Links

A consent link is a pre-authenticated URL that creates a consent event when it gets accessed from a browser. Consent links can be used to show or send users links that they can click to update their consent status. This includes use cases like unsubscribing from all communications in an email, sending a confirmation email with an action button, etc.

We support two types of authorization for consent links:

• Pre-authorized: Consent links are pre-created by calling the Didomi API and include a unique signed token in the URL. This requires an API request to create the consent link. This is the recommended way to create consent links.

• Digest: Consent links are created on-the-fly and include a unique hash digest or HMAC signature to authenticate them. This does not require a request to the Didomi API and consent links can be generated entirely on your server. This is useful for environments where sending HTTP requests is complicated (emailing providers, for instance).

Consent links with pre-authorization

To create a consent link for a user, send a POST request to https://api.didomi.io/consents/links?organization_id=<ID of your organization> and specify the following parameters in the body:

Property	Description
organization_user_id	Organization user ID that a consent event should be created for when the link gets executed
action	Action to execute when a user loads the consent link in a browser. Must be event.create or event.update.
event	Theconsent event to create or update when a user loads the consent link in a browser.
redirect_url	The URL to redirect the user to after loading the consent link and executing the action. This allows the user to end up on a page that you own.
lifetime	Lifetime of the consent link in seconds. The consent link automatically expires after that duration and becomes unusable. Defaults to 15 minutes (900 seconds).

Example:

POST https://api.didomi.io/consents/links?organization_id=<ID of your organization>
{
    "organization_user_id": "<User ID>",
    "action": "event.create",
    "event": {
        "consents": {
            "purposes": [
                ...Update to purposes
            ]
        }
    },
    "redirect_url": "https://www.ourwebsite.com"
}

The API will respond with the created link in the url field:

{
    "organization_user_id": "<User ID>",
    "action": "event.create",
    "event": {
        "consents": {
            "purposes": [
                ...Update to purposes
            ]
        }
    },
    "redirect_url": "https://www.ourwebsite.com",
    "url": "https://api.privacy-center.org/consents/execute/..."
}

The created link includes a unique token. When loaded in a browser, the corresponding event will be created or updated without any other authentication required.

The /consents/links endpoint of the API is used to create consent links. For a full reference of the endpoint and the resources that it returns, visit https://api.didomi.io/docs/.

Action and event

When executing a consent link, the Didomi API will execute the action that is defined in the action parameter of the consent link. That action can be either creating a new consent event (event.create) or updating an existing consent event (event.update).

Creating an event

The event to create must be specified in the event parameter. The event schema is the standard Didomi consent event schema.

For instance, to unsubscribe a user from a purpose, you could send the following JSON event:

{
    "consents": {
        "purposes": [{
            "id": "purpose_id",
            "enabled": false
        }]
    }
}

Any event that can be created through the regular POST /consents/events API can be created with a consent link with the same structure.

Updating an event

The event to update must be specified in the event parameter. The event schema is the standard Didomi consent event schema. An id field must be specified with the ID of an existing consent event to update. The other properties specified in the event parameter will be merged into the event.

For instance, to confirm an event that was previously in status pending_approval, you could send the following object:

{
    "id": "ddd2a1cd-589d-4f44-98f5-0b828a1c2a36",
    "status": "confirmed"
}

Consent links with digest authorization

Digest authorization allows you to specify all the parameters of a consent link (organization user ID, event to create/update, etc.) in the query-string parameters of a URL. To authorize that request, you must add a digest computed from the organization user ID and a secret shared with Didomi. This ensures that the request originates from your servers and cannot be freely created.

When using digest authorization, you must build the consent link URL yourself from scratch. The base of the URL is https://api.privacy-center.org/v1/consents/execute to which you can add the query-string parameters that form your consent link. Example of a consent link with digest authorization: https://api.privacy-center.org/v1/consents/execute?key=fe295974-e126-49a4-9d6f-84bc5884c298&auth_algorithm=hash-md5&auth_sid=secret-id&auth_digest=e067d565e248267d5c3dd2f82409f5e3&auth_salt=salt&organization_user_id={organization_user_id}&action=event.create&event=%7B%22consents%22%3A%7B%22purposes%22%3A%5B%7B%22id%22%3A%22purpose_id%22%2C%22enabled%22%3Afalse%7D%5D%7D%7D&redirect_url=https%3A%2F%2Fwebsite.com

This link is composed of the following parameters:

Parameter	Description
key	The Public API key of your organization (from the Console).
auth_algorithm	The method and algorithm used for generating the digest.
auth_sid	ID of the secret used for generating the digest.
auth_digest	Digest computed from the organization user ID and secret value.
auth_salt (optional)	The salt used for computing the digest.
organization_user_id	The organization user ID for which an event will be created or updated
action	The action to run when executing the consent link. This could be either event.create (for creating an event) or event.update (for updating an existing event).
event	The event to create or update as URL-encoded JSON object. If the event is being updated (action is event.update), an id field must be provided to indicate what event is being updated.
redirect_url (optional)	The URL to redirect to after executing the consent link. No redirect URL will show a blank page to the user.

Read on for more information on every parameter and how they are built.

Digest

Digest and algorithm (auth_algorithm and auth_digest)

The digest is a hex-encoded string computed by running a hash or HMAC algorithm on the concatenated organization_user_id and secret. The digest must be provided in the auth_digest query-string parameter of the consent link.

