The GCS connector exposes objects in a Google Cloud Storage bucket as datasets. Summation reads Parquet, CSV, JSON, JSONL, and TSV files directly from the bucket.
What you’ll need
Grant the service account access only to the bucket that Summation should read.
| Field | Required | Stored as | Notes |
|---|
| Base Path | Yes | Config | A gcs:// prefix that scopes the connection, e.g. gcs://my-bucket/path. gs:// paths are also accepted. Browsing starts from this prefix. |
| Service Account Key | Yes | Secret | The full service account JSON key, including the surrounding { and }. |
| HMAC Access ID | Optional | Secret | Cloud Storage HMAC access ID. If set, HMAC Secret must also be set. |
| HMAC Secret | Optional | Secret | Cloud Storage HMAC secret. If set, HMAC Access ID must also be set. |
Grant read access
Grant the service account object viewer access to the bucket you want Summation to read.
PROJECT_ID=my-gcp-project-123
BUCKET_NAME=my-bucket
SERVICE_ACCOUNT=summation@$PROJECT_ID.iam.gserviceaccount.com
gcloud storage buckets add-iam-policy-binding "gs://$BUCKET_NAME" \
--member="serviceAccount:$SERVICE_ACCOUNT" \
--role="roles/storage.objectViewer"
gcloud iam service-accounts keys create summation-gcs-key.json \
--iam-account="$SERVICE_ACCOUNT"
Adding datasets
Each dataset is a single file or folder in the bucket. Supported file formats are parquet, csv, json, jsonl, and tsv. Source references use the form:
gcs://bucket/path/to/data/
Common problems
| Error or symptom | Likely cause |
|---|
GCS base path is required | Base Path is blank or doesn’t include a bucket. |
Invalid GCS service account key | The pasted JSON is incomplete or malformed. Paste the full key file contents. |
GCS authentication failed | The service account key is invalid, disabled, or lacks bucket access. |
GCS bucket does not exist | The bucket name in Base Path is wrong, or the service account cannot see it. |
| HMAC validation error | Only one HMAC field is filled. Provide both HMAC Access ID and HMAC Secret, or leave both blank. |