Destination type
Cloudflare R2 Destination
Use Cloudflare R2 destinations to archive routed events as objects for audit logs, recovery, long-term inspection, or downstream batch processing.
When to use this destination type
Choose CLOUDFLARE_R2 when the receiver target is Client Cloudflare R2 bucket. Destinations are outbound delivery targets: they do not decide whether a source request should be accepted, and they do not own connection filters or transformations. They own where the final delivery goes and how FastHook should authenticate, pace, disable, and inspect that delivery.
A destination can be reused by multiple connections when several source branches should feed the same receiver. Reuse keeps receiver capacity, credentials, and attempt evidence attached to one destination id.
FastHook dashboard fields
In the dashboard, create a destination, set Destination Type to CLOUDFLARE_R2, then fill the fields below.
Account IDClient Cloudflare account ID.
BucketClient R2 bucket to write objects into.
S3 endpointOptional jurisdiction-specific R2 endpoint.
Access Key IDR2 S3 API access key ID.
Secret Access KeyR2 S3 API secret access key.
Session tokenOptional token for temporary credentials.
Object key templateR2 object key template using FastHook tokens such as {{team_id}}, {{source_id}}, {{event_id}}, and payload paths.
Content typeStored object media type, usually application/json or text/plain.
Body templateOptional custom stored body. Leave empty to store the standard metadata and payload JSON envelope.
Include metadataControls standard envelope metadata when body template is empty.
Max delivery rateOptional pacing for archive writes.
API config fields
The REST API stores destination-specific behavior under config. Use PATCH for focused edits and PUT only when your request contains the full config you want to keep.
config.account_idRequired Cloudflare account ID for the client's R2 account.
config.endpointOptional R2 S3 endpoint. Defaults to https://<account_id>.r2.cloudflarestorage.com.
config.bucketRequired client R2 bucket name.
config.key_templateRequired R2 object key template. Defaults to archives/{{team_id}}/{{source_id}}/{{event_id}}.json.
config.content_typeObject content type. Defaults to application/json.
config.body_templateOptional archive body template. When omitted, FastHook stores a JSON envelope with metadata and payload.
config.include_metadataOptional boolean. When body_template is empty, controls whether metadata is included with the stored payload.
config.auth_typeUse R2_ACCESS_KEY.
config.auth.access_key_idRequired R2 Access Key ID.
config.auth.secret_access_keyRequired R2 Secret Access Key.
config.auth.session_tokenOptional session token for temporary R2 credentials.
config.rate_limitOptional delivery pacing for archive writes.
config.rate_limit_periodRate-limit period: second, minute, or hour.
{
"name": "event-r2-archive",
"type": "CLOUDFLARE_R2",
"config": {
"account_id": "d4bb10aba95850d72b7b92dc07783c17",
"endpoint": "https://d4bb10aba95850d72b7b92dc07783c17.r2.cloudflarestorage.com",
"bucket": "client-baket",
"key_template": "archives/{{team_id}}/{{source_id}}/{{event_id}}.json",
"content_type": "application/json",
"body_template": null,
"include_metadata": true,
"auth_type": "R2_ACCESS_KEY",
"auth": {
"access_key_id": "your-r2-access-key-id",
"secret_access_key": "your-r2-secret-access-key"
},
"rate_limit": null,
"rate_limit_period": "second"
}
}curl -X POST "https://api.fasthook.io/v1/destinations" \
-H "Authorization: Bearer $FASTHOOK_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"name": "event-r2-archive",
"type": "CLOUDFLARE_R2",
"config": {
"account_id": "d4bb10aba95850d72b7b92dc07783c17",
"endpoint": "https://d4bb10aba95850d72b7b92dc07783c17.r2.cloudflarestorage.com",
"bucket": "client-baket",
"key_template": "archives/{{team_id}}/{{source_id}}/{{event_id}}.json",
"content_type": "application/json",
"body_template": null,
"include_metadata": true,
"auth_type": "R2_ACCESS_KEY",
"auth": {
"access_key_id": "your-r2-access-key-id",
"secret_access_key": "your-r2-secret-access-key"
},
"rate_limit": null,
"rate_limit_period": "second"
}
}'Authentication
Destination authentication is outbound. It helps the receiver trust or accept FastHook delivery, and it is separate from source authentication that verifies the original webhook producer.
- Cloudflare R2 S3-compatible access key
- Optional temporary session token
HTTP methods and rate limit
This destination type uses the methods below for delivery attempts. Rate limits apply at the destination boundary, so every connection that targets the same destination shares that capacity.
Rate limit: Optional. Configure a max archive write rate per second, minute, or hour.
Delivery behavior
- FastHook signs a PutObject request with AWS Signature Version 4 and writes the routed payload to the configured client R2 bucket.
- Without a body_template, the stored object is a JSON envelope with delivery metadata and the parsed payload when possible.
- With a body_template, FastHook renders the template and stores the rendered body using the configured content type.
- If a connection has no transformation, the archive stores the original routed payload. If a transformation runs first, the archive stores the transformed payload.
- Successful attempts store a requested URL like r2://bucket/archives/... so the object key is visible in delivery evidence.
Setup checklist
- Create or choose a client R2 bucket and an Object Read & Write R2 API token for that bucket.
- Create a FastHook destination and choose CLOUDFLARE_R2 as the destination type.
- Set account ID, bucket, access key ID, and secret access key.
- Set an object key template such as archives/{{team_id}}/{{source_id}}/{{event_id}}.json.
- Keep content type as application/json unless body_template produces another format.
- Leave body template empty to store the standard metadata and payload archive envelope.
- Connect one or more sources to the R2 destination, adding transformations only when you want to archive transformed payloads.
Troubleshooting
Attempts fail with 403 or SignatureDoesNotMatch.Check account_id, endpoint, bucket, access key ID, secret access key, and whether the R2 token has Object Read & Write access to the bucket.
Attempts fail with cloudflare_r2_key_invalid.Check config.key_template. It must render to a relative R2 object key, cannot be empty, and cannot contain .. path segments.
Archived body is not the original inbound request.Check the connection rules. A transformation before the destination changes the payload that R2 stores.
Object content type is wrong.Set config.content_type to match the rendered body, such as application/json for JSON or text/plain for plain text.