@lightdash/query-sdk
v0.3258.1
Published
SDK for building custom data apps against the Lightdash semantic layer
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@lightdash/query-sdk
A React SDK for building custom data apps against the Lightdash semantic layer.
Quick start
import {
createClient,
LightdashProvider,
useLightdash,
} from '@lightdash/query-sdk';
const lightdash = createClient();
function App() {
return (
<LightdashProvider client={lightdash}>
<Dashboard />
</LightdashProvider>
);
}
function Dashboard() {
const { data, loading, error } = useLightdash(
lightdash
.model('orders')
.dimensions(['customer_segment'])
.metrics(['total_revenue', 'order_count'])
.filters([
{
field: 'order_date',
operator: 'inThePast',
value: 90,
unit: 'days',
},
])
.sorts([{ field: 'total_revenue', direction: 'desc' }])
.limit(10),
);
if (loading) return <p>Loading...</p>;
if (error) return <p>Error: {error.message}</p>;
return (
<ul>
{data.map((row, i) => (
<li key={i}>
{row.customer_segment}: {row.total_revenue}
</li>
))}
</ul>
);
}Result rows are flat objects with raw typed values (numbers are numbers, strings are strings).
Authentication
The SDK reads credentials from env vars. For Vite projects, add a .env file:
VITE_LIGHTDASH_API_KEY=your-pat-token
VITE_LIGHTDASH_URL=https://app.lightdash.cloud
VITE_LIGHTDASH_PROJECT_UUID=your-project-uuidFor Node/E2B environments, use unprefixed names (LIGHTDASH_API_KEY, etc.).
Calling createClient() with no arguments reads from env vars. You can also pass config explicitly:
const lightdash = createClient({
apiKey: token,
baseUrl: 'https://app.lightdash.cloud',
projectUuid: 'uuid',
});Query builder
Queries are built with a chainable, immutable API. Fields use short names (e.g. driver_name), and the SDK qualifies them automatically for the API.
lightdash
.model('orders')
.dimensions(['customer_name', 'order_date'])
.metrics(['total_revenue', 'order_count'])
.filters([
{ field: 'status', operator: 'equals', value: 'completed' },
{ field: 'amount', operator: 'greaterThan', value: 1000 },
{ field: 'order_date', operator: 'inThePast', value: 90, unit: 'days' },
])
.sorts([{ field: 'total_revenue', direction: 'desc' }])
.limit(100);Supported filter operators: equals, notEquals, greaterThan, lessThan, greaterThanOrEqual, lessThanOrEqual, inThePast, notInThePast, inTheNext, inTheCurrent, notInTheCurrent, inBetween, notInBetween, isNull, notNull, startsWith, endsWith, include, doesNotInclude.
Parameters
Lightdash parameters (${lightdash.parameters.X} substitutions) let a query swap out
pieces of SQL at runtime — for example a comparison-mode dropdown that switches a
year-over-year window between YTD and Last 12 Months.
Parameters must be declared in lightdash.yml / model YAML and referenced via
${lightdash.parameters.X} in SQL. Pass values at query time with .parameters():
function YoYChart() {
const [mode, setMode] = useState('YTD');
const { data } = useLightdash(
lightdash
.model('orders')
.metrics(['revenue_current', 'revenue_previous'])
.parameters({ comparison_mode: mode }),
);
// Changing `mode` produces a new query whose cache key includes the
// parameter value, so results re-fetch and the Current / Previous
// figures update for the selected window.
return (
<select value={mode} onChange={(e) => setMode(e.target.value)}>
<option value="YTD">Year to date</option>
<option value="L12M">Last 12 months</option>
</select>
);
}.parameters() is immutable and merges with prior calls (later keys win). Values can be
strings, numbers, or arrays of either. They are sent at the top level of the API request.
