diff --git a/docs/website/docs/dlt-ecosystem/destinations/clickhouse.md b/docs/website/docs/dlt-ecosystem/destinations/clickhouse.md index 58551751c5..bc9cee899b 100644 --- a/docs/website/docs/dlt-ecosystem/destinations/clickhouse.md +++ b/docs/website/docs/dlt-ecosystem/destinations/clickhouse.md @@ -115,12 +115,14 @@ destination. The `clickhouse` destination has a few specific deviations from the default sql destinations: -1. `Clickhouse` has an experimental `object` datatype, but we have found it to be a bit unpredictable, so the dlt clickhouse destination will load the complex datatype to a `text` column. If you need this feature, get in touch with our Slack community, and we will consider adding it. +1. `Clickhouse` has an experimental `object` datatype, but we have found it to be a bit unpredictable, so the dlt clickhouse destination will load the complex datatype to a `text` column. If you need + this feature, get in touch with our Slack community, and we will consider adding it. 2. `Clickhouse` does not support the `time` datatype. Time will be loaded to a `text` column. 3. `Clickhouse` does not support the `binary` datatype. Binary will be loaded to a `text` column. When loading from `jsonl`, this will be a base64 string, when loading from parquet this will be the `binary` object converted to `text`. 4. `Clickhouse` accepts adding columns to a populated table that are not null. -5. `Clickhouse` can produce rounding errors under certain conditions when using the float / double datatype. Make sure to use decimal if you cannot afford to have rounding errors. Loading the value 12.7001 to a double column with the loader file format jsonl set will predictbly produce a rounding error for example. +5. `Clickhouse` can produce rounding errors under certain conditions when using the float / double datatype. Make sure to use decimal if you cannot afford to have rounding errors. Loading the value + 12.7001 to a double column with the loader file format jsonl set will predictbly produce a rounding error for example. ## Supported column hints @@ -173,51 +175,42 @@ pipeline = dlt.pipeline( ) ``` -### Using Google Cloud Storage as a Staging Area +### Using S3-Compatible Storage as a Staging Area -dlt supports using Google Cloud Storage (GCS) as a staging area when loading data into ClickHouse. This is handled automatically by -ClickHouse's [GCS table function](https://clickhouse.com/docs/en/sql-reference/table-functions/gcs) which dlt uses under the hood. +dlt supports using S3-compatible storage services, including Google Cloud Storage (GCS), as a staging area when loading data into ClickHouse. +This is handled automatically by +ClickHouse's [GCS table function](https://clickhouse.com/docs/en/sql-reference/table-functions/gcs), which dlt uses under the hood. -The clickhouse GCS table function only supports authentication using Hash-based Message Authentication Code (HMAC) keys. To enable this, GCS provides an S3 compatibility mode that emulates -the Amazon S3 -API. ClickHouse takes advantage of this to allow accessing GCS buckets via its S3 integration. +The ClickHouse GCS table function only supports authentication using Hash-based Message Authentication Code (HMAC) keys, which is compatible with the Amazon S3 API. +To enable this, GCS provides an S3 +compatibility mode that emulates the S3 API, allowing ClickHouse to access GCS buckets via its S3 integration. + +For detailed instructions on setting up S3-compatible storage with dlt, including AWS S3, MinIO, and Cloudflare R2, refer to +the [dlt documentation on filesystem destinations](https://dlthub.com/docs/dlt-ecosystem/destinations/filesystem#using-s3-compatible-storage). To set up GCS staging with HMAC authentication in dlt: 1. Create HMAC keys for your GCS service account by following the [Google Cloud guide](https://cloud.google.com/storage/docs/authentication/managing-hmackeys#create). -2. Configure the HMAC keys as well as the `client_email`, `project_id` and `private_key` for your service account in your dlt project's ClickHouse destination settings in `config.toml`: +2. Configure the HMAC keys (`aws_access_key_id` and `aws_secret_access_key`) in your dlt project's ClickHouse destination settings in `config.toml`, similar to how you would configure AWS S3 + credentials: ```toml [destination.filesystem] -bucket_url = "gs://dlt-ci" +bucket_url = "s3://my_awesome_bucket" [destination.filesystem.credentials] -project_id = "a-cool-project" -client_email = "my-service-account@a-cool-project.iam.gserviceaccount.com" -private_key = "-----BEGIN PRIVATE KEY-----\nMIIEvQIBADANBgkaslkdjflasjnkdcopauihj...wEiEx7y+mx\nNffxQBqVVej2n/D93xY99pM=\n-----END PRIVATE KEY-----\n" - -[destination.clickhouse.credentials] -database = "dlt" -username = "dlt" -password = "Dlt*12345789234567" -host = "localhost" -port = 9440 -secure = 1 -gcp_access_key_id = "JFJ$$*f2058024835jFffsadf" -gcp_secret_access_key = "DFJdwslf2hf57)%$02jaflsedjfasoi" +aws_access_key_id = "JFJ$$*f2058024835jFffsadf" +aws_secret_access_key = "DFJdwslf2hf57)%$02jaflsedjfasoi" +project_id = "my-awesome-project" +endpoint_url = "https://storage.googleapis.com" ``` -Note: In addition to the HMAC keys (`gcp_access_key_id` and `gcp_secret_access_key`), you now need to provide the `client_email`, `project_id` and `private_key` for your service account -under `[destination.filesystem.credentials]`. -This is because the GCS staging support is now implemented as a temporary workaround and is still unoptimized. - -dlt will pass these credentials to ClickHouse which will handle the authentication and GCS access. - -There is active work in progress to simplify and improve the GCS staging setup for the ClickHouse dlt destination in the future. Proper GCS staging support is being tracked in these GitHub issues: - -- [Make filesystem destination work with gcs in s3 compatibility mode](https://github.com/dlt-hub/dlt/issues/1272) -- [GCS staging area support](https://github.com/dlt-hub/dlt/issues/1181) +:::caution +When configuring the `bucket_url` for S3-compatible storage services like Google Cloud Storage (GCS) with ClickHouse in dlt, ensure that the URL is prepended with `s3://` instead of `gs://`. This is +because the ClickHouse GCS table function requires the use of HMAC credentials, which are compatible with the S3 API. Prepending with `s3://` allows the HMAC credentials to integrate properly with +dlt's staging mechanisms for ClickHouse. +::: ### dbt support diff --git a/tests/load/clickhouse/test_clickhouse_gcs_s3_compatibility.py b/tests/load/clickhouse/test_clickhouse_gcs_s3_compatibility.py index 8bc5c59c14..481cd420c6 100644 --- a/tests/load/clickhouse/test_clickhouse_gcs_s3_compatibility.py +++ b/tests/load/clickhouse/test_clickhouse_gcs_s3_compatibility.py @@ -14,10 +14,15 @@ def test_clickhouse_gcs_s3_compatibility() -> None: def dummy_data() -> Generator[Dict[str, int], None, None]: yield {"field1": 1, "field2": 2} + gcp_bucket = filesystem( + GCS_BUCKET.replace("gs://", "s3://"), destination_name="filesystem_s3_gcs_comp" + ) - gcp_bucket = filesystem(GCS_BUCKET.replace("gs://", "s3://"), destination_name="filesystem_s3_gcs_comp") - - pipe = dlt.pipeline(pipeline_name="gcs_s3_compatibility", destination="clickhouse", staging=gcp_bucket, - full_refresh=True, ) + pipe = dlt.pipeline( + pipeline_name="gcs_s3_compatibility", + destination="clickhouse", + staging=gcp_bucket, + full_refresh=True, + ) pack = pipe.run([dummy_data]) assert_load_info(pack)