Webview

Our webview complements REST API endpoints with web-based services to handle sensitive or complex operations:

• add a connection (to a bank or a provider), or edit/repare access to a connection;

• manage connections (add/remove/edit);

• edit and validate bank transfers.

Usage of the webview is mandatory if you don't hold an Agent status, since you are not allowed to use API endpoints carrying user credentials, and optional otherwise.

You can use our integration demos to experiment with the different Webview flows described below.

Webview protocol

Services available as part of the webview are designed as parameterized URLs intended to be opened in a web browser. A callback URI must be specified by callers to be notified at the end of the operation flow, similar to OAuth 2 specification.

Base URL

The base URL of all services must be customized: https://webview.powens.com/{lang}/{flow}?domain={domain}.biapi.pro&{parameters}

• {domain}: substitute with your API domain in the domain query parameter

• {lang}: optionally specify the language of the webview (possible values: en, fr, de, nl, it, es; if not specified, an automatic redirection will be performed following the language of the browser).

• {flow}: See endpoints reference below for details about each flow

• {parameters}: See endpoints reference below for details about query parameters

Callback handling

Most flows redirect to a callback URI at the end of the process. Query parameters are added to the URI to identify successful or failed operations.

Successful parameters are specific to each flow. In case of an error, the following parameters are added:

Parameter	Description
error	An lowercase string error code identifying the kind of error that occurred. When the parameter is not present, the response is successful.
error_description	A longer string description of the error (not intended for user display).

Common error codes include:

Code	Description
access_denied	The user explicitly cancelled the flow.
server_error	Oops, a technical failure occurred during the process.

Forward compatibility requirement: additional error codes may be added in the future to describe specific cases. When implementing error codes handling, always fallback to a generic case for unknown codes.

Browser compatibility

The webview is designed and tested to work with browsers supported by the Angular framework: https://angular.io/guide/browser-support

Privacy / GDPR status

The webview itself does not use any kind of long-term data persistence mechanism such as cookies or local storage, but some authentication or authorization steps may delegate to third-party web services that may implement them. Analytics performed on the webview use anonymous data only.

Integration guidelines

Presenting the webview URL in a browser requires special care about the technical components involved, in order to optimize UX and conversion rate by allowing app-to-app experiences.

The recommended components vary by platform:

Web

In a web environment (i.e. when your own app is already running in a browser, as a standard HTML/JS app, PWA, etc.), you should present the webview either using a full-page redirect (recommended), or optionally using a popup window.

The later requires special care on mobile as popups are usually presented as new tabs, and can be subject to blocking policies. Such integrations also require proper cross-window communication to dismiss the extra window after the flow has ended.

Integration of our webview in an <iframe> tag is discouraged as it can yield to a mixed user experience (our webiew provides its own UI context and navigation).

Iframe integration can also prevent app-to-app support for some connectors. When our webview is embedded in an iframe and it needs to present a third-party connection flow (connector webview with potential app-to-app support), it will itself open a popup (or new tab) to maximize the chance of app-to-app support.

When using the redirection technique, make use of the state parameter, optionally in conjunction with session storage, to restore context in your app at the end of the webview flow.

Android

In a native Android environment (or when your app is compiled to an Android app using a multi-platform framework), you should present our webview using the Chrome Custom Tabs library, rather than using a WebView component.

Android Custom Tabs Overview - Chrome DevelopersChrome Developers

Chrome Custom Tabs allow good support for app-to-app experiences and let the end-user benefit from a navigation context shared with the browser app (cookies, saved credentials, etc.). Although they represent a slightly less integrated visual experience, the library does support customization and theming.

WebView component should be avoided as it can prevent app-to-app support for some connectors.

Callback handling with Chrome Custom Tabs usually rely on declaring an intent filter (with custom scheme) handled by the calling Activity, which is brought to foreground after the flow.

iOS

In a native iOS environment (or when your app is compiled to an iOS app using a multi-platform framework), you should present our webview using the SFSafariViewController component, rather than using a WKWebView component.

SFSafariViewController | Apple Developer DocumentationApple Developer Documentation

SFSafariViewController allows good support for app-to-app experiences and let the end-user benefit from a navigation context shared with the browser app (cookies, saved credentials, etc.). Although they represent a slightly less integrated visual experience, the component does support customization and theming.

WKWebView component should be avoided as it can prevent app-to-app support for some connectors.

Callback handling with SFSafariViewController usually rely on defining a custom URL scheme and dismissing the controller in the handler.

Multi-platform frameworks

When using Flutter, use the flutter_custom_tabs package, that implement the above recommended components.

