Tallinna avaandmed

Tallinn Open Data API

Access

Public FastAPI GET service. No authentication. Dataset pages in the national portal document table names.

Endpoints

• Instructions: https://avaandmed.tallinn.ee/
• OpenAPI: https://avaandmed.tallinn.ee/openapi.json
• Query: https://avaandmed.tallinn.ee/data/
• Known table example: https://avaandmed.tallinn.ee/data/?table=andurid_data&page=1&per_page=2

Retrieve

1. Find the Tallinn dataset in andmed.eesti.ee; read its description for the table name. The API does not list tables — /tables is 404 and /data/ with no table is a 422 Field required. The catalogue's own JSON does this without opening the portal (verified 2026-08-01): GET https://avaandmed.eesti.ee/api/datasets?limit=75&search=<term> (an unknown query parameter is a 400, and limit above 75 is rejected), then GET https://avaandmed.eesti.ee/api/datasets/slug/<slug> for each hit. The table name appears in the detail record either as an avaandmed.tallinn.ee/data/?table=<name> access URL or written into the description as (tabel: <name>). Search the words the dataset uses, not the city: search=tallinn matches 48 datasets and none of the ones this API serves, while search=vanalinna väravate finds andurid_data at once.
2. Query /data/ with required table and optional columns, filters, order_by, page, and per_page.
3. Use page >= 1 and 1 <= per_page <= 1000; paginate until a page is shorter than per_page.
4. Treat filters as the service's documented SQL-WHERE-style expression and URL-encode it.

The andurid_data example returns Old Town gate sensor records with id, andurid_id, name, ts, pir, in, out, humidity, and temp.

Return

Preserve the national catalog page, table name, columns/filter/order, page size, original fields, source endpoint, and retrieval time.

Limits

• A made-up or stale table name returns a JSON 500 with Table not found; the OpenAPI schema alone cannot discover valid tables.

• Maximum documented concurrency is five requests and query timeout is 20 seconds.

• Different tables have unrelated schemas.

• The service reports no row count: a page shorter than per_page is the only end-of-table signal, so a figure is a total only when paging ran to a short page.

Verify

Require HTTP 200 JSON and a list of records. For andurid_data, require andurid_id, name, ts, and numeric count fields. A 422 missing-table response or 500 table-not-found response is not successful access.

Known-good acceptance check, run against the live API by scripts/check-sources.mjs (issue #82):

GET https://avaandmed.tallinn.ee/data/?table=andurid_data&page=1&per_page=2
expect /"andurid_id":\s*\d+/
expect /"ts":\s*"\d{4}-\d{2}-\d{2}/
# The counter is the failure worth pinning: an invented table answers HTTP 500
# with {"detail":"404: Table not found"} rather than an empty list, so a
# mistyped name can never be read as a dataset that holds nothing.
counter GET https://avaandmed.tallinn.ee/data/?table=andurid_data_zzz&page=1&per_page=2

Module API

tallinnOpenData(table, {columns, filters, orderBy, limit, page, perPage}) -> {source, page, table, query, totals, columns, rows, note} tallinnDatasets(term, {limit}) -> {source, page, term, totals, tables, datasets, note}