For example and assuming your organization user ID is [e-mail] and your secret value is secret_value, you could compute a MD5 hash digest as MD5([e-mail]_value) = 2d7d57c0b588a5c4bc508b17ace5fd7e. Note that there is no separator between the organization user ID and the secret.

We support the following digest types and algorithms:

Type	Algorithm	ID (auth_algorithm)
Hash	MD5	hash-md5
Hash	SHA1	hash-sha1
Hash	SHA256	hash-sha256
HMAC	SHA1	hmac-sha1
HMAC	SHA256	hmac-sha256

We recommend using Hash / SHA256 or HMAC / SHA256 if possible. The algorithm that you will be using must be provided in the auth_algorithm query-string parameter of the consent link.

Secret (auth_secret)

The digest is used as a proof that the consent link was created by your organization and not by a third-party generating a consent link for your users without authorization. For the digest to be a valid proof, it needs to include a unique secret value only known by Didomi and your organization. When the Didomi API receives a consent link with a digest, it re-computes the digest and compares it with the provided digest. If the digests match, the consent link was created by an organization that knows the secret value associated with the consent link.

For Didomi to be able to compute the digest, you must specify the ID of the secret value that was used for computing the digest on your side. To do so, specify the auth_sid query-string parameter with the ID (not the secret value itself) of the secret used for the digest.

You can create and manage secrets by reading our documentation.

Salt (auth_salt) - Optional

To further improve the security of the secret, you can include a random unique salt in every consent link that you create. The digest should then be computed on the organization user ID, the secret, and the salt.

For example and assuming your organization user ID is [e-mail] , your secret value is secret_value, and your salt is salt, you could compute a MD5 hash digest as MD5([e-mail]) = e067d565e248267d5c3dd2f82409f5e3. Note that there is no separator between the organization user ID, the secret, and the salt.

The salt must be provided in plain-text in the auth_salt query-string parameter of the consent link. The salt is not secret and it is safe to pass it unencrypted. The salt is present to increase the uniqueness of the digest and make it harder for attackers to guess the secret with pre-computed hash attacks. We recommend generating a new random salt for every consent link that you create.

Action and event

When executing a consent link, the Didomi API will execute the action that is defined in the action query-string parameter of the consent link. That action can be either creating a new consent event (event.create) or updating an existing consent event (event.update).

Creating an event

The event to create must be specified as a URL-encoded JSON consent event in the event query-string parameter. The event schema is the standard Didomi consent event schema.

For instance, to unsubscribe a user from a purpose, you could send the following JSON event:

{
    "consents": {
        "purposes": [{
            "id": "purpose_id",
            "enabled": false
        }]
    }
}

URL-encoded to fit in a query string, you would get:

%7B%22consents%22%3A%7B%22purposes%22%3A%5B%7B%22id%22%3A%22purpose_id%22%2C%22enabled%22%3Afalse%7D%5D%7D%7D

Any event that can be created through the regular POST /consents/events API can be created with a consent link with the same structure.

Updating an event

The event to update must be specified as a URL-encoded JSON consent event in the event query-string parameter. The event schema is the standard Didomi consent event schema. An id field must be specified with the ID of an existing consent event to update. The other properties specified in the event parameter will be merged into the event.

For instance, to confirm an event that was previously in status pending_approval, you can could send the following JSON:

{
    "id": "ddd2a1cd-589d-4f44-98f5-0b828a1c2a36",
    "status": "confirmed"
}

Redirection

You can provide a URL to redirect the user to after executing the action via the redirect_url query-string parameter for digest authorization, and via the redirect_url body parameter for pre-authorization.

If an error happens while executing the action, Didomi will append an error query-string parameter to the redirection URL. The error parameter will contain an error code and can be used to show an error message to the user to let them know that their action has failed.

Example

If the provided redirect URL is https://www.ourwebsite.com/consent-updated, then:

• Didomi will redirect to https://www.ourwebsite.com/consent-updated if the action is successful

• Didomi will redirect to https://www.ourwebsite.com/consent-updated?error=[ERROR CODE] if the action fails to execute

Error codes

The error query-string parameter will contain one of the following error codes:

Code	Description	Link type
MISSING_OID	The organization_id parameter is missing.	Digest
MISSING_SID	The auth_sid parameter is missing.	Digest
INVALID_SID	The auth_sid parameter is not a valid secret ID. Double check that the secret exists on the Didomi platform and that the ID is valid.	Digest
INVALID_ALG	The auth_algorithm parameter is invalid. Ensure that it is one of the values listed in our documentation.	Digest
INVALID_DIGEST	The auth_digest parameter provided does not match the digest that we computed. Ensure that the secret, algorithm, and salt are all valid.	Digest
MISSING_ACTION	The action query-string parameter is missing.	Digest
MISSING_OUID	The organization_user_id query-string parameter is missing.	Digest
INVALID_OUID	The organization user ID provided in theorganization_user_id query-string parameter is invalid. The action will still be executed in this case.	Digest
MISSING_EVENT	The event query-string parameter is missing.	Digest
INVALID_EVENT	The data provided in the event query-string parameter is not a valid JSON string.	Digest
MISSING_EVENT_ID	The event provided does not include an event ID (if the action is event.update).	Digest, Pre-auth
UNKNOWN	An unknown error happened.	Digest, Pre-auth
UNSUPPORTED_ACTION	The action provided is not supported. We currently support event.create and event.update actions.	Digest, Pre-auth
MISSING_TOKEN	An action token must be provided in the URL.	Pre-auth
INVALID_TOKEN	The token provided in the URL is not a valid JWT token created by the Didomi platform.	Pre-auth