When using React Native, you can rely on some (non official) third-party packages to implement usage of Chrome Custom Tabs and SFSafariViewController, or provide your own native module.

Endpoints reference

Add connection flow

https://webview.powens.com/{lang}/connect?domain={domain}.biapi.pro&{parameters}

This flow allows an end-user to add a new connection to the API. The flow handles the following steps:

• selecting a connector;

• authenticating & authorizing with the connector, by collecting credentials or delegating;

• managing consent to aggregate accounts/subscriptions;

• collecting required information for professional accounts.

You can try it out here.

Query parameters

Parameter	Required	Description
domain	Yes	Your API domain. For instance: example.biapi.pro
client_id	Yes	The ID of the requesting client application. You can manage client applications of your domain in the admin console.
redirect_uri	Yes	An absolute callback URI. The webview will redirect to it at the end of the flow.
code	No	A user-scoped temporary code to use with our API. If you don't provide a code, a new anonymous user will be created before the connection is added, and you will be returned an access token code scoped to it with the success callback.
state	No	An opaque string parameter that you can use to carry state across the flow. The parameter will be set "as is" on the callback URI. Make sure that the state you provide is properly URL-encoded.
connector_ids	No	A comma-separated list of connector IDs available to pick from. If the parameter is omitted, all active connectors are available. If you pass a single value, the user is not prompted to choose the connector. The parameter is combined with connector_uuids.
connector_uuids	No	A comma-separated list of connector UUIDs available to pick from. If the parameter is omitted, all active connectors are available. If you pass a single value, the user is not prompted to choose the connector. The parameter is combined with connector_ids.
connector_capabilities	No	A comma-separated list of capabilities to filter available connectors. If the parameter is omitted, bank is inferred. If multiple values are provided, only connectors that expose all the requested capabilities are available. To request a bank connection, use bank. To request a provider connection, use document.
account_ibans	No	A comma-separated list of IBANs to filter accounts available for activation in a bank connection context. Other accounts will be disabled.
account_types	No	A comma-separated list of account types to filter accounts available for activation in a bank connection context. Other accounts will be disabled. To use the Webview in bank-only mode, specify account_types=checking,card as a URL parameter.
max_connections	No	A positive number indicating the maximum number of consecutive connections a user is allowed to add within the same connect flow. If this parameter is greater than one, a new screen will appear in the Webview, prompting the user to decide whether to add another institution or not. By enabling this multiple addition, you must also handle a new successful callback parameter connection_ids in your integration.
{connector_uuid}.{field.name}={value}	No	Combine a connector UUID with one of its fields' name to prefill or preselect the value of this field. Example: you can use f5c29767-1bc8-5337-9e4e-68a0fbd91c9a.website=pro in order to preselect the website field with pro value for the connector with the specified UUID (Société Générale in this example).

Successful callback parameters

Parameter	Description
connection_id	The ID of the newly created connection. Please note that when redirecting to the callback URI, the accounts and/or subscriptions are available in the API, but bank transactions or documents may still be syncing in background.
code	Optional. If a code was not initially specified, an API code that you must exchange to obtain a permanent access token associated with the newly-created anonymous user holding the connection. The parameter is URL-encoded, make sure to handle it accordingly.
state	Optional. Identical to the state parameter that was initially specified.
connection_ids	The IDs of the newly created connections. Please note that when redirecting to the callback URI, the accounts and/or subscriptions are available in the API, but bank transactions or documents may still be syncing in background.

Additional error codes

Code	Description
tos_declined	The end-user refused to validate the terms of service.

Re-auth / edit connection credentials flow

https://webview.powens.com/{lang}/reconnect?domain={domain}.biapi.pro&{parameters}

This flow allows an end-user to re-authenticate against a bank or a provider in order to recover an existing connection, or to completely reset credentials associated with a connection.

You can try it out here.

Query parameters

Parameter	Required	Description
domain	Yes	Your API domain. For instance: example.biapi.pro
client_id	Yes	The ID of the requesting client application. You can manage client applications of your domain in the admin console.
redirect_uri	Yes	An absolute callback URI. The webview will redirect to it at the end of the flow.
code	Yes	A user-scoped temporary code to use with our API.
connection_id	Yes	The ID of the existing connection.
state	No	An opaque string parameter that you can use to carry state across the flow. The parameter will be set "as is" on the callback URI. Make sure that the state you provide is properly URL-encoded.
reset_credentials	No	In the default mode (false), the service will try to recover the connection and prompt the user only with outdated or transient information (new password, OTP...). Set the parameter to true to force resetting all the credentials associated with the connection. This parameter may not apply to all connectors.

