The reporter (#160) saw `USER_PROJECT_DENIED` raw in the CLI because
all three CLI error-rendering paths flatten typed BqAccessError /
guardrail / RBAC dicts to a truncated single-line string, hiding the
structured `hint` field that explains how to fix the misconfig.
Fix: shared `cli/error_render.py:render_error(status_code, body)` that
recognizes the canonical typed shapes and pretty-prints them. Falls
back to truncated-and-flattened form for unrecognized bodies, so the
renderer never makes worse-than-status-quo output.
Recognized shapes:
- {detail: {kind: ..., hint?, billing_project?, data_project?}}
— typed BqAccessError responses from /api/v2/scan, /sample, /schema,
/api/query (when /api/query escalates a BQ failure)
- {detail: {reason: 'remote_scan_too_large', scan_bytes, limit_bytes,
tables, suggestion}} — new /api/query cost-guardrail rejection
- {detail: {reason: 'bq_path_not_registered'/'bq_path_access_denied',
path, hint?, registered_as?}} — new /api/query RBAC patch
- {detail: '...'} — string detail (legacy endpoints)
Wired through 3 CLI paths:
- cli/v2_client.py: V2ClientError.__str__ delegates to render_error;
pre-truncation removed from V2ClientError.message (was hiding hints
past 200 chars).
- cli/commands/query.py:_query_remote: parse JSON body, call renderer
on error.
- cli/commands/query.py:_query_hybrid: catch RemoteQueryError, build
synthetic `{detail: {kind: error_type, **details}}` payload, render.
tests/test_cli_query.py:test_remote_query_failure: assertion updated
from `"Query failed"` (no longer printed) to `HTTP 400` + `bad SQL`
(what the renderer surfaces for string detail).
Sample output for cross_project_forbidden:
Error: cross_project_forbidden (HTTP 502)
billing_project: (empty)
data_project: prj-example-data-001
message: USER_PROJECT_DENIED on bigquery.googleapis.com
hint: Set data_source.bigquery.billing_project in
/admin/server-config to a project where the SA has
serviceusage.services.use, or grant the SA that role on the
data project.
19 tests pass — 10 from T4a now GREEN + 3 prior cli_query tests still
green + 6 ancillary.
