wait condition is met.
`proxy`	`Optional<ProxyConfig>`	`null`	Proxy for browser fetches. Overrides `CrawlConfig.proxy` when set. Native backend supports http/https only (no SOCKS5).
`blockUrlPatterns`	`List<String>`	`Collections.emptyList()`	URL patterns to block before the network request fires. Supports `*` wildcards. Useful for skipping ads/analytics/large images. Honored by `BrowserBackend.Native`; chromiumoxide ignores this field today.
`evalScript`	`Optional<String>`	`null`	JavaScript snippet evaluated after navigation completes. Scraping captures the native backend result in `ScrapeResult.browser.eval_result`. Interactions run this script before page actions on both browser backends but do not include the script result in `InteractionResult`.
`robotsUserAgent`	`Optional<String>`	`null`	User-agent used when fetching robots.txt. Defaults to `BrowserConfig.user_agent` (or crawlberg’s default) if unset. Native only.
`captureNetworkEvents`	`boolean`	`false`	Capture the full network event stream into the result. Default false (only the document event is captured). Native only.
`sessionAffinity`	`boolean`	`true`	Enable session affinity: reuse chromiumoxide Pages for same-domain requests so cookies + fingerprint + solved challenges persist. Default: true. When false, each request gets a fresh Page.

Methods

defaultOptions()

Signature:

public static BrowserConfig defaultOptions()

Example:

var result = BrowserConfig.defaultOptions();

Returns: BrowserConfig

BrowserExtras

Browser-specific extras populated when the native browser backend was used.

Available on ScrapeResult.browser when BrowserBackend.Native handled the request.

Field	Type	Default	Description
`evalResult`	`Optional<Object>`	`null`	Return value of `BrowserConfig.eval_script`, if provided.
`networkEvents`	`List<ResponseMeta>`	`Collections.emptyList()`	Network events captured during page navigation (only populated when `BrowserConfig.capture_network_events` is true).
`cookies`	`List<CookieInfo>`	`Collections.emptyList()`	All non-expired cookies present in the browser’s cookie jar after navigation completes (includes both prior cookies and server Set-Cookie).

CitationReference

A single numbered reference in a citation list — produced by the citation extractor when content uses inline [N]-style markers.

Field	Type	Default	Description
`index`	`long`	—	1-based reference number as it appears in the source text.
`url`	`String`	—	Resolved absolute URL for this reference.
`text`	`String`	—	Human-readable anchor text or title for the reference.

CitationResult

Result of citation conversion.

Field	Type	Default	Description
`content`	`String`	—	Markdown with links replaced by numbered citations.
`references`	`List<CitationReference>`	`Collections.emptyList()`	Numbered reference list: (index, url, text).

ContentConfig

Content extraction and conversion configuration.

Controls how HTML is converted to the output format. Uses html-to-markdown-rs as the conversion engine for all formats (markdown, plain text, djot).

Field	Type	Default	Description
`outputFormat`	`String`	`"markdown"`	Output format: `"markdown"` (default), `"plain"`, `"djot"`.
`preprocessingPreset`	`String`	`"standard"`	Preprocessing aggressiveness: `"minimal"`, `"standard"` (default), `"aggressive"`. - Minimal: only scripts/styles removed. - Standard: also removes nav, nav-hinted headers/footers/asides, forms. - Aggressive: removes all footers/asides unconditionally.
`removeNavigation`	`boolean`	`true`	Remove navigation elements (nav, breadcrumbs, menus). Default: `true`.
`removeForms`	`boolean`	`true`	Remove form elements. Default: `true`.
`stripTags`	`List<String>`	`Collections.emptyList()`	HTML tag names to strip (render children only, remove the tag wrapper). Default: `\["noscript"\]`.
`preserveTags`	`List<String>`	`Collections.emptyList()`	HTML tag names to preserve as raw HTML in output.
`excludeSelectors`	`List<String>`	`Collections.emptyList()`	CSS selectors for elements to exclude entirely (element + all content). Unlike `strip_tags` (which removes the wrapper but keeps children), excluded elements and all descendants are dropped. Supports CSS selectors: `.class`, `#id`, `\[attribute\]`, compound selectors. Example: `\[".cookie-banner", "#ad-container", "\[role='complementary'\]"\]`
`skipImages`	`boolean`	`false`	Skip image elements in output. Default: `false`.
`maxDepth`	`Optional<Long>`	`null`	Max DOM traversal depth. Prevents stack overflow on deeply nested HTML.
`wrap`	`boolean`	`false`	Enable line wrapping. Default: `false`.
`wrapWidth`	`long`	`80`	Wrap width when `wrap` is enabled. Default: `80`.
`includeDocumentStructure`	`boolean`	`true`	Include document structure tree in output. Default: `true`.

Methods

defaultOptions()

Signature:

public static ContentConfig defaultOptions()

Example:

var result = ContentConfig.defaultOptions();

Returns: ContentConfig

CookieInfo

Information about an HTTP cookie received from a response.

Field	Type	Default	Description
`name`	`String`	—	The cookie name.
`value`	`String`	—	The cookie value.
`domain`	`Optional<String>`	`null`	The cookie domain, if specified.
`path`	`Optional<String>`	`null`	The cookie path, if specified.

CrawlConfig

Configuration for crawl, scrape, and map operations.

