Reports - Preview HTML
Endpoint
/i/reports/preview
Overview
Generates report output and returns preview as raw HTML.
Authentication
Pass api_key or auth_token as a query parameter, or send countly-token as a header. See Authentication.
Permissions
Requires reports Read permission.
Request Parameters
| Parameter | Type | Required | Description |
|---|---|---|---|
api_key | String | Conditional | Required if auth_token is not provided. |
auth_token | String | Conditional | Required if api_key is not provided. |
app_id | String | Yes | App ID used by permission validation. |
args | String (JSON Object) | Yes | Must include report _id. |
args._id | String | Yes | Target report ID. |
Examples
Preview one report as HTML
/i/reports/preview?
api_key=YOUR_API_KEY&
app_id=6991c75b024cb89cdc04efd2&
args={"_id":"6262742dbf7392a8bfd8c1f6"}
Response
Success Response
Raw HTML response with headers:
Content-Type: text/html; charset=utf-8
Access-Control-Allow-Origin: *
<!DOCTYPE html>
<html>...</html>
Response Fields
| Field | Type | Description |
|---|---|---|
(response body) | String (HTML) | Full rendered report HTML payload. |
Content-Type | Header | text/html; charset=utf-8 |
Access-Control-Allow-Origin | Header | * |
Error Responses
200
{
"result": "Not enough args"
}
200
{
"result": "Report not found"
}
200
{
"result": "No data to report"
}
200
{
"result": "Error while generating report"
}
Standard authentication/authorization errors from read validation can also be returned.
Behavior
- Parses
argsJSON before route execution. - Uses owner-scoped lookup for non-global-admin users.
- Loads the target report and builds report HTML preview data.
- For non-core report types, renders HTML from
res.message.templateandres.message.datavia EJS. - Returns raw HTML response body (not wrapped JSON on success).
Limitations
- Successful response is HTML, not JSON.
- Preview generation executes full report query/render logic; large reports can take noticeable time.
Related Endpoints
Implementation details
Configuration Impact
| Setting | Default | Affects | User-visible impact |
|---|---|---|---|
api.offline_mode | false | Report enrichment during report generation | When enabled, external news/universe enrichment is skipped, so preview content can differ from online mode. |
Database Collections
| Collection | Used for | Data touched by this endpoint |
|---|---|---|
countly.reports | Report source | Reads target report definition. |
countly.members | Report generation context | Read indirectly by report generation flow. |
countly.event_groups | Report enrichment | Read indirectly for event-group metadata in generated report content. |