Evidence PostHog Source Plugin

Install this plugin in an Evidence app with

npm install evidence-connector-posthog

Register the plugin in your project in your evidence.plugins.yaml file with

datasources:
  evidence-connector-posthog: {}

Launch the development server with npm run dev and navigate to the settings menu (localhost:3000/settings) to add a data source using this plugin.

Source Options

| Option | Description | | --------- | -------------------------------------------------------------------------- | | appHost | Base URL of your PostHog instance for private endpoints. | | projectId | ID of the PostHog project you're trying to query data from. | | apiKey | API key with access to the project and Read access to Insight/Query scope. |

Source Queries

Source queries can be configured in two formats: .sql and .insight.

HogQL queries

Create a .sql file using HogQL syntax:

my_source_query_with_hogql.sql

SELECT toDate(timestamp) AS timestamp, count() AS event_count
FROM events
GROUP BY timestamp
LIMIT 100

Insights

Create a .insight file containing either a numeric id or alphanumeric short_id. Numeric IDs are preferred for cleaner API responses. Note: Only SQL-type insights are supported.

The file can contain either format:

my_source_query_with_insight_id.insight

1234567

or my_source_query_with_insight_short_id.insight

AbcdE0FG

Each insight has both types of ID, which can be found in different ways:

• The short_id appears in the URL when viewing the insight in PostHog (e.g. AbcdE0FG in https://us.posthog.com/project/00000/insights/AbcdE0FG)
• The id can only be retrieved through the API using the short_id:

export POSTHOG_PERSONAL_API_KEY=<POSTHOG_PERSONAL_API_KEY>
export POSTHOG_PROJECT_ID=<POSTHOG_PROJECT_ID>
curl \
    -H "Authorization: Bearer $POSTHOG_PERSONAL_API_KEY" \
    <ph_app_host>/api/projects/$POSTHOG_PROJECT_ID/insights/?short_id=<YOUR_INSIGHT_SHORT_ID>

PostHog Configuration

You will need to create a personal API key to access the Query and/or Insights endpoints.

You can create one in Settings > User > Personal API keys.

Make sure to include the project specified in your data source config under Organization & project access, and choose the query:read and/or insight:read scopes for the API key.

To learn more, see PostHog's API documentation.