Field	Type	Default	Description
`maxDepth`	`Optional<Long>`	`null`	Maximum crawl depth (number of link hops from the start URL).
`maxPages`	`Optional<Long>`	`null`	Maximum number of pages to crawl.
`maxLinksPerPage`	`Optional<Long>`	`null`	Maximum links enqueued from a single page. Defaults to 10000. Bounds the work one hostile or pathological page can create; links past the cap are dropped and a warning is logged.
`maxConcurrent`	`Optional<Long>`	`null`	Maximum number of concurrent requests.
`respectRobotsTxt`	`boolean`	`false`	Whether to respect robots.txt directives.
`softHttpErrors`	`boolean`	`false`	When true, HTTP-level error responses (404 NotFound, 403 Forbidden, WAF blocks) are surfaced as `ScrapeResult` records with the matching `status_code` rather than raised as `CrawlError`. Default `false` preserves the historical throw-on-error contract for direct fetches. Independently of this flag, 404s reached at the end of a redirect chain are always surfaced softly — the user opted into redirect-following, so receiving a 404 there is part of the normal flow rather than an unexpected error.
`userAgent`	`Optional<String>`	`null`	Custom user-agent string.
`stayOnDomain`	`boolean`	`false`	Whether to restrict crawling to the same domain.
`allowSubdomains`	`boolean`	`false`	Whether to allow subdomains when `stay_on_domain` is true.
`includePaths`	`List<String>`	`Collections.emptyList()`	Regex patterns for paths to include during crawling.
`excludePaths`	`List<String>`	`Collections.emptyList()`	Regex patterns for paths to exclude during crawling.
`customHeaders`	`Map<String, String>`	`Collections.emptyMap()`	Custom HTTP headers to send with each request.
`requestTimeout`	`Duration`	`30000ms`	Timeout for individual HTTP requests (in milliseconds when serialized).
`rateLimitMs`	`Optional<Long>`	`null`	Per-domain rate limit in milliseconds. When set, enforces a minimum delay between requests to the same domain. Defaults to 200ms when `null`.
`maxRedirects`	`long`	`10`	Maximum number of redirects to follow.
`retryCount`	`long`	`0`	Number of retry attempts for failed requests.
`retryCodes`	`List<Short>`	`Collections.emptyList()`	HTTP status codes that should trigger a retry.
`cookiesEnabled`	`boolean`	`false`	Whether to enable cookie handling.
`auth`	`Optional<AuthConfig>`	`null`	Authentication configuration.
`maxBodySize`	`Optional<Long>`	`null`	Maximum response body size in bytes.
`removeTags`	`List<String>`	`Collections.emptyList()`	CSS selectors for tags to remove from HTML before processing.
`content`	`ContentConfig`	—	Content extraction and conversion configuration.
`mapLimit`	`Optional<Long>`	`null`	Maximum number of URLs to return from a map operation.
`mapSearch`	`Optional<String>`	`null`	Search filter for map results (case-insensitive substring match on URLs).
`downloadAssets`	`boolean`	`false`	Whether to download assets (CSS, JS, images, etc.) from the page.
`assetTypes`	`List<AssetCategory>`	`Collections.emptyList()`	Filter for asset categories to download.
`maxAssetSize`	`Optional<Long>`	`null`	Maximum size in bytes for individual asset downloads.
`browser`	`BrowserConfig`	—	Browser configuration.
`proxy`	`Optional<ProxyConfig>`	`null`	Proxy configuration for HTTP requests.
`userAgents`	`List<String>`	`Collections.emptyList()`	List of user-agent strings for rotation. If non-empty, overrides `user_agent`.
`captureScreenshot`	`boolean`	`false`	Whether to capture a screenshot when using the browser. Only supported by `scrape()` with `BrowserBackend.Chromiumoxide` and `BrowserMode.Always` or `Stealth`. A screenshot is 100–500 KB of PNG per page, so `crawl()` does not carry screenshots in `CrawlPageResult`/`CrawlResult` at all — a multi-thousand-page crawl holding one per page in memory is not a safe default. Setting this with any other configuration (a different backend, `BrowserMode.Auto`/`Never`, or during `crawl()`) has no effect and logs a warning rather than silently doing nothing.
`followDocumentUrls`	`boolean`	`false`	Re-enqueue discovered `LinkType.Document` URLs into the crawl frontier so the crawl follows links from document pages (PDFs, etc.) as it would from HTML pages. Default: `false` (documents terminate at materialisation).
`documentUrlDepth`	`Optional<Integer>`	`null`	Maximum document-depth (from the seed URL through document links only) when `follow_document_urls` is true. `null` means inherit `max_depth`. Independent of `max_depth`: a document URL is enqueued only if BOTH the outer `max_depth` and (if set) `document_url_depth` permit it.
`downloadDocuments`	`boolean`	`true`	Whether to download non-HTML documents (PDF, DOCX, images, code, etc.) instead of skipping them. Defaults to `true` — unlike `download_assets` and `capture_screenshot`, which default to `false`.
`documentMaxSize`	`Optional<Long>`	`52428800`	Maximum size in bytes for document downloads. Defaults to 50 MB.
`documentMimeTypes`	`List<String>`	`Collections.emptyList()`	Allowlist of MIME types to download. If empty, uses built-in defaults.
`documentOutputDir`	`Optional<String>`	`null`	Directory to stream downloaded document bytes into instead of holding them in memory on `DownloadedDocument.content`. When set, `content` is left empty and `DownloadedDocument.content_path` is populated with `<dir>/<content_hash>.<ext>`. `null` (default) preserves today’s in-memory-only behavior. Has no effect on wasm32, which has no filesystem — use `document_content_encoding` there instead.
`documentContentEncoding`	`Optional<DocumentContentEncoding>`	`null`	Opt-in encoding that duplicates `DownloadedDocument.content` into a serializable field for language bindings that need the bytes in-memory (`content` itself is `alef(skip)`ed). `null` (default) means no encoding is produced. Independent of `document_output_dir` — set both to get a file on disk and an in-memory copy.
`warcOutput`	`Optional<String>`	`null`	Path to write WARC output. If `null`, WARC output is disabled.
`browserProfile`	`Optional<String>`	`null`	Named browser profile for persistent sessions (cookies, localStorage). Chromiumoxide backend only. The native backend runs an in-process JavaScript engine with no Chrome process and therefore no profile directory, so this is ignored there and logs a warning. It is also ignored — with a warning — when a shared browser pool is in use (the pool launches before any per-crawl config exists) or when connecting to an external CDP endpoint whose process crawlberg does not own.
`saveBrowserProfile`	`boolean`	`false`	Whether to save changes back to the browser profile on exit.
`ssrf`	`SsrfPolicy`	—	SSRF policy for outbound network requests. Default: deny private networks, allow http/https only, max 5 redirects. `deny_private`, `allowlist` and `max_redirects` are exposed to all language bindings. `scheme_allowlist` stays Rust-only — see `SsrfPolicy`. wasm32 (including Node.js): `deny_private` does not stop hostname-based requests. There is no DNS resolution on this target, so only a literal IP host is checked against the policy — a domain name is always permitted, regardless of `deny_private`. Under Node, where `fetch` enforces no CORS, this means a service embedding the wasm binding can be driven to internal hosts by domain name even with `deny_private = true`. Enforce egress restrictions at the network layer for that deployment target; do not rely on this field. See `crawlberg.net.validate_url`.
`ssrfDenyPrivateExplicit`	`Optional<Boolean>`	`null`	Pins `SsrfPolicy.deny_private` to a caller-chosen value, bypassing the `CRAWLBERG_ALLOW_PRIVATE_NETWORK` operator override entirely for this config. `ssrf.deny_private` is a plain, always-serialized `bool`: several alef-generated bindings construct `SsrfPolicy.default()` (hardcoding `deny_private: true`) whenever their caller never touches SSRF settings at all, so `true` on that field alone cannot distinguish “the caller wants private networks denied” from “the binding’s own structural default landed on `true`”. The environment variable exists precisely to resolve that ambiguity in the common case by treating any `true` as inconclusive and deferring to the operator. Set this field when that default-deferral is wrong for your call — e.g. a test that must prove `deny_private: true` still denies even while the operator has set `CRAWLBERG_ALLOW_PRIVATE_NETWORK` suite-wide for every other call. `null` (default) preserves today’s behavior: the environment variable may still flip `ssrf.deny_private` to `false`. `Some(value)` pins `ssrf.deny_private` to `value` and the environment variable is not consulted for this config.

