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What it does

YTsaurus ships with CHYT — a ClickHouse-over-YT engine — but its HTTP interface isn't perfectly compatible with JDBC drivers.
ytsaurus-clickhouse-proxy sits in front of CHYT and:

• Intercepts system.tables, system.columns, system.databases queries and returns a virtual catalog you define in a single Python file
• Rewrites friendly table aliases (analytics.orders) into real YT paths (//home/my_project/prod/orders) transparently
• Handles both single tables and date-partitioned directories (concatYtTablesRange)
• Strips incompatible query parameters (e.g. compress=1) before forwarding
• Works out of the box with DBeaver, DataGrip, and any other JDBC ClickHouse client

DBeaver / DataGrip
       │  JDBC (ClickHouse driver)
       ▼
ytsaurus-clickhouse-proxy  :8123
       │  Rewrites queries · Injects virtual catalog
       ▼
YTsaurus CHYT clique
       │
       ▼
   YT Tables

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Installation

pip install ytsaurus-clickhouse-proxy

Or from source:

git clone https://github.com/klipbn/ytsaurus_clickhouse_proxy.git
cd ytsaurus-clickhouse-proxy
pip install -e .

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Quick Start

1. Configure your table catalog

Edit yt_clickhouse_proxy/logical_catalog.py and describe which YT tables you want to see in your IDE:

LOGICAL_CATALOG = {
    # Schema name visible in DBeaver
    "analytics": {
        # Alias → single YT table
        "orders": {
            "type": "table",
            "path": "//home/my_project/prod/orders",
        },
        # Alias → date-partitioned directory
        "events_1d": {
            "type": "range",
            "base": "//home/my_project/logs/events/1d",
            "sample": "2024-01-01",   # used for schema introspection
        },
    },
}

2. Set environment variables

export YT_PROXY=http://your-yt-cluster.example.com
export YT_TOKEN_PATH=~/.yt/token       # file containing your OAuth token
export CLIQUE_ALIAS=ch_public          # CHYT clique name

3. Run

ytsaurus-clickhouse-proxy
# or
python -m yt_clickhouse_proxy
# or with uvicorn directly
uvicorn yt_clickhouse_proxy:app --host 0.0.0.0 --port 8123

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Connect from DBeaver

Field	Value
Driver	ClickHouse
JDBC URL	jdbc:clickhouse://127.0.0.1:8123/analytics
Username	your CHYT clique alias (e.g. ch_public)
Password	your YT OAuth token
Driver property compress	false
Driver property check_table_existence	false

Once connected, you'll see your logical schemas and tables in the navigator:

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Environment Variables

Variable	Default	Description
YT_PROXY	(required)	YTsaurus cluster HTTP address
YT_TOKEN_PATH	~/.yt/token	Path to file containing your OAuth token
CLIQUE_ALIAS	ch_public	CHYT clique alias
DEFAULT_FORMAT	RowBinaryWithNamesAndTypes	ClickHouse wire format
MAX_TABLES_IN_COLUMNS_UNION	100	Max tables fetched in a single system.columns request

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Docker

Build and run

docker build -t ytsaurus-clickhouse-proxy .

docker run -d \
  --name ytsaurus-clickhouse-proxy \
  -p 8123:8123 \
  -v ~/.yt/token:/root/.yt/token:ro \
  -e YT_PROXY=http://your-yt-cluster.example.com \
  -e CLIQUE_ALIAS=ch_public \
  ytsaurus-clickhouse-proxy

With Docker Compose

# edit YT_PROXY in docker-compose.yml first
docker compose up -d
docker compose logs -f

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Example SQL Queries

-- List all tables in your catalog
SELECT name, engine, database
FROM system.tables
WHERE database = 'analytics';

-- Inspect column types (JDBC metadata)
SELECT TABLE_NAME, COLUMN_NAME, TYPE_NAME, DATA_TYPE, ORDINAL_POSITION
FROM system.columns
WHERE TABLE_NAME = 'orders'
ORDER BY ORDINAL_POSITION;

-- Query data via alias
SELECT date, count() AS cnt
FROM analytics.events_1d
WHERE date >= '2024-01-01'
GROUP BY date
ORDER BY date;

-- Or pass a raw YT path directly (CHYT native syntax)
SELECT *
FROM concatYtTablesRange('//home/my_project/logs/events/1d', '2024-01-01', '2024-01-31')
LIMIT 100;

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Logical Catalog Reference

LOGICAL_CATALOG = {
    "<schema_name>": {
        "<table_alias>": {
            # ── Option A: single table ──────────────────────────────────
            "type": "table",
            "path": "//home/my_project/some_table",

            # ── Option B: date-partitioned directory ────────────────────
            "type": "range",
            "base": "//home/my_project/logs/events/1d",
            "sample": "2024-01-01",   # one valid partition for DESCRIBE
        },
    },
}

• type: "table" — proxied as SELECT … FROM `//path`
• type: "range" — proxied as SELECT … FROM concatYtTablesRange('base', …) with the full date range passed by the caller

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Known Limitations

• system.columns without a table filter returns a limited result set to avoid hitting CHYT's max_query_size limit
• No authentication layer — the proxy inherits your YT token; do not expose port 8123 publicly without a firewall
• compress=1 from JDBC is silently dropped (CHYT handles its own transport compression)

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Contributing

Pull requests are welcome! Please open an issue first to discuss what you'd like to change.

git clone https://github.com/klipbn/ytsaurus_clickhouse_proxy.git
cd ytsaurus-clickhouse-proxy
pip install -e ".[dev]"

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License

MIT © 2026 Alexey Voronko