How to create a named demo¶
A named demo is a self-contained, reusable demo environment you drop into demo/named/<name>/.
Once the directory exists, start-ui-install.sh --demo <name> picks it up with no change to
the launcher script and no developer involvement required (REQ-1858). This is the mechanism for
client-specific and vertical demo scenarios — a future --demo banking or --demo healthcare
is just a new directory in this shape.
Named demos are distinct from the --source=<name> mechanism. The --source flag adds a single
toy source to the standard demo (backed by demo/sources/<name>/). A named demo is a
self-contained multi-source package: its own config.yaml (a whole config), its own
docker-compose.yml when it has data stores, and whatever seeding tooling the scenario needs.
The fixed directory layout¶
Every named demo lives at demo/named/<name>/ and contains these files:
demo/named/<name>/
demo.yaml # required for published demos — bundle metadata and page card
config.yaml # required — the demo's whole config, used in place of the standard demo's
docker-compose.yml # the demo's own data stores at build and authoring time (omit if none)
docker-compose.run.yml # the run-time stores, loaded from the bundle's dumps (omit if none)
setup.yaml # optional — commands and MV refreshes to run once after the server is up
tour.yaml # the demo tour, one step per object it shows
queries/ # named example queries the tour or Polly can reference
Dockerfile.seeder # if the demo self-seeds (recommended)
seed.py # entrypoint for the seeder service
generate_*.py # one per data store, optional but conventional
logs/ # optional — log files the containers write, for the demo's Logs sources
start-ui-install.sh picks the demo's config generically, from demo/named/$DEMO_NAME/
[tool-verified]:
# start-ui-install.sh, after the directory check
_NAMED_WHOLE=false
if [ -n "$DEMO_NAME" ]; then
_NC="$SCRIPT_DIR/demo/named/$DEMO_NAME/config.yaml"
_NF="$SCRIPT_DIR/demo/named/$DEMO_NAME/fragment.yaml"
if [ -f "$_NC" ] && [ -f "$_NF" ]; then
echo "--demo $DEMO_NAME has both config.yaml and fragment.yaml in demo/named/$DEMO_NAME/. Keep one: ..."; exit 1
fi
if [ ! -f "$_NC" ] && [ ! -f "$_NF" ]; then
echo "--demo $DEMO_NAME has no config.yaml (and no fragment.yaml) in demo/named/$DEMO_NAME/ to register it with."; exit 1
fi
[ -f "$_NC" ] && _NAMED_WHOLE=true
fi
config.yaml is a whole config: the launcher sets PROVISA_CONFIG to it in place of the
standard demo config (config/provisa-install.yaml), so the demo is exactly what the file lists.
A --source toy source is still overlaid on top. A demo may instead ship a fragment.yaml,
overlaid on the standard config; a demo with neither, or with both, is refused by name. The name
itself is not in any registry or allowlist.
The one-start-point invariant¶
docker compose up -d against docker-compose.yml is the complete setup-and-seed story. No
manual commands. No host-side scripts to run before it works.
This does not mean the demo must be a single process or single container. The perf demo
runs five containers (four engines plus a seeder) [tool-verified]. A demo may also reference
external managed resources it does not containerize — a live Databricks or Snowflake source
reached by connection string, registered in config.yaml with no corresponding compose
service. Those are implementation details behind the single entry point.
What the invariant prohibits: telling the solutions engineer to run scripts by hand, set up databases manually, or issue commands in a specific order. One command, fully automated.
The seeder pattern¶
Heavy data generation must not re-run on every container restart. The perf demo uses a
seeder service that writes a marker file on a bind-mounted directory [tool-verified]:
# demo/named/perf/seed.py:29,42-43
MARKER = Path("/data-marker/.seeded")
def main() -> int:
if MARKER.exists():
print(f"perf demo already seeded ({MARKER.read_text().strip()}); skipping")
return 0
When the seeder container starts, it checks for the marker. If present, it exits immediately. If
absent, it runs all generation scripts in sequence, then writes the marker. Because the marker
lives on the bind-mounted data/ directory, it survives container restarts but not data/
being deleted. A start without --keep-data deletes it, so the marker only matters to a demo started
with --keep-data. [tool-verified]
The seeder service in docker-compose.yml gates on every other service's healthcheck
[tool-verified]:
# demo/named/perf/docker-compose.yml:129-137
depends_on:
postgresql:
condition: service_healthy
mongodb:
condition: service_healthy
clickhouse:
condition: service_healthy
neo4j:
condition: service_healthy
For lighter demos — a few hundred rows, fast to regenerate — skipping the marker and letting the seeder re-run every start is fine. The marker pattern is only necessary when generation takes minutes or writes gigabytes.