Methods

defaultOptions()

Signature:

public static CrawlConfig defaultOptions()

Example:

var result = CrawlConfig.defaultOptions();

Returns: CrawlConfig

validate()

Validate the configuration, returning an error if any values are invalid.

Signature:

public void validate() throws CrawlError

Example:

instance.validate();

Returns: No return value.

Errors: Throws CrawlErrorException.

CrawlEngineHandle

Opaque handle to a configured crawl engine.

Constructed via create_engine with an optional CrawlConfig. Default implementations for all pluggable components are used internally.

CrawlPageResult

The result of crawling a single page during a crawl operation.

Field	Type	Default	Description
`url`	`String`	—	The original URL of the page.
`normalizedUrl`	`String`	—	The normalized URL of the page.
`statusCode`	`short`	—	The HTTP status code of the response.
`contentType`	`String`	—	The Content-Type header value.
`html`	`String`	—	The HTML body of the response.
`bodySize`	`long`	—	The size of the response body in bytes.
`metadata`	`PageMetadata`	—	Extracted metadata from the page.
`links`	`List<LinkInfo>`	`Collections.emptyList()`	Links found on the page.
`images`	`List<ImageInfo>`	`Collections.emptyList()`	Images found on the page.
`feeds`	`List<FeedInfo>`	`Collections.emptyList()`	Feed links found on the page.
`jsonLd`	`List<JsonLdEntry>`	`Collections.emptyList()`	JSON-LD entries found on the page.
`depth`	`long`	—	The depth of this page from the start URL.
`stayedOnDomain`	`boolean`	—	Whether this page is on the same domain as the start URL.
`wasSkipped`	`boolean`	—	Whether this page was skipped (binary or PDF content).
`isPdf`	`boolean`	—	Whether the content is a PDF.
`detectedCharset`	`Optional<String>`	`null`	The detected character set encoding.
`markdown`	`Optional<MarkdownResult>`	`null`	Markdown conversion of the page content.
`extractedData`	`Optional<Object>`	`null`	Structured data extracted by LLM. Populated when extraction is configured.
`extractionMeta`	`Optional<ExtractionMeta>`	`null`	Metadata about the LLM extraction pass (cost, tokens, model).
`downloadedDocument`	`Optional<DownloadedDocument>`	`null`	Downloaded non-HTML document (PDF, DOCX, image, code, etc.).
`browserUsed`	`boolean`	—	Whether the browser fallback was used to fetch this page.

