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screenshot [url]

Take a screenshot of a specified element from an <html> document.



The url for the request. (type: string)



Used to append the results from a previous stage to the current stage. (provide a label, stage index, or boolean true to append the previous results)


array of JSON encoded values to pass to expression as input


background color in either RGB or HEX format including transparent


base64 encoded variant of image NOTE: large images (ie., body selector) can significantly increase JSON payload sizes


A boolean value of true/false that determines whether or not to use the cache. Generally most commands will default to true.


Format: "{CHECKPOINT NAME}:{COLUMN}" Used to store the value of the provided column (in the first row of results) in the provided name for use as a checkpoint in scheduled queries or other stages. Can be accessed using $CHECKPOINTS.{CHECKPOINT NAME}$


JSON serialized Cookie values to set pre-request


device to emulate, see devices command


css selector engine; "dom" or "jquery"


Enriches each result row with the previous row. The previous columns will be appended with a _previous.


javascript expression to evaluate after completion ES6 fat-arrow format with an argument of data passed (example "(data)=>>item.innerText)")


A filter to run on the command results before completing the command. If not provided, no filter is run on the results.


Starts the stage as if it was a fresh query, so will not use any previous result.


Adds a populated random guid column.


JSON header values to set pre-request


inject jquery library in last object argument passed to expression (example "(data, { $ })=>$('a').html()


Used to label a stage with a user provided label.


JSON sessionStorage values to set pre-request


inject lodash library in last object argument passed to expression (example "(data, { })=>)


inject mathjs library in last object argument passed to expression (example "(data, { mathjs })=>mathjs)


Override for the system max concurrent workers for a stage.


The URI for a http, https, socks(v5), socks5, socks4, or pac proxy


quality of the image from 0-100 for jpg images only


Randomizes the stage hash, even if args and flags are the same.


number attempts to sucessfully run the following task


CSS selector expression


capture session information; cookieStorage, localStorage and sessionStorage


JSON serialized sessionStorage values to set pre-request


Controls if a stats calculation is run on a stage after it completes.


A comma separated list of columns to include in the command results. If not provided, all columns will be included.


Each command has a default type, either "mapping" or "reducing". Some commands can operate as either, when "reducing" they will operate on all rows at once, when "mapping", they will operate on one row at a time.


device viewport height in pixels


device viewport width in pixels


Will rerun the stage until the provided expression is valid for the first line of results.