Volumes: named for databases, the demo directory for files¶
A database's storage is a named volume of the compose project (weblogs_pg, sonnets_pg,
sonnets_qdrant). docker compose down -v removes it, so a test that runs the demo's compose
file under its own project starts from an empty database every run and leaves nothing in the
checkout [tool-verified: demo/named/weblogs/docker-compose.yml,
demo/named/sonnets/docker-compose.yml, tests/integration/test_sonnets_demo.py].
What the demo's own tooling reads or writes as files -- the seeder's marker, log files a Logs
source reads -- goes under ${PROVISA_NAMED_DEMO_DIR:-.}: the demo's directory when
start-ui-install.sh runs it, a temporary directory when a test sets the variable
[tool-verified: demo/named/weblogs/docker-compose.yml]:
# demo/named/weblogs/docker-compose.yml (excerpt)
volumes:
- weblogs_pg:/var/lib/postgresql/data
- ${PROVISA_NAMED_DEMO_DIR:-.}/logs/postgres:/var/log/pglog
...
seeder:
volumes:
- ${PROVISA_NAMED_DEMO_DIR:-.}/data:/data-marker
demo/named/*/data/ is ignored by git. The perf demo predates this and binds its stores to
./data/.
Container labels¶
Every service in docker-compose.yml carries two labels [tool-verified]:
# demo/named/perf/docker-compose.yml:36-37, 43-44
x-demo-labels: &demo-labels
com.provisa.demo: perf # replace with your demo name
services:
postgresql:
labels:
<<: *demo-labels
com.provisa.demo.role: rdb # role: rdb / dw / doc-store / graph / seeder / etc.
com.provisa.demo groups every container the demo starts so
docker ps --filter label=com.provisa.demo=<name> lists exactly those containers without
needing the compose file open. com.provisa.demo.role identifies each service's part.
The role value determines what the bundle build does with each store: [tool-verified: scripts/demo_bundle.py Stores.dump]
rdb— a Postgres service: dumped todump/<service>.sqlat build.vector— a Qdrant service: each collection saved asdump/<service>/<collection>.snapshotat build.document— a MongoDB service: every database dumped as one gzipped archive,dump/<service>.archive.gz, read as the administrator itsMONGO_INITDB_ROOT_USERNAMEandMONGO_INITDB_ROOT_PASSWORDname.search— an Elasticsearch service: its indices snapshotted to the repository itspath.reponames, copied out todump/<service>/.graph— a Neo4j service: stopped, and itsneo4jdatabase dumped todump/<service>/neo4j.dump. It is dumped after every other store.seeder— run once during the build (and during development starts); never in a bundle.
config.yaml — the demo's whole config¶
config.yaml is a static, checked-in config file in Provisa's standard YAML config format. Every
start rebuilds the control plane from it. The usual way to produce it is to run the standard demo,
build the scenario in the UI, and export the model (Admin → Maintenance → Configuration File →
View / Diff, the Current pane, or GET /admin/config/live), then save it as config.yaml.
The export omits sources added in the UI, so add them to sources: by hand. The excerpts below
come from demo/named/perf/config.yaml, which is the standard demo config with the perf sections
appended.
Every source needs explicit tables:¶
Register each source and then list every table it exposes. A bare sources: entry never
produces tables in the SQL catalog, for any connector type, because the catalog is built from the
registered tables [tool-verified from the notes in demo/named/perf/config.yaml]:
# demo/named/perf/config.yaml, the bench-postgresql source
- id: bench-postgresql
type: postgresql
host: ${env:PROVISA_BENCH_POSTGRESQL_HOST:-localhost}
port: ${env:PROVISA_BENCH_POSTGRESQL_PORT:-25632}
database: provisa_bench
username: provisa
password: provisa
Use env-var interpolation with a :- default for every host and port. The seeder uses the
in-container service name as the host; the host-side generate scripts use localhost plus the
published port. The config uses the same env-var names so both work without editing the file
[tool-verified from generate_postgres.py:29-30]:
HOST = os.environ.get("PROVISA_BENCH_POSTGRESQL_HOST", "localhost")
PORT = int(os.environ.get("PROVISA_BENCH_POSTGRESQL_PORT", "25632"))
Sources backed by api_source (each table is a query)¶
Neo4j is an api_source-backed type where each table is one fixed Cypher projection. You
hand-author every table in config.yaml:
# demo/named/perf/config.yaml (excerpt)
tables:
- source_id: bench-neo4j
domain_id: perf-bench
schema: neo4j
table: bench_order_node
description: One row per Order node
query_template: >-
MATCH (o:Order)
RETURN o.order_id AS order_id, o.customer_id AS customer_id, ...