CrawlResult

The result of a multi-page crawl operation.

Field	Type	Default	Description
`pages`	`List<CrawlPageResult>`	`Collections.emptyList()`	The list of crawled pages.
`finalUrl`	`String`	—	The final URL after following redirects.
`redirectCount`	`long`	—	The number of redirects followed.
`wasSkipped`	`boolean`	—	Whether any page was skipped during crawling.
`error`	`Optional<String>`	`null`	An error message, if the crawl encountered an issue.
`cookies`	`List<CookieInfo>`	`Collections.emptyList()`	Cookies collected during the crawl.
`stayedOnDomain`	`boolean`	—	Whether all crawled pages stayed on the same domain as the start URL.
`browserUsed`	`boolean`	—	Whether the browser fallback was used for any page in this crawl.

Methods

uniqueNormalizedUrls()

Returns the count of unique normalized URLs encountered during crawling.

Computed from pages (not the deprecated normalized_urls field) so it is correct across every binding that reconstructs CrawlResult from pages alone. In streaming mode pages is empty, so this returns 0 on the opaque-handle (C/Go/C#/Zig/Dart) path where it previously counted streamed pages — a known, accepted cost of making the other ten binding families correct.

Signature:

public long uniqueNormalizedUrls()

Example:

var result = instance.uniqueNormalizedUrls();

Returns: long

CrawlStreamRequest

Request to begin a single-URL streaming crawl.

Wraps a single seed URL for delivery through the streaming-adapter binding surface. Required as a struct because alef’s streaming adapter requires a named request type — primitives are not supported.

Field	Type	Default	Description
`url`	`String`	—	The seed URL to crawl.

DownloadedAsset

A downloaded asset from a page.

Field	Type	Default	Description
`url`	`String`	—	The original URL of the asset.
`contentHash`	`String`	—	The SHA-256 content hash of the asset.
`mimeType`	`Optional<String>`	`null`	The MIME type from the Content-Type header.
`size`	`long`	—	The size of the asset in bytes.
`assetCategory`	`AssetCategory`	`AssetCategory.IMAGE`	The category of the asset.
`htmlTag`	`Optional<String>`	`null`	The HTML tag that referenced this asset (e.g., “link”, “script”, “img”).

DownloadedDocument

A downloaded non-HTML document (PDF, DOCX, image, code file, etc.).

When the crawler encounters non-HTML content and download_documents is enabled, it downloads the raw bytes and populates this struct instead of skipping the resource.

Field	Type	Default	Description
`url`	`String`	—	The URL the document was fetched from.
`mimeType`	`String`	—	The MIME type from the Content-Type header.
`size`	`long`	—	Size of the document in bytes.
`filename`	`Optional<String>`	`null`	Filename extracted from Content-Disposition or URL path.
`contentHash`	`String`	—	SHA-256 hex digest of the content.
`headers`	`Map<String, String>`	`Collections.emptyMap()`	Selected response headers.
`truncated`	`boolean`	—	True when `content` (or the file at `content_path`) was truncated to `document_max_size`; `size` still reports the original, untruncated length.
`contentPath`	`Optional<String>`	`null`	Filesystem path the document was streamed to when `document_output_dir` was set. `content` is empty in memory when this is populated.
`contentBase64`	`Optional<String>`	`null`	Base64-encoded copy of `content`, populated only when `document_content_encoding` was set to `Base64`.

ExtractionMeta

Metadata about an LLM extraction pass.

Field	Type	Default	Description
`cost`	`Optional<Double>`	`null`	Estimated cost of the LLM call in USD.
`promptTokens`	`Optional<Long>`	`null`	Number of prompt (input) tokens consumed.
`completionTokens`	`Optional<Long>`	`null`	Number of completion (output) tokens generated.
`model`	`Optional<String>`	`null`	The model identifier used for extraction.
`chunksProcessed`	`long`	—	Number of content chunks sent to the LLM.

FaviconInfo

Information about a favicon or icon link.

Field	Type	Default	Description
`url`	`String`	—	The icon URL.
`rel`	`String`	—	The `rel` attribute (e.g., “icon”, “apple-touch-icon”).
`sizes`	`Optional<String>`	`null`	The `sizes` attribute, if present.
`mimeType`	`Optional<String>`	`null`	The MIME type, if present.

FeedInfo

Information about a feed link found on a page.

Field	Type	Default	Description
`url`	`String`	—	The feed URL.
`title`	`Optional<String>`	`null`	The feed title, if present.
`feedType`	`FeedType`	`FeedType.RSS`	The type of feed.

HeadingInfo

A heading element extracted from the page.

Field	Type	Default	Description
`level`	`byte`	—	The heading level (1-6).
`text`	`String`	—	The heading text content.

HreflangEntry

An hreflang alternate link entry.

Field	Type	Default	Description
`lang`	`String`	—	The language code (e.g., “en”, “fr”, “x-default”).
`url`	`String`	—	The URL for this language variant.

ImageInfo

Information about an image found on a page.