Successful callback parameters

This flow adds no parameter to the callback URI in case of success, except from state.

Manage connections

https://webview.powens.com/{lang}/manage?domain={domain}.biapi.pro&{parameters}

This flow allows an end-user to manage the connections associated with his account in the API. The user can add new connections, remove existing ones, fix connection errors, reset credentials or activate/deactivate bank accounts.

Support of redirect_uri in this flow is optional, as it can be integrated or presented as a terminal step, without relying on a final redirection.

You can try it out here.

Query parameters

Parameter	Required	Description
domain	Yes	Your API domain. For instance: example.biapi.pro
client_id	Yes	The ID of the requesting client application. You can manage client applications of your domain in the admin console.
code	Yes	A user-scoped temporary code to use with our API.
connection_id	No	The ID of an existing connection. When provided, the webview will directly navigate to that connection if it is found among the retrieved connections.
redirect_uri	No	An absolute callback URI. When provided, the webview will display a close button that redirects to it.
state	No	An opaque string parameter that you can use to carry state across the flow when providing a redirect_uri. The parameter will be set "as is" on the callback URI. Make sure that the state you provide is properly URL-encoded.
connector_capabilities	No	A comma-separated list of capabilities to filter available connectors when adding a new connection. If the parameter is omitted, bank is inferred. If multiple values are provided, only connectors that expose all the requested capabilities are available. To request a bank connection, use bank. To request a provider connection, use document.
account_types	No	A comma-separated list of account types to filter accounts available for activation on adding a new bank connection or updating existing connections. Other accounts will be disabled.

Callback parameters

This flow adds no parameter to the callback URI, except from state.

Validate a payment

https://webview.powens.com/{lang}/payment?domain={domain}.biapi.pro&{parameters}

This flow allows an end-user to validate a payment request. The flow handles the following steps:

• present a list of supported emitter banks;

• validate the payment request and redirect the user to the validation webview of the bank.

Query parameters

Parameter	Required	Description
domain	Yes	Your API domain. For instance: example.biapi.pro
client_id	Yes	The ID of the requesting client application. You can manage client applications of your domain in the admin console.
redirect_uri	Yes	An absolute callback URI. The webview will redirect to it only in case of an error or cancellation.
code	Yes	A payment-scoped service token to use with our API. The provided token must have the payments scope.
state	No	An opaque string parameter that you can use to carry state across the flow. The parameter will be set "as is" on the callback URI. Make sure that the state you provide is properly URL-encoded.
payment_id	Yes	The ID of the payment request that was prepared with the API.

Successful behavior

Unlike other webview endpoints, the user will be redirected to the callback URL provided at the creation of the payment request (using client_redirect_uri) after the bank webview. The redirect_uri provided as a webview parameter is only used for the error or cancellation cases.

(Deprecated) Execute a bank transfer

Since the release of our Pay product (handling PSD2-compliant use-cases), the former Transfer product (based on directaccess) has been deprecated. The Transfer product is neither maintained nor offered anymore.

https://{domain}.biapi.pro/2.0/auth/webview/{lang}/transfer

This flow allows an end-user to execute a bank transfer. The flow handles the following steps:

• if the transfer is not already created, all steps to authenticate with a bank, select the recipient, the emitter account, the amount and label;

• executing the transfer, including managing SCAs for recipient registration and/or transfer validation.

Query parameters

Parameter	Required	Description
client_id	Yes	The ID of the requesting client application. You can manage client applications of your domain in the admin console.
redirect_uri	Yes	An absolute callback URI. The webview will redirect to it at the end of the flow.
code	Yes	A user-scoped temporary code to use with our API. If you don't provide a code, a new anonymous user will be created before a connection is added and the transfer is executed, and you will be returned an access token code scoped to it with the success callback.
state	No	An opaque string parameter that you can use to carry state across the flow. The parameter will be set "as is" on the callback URI. Make sure that the state you provide is properly URL-encoded.
transfer_id	No	The ID of an prepared transfer to be validated in the webview. The user cannot edit anything on the transfer before validation.

Successful callback parameters

Parameter	Description
transfer_id	The ID of the transfer that was created and executed.
code	If a code was not initially specified, an API code that you can exchange to obtain a permanent access token associated with the newly-created anonymous user holding the transfer. The parameter is URL-encoded, make sure to handle it accordingly.
state	Identical to the state parameter that was initially specified (if any).

If you need to perform actions when a connection is added or removed, you should rely on webhooks.