ORDER BY o.order_id
columns:
- {name: order_id, data_type: integer, is_primary_key: true, visible_to: [org_admin, analyst]}
- {name: customer_id, data_type: integer, visible_to: [org_admin, analyst]}
...
query_template is a Cypher query whose result set becomes the table. Write it from the actual
schema your generation scripts produce, not from an assumed schema. Each column entry matches
Provisa's Column model shape: name, data_type, optional is_primary_key, and
visible_to (list of role names).
Relationships¶
Cross-table relationships go in a top-level relationships: block [tool-verified]:
# demo/named/perf/config.yaml (excerpt)
relationships:
- id: bench-placed-to-customer
source_table_id: bench_placed_edge
source_column: customer_id
target_table_id: bench_customer_node
target_column: customer_id
cardinality: many-to-one
Relationship IDs must be unique within the file. Table IDs referenced here come from the
table: field in the tables: block above, or from auto-discovered tables for native
connectors (use the actual table name as the ID for those).
demo.yaml — bundle metadata and page card¶
demo.yaml is required for any demo that will be published as a bundle. It holds three kinds of
fields [tool-verified: demo/named/weblogs/demo.yaml, demo/named/sonnets/demo.yaml]:
# demo/named/weblogs/demo.yaml
title: Web shop logs
description: >-
A web shop's nginx access log and its database's statement log, read as tables and joined to
the shop's own data...
screenshot: card.png
published: true
requires_provisa: 0.1.0a483
| Field | Required | Meaning |
|---|---|---|
published |
yes | true publishes this demo as a bundle; false skips it in the workflow |
requires_provisa |
yes | The oldest Provisa release the bundle runs on; the build refuses a missing value |
title |
for published | The demo's name on the live demos page |
description |
for published | The card text on the live demos page |
screenshot |
for published | card.png, a PNG in the same directory |
extras |
optional | Python extras to install before the bundle build (e.g. [vector] for sentence-transformers) |
The extras field installs additional Provisa optional dependencies before the demo's setup
runs. The sonnets demo uses [vector] to install the sentence-transformers package needed to
embed its lines. [tool-verified: demo/named/sonnets/demo.yaml]
setup.yaml — run once, on first start and at bundle build¶
setup.yaml names what the demo needs run after the server is up. The launcher runs it on a
demo's first start (a new control plane). The bundle build runs it before dumping the stores, so
the setup's effects are in the dumps from the start. [tool-verified: start-ui-install.sh:875-878,
scripts/demo_bundle.py:417-418]
The file is a list of steps, each one command or refresh [tool-verified: scripts/run_demo_setup.py]:
# demo/named/sonnets/setup.yaml
steps:
- command: embed_lines # calls the embed_lines command as org_admin
- command: link_echoes # calls the link_echoes command as org_admin
- refresh: theme_time # builds the stored rows of the view_theme_time materialized view
- refresh: theme_beauty
- refresh: theme_mortality
- refresh: theme_jealousy
- refresh: theme_verse
A command: step calls a GraphQL mutation of that name (as org_admin, no arguments). A
refresh: step calls refreshMv on the named view. The first step that fails stops the run
and names the step. Nothing is retried.