Field	Type	Default	Description
`url`	`String`	—	The image URL.
`alt`	`Optional<String>`	`null`	The alt text, if present.
`width`	`Optional<Integer>`	`null`	The width attribute, if present and parseable.
`height`	`Optional<Integer>`	`null`	The height attribute, if present and parseable.
`source`	`ImageSource`	`ImageSource.IMG`	The source of the image reference.

InteractionResult

Result of executing a sequence of page interaction actions.

Field	Type	Default	Description
`actionResults`	`List<ActionResult>`	`Collections.emptyList()`	Results from each executed action.
`finalHtml`	`String`	—	Final page HTML after all actions completed.
`finalUrl`	`String`	—	Final page URL (may have changed due to navigation).
`screenshotBase64`	`Optional<String>`	`null`	Base64-encoded PNG screenshot taken after all actions. Populated only when a `PageAction.Screenshot` action actually ran, so callers that never request a screenshot do not pay the encoding cost.

JsonLdEntry

A JSON-LD structured data entry found on a page.

Field	Type	Default	Description
`schemaType`	`String`	—	The `@type` value from the JSON-LD object.
`name`	`Optional<String>`	`null`	The `name` value, if present.
`raw`	`String`	—	The raw JSON-LD string.

LinkInfo

Information about a link found on a page.

Field	Type	Default	Description
`url`	`String`	—	The resolved URL of the link.
`text`	`String`	—	The visible text of the link.
`linkType`	`LinkType`	`LinkType.INTERNAL`	The classification of the link.
`rel`	`Optional<String>`	`null`	The `rel` attribute value, if present.
`nofollow`	`boolean`	—	Whether the link has `rel="nofollow"`.

MapResult

The result of a map operation, containing discovered URLs.

Field	Type	Default	Description
`urls`	`List<SitemapUrl>`	`Collections.emptyList()`	The list of discovered URLs.

MarkdownResult

Rich markdown conversion result from HTML processing.

Field	Type	Default	Description
`content`	`String`	—	Converted markdown text.
`documentStructure`	`Optional<Object>`	`null`	Structured document tree with semantic nodes.
`tables`	`List<Object>`	`Collections.emptyList()`	Extracted tables with structured cell data.
`warnings`	`List<String>`	`Collections.emptyList()`	Non-fatal processing warnings.
`citations`	`boolean`	—	Whether citation conversion was applied and produced at least one reference. `true` when the markdown contained inline links that were converted to numbered citation references. The converted content (with `\[N\]` markers) is available in `content`; the full reference list is accessible via `generate_citations` if needed separately.
`fitContent`	`Optional<String>`	`null`	Content-filtered markdown optimized for LLM consumption.

PageMetadata

Metadata extracted from an HTML page’s <meta> tags and <title> element.

Field	Type	Default	Description
`title`	`Optional<String>`	`null`	The page title from the `<title>` element.
`description`	`Optional<String>`	`null`	The meta description.
`canonicalUrl`	`Optional<String>`	`null`	The canonical URL from `<link rel="canonical">`.
`keywords`	`Optional<String>`	`null`	Keywords from `<meta name="keywords">`.
`author`	`Optional<String>`	`null`	Author from `<meta name="author">`.
`viewport`	`Optional<String>`	`null`	Viewport content from `<meta name="viewport">`.
`themeColor`	`Optional<String>`	`null`	Theme color from `<meta name="theme-color">`.
`generator`	`Optional<String>`	`null`	Generator from `<meta name="generator">`.
`robots`	`Optional<String>`	`null`	Robots content from `<meta name="robots">`.
`htmlLang`	`Optional<String>`	`null`	The `lang` attribute from the `<html>` element.
`htmlDir`	`Optional<String>`	`null`	The `dir` attribute from the `<html>` element.
`ogTitle`	`Optional<String>`	`null`	Open Graph title.
`ogType`	`Optional<String>`	`null`	Open Graph type.
`ogImage`	`Optional<String>`	`null`	Open Graph image URL.
`ogDescription`	`Optional<String>`	`null`	Open Graph description.
`ogUrl`	`Optional<String>`	`null`	Open Graph URL.
`ogSiteName`	`Optional<String>`	`null`	Open Graph site name.
`ogLocale`	`Optional<String>`	`null`	Open Graph locale.
`ogVideo`	`Optional<String>`	`null`	Open Graph video URL.
`ogAudio`	`Optional<String>`	`null`	Open Graph audio URL.
`ogLocaleAlternates`	`Optional<List<String>>`	`Collections.emptyList()`	Open Graph locale alternates.
`twitterCard`	`Optional<String>`	`null`	Twitter card type.
`twitterTitle`	`Optional<String>`	`null`	Twitter title.
`twitterDescription`	`Optional<String>`	`null`	Twitter description.
`twitterImage`	`Optional<String>`	`null`	Twitter image URL.
`twitterSite`	`Optional<String>`	`null`	Twitter site handle.
`twitterCreator`	`Optional<String>`	`null`	Twitter creator handle.
`dcTitle`	`Optional<String>`	`null`	Dublin Core title.
`dcCreator`	`Optional<String>`	`null`	Dublin Core creator.
`dcSubject`	`Optional<String>`	`null`	Dublin Core subject.
`dcDescription`	`Optional<String>`	`null`	Dublin Core description.
`dcPublisher`	`Optional<String>`	`null`	Dublin Core publisher.
`dcDate`	`Optional<String>`	`null`	Dublin Core date.
`dcType`	`Optional<String>`	`null`	Dublin Core type.
`dcFormat`	`Optional<String>`	`null`	Dublin Core format.
`dcIdentifier`	`Optional<String>`	`null`	Dublin Core identifier.
`dcLanguage`	`Optional<String>`	`null`	Dublin Core language.
`dcRights`	`Optional<String>`	`null`	Dublin Core rights.
`article`	`Optional<ArticleMetadata>`	`null`	Article metadata from `article:*` Open Graph tags.
`hreflangs`	`Optional<List<HreflangEntry>>`	`Collections.emptyList()`	Hreflang alternate links.
`favicons`	`Optional<List<FaviconInfo>>`	`Collections.emptyList()`	Favicon and icon links.
`headings`	`Optional<List<HeadingInfo>>`	`Collections.emptyList()`	Heading elements (h1-h6).
`wordCount`	`Optional<Long>`	`null`	Computed word count of the page body text.

