tap-snowflake

tap-snowflake is a Singer tap for Snowflake.

Built with the Meltano Tap SDK for Singer Taps.

Installation

pipx install git+https://github.com/MeltanoLabs/tap-snowflake.git

Configuration

Accepted Config Options

A full list of supported settings and capabilities for this tap is available by running:

tap-snowflake --about

tables configuration parameter.

An array of the table names that you want to sync. The table names should be fully qualified, including schema and table name.

NOTES:

• This limits discovery to the tables specified for performance reasons. Do not specify tables if you intend to discover the entire available catalog.
• Syntax to specify tables differs slightly from select (schema_name.table_name vs schema_name-table_name.*)

:bulb: When adding more elements to select ensure the table is specified in tables if using tables.

Example:

  ...
  tables:
    - schema_name1.table1
    - schema_name1.table2

Configure using environment variables

This Singer tap will automatically import any environment variables within the working directory's .env if the --config=ENV is provided, such that config values will be considered if a matching environment variable is set either in the terminal context or in the .env file.

Source Authentication and Authorization

This tap supports two authentication methods:

• Standard username and password auth
• Key Pair Authentication

Key Pair Authentication

Key Pair authentication can be enabled by specifing either the private_key of the private_key_path, and optionally the private_key_passphrase if required.

Enabling Batch Messaging

This tap is built using the Meltano SDK and therefore supports a BATCH message type, in addition to the RECORD messages of the Singer spec. This can be enabled either by adding the following to your config.json:

{
  // ...
  "batch_config": {
    "encoding": {
      "format": "jsonl",
      "compression": "gzip"
    },
    "storage": {
      "root": "file://tests/core/resources",
      "prefix": "test-batch"
    }
  }
}

or its equivalent to your meltano.yml

config:
  plugins:
    extractors:
      - name: tap-snowflake
        config:
          batch_config:
            encoding:
              format: jsonl
              compression: gzip
            storage:
              root: "file://tests/core/resources"
              prefix: test-batch

Note: This variant of tap-snowflake does not yet support the INCREMENTAL replication strategy in BATCH mode. Follow here for updates.

arrow encoding

In addition to jsonl, encoding.format also accepts arrow:

{
  "batch_config": {
    "encoding": {
      "format": "arrow"
    },
    "storage": {
      "root": "file:///tmp/tap-snowflake-batches"
    },
    "batch_size": 500000
  }
}

Unlike jsonl, which unloads rows to the Snowflake-managed internal user stage via COPY INTO and then downloads them (LIST/GET), arrow reads query results directly using snowflake-connector-python's native Arrow result format (Snowflake's wire format is already Arrow) -- no stage, intermediate JSON encoding, or extra download round trip. batch_size controls how many rows accumulate before a new Arrow IPC file is flushed (default 10000, matching the SDK's default). As with jsonl, batch files are written to local storage only and are not cleaned up by the tap -- the consumer owns their lifecycle.

Usage

You can easily run tap-snowflake by itself or in a pipeline using Meltano.

Executing the Tap Directly

tap-snowflake --version
tap-snowflake --help
tap-snowflake --config CONFIG --discover > ./catalog.json

Developer Resources

Initialize your Development Environment

curl -LsSf https://astral.sh/uv/install.sh | sh # https://docs.astral.sh/uv/getting-started/installation/
uv sync

Create and Run Tests

Create tests within the tap_snowflake/tests subfolder and then run:

uv run pytest

You can also test the tap-snowflake CLI interface directly using uv run:

uv run tap-snowflake --help

Testing with Meltano

Note: This tap will work in any Singer environment and does not require Meltano. Examples here are for convenience and to streamline end-to-end orchestration scenarios.

Your project comes with a custom meltano.yml project file already created. Open the meltano.yml and follow any "TODO" items listed in the file.

Next, install Meltano (if you haven't already) and any needed plugins:

# Install meltano
pipx install meltano
# Initialize meltano within this directory
cd tap-snowflake
meltano install

Now you can test and orchestrate using Meltano:

# Test invocation:
meltano invoke tap-snowflake --version
# OR run a test `elt` pipeline:
meltano elt tap-snowflake target-jsonl

SDK Dev Guide

See the dev guide for more instructions on how to use the SDK to develop your own taps and targets.