The launcher marks a demo set up by adding its name to the operator setting
demo.setup_completed. A demo already listed there is not set up again against the same control
plane. [tool-verified: scripts/run_demo_setup.py, SETTING = "demo.setup_completed"]
A bundled demo's setup does not run again where it runs. What setup wrote is already in the bundle's dumps.
docker-compose.run.yml — the run-time stores¶
A bundle does not run docker-compose.yml (the authoring compose, with the seeder). It runs
docker-compose.run.yml, which brings up only what reading the bundle needs: the stores loaded
from the build's dumps. [tool-verified: start-ui-install.sh:359-365, comments in
demo/named/weblogs/docker-compose.run.yml]
Every service in docker-compose.run.yml carries the standard labels plus three that the
node's sync script reads to build stores.env [tool-verified: demo/named/weblogs/docker-compose.run.yml,
demo/named/sonnets/docker-compose.run.yml]:
# demo/named/weblogs/docker-compose.run.yml (excerpt)
services:
postgres:
labels:
com.provisa.demo: weblogs
com.provisa.demo.role: rdb
com.provisa.demo.host_env: WEBLOGS_PG_HOST # the env var config.yaml reads for the host
com.provisa.demo.port_env: WEBLOGS_PG_PORT # the env var config.yaml reads for the port
com.provisa.demo.port: "5432" # the container port (not the published port)
ports:
# On the loopback only. ${VAR-default}: unset → default port; set empty → Docker picks one.
- "127.0.0.1:${WEBLOGS_PG_PORT-28432}:5432"
volumes:
- weblogs_run_pg:/var/lib/postgresql/data
- ./dump/postgres.sql:/docker-entrypoint-initdb.d/10-shop.sql:ro
Four things to get right:
- Ports on the loopback. Every port binding is
127.0.0.1:<var>:<container port>. The node runs several versions of the same demo at once; each gets its own port, picked by Docker when${VAR}is set empty. ${VAR-default}syntax. The single dash (-, not:-) means "use the default when unset or empty". The node sets the variable empty to let Docker pick a port; the default applies for a developer's local start.- The three
host_env/port_env/portlabels. The node'sscripts/demo_stores_sync.shreads them to buildstores.env, the file that tells the tier where each store is. Without them, the node cannot connect the running store to the config's env-var references. - Read-only roles. Give each store a reader credential and use it in
config.yaml. The store is shared by every sandbox of its version, so Provisa should never write to it. The sonnets demo's Qdrant store grants Provisa only its read-only key [tool-verified:demo/named/sonnets/docker-compose.run.yml:QDRANT__SERVICE__READ_ONLY_API_KEY].
The reviews demo's run-time compose file loads its three stores the first time each starts
[tool-verified: demo/named/reviews/docker-compose.run.yml, demo/named/reviews/db/]:
- MongoDB restores the archive from an init script (
db/mongo-restore.shin/docker-entrypoint-initdb.d/); Provisa reads asreviews_reader, whose role reads every database and writes none. - Elasticsearch starts through
db/es-restore.sh, which registers the snapshot repository read only at/snapshots, restores it, and blocks writes to every index. - Neo4j starts through
db/neo4j-load.sh, which loads the dump when the data volume holds no database yet;NEO4J_dbms_databases_default__to__read__onlymakes every database read only.
A Qdrant store's run-time compose file recovers its collections from the build's snapshots at
start [tool-verified: demo/named/sonnets/docker-compose.run.yml]:
# demo/named/sonnets/docker-compose.run.yml (excerpt)
qdrant:
image: qdrant/qdrant:v1.19.1
command: ["./qdrant", "--snapshot", "/snapshots/sonnet_lines.snapshot:sonnet_lines"]
volumes:
- sonnets_run_qdrant:/qdrant/storage
- ./dump/qdrant:/snapshots:ro
Data rule — what the bundle serves live vs. from the dump¶
A demo reads its own sources live wherever it runs: the Postgres database loaded from the
dump, the Qdrant store recovered from the snapshot, the log files shipped in the bundle, the
file sources in the bundle's directory. These are the sources in its docker-compose.run.yml,
or files bundled with it. [tool-verified: scripts/demo_bundle.py:381-394, _replicates()]
Only external SaaS-account sources — a Snowflake table, a Databricks dataset, anything the demo cannot ship in a container — are served from replicas: landed once at bundle build time (when the stores run and the data is current) and read from those replicas in the bundle.
The build detects which tables need replicas and writes the seed only when there are any. A demo of only local or file sources has no seed to write and no replica to serve.
tour.yaml — the demo's guided tour¶
Every published demo has a tour.yaml. It describes the demo step by step — what it is, how
its pieces fit, and then the answer it shows. The UI renders it as an interactive tour, with each
step's words in tour.json (per locale, in provisa-ui/src/i18n/). [tool-verified: comments in
demo/named/weblogs/tour.yaml, demo/named/sonnets/tour.yaml]
Structure¶
# demo/named/weblogs/tour.yaml (excerpt)
landing:
route: /sql
capability: query_development
steps:
- key: weblogsSources
route: /sources
capability: source_registration
source: shop_access
landing is where "Look around on my own" leaves the visitor. Give it a route (a path in the
UI) and the capability that gates it. Every published demo must have a landing. Provisa
format 2 added this field; a bundle built without it is refused [tool-verified:
provisa/core/demo_bundles.py:91, DEMO_FORMAT = 2].
