Render Certificate of Authenticity

Generates the official PDF certificate after an artwork passes verification. This certificate is required before artwork can be listed for sale on the platform. Call this after `isCanvasSigned()` confirms the canvas signature and `image_phash()` has stored the artwork's fingerprint.

For batch certification of multiple artworks, pass a shared database connection via the `cn` parameter to avoid connection overhead.

Usage

renderCertificate(
  artist,
  artwork,
  which_templ = NULL,
  which_frame = NULL,
  outdir = NULL,
  new_utc = NULL,
  saveDB = FALSE,
  saveCDN = FALSE,
  clean = TRUE,
  cn = NULL
)

Arguments

artist

Character. The artist's UUID (format: `746bxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx`). Obtain from `artutils::get_artist_by_slug()` or the `artist_uuid` column in artist queries. Identifies which artist's artwork is being certified.

artwork

Character. The artwork's UUID (format: `99xxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx`). The `99` prefix indicates platform-authenticated artworks. Obtain from artwork queries or `artutils::genArtworkID()` for new uploads.

which_templ

Integer. Certificate template design number (1 to 9). Each number corresponds to a different visual design stored on CDN. If NULL (default), randomly selected for variety across certificates.

which_frame

Integer. Certificate frame style number (1 to 20). Determines the decorative border around the artwork image. If NULL (default), randomly selected.

outdir

Character. Output directory for generated files. Must be an empty directory or non-existent (will be created). Defaults to a temp directory if NULL. Use for custom output locations or to inspect intermediate files.

new_utc

POSIXct. Timestamp in UTC timezone for the certificate. Use `Sys.time()` for current time or a specific POSIXct value for backdating corrections. Displayed on the certificate and stored in database.

saveDB

Logical. Whether to persist the certificate record to the database. When TRUE, requires valid database credentials via environment variables. When FALSE (default), generates certificate without database side effects - useful for previewing or testing before final generation.

saveCDN

Logical. Whether to upload the PDF and JPEG to CDN. When TRUE, certificate becomes publicly accessible at the returned URL. When FALSE (default), files remain in local `outdir` only.

clean

Logical. Whether to remove intermediate files (LaTeX source, template images) after rendering. Default TRUE keeps output directory clean. Set FALSE to inspect intermediate files for debugging or custom post-processing.

cn

Database connection object (class `PqConnection` from {RPostgres}). If NULL (default), creates a new connection via `artcore::dbc()` and closes it on function exit. Pass an existing connection for batch operations to avoid repeated connection overhead. Caller responsible for closing passed connections.

Value

data.table with certificate details:

artist_uuid

Artist identifier

art_uuid

Artwork identifier

cert_id

Formatted certificate ID (e.g., "000-000-123")

template_id

Template number used

frame_id

Frame number used

created_utc

Certificate creation timestamp

path_pdf

CDN URL to PDF certificate

path_jpeg

CDN URL to JPEG preview

Details

Certificate generation requires: - Valid artist/artwork UUIDs with verification record in database - LaTeX installation (tinytex/lualatex) - CDN access for template/frame assets

The function: 1. Retrieves artwork metadata from database 2. Downloads template and frame assets from CDN 3. Composites framed artwork image 4. Renders LaTeX template with artwork data 5. Generates PDF and JPEG outputs 6. Optionally saves to database and uploads to CDN

Examples

if (FALSE) { # \dontrun{
# Generate certificate without saving
cert <- renderCertificate(
  artist = "artist-uuid-here",
  artwork = "artwork-uuid-here"
)

# Generate and persist to database/CDN
cert <- renderCertificate(
  artist = "artist-uuid-here",
  artwork = "artwork-uuid-here",
  saveDB = TRUE,
  saveCDN = TRUE
)

# Use specific template and frame
cert <- renderCertificate(
  artist = "artist-uuid-here",
  artwork = "artwork-uuid-here",
  which_templ = 1,
  which_frame = 3
)
} # }