ProxyConfig

Proxy configuration for HTTP requests.

Field	Type	Default	Description
`url`	`String`	—	Proxy URL (e.g. “http://proxy:8080", “socks5://proxy:1080”).
`username`	`Optional<String>`	`null`	Optional username for proxy authentication.
`password`	`Optional<String>`	`null`	Optional password for proxy authentication.

ResponseMeta

Response metadata extracted from HTTP headers.

Field	Type	Default	Description
`etag`	`Optional<String>`	`null`	The ETag header value.
`lastModified`	`Optional<String>`	`null`	The Last-Modified header value.
`cacheControl`	`Optional<String>`	`null`	The Cache-Control header value.
`server`	`Optional<String>`	`null`	The Server header value.
`xPoweredBy`	`Optional<String>`	`null`	The X-Powered-By header value.
`contentLanguage`	`Optional<String>`	`null`	The Content-Language header value.
`contentEncoding`	`Optional<String>`	`null`	The Content-Encoding header value.

ScrapeResult

The result of a single-page scrape operation.

Field	Type	Default	Description
`statusCode`	`short`	—	The HTTP status code of the response.
`finalUrl`	`String`	—	The final URL after following all redirects.
`contentType`	`String`	—	The Content-Type header value.
`html`	`String`	—	The HTML body of the response.
`bodySize`	`long`	—	The size of the response body in bytes.
`metadata`	`PageMetadata`	—	Extracted metadata from the page.
`links`	`List<LinkInfo>`	`Collections.emptyList()`	Links found on the page.
`images`	`List<ImageInfo>`	`Collections.emptyList()`	Images found on the page.
`feeds`	`List<FeedInfo>`	`Collections.emptyList()`	Feed links found on the page.
`jsonLd`	`List<JsonLdEntry>`	`Collections.emptyList()`	JSON-LD entries found on the page.
`isAllowed`	`boolean`	—	Whether the URL is allowed by robots.txt.
`crawlDelay`	`Optional<Long>`	`null`	The crawl delay from robots.txt, in seconds.
`noindexDetected`	`boolean`	—	Whether a noindex directive was detected.
`nofollowDetected`	`boolean`	—	Whether a nofollow directive was detected.
`xRobotsTag`	`Optional<String>`	`null`	The X-Robots-Tag header value, if present.
`isPdf`	`boolean`	—	Whether the content is a PDF.
`wasSkipped`	`boolean`	—	Whether the page was skipped (binary or PDF content).
`detectedCharset`	`Optional<String>`	`null`	The detected character set encoding.
`authHeaderSent`	`boolean`	—	Whether an authentication header was sent with the request.
`responseMeta`	`Optional<ResponseMeta>`	`null`	Response metadata extracted from HTTP headers.
`assets`	`List<DownloadedAsset>`	`Collections.emptyList()`	Downloaded assets from the page.
`jsRenderHint`	`boolean`	—	Whether the page content suggests JavaScript rendering is needed.
`browserUsed`	`boolean`	—	Whether the browser fallback was used to fetch this page.
`markdown`	`Optional<MarkdownResult>`	`null`	Markdown conversion of the page content.
`extractedData`	`Optional<Object>`	`null`	Structured data extracted by LLM. Populated when extraction is configured.
`extractionMeta`	`Optional<ExtractionMeta>`	`null`	Metadata about the LLM extraction pass (cost, tokens, model).
`screenshotBase64`	`Optional<String>`	`null`	Base64-encoded PNG screenshot of the page. Populated only when `CrawlConfig.capture_screenshot` was enabled for this request, so callers that never requested a screenshot do not pay the encoding cost.
`downloadedDocument`	`Optional<DownloadedDocument>`	`null`	Downloaded non-HTML document (PDF, DOCX, image, code, etc.).
`browser`	`Optional<BrowserExtras>`	`null`	Browser-specific extras (eval result, network events, cookies). Only populated when `BrowserBackend.Native` was used for this request.

SitemapUrl

A URL entry from a sitemap.

Field	Type	Default	Description
`url`	`String`	—	The URL.
`lastmod`	`Optional<String>`	`null`	The last modification date, if present.
`changefreq`	`Optional<String>`	`null`	The change frequency, if present.
`priority`	`Optional<String>`	`null`	The priority, if present.

SsrfPolicy

SSRF policy configuration.