Each step has:
| Field | Required | Meaning |
|---|---|---|
key |
yes | Unique identifier; the UI finds its text at tour.steps.<key> in tour.json |
route |
if different from previous step | The page route to open (/sources, /sql, etc.) |
capability |
if route is set |
The UI capability that gates this page |
| step type | yes | One of the types below |
Step types¶
[tool-verified: tests/unit/test_named_demo_tour.py:26-37]
| Type | Value | Page |
|---|---|---|
source |
source id from config.yaml |
Sources |
table |
<source id>.<table name> |
Tables |
relationship |
relationship alias from config.yaml |
Relationships |
example |
example name (without .graphql), from queries/ |
New query tab |
sql |
a SQL statement | SQL explorer |
api |
GET /data/rest/<domain>/<table>[?<params>] |
REST explorer |
jsonapi |
/data/jsonapi/<domain>/<table>[?<query>] |
JSON:API explorer |
grpc |
<Method>(by=[...], funcs=[...]) |
gRPC explorer |
cypher |
a Cypher query | Graph explorer |
term |
glossary term name | Glossary |
role |
role name (or all) |
SQL explorer's run-as picker |
polly |
a natural-language question | Polly panel |
A polly step is answered once when the demo's template is built; what the sandbox shows is
that stored answer. Nothing is asked live. The question must be one of the Polly bake-off's
graded questions (tests/integration/polly_bakeoff_questions.py). A demo with no stored answer
leaves the step out.
Track¶
The tour follows a settled track: the scenario and the features it shows, then how sources and
tables and relationships fit — each step on its real object — then the solution as predesigned
queries and views, then the landing page. The weblogs demo ends on /sql; the sonnets
demo ends on /graph, the echo network. [tool-verified: demo/named/weblogs/tour.yaml,
demo/named/sonnets/tour.yaml]
tests/unit/test_named_demo_tour.py checks every step: the step type is valid, the named
object exists in config.yaml, the route is a real UI route, and the capability is one the UI
gates. Fix tour authoring errors there first.
Publishing a demo¶
A demo marked published: true in its demo.yaml is built into a bundle and published.
The bundle holds: the demo's config.yaml and demo.yaml, its tour and example queries, what
its setup wrote (available in the stores' dumps), the log files the build's traffic generator
wrote, and — for a demo with replicated external sources — the seed the sandbox tier's template
is built from (seeded/). [tool-verified: scripts/demo_bundle.py module docstring,
provisa/core/demo_bundles.py module docstring]
The Demo bundles workflow (.github/workflows/demo-bundles.yml) builds a demo on a push to
main that touches demo/named/<name>/, or on a dispatch naming it. It publishes the bundle
to ghcr.io/kenstott/provisa-demos — one repository, every demo — under two tags: <name>-<version>
and <name>-latest. The version is the build's UTC minute and commit, for example
202610141530-1a2b3c4d5. A version is never published twice. [tool-verified:
provisa/core/demo_bundles.py:166-169, scripts/demo_bundle.py:409-410, .github/workflows/demo-bundles.yml]
Pulling and running a published demo¶
# latest version (default)
./start-ui-install.sh --demo weblogs
# pinned version
./start-ui-install.sh --demo weblogs@202610141530-1a2b3c4d5
# build from the checkout instead of pulling
./start-ui-install.sh --demo weblogs --from-source
# pull programmatically (in a deployment's node)
python -m provisa.core.demo_bundles pull weblogs --into ~/.provisa/demos
The launcher pulls the bundle into $PROVISA_HOME/demos/<name>/<version> (~/.provisa by
default). A version already there is not fetched again. PROVISA_DEMO_REGISTRY names another
registry; bundles come from ghcr.io/kenstott otherwise.
[tool-verified: provisa/core/demo_bundles.py:510-514]
--from-source runs demo/named/<name>/ through the full build-everything path. Combining
--from-source with @<version> is refused. Use it while authoring.
