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WARNING: this can be an incredibly expensive and slow operation if you do not specify any filter criteria. Therefore we recommend that you always include objectIds and/or whereClause parameters.
HTTP Callout API
The callout API is available for making HTTP(S) requests from the Pulsar platform and returning results to the HTML and javascript. Since custom HTML/javascript code is hosted as a local file within Pulsar, there can be issues using the normal XMLHttpRequest (XHR) or fetch methods to issue Cross-Origin requests to external services. This Pulsar API helps sidestep those problems.