# Launching the Plugin

The plugin window is launched with `open(options)` method:

```javascript
OzLiveness.open({
// omit session_token if your SDK version is older than 1.9.2 or you have set api_use_session_token to api
  session_token, 
  lang: 'en',
  action: [
    'photo_id_front', // request photo ID picture
    'video_selfie_blank' // request passive liveness video
  ],
  meta: { 
    // an ID of user undergoing the check
    // add for easier conversion calculation
    'end_user_id': '<user_or_lead_id>',
    // Your unique identifier that you can use later to find this folder in Oz API 
    // Optional, yet recommended
    'transaction_id': '<your_transaction_id>',
    // You can add iin if you plan to group transactions by the person identifier 
    'iin': '<your_client_iin>',
    // Other meta data
    'meta_key': 'meta_value',
  },
  on_error: function (result) {
  // error details
  console.error('on_error', result);
  },
  on_complete: function (result) {
    // This callback is invoked when the analysis is complete
    // It is recommended to commence the transaction on your backend, 
    // using transaction_id to find the folder in Oz API and get the results
    console.log('on_complete', result);
  },
  on_capture_complete: function (result) {
    // Handle captured data here if necessary
    console.log('on_capture_complete', result);
  }
});
```

[Call](https://apidoc.ozforensics.com/#tag/Folders/paths/~1api~1folders/get) `GET /api/folders/?meta_data=transaction_id==<your_transaction_id>` to find a folder in Oz API from your backend by your unique identifier.

Read more about [Oz API](https://doc.ozforensics.com/oz-knowledge/guides/developer-guide/api/oz-api).

#### Parameters

{% hint style="danger" %}
Please note: license and token must be added on the backend, except for specific cases.
{% endhint %}

The full list of `OzLiveness.open()` parameters:&#x20;

* `options` – an object with the following settings:
  * `session_token` – a specific token required to use OzCapsula data container.
  * `token` – (optional) the auth token;
  * `license` – an object containing the license data;
  * `licenseUrl` – a string containing the path to the license;\ <sub><mark style="background-color:yellow;">**Warning:**<mark style="background-color:yellow;"></sub> <sub><mark style="background-color:yellow;"> </sub><sub><mark style="background-color:yellow;">The<mark style="background-color:yellow;"></sub> <sub><mark style="background-color:yellow;"> </sub><sub><mark style="background-color:yellow;">`license`<mark style="background-color:yellow;"></sub> <sub><mark style="background-color:yellow;"> </sub><sub><mark style="background-color:yellow;">and<mark style="background-color:yellow;"></sub> <sub><mark style="background-color:yellow;"> </sub><sub><mark style="background-color:yellow;">`licenseUrl`<mark style="background-color:yellow;"></sub> <sub><mark style="background-color:yellow;"> </sub><sub><mark style="background-color:yellow;">parameters override the server-side license, including its expiration date. If you use a server-side license, omit these parameters from<mark style="background-color:yellow;"></sub> <sub><mark style="background-color:yellow;"> </sub><sub><mark style="background-color:yellow;">`OzLiveness.open()`<mark style="background-color:yellow;"></sub><sub><mark style="background-color:yellow;">, otherwise, you might be getting a license error.<mark style="background-color:yellow;"></sub>
  * `lang` – a string containing the identifier of one of the installed language packs;
  * `meta` – an object with names of meta fields in keys and their string values in values. [Metadata](https://doc.ozforensics.com/oz-knowledge/guides/developer-guide/api/oz-api/metadata) is transferred to Oz API and can be used to obtain analysis results or for searching;
  * `params` – an object with identifiers and additional parameters:
    * `extract_best_shot` – `true` or `false`: run the best frame choice in the Quality analysis;
  * `action` – an array of strings with identifiers of actions to be performed.\
    \
    **Available actions:**
    * `photo_id_front` – photo of the ID front side;
    * `photo_id_back` – photo of the ID back side;
    * `video_selfie_left` – turn head to the left;
    * `video_selfie_right` – turn head to the right;
    * `video_selfie_down` – tilt head downwards;
    * `video_selfie_high` – raise head up;
    * `video_selfie_smile` – smile;
    * `video_selfie_eyes` – blink;
    * `video_selfie_scan` – scanning;
    * `video_selfie_blank` – no action, simple selfie;
    * `video_selfie_best` – special action to select the best shot from a video and perform analysis on it instead of the full video.\ <sub><mark style="background-color:red;">On January 1, 2027, the One Shot gesture will become unavailable. Please plan your<mark style="background-color:red;"></sub> [<sub><mark style="background-color:red;">migration<mark style="background-color:red;"></sub>](https://doc.ozforensics.com/oz-knowledge/guides/developer-guide/migration-guides/migration-from-one-shot-gesture)<sub><mark style="background-color:red;">.<mark style="background-color:red;"></sub>
  * `overlay_options` – the document's template displaying options:
    * `show_document_pattern`: `true/false` – `true` by default, displays a template image, if set to `false`, the image is replaced by a rectangular frame;
  * `on_submit` – a callback function (no arguments) that is called after submitting customer data to the server (unavailable for the [`capture` mode](https://doc.ozforensics.com/oz-knowledge/guides/developer-guide/sdk/oz-liveness-websdk/web-plugin/launching-the-plugin/capturing-video-and-description-of-the-on_capture_complete-callback)).
  * `on_capture_complete` – a callback function (with one argument) that is called after the video is captured and retrieves the information on this video. The example of the response is described [here](https://doc.ozforensics.com/oz-knowledge/guides/developer-guide/sdk/oz-liveness-websdk/web-plugin/capturing-video-and-description-of-the-on_capture_complete-callback#2.-implementation).
  * `on_result` – a callback function (with one argument) that is called periodically during the analysis and retrieves an intermediate result (unavailable for the `capture` mode). The result content depends on the Web Adapter `result_mode` [configuration parameter](https://doc.ozforensics.com/oz-knowledge/guides/administrator-guide/web-adapter/configuration-file-settings) and is described [here](https://doc.ozforensics.com/oz-knowledge/guides/developer-guide/sdk/oz-liveness-websdk/web-plugin/launching-the-plugin/description-of-the-on_result-callback).
  * `on_complete` – a callback function (with one argument) that is called after the check is completed and retrieves the analysis result (unavailable for the `capture` mode