Stopping other demos' stores¶
When start-ui-install.sh --demo <name> starts, it stops every other named demo's stores first
— containers removed, volumes kept — so the ports they hold are free. The current demo's own
stores are not touched. A bundle build's compose projects (provisa-demo-bundle-*) are left
alone. [tool-verified: start-ui-install.sh:312-356, stop_other_demo_stores()]
The demo format version¶
DEMO_FORMAT = 2 [tool-verified: provisa/core/demo_bundles.py:91]. Format 2 added the tour's
landing field. A bundle built in format 1 (no landing) is refused with:
demo weblogs <version> is in demo format 1; this Provisa reads format 2:
pull its latest (start-ui-install.sh --demo weblogs)
A bundle whose requires_provisa is newer than the running Provisa is refused with:
Both refusals happen before the bundle's layer is fetched. [tool-verified:
provisa/core/demo_bundles.py:62-88, check_runs_here()]
Updating a published demo¶
Edit demo/named/<name>/ and merge to main. The workflow publishes a new version. The next
--demo <name> pull and the next sandbox on the demos page get it. No release, no redeploy.
Log files for Logs sources¶
A demo whose containers write log files can read them into tables with Logs sources.
Give the demo a logs/ directory, one subdirectory per container, each holding a .gitignore
that ignores everything but itself, so the directories are checked in empty. The containers bind
mount their subdirectory and write there; Provisa runs on the host and reads the files where they
land.
For every named demo the launcher exports PROVISA_NAMED_DEMO_DIR, the demo's directory. When the
demo has a logs/ directory, the launcher also adds it to PROVISA_LOGS_ALLOWED_ROOTS, the
directories a Logs source may read. A pristine start deletes the files under logs/ and keeps the
.gitignore files; --keep-data keeps the logs with the data. [tool-verified:
start-ui-install.sh]
A Logs source's glob is a full path. Name it under the demo's directory with the variable, which
the source keeps as written and resolves each time it reads the files [tool-verified:
provisa/logs/settings.py parse]:
# demo/named/weblogs/config.yaml (excerpt)
- id: shop_access
type: logs
cache_ttl: 30
mapping:
glob: ${env:PROVISA_NAMED_DEMO_DIR}/logs/nginx/access.json*
format: jsonl
Give a Logs source a cache_ttl: its table is a replica, re-read on that interval. In
docker-compose.yml, mount the same directories through the same variable, so a test can point
them elsewhere:
# demo/named/weblogs/docker-compose.yml (excerpt)
volumes:
- ${PROVISA_NAMED_DEMO_DIR:-.}/logs/nginx:/var/log/shop
demo/named/weblogs/ is the example. nginx in front of a small web shop writes a JSON access log,
and the shop's Postgres logs every statement with its duration as jsonlog. nginx gives each
request an id and passes it to the shop. The shop puts it in a SQLCommenter comment on every
statement, and names each request's database connection by it (application_name). The demo's
views join the two logs and the shop's tables: the slowest pages and their SQL, the requests that
failed in the database, the customers served a server error, the products viewed but never
bought, and the slow statements by table. The join between the two logs is on
application_name, a column of the database log, because tables are joined only on their columns
along a relationship. [tool-verified: demo/named/weblogs/; tests/integration/test_weblogs_demo.py]
Current published demos¶
Three demos are published [tool-verified: demo/named/*/demo.yaml]:
| Name | Title | Data stores |
|---|---|---|
weblogs |
Web shop logs | Postgres (shop database), bundled log files (nginx + Postgres statement log) |
sonnets |
Shakespeare's sonnets | Postgres (sonnets), Qdrant (line embeddings) |
files |
Instant data lake | File sources only (CSV, Parquet, Excel, JSON) — no containers at run time |
Step-by-step: build a new named demo¶
This walkthrough assumes a fictional --demo banking scenario with two local databases and one
external Snowflake source. The Snowflake source carries no local container.
1. Create the directory.
2. Write docker-compose.yml.
Include one service per local data store plus a seeder service. Add the standard labels.