Field	Type	Default	Description
`denyPrivate`	`boolean`	`true`	If true, reject URLs that resolve to private/metadata IP ranges.
`allowlist`	`List<HostMatcher>`	`Collections.emptyList()`	Hostnames and IP ranges permitted regardless of `deny_private`. The allowlist is an override of `deny_private`, not an intersection with it. Precedence, in order: 1. `deny_private == false` permits everything; the allowlist is not consulted. 2. A hostname matching an `Exact` or `Suffix` entry is permitted immediately, before DNS resolution — so the deny-list is never applied to it. This trusts the host string: a name that resolves into private space is still permitted. 3. A literal or resolved IP inside a `Cidr` entry is permitted even though it is in the default deny-list. 4. Otherwise the default deny-list decides. An empty allowlist therefore denies nothing by itself — it simply leaves `deny_private` and the deny-list in sole control.
`maxRedirects`	`byte`	`5`	Maximum number of HTTP redirects to follow during validation.

Methods

defaultOptions()

Signature:

public static SsrfPolicy defaultOptions()

Example:

var result = SsrfPolicy.defaultOptions();

Returns: SsrfPolicy

fromEnv()

Create a policy from environment variables.

On native platforms, reads CRAWLBERG_ALLOW_PRIVATE_NETWORK — if set to “1” or “true” (case-insensitive), sets deny_private = false. Otherwise, defaults to deny_private = true.

On wasm32 targets (browser/Node.js), environment variables are not accessible to the compiled module. Defaults to deny_private = false because:

Outbound requests in a browser go through the fetch API, which enforces its own network policies.
Rust-side SSRF checking is unenforceable and redundant in a wasm32 context.
For testing and localhost access, the host’s network sandbox is the enforcing boundary.

Node.js caveat: deny_private (whatever its value) has no effect on hostname-based requests under wasm32. There is no DNS resolution on this target, so validate_url only ever checks a literal IP host; a domain name falls straight through to Ok(()). In a browser this is covered by same-origin/CORS. Node’s fetch enforces no CORS, so a Node service embedding this wasm module can be driven to internal hosts by domain name even though deny_private = true. Do not rely on this policy to stop that in Node — enforce egress restrictions (network policy, firewall, proxy allowlist) outside the process.

Signature:

public static SsrfPolicy fromEnv()

Example:

var result = SsrfPolicy.fromEnv();

Returns: SsrfPolicy

Enums

BrowserMode

When to use the headless browser fallback.

Value	Description
`AUTO`	Automatically detect when JS rendering is needed and fall back to browser.
`ALWAYS`	Always use the browser for every request.
`NEVER`	Never use the browser fallback.
`STEALTH`	Always use the browser with all stealth surfaces enabled. Behaves like `Always` for escalation purposes (every request is routed through the browser tier), but additionally enables: - browser JavaScript stealth patches - native-backend TLS fingerprint spoofing - stealth-aware default user-agent when no explicit UA is set - 1920×1080 viewport override Use this instead of setting the now-removed `BrowserConfig.stealth` boolean field.

BrowserWait

Wait strategy for browser page rendering.

Value	Description
`NETWORK_IDLE`	Wait until network activity is idle.
`SELECTOR`	Wait for a specific CSS selector to appear in the DOM.
`FIXED`	Wait for a fixed duration after navigation.

BrowserBackend

Browser backend used for JavaScript rendering.

Value	Description
`CHROMIUMOXIDE`	Existing Chromium/CDP backend powered by chromiumoxide.
`NATIVE`	Crawlberg-owned native browser backend derived from Obscura.

DocumentContentEncoding

Opt-in encoding applied to a downloaded document’s bytes for callers who need the content available in a serializable field rather than reading it from disk.

null (the CrawlConfig.document_content_encoding default) produces neither — unlike screenshots, base64-encoding a document by default would duplicate an already up-to-document_max_size buffer (50 MB default) in memory per document.

Value	Description
`BASE64`	Populate `DownloadedDocument.content_base64` with a base64-encoded copy.

AuthConfig

Authentication configuration.

Value	Description
`BASIC`	HTTP Basic authentication. — Fields: `username`: `String`, `password`: `String`
`BEARER`	Bearer token authentication. — Fields: `token`: `String`
`HEADER`	Custom authentication header. — Fields: `name`: `String`, `value`: `String`

LinkType

The classification of a link.

Value	Description
`INTERNAL`	A link to the same domain.
`EXTERNAL`	A link to a different domain.
`ANCHOR`	A fragment-only link (e.g., `#section`).
`DOCUMENT`	A link to a downloadable document (PDF, DOC, etc.).

ImageSource

The source of an image reference.

Value	Description
`IMG`	An `<img>` tag.
`PICTURE_SOURCE`	A `<source>` tag inside `<picture>`.
`OG_IMAGE`	An `og:image` meta tag.
`TWITTER_IMAGE`	A `twitter:image` meta tag.

FeedType

The type of a feed (RSS, Atom, or JSON Feed).

Value	Description
`RSS`	RSS feed.
`ATOM`	Atom feed.
`JSON_FEED`	JSON Feed.

AssetCategory

The category of a downloaded asset.

Value	Description
`DOCUMENT`	A document file (PDF, DOC, etc.).
`IMAGE`	An image file.
`AUDIO`	An audio file.
`VIDEO`	A video file.
`FONT`	A font file.
`STYLESHEET`	A CSS stylesheet.
`SCRIPT`	A JavaScript file.
`ARCHIVE`	An archive file (ZIP, TAR, etc.).
`DATA`	A data file (JSON, XML, CSV, etc.).
`OTHER`	An unrecognized asset type.

