The resource proofs endpoint allows you to create a final rendering of any template. This is best practice to ensure that you are visually validating your creative before any mail pieces use the template. The API provides endpoints for creating, updating, and retrieving template proofs.back to top
Lob.com Resource Proofs API declares
1 security scheme
for authenticating requests.
It accepts HTTP basic authentication (basicAuth).
By default, every request must be authenticated.
Paths & Operations 3
Across 2 paths, the API surfaces 3 operations — 1 GET, 1 PATCH, 1 POST. Each is listed below with its method, path, parameters, and response codes.
Resource Proofs 3
The resource proofs endpoint allows you to create a final rendering of any template. This is best practice to ensure that you are visually validating your creative before any mail…
GET
/resource_proofs/{res_prf_id}
Retrieve
resource_proof_retrieve1 param→ 200default
PATCH
/resource_proofs/{res_prf_id}
Update
resource_proof_update1 parambody→ 200default
POST
/resource_proofs
Create
resource_proof_createbody→ 201default
Schemas 46
The contract defines 46 schemas that model the data the API accepts and returns. The most detailed are resource_proof_base (6 properties), address_fields_us (5 properties), address_fields_intl (5 properties), thumbnail (3 properties). Each schema is shown below with its type and property counts.
tmpl_id
string
Unique identifier prefixed with tmpl. ID of a saved [HTML template](section/HTML-Templates).
letter_resource_parameters
error
object
Lob uses RESTful HTTP response codes to indicate success or failure of an API request. In general, 2xx indicates success, 4xx indicate an input error, and 5xx…
1 property1 required
double_sided
boolean
Set this attribute to true for double sided printing, or false for for single sided printing. Defaults to true.
resource_proof_editable
2 required
company
stringnull
Either name or company is required, you may also add both. Must be no longer than 40 characters. If both name and company are provided, they will be printed on…
local_file_path
string
The path to a local file.
signed_link
string
A [signed link](section/Asset-URLs) served over HTTPS. The link returned will expire in 30 days to prevent mis-sharing. Each time a GET request is initiated, a…
inline_address
input_from
object
1 property
color
boolean
Set this key to true if you would like to print in color. Set to false if you would like to print in black and white.
html_string
string
An HTML string of under 10,000 characters.
metadata
object
Use metadata to store custom information for tagging and labeling back to your internal systems. Must be an object with up to 20 key-value pairs. Keys must be…
failure_status_code
integer
A conventional HTTP status code: 401 - Authorization error with your API key or account 403 - Forbidden error with your API key or account 404 - The requested…
adr_id
string
Unique identifier prefixed with adr.
postcard_size
string
Specifies the size of the postcard. Only 4x6 postcards can be sent to international destinations.
address_placement
string
Specifies the location of the address information that will show through the double-window envelope. To see how this will impact your letter design, view our l…
date_created
string
A timestamp in ISO 8601 format of the date the resource was created.
ltr_size
string
Specifies the size of the letter. It accepts two values usletter and uslegal. If the [Lob-Version header](tag/Versioning-and-Changelog) in the request is set t…
address_editable_intl
resource_description
stringnull
An internal description that identifies this resource. Must be no longer than 255 characters.
inline_address_us
address_editable_us
date_modified
string
A timestamp in ISO 8601 format of the date the resource was last modified.
inline_address_intl
res_prf_status
string
The processing status of the resource proof.
address_fields_us
object
5 properties4 required
ltr_file
Notes: - HTML merge variables should not include delimiting whitespace. - All pages of a supplied PDF file must be sized at 8.5"x11", while supplied HTML will…
postcard_resource_parameters
psc_back
The artwork to use as the back of your postcard. Notes: - HTML merge variables should not include delimiting whitespace. - PDF, PNG, and JPGs must be sized at…
psc_front
The artwork to use as the front of your postcard. Notes: - HTML merge variables should not include delimiting whitespace. - PDF, PNG, and JPGs must be sized at…
country_extended
string
Must be a 2 letter country short-name code (ISO 3166). Does not accept US, AS, PR, FM, GU, MH, MP, PW, or VI. For these addresses, please use the US verificati…
res_prf_resource_type
string
The type of resource to generate a proof for.
input_from_us
object
1 property
resource_proof_base
object
6 properties
address_fields_intl
object
5 properties2 required
remote_file_url
string
The location of a remote file. Remote URLs have a 5 MB file size limit and must be downloaded within 40 seconds.
self_mailer_size
string
Specifies the size of the self mailer. The 17.75x9trifold size is in beta. Contact support@lob.com or your account contact to learn more.
res_prf_id
string
Unique identifier prefixed with resprf.
input_to
object
1 property
issue_entry
object
3 properties2 required
self_mailer_resource_parameters
resource_proof
thumbnail
object
3 properties
merge_variables
objectnull
You can input a merge variable payload object to your template or QR code redirect URLs to render dynamic content. For example, if you have a template like: {{…
resource_proof_updatable
object
1 property
Specification
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