Keep the database in a named volume and the seeder's marker under ${PROVISA_NAMED_DEMO_DIR:-.}
(see "Volumes" above). Expose ports on non-conflicting host ports.
x-demo-labels: &demo-labels
com.provisa.demo: banking
services:
postgresql:
image: postgres:16
labels:
<<: *demo-labels
com.provisa.demo.role: rdb
ports:
- "${PROVISA_BANKING_PG_PORT:-25700}:5432"
volumes:
- banking_pg:/var/lib/postgresql/data
healthcheck:
test: ["CMD-SHELL", "pg_isready -U provisa -d banking"]
interval: 5s
timeout: 5s
retries: 30
start_period: 30s
environment:
POSTGRES_USER: provisa
POSTGRES_PASSWORD: provisa
POSTGRES_DB: banking
seeder:
build:
context: .
dockerfile: Dockerfile.seeder
restart: "no"
labels:
<<: *demo-labels
com.provisa.demo.role: seeder
depends_on:
postgresql:
condition: service_healthy
environment:
PROVISA_BANKING_PG_HOST: postgresql
PROVISA_BANKING_PG_PORT: "5432"
volumes:
- ${PROVISA_NAMED_DEMO_DIR:-.}/data:/data-marker
volumes:
banking_pg:
The Snowflake source requires no service entry — it is external. Its credentials belong in
config.yaml via env-var interpolation.
3. Write Dockerfile.seeder.
Install only the drivers your generation scripts need.
FROM python:3.12-slim
RUN pip install --no-cache-dir psycopg2-binary
WORKDIR /app
COPY generate_postgres.py seed.py ./
ENTRYPOINT ["python", "seed.py"]
4. Write seed.py.
Check for a marker file. If present, skip. If absent, run generation scripts in order and write the marker.
import os, subprocess, sys, time
from pathlib import Path
MARKER = Path("/data-marker/.seeded")
def main():
if MARKER.exists():
print("already seeded; skipping")
return 0
t0 = time.monotonic()
subprocess.run([sys.executable, "generate_postgres.py"], check=True)
MARKER.parent.mkdir(parents=True, exist_ok=True)
MARKER.write_text(f"seeded in {time.monotonic() - t0:.0f}s\n")
return 0
if __name__ == "__main__":
raise SystemExit(main())
5. Write generate_postgres.py (and any other generate scripts).
Read host and port from env vars, with localhost + published port as the defaults. This lets the script run both from inside the seeder container and directly from the host for debugging.
import os
HOST = os.environ.get("PROVISA_BANKING_PG_HOST", "localhost")
PORT = int(os.environ.get("PROVISA_BANKING_PG_PORT", "25700"))
6. Create config.yaml.
Start the data stack and the standard demo, build the scenario in the UI (the two local databases
and the Snowflake source, their tables and relationships), export the model, and save it as
demo/named/banking/config.yaml. Add the sources you created in the UI to its sources: list by
hand, since the export omits them. Give each connection value as an env-var interpolation, and the
external Snowflake source's credentials too:
sources:
- id: banking-pg
type: postgresql
host: ${env:PROVISA_BANKING_PG_HOST:-localhost}
port: ${env:PROVISA_BANKING_PG_PORT:-25700}
database: banking
username: provisa
password: provisa
- id: banking-snowflake
type: snowflake
account: ${env:PROVISA_BANKING_SNOWFLAKE_ACCOUNT}
username: ${env:PROVISA_BANKING_SNOWFLAKE_USER}
password: ${env:PROVISA_BANKING_SNOWFLAKE_PASSWORD}
database: ${env:PROVISA_BANKING_SNOWFLAKE_DATABASE}
Every source still needs explicit tables:, which the export supplies. For a small addition to the
pet store you can ship a fragment.yaml of list sections instead of a whole config; see
Running and building demos on your laptop.
7. Write docker-compose.run.yml.
For each store the bundle will carry, write a service that loads from the build's dump. Give
every service the three host_env/port_env/port labels and publish on the loopback only.
x-demo-labels: &demo-labels
com.provisa.demo: banking
name: provisa-demo-banking-run
services:
postgresql:
image: postgres:16
restart: unless-stopped
labels:
<<: *demo-labels
com.provisa.demo.role: rdb
com.provisa.demo.host_env: BANKING_PG_HOST
com.provisa.demo.port_env: BANKING_PG_PORT
com.provisa.demo.port: "5432"
ports:
- "127.0.0.1:${BANKING_PG_PORT-25700}:5432"
volumes:
- banking_run_pg:/var/lib/postgresql/data
- ./dump/postgresql.sql:/docker-entrypoint-initdb.d/10-banking.sql:ro
healthcheck:
test: ["CMD-SHELL", "pg_isready -U provisa -d banking"]
interval: 2s
timeout: 5s
retries: 60
environment:
POSTGRES_USER: provisa
POSTGRES_PASSWORD: provisa
POSTGRES_DB: banking
volumes:
banking_run_pg:
The Snowflake source has no container here either; it is served from a replica the build landed.