Results
useLightdash(query) returns:
| Field | Type | Description |
| --------- | --------------- | ---------------------------------------------------------------- |
| data | Row[] | Array of flat objects. Numbers are numbers, strings are strings. |
| columns | Column[] | Field metadata for returned rows. |
| format | (row, fieldName) => string | Server-formatted value for a field. |
| totalResults | number \| null | Total rows returned by the loaded source query. |
| loading | boolean | True while the query is running. |
| error | Error \| null | Error if the query failed. |
| refetch | () => void | Re-run the query. |
| queryUuid | string \| null | Async query UUID for the loaded source query. |
| getUnderlyingData | ({ row, metric, limit? }) => Promise<UnderlyingDataResult> | Fetch raw rows behind an aggregated metric value. |
| downloadUnderlyingData | ({ row, metric, fileType?, values?, limit?, filename? }) => Promise<DownloadResultsResult> | Schedule a backend CSV/XLSX export for raw rows behind an aggregated metric value. |
| downloadResults | ({ fileType?, values?, limit?, filename? }) => Promise<DownloadResultsResult> | Schedule a backend CSV/XLSX export for this query. |
Underlying data
Use getUnderlyingData() to retrieve the raw rows behind a metric value from an
already-loaded query result:
function RevenueTable() {
const { data, getUnderlyingData } = useLightdash(
lightdash
.model('orders')
.dimensions(['customer_segment'])
.metrics(['total_revenue']),
);
async function openUnderlying(row) {
const result = await getUnderlyingData({
row,
metric: 'total_revenue',
limit: 500,
});
console.log(result.rows);
}
return data.map((row) => (
<button onClick={() => openUnderlying(row)}>
View {row.customer_segment}
</button>
));
}Call it from a user action. Pass the original row from data and the same
metric name used in .metrics([...]).
Use downloadUnderlyingData() when the user wants to export those underlying
rows without fetching or serializing them in the iframe:
function RevenueTable() {
const { data, downloadUnderlyingData } = useLightdash(
lightdash
.model('orders')
.dimensions(['customer_segment'])
.metrics(['total_revenue']),
);
return data.map((row) => (
<button
onClick={() =>
downloadUnderlyingData({
row,
metric: 'total_revenue',
fileType: 'csv',
values: 'formatted',
limit: 'all',
filename: `orders-${row.customer_segment}`,
})
}
>
Download rows
</button>
));
}For underlying-data downloads, limit: 'table' uses the backend's default
underlying-data row limit, limit: 'all' asks Lightdash for all matching rows
within backend export caps, and a number requests that many rows.
Backend downloads
Use downloadResults() to export query results through Lightdash's backend
CSV/XLSX pipeline:
function ResultsTable() {
const { data, columns, format, downloadResults } = useLightdash(
lightdash
.model('orders')
.dimensions(['customer_segment'])
.metrics(['total_revenue']),
);
return (
<button
onClick={() =>
downloadResults({
fileType: 'xlsx',
values: 'formatted',
limit: 'table',
filename: 'revenue-by-segment',
})
}
>
Download
</button>
);
}Options:
fileType:'csv'or'xlsx'; defaults to'csv'.values:'formatted'or'raw'; defaults to'formatted'.limit:'table','all', or a custom positive row count; defaults to'table'.filename: optional download filename without extension.
limit: 'table' reuses the loaded query. limit: 'all' and custom limits
rerun the same metric query with the requested row limit, wait for it to be
ready, and then schedule the backend export job. The full export is generated
by Lightdash; rows are not serialized in the app iframe.
User context
const user = await lightdash.auth.getUser();
// { name: 'John Doe', email: '...', role: 'admin', orgId: '...', attributes: {} }How it works
createClient()sets up auth and the API transport<LightdashProvider>makes the transport available to hooks via React contextuseLightdash(query)posts to the async metric query endpoint, polls for results, and returns flat rows- Field IDs are auto-qualified (
driver_namebecomesfct_race_results_driver_namefor the API)
Development
pnpm -F query-sdk typecheck # type check
pnpm -F query-sdk lint # lint
pnpm -F query-sdk fix-format # format with oxfmtSee example/ for a working F1 dashboard demo.