CrawlEvent

An event emitted during a streaming crawl operation.

Not available on wasm32 targets — streaming requires native concurrency primitives (tokio channels, JoinSet) that are not supported on wasm32.

Delivered to bindings through each target’s native streaming idiom.

Value	Description
`PAGE`	A single page has been crawled. — Fields: `result`: `CrawlPageResult`
`ERROR`	An error occurred while crawling a URL. — Fields: `url`: `String`, `error`: `String`
`COMPLETE`	The crawl has completed. — Fields: `pagesCrawled`: `long`

PageAction

A single page interaction action.

Actions are serialized with a type tag using camelCase naming, except ExecuteJs which is explicitly renamed to "executeJs".

Value	Description
`CLICK`	Click on an element matching the given CSS selector. — Fields: `selector`: `String`
`TYPE_TEXT`	Type text into an element matching the given CSS selector. — Fields: `selector`: `String`, `text`: `String`
`PRESS`	Press a keyboard key (e.g. “Enter”, “Tab”, “Escape”). — Fields: `key`: `String`
`SCROLL`	Scroll the page or a specific element. — Fields: `direction`: `ScrollDirection`, `selector`: `String`, `amount`: `long`
`WAIT`	Wait for a duration or for an element to appear. — Fields: `milliseconds`: `long`, `selector`: `String`
`SCREENSHOT`	Take a screenshot of the current page. — Fields: `fullPage`: `boolean`
`EXECUTE_JS`	Execute arbitrary JavaScript in the page context. Safety: The script runs with full page privileges in the browser context. Only execute scripts from trusted sources. — Fields: `script`: `String`
`SCRAPE`	Scrape the current page HTML.

ScrollDirection

Direction for a scroll action.

Value	Description
`UP`	Scroll upward.
`DOWN`	Scroll downward.

HostMatcher

Hostname/IP allowlist matcher for SSRF policy.

Serializes as an internally-tagged object so each variant is distinguishable on the wire and round-trips losslessly:

{"type": "exact",  "value": "api.example.com"}
{"type": "suffix", "value": ".example.com"}
{"type": "cidr",   "value": "10.0.0.0/8"}

A bare JSON string is still accepted on deserialization and resolves to Exact, preserving configs written against the previous untagged representation.

Exact: HostMatcher.Exact

Value	Description
`EXACT`	Exact hostname match (case-insensitive). — Fields: `value`: `String`
`SUFFIX`	Suffix match: “.xberg.io” matches “api.xberg.io” and “xberg.io”. — Fields: `value`: `String`
`CIDR`	CIDR match: “10.0.0.0/8” matches IP addresses in that range. — Fields: `value`: `String`

Errors

CrawlError

Errors that can occur during crawling, scraping, or mapping operations.

Variant	Description
`NOT_FOUND`	The requested page was not found (HTTP 404).
`UNAUTHORIZED`	The request was unauthorized (HTTP 401).
`FORBIDDEN`	The request was forbidden (HTTP 403).
`WAF_BLOCKED`	The request was blocked by a WAF or bot protection (HTTP 403 with WAF indicators). `vendor` is the lowercase identifier of the detected WAF (e.g. “cloudflare”, “datadome”). When the engine cannot identify the vendor, it uses “unknown”. `message` is the freeform description for logs and human readers. The stable error tag remains `forbidden: waf/blocked: MESSAGE` so existing log-grep patterns and cross-language bindings continue to work; vendor is surfaced separately for structured consumers.
`TIMEOUT`	The request timed out.
`RATE_LIMITED`	The request was rate-limited (HTTP 429).
`SERVER_ERROR`	A server error occurred (HTTP 5xx).
`BAD_GATEWAY`	A bad gateway error occurred (HTTP 502).
`GONE`	The resource is permanently gone (HTTP 410).
`CONNECTION`	A connection error occurred.
`DNS`	A DNS resolution error occurred.
`SSL`	An SSL/TLS error occurred.
`DATA_LOSS`	Data was lost or truncated during transfer.
`BROWSER_ERROR`	The browser failed to launch, connect, or navigate.
`BROWSER_TIMEOUT`	The browser page load or rendering timed out.
`INVALID_CONFIG`	The provided configuration is invalid.
`UNSUPPORTED`	The requested capability is not supported by the active backend or build.
`SSRF_POLICY_VIOLATION`	A URL was rejected by SSRF policy (private IP, metadata, disallowed scheme, etc).
`OTHER`	An unclassified error occurred.

SsrfError

SSRF validation error.

Variant	Description
`DENIED_BY_POLICY`	URL denied by SSRF policy: private IP, metadata IP, etc.
`NOT_ON_ALLOWLIST`	Host not on allowlist when an allowlist is configured.
`INVALID_CIDR`	Allowlist entry is not a parseable CIDR block.
`DNS_RESOLUTION_FAILED`	DNS resolution failed for hostname.
`INVALID_URL`	Invalid URL format.
`DISALLOWED_SCHEME`	URL scheme not in allowlist (e.g., `ftp://` when only `http`/`https` allowed).
`TOO_MANY_REDIRECTS`	Too many HTTP redirects encountered during validation.