8. Write demo.yaml.
title: Banking demo
description: >-
Customer accounts, transaction history and branch data from two databases and Snowflake,
joined into one governed catalog.
screenshot: card.png
published: true
requires_provisa: 0.1.0a487
Set requires_provisa to the current Provisa release, or the oldest one whose Provisa carries
every feature the demo uses.
9. Write tour.yaml.
landing:
route: /sql
capability: query_development
steps:
- key: bankingIntro
route: /sources
capability: source_registration
source: banking-pg
- key: bankingTables
route: /tables
capability: table_registration
table: banking-pg.accounts
- key: bankingJoin
route: /relationships
capability: create_relationship
relationship: HOLDS
- key: bankingAnswer
route: /sql
capability: query_development
sql: >-
SELECT region, COUNT(*) AS accounts, SUM(balance) AS total_balance
FROM banking.accounts GROUP BY region ORDER BY total_balance DESC
- key: bankingDone
route: /sources
capability: source_registration
source: banking-pg
Add a line per key to provisa-ui/src/i18n/en/tour.json (and the other locales if you
translate the tour).
10. Bring the stack up and test.
Watch docker compose logs seeder to confirm generation finishes and the marker is written.
11. Start Provisa with the named demo.
The launcher brings the compose stack up and waits for the seeder, uses config.yaml in place of the
standard demo config, and prints Config for named demo 'banking': .... The stack in step 10 can be started first for
testing, but unless you pass --keep-data the launcher removes it and seeds it again.
12. Mark it published and submit.
When the demo is ready, set published: true in demo.yaml and merge to main. The workflow
builds and publishes the bundle automatically.
Log files for Logs sources¶
A demo whose containers write log files can read them into tables with Logs sources (REQ-1996).
Give the demo a logs/ directory, one subdirectory per container, each holding a .gitignore
that ignores everything but itself, so the directories are checked in empty. The containers bind
mount their subdirectory and write there; Provisa runs on the host and reads the files where they
land.
For every named demo the launcher exports PROVISA_NAMED_DEMO_DIR, the demo's directory. When the
demo has a logs/ directory, the launcher also adds it to PROVISA_LOGS_ALLOWED_ROOTS, the
directories a Logs source may read. A pristine start deletes the files under logs/ and keeps the
.gitignore files; --keep-data keeps the logs with the data. [tool-verified:
start-ui-install.sh]
A Logs source's glob is a full path. Name it under the demo's directory with the variable, which
the source keeps as written and resolves each time it reads the files [tool-verified:
provisa/logs/settings.py parse]:
# demo/named/weblogs/config.yaml (excerpt)
- id: shop_access
type: logs
cache_ttl: 30
mapping:
glob: ${env:PROVISA_NAMED_DEMO_DIR}/logs/nginx/access.json*
format: jsonl
Give a Logs source a cache_ttl: its table is a replica, re-read on that interval. In
docker-compose.yml, mount the same directories through the same variable, so a test can point
them elsewhere:
# demo/named/weblogs/docker-compose.yml (excerpt)
volumes:
- ${PROVISA_NAMED_DEMO_DIR:-.}/logs/nginx:/var/log/shop
The --source mechanism: what it is not¶
--source=<name> adds a single source from demo/sources/<name>/ to the standard demo. Each
source in that directory carries its own fragment.yaml and a prime.py that seeds a small
toy dataset. The launcher starts and stops those containers. [tool-verified, start-ui-install.sh:37]
Named demos deliberately do not follow that pattern. Their data is large, meant to persist
across restarts, and they manage their own compose lifecycle. start-ui-install.sh --demo <name>
starts the named demo's stack on every launch. By default it first removes the stack's containers and
volumes and deletes its data/ directory (docker compose down -v), so the seeder reseeds from
empty; --keep-data skips that and reuses the data from the last seeding. The launcher never stops
the stack: stopping it is yours to do. See Running and building demos on your
laptop [tool-verified from start-ui-install.sh:285-310].
You can combine both: ./start-ui-install.sh --demo perf --source=cassandra adds a toy
Cassandra source on top of the perf demo. The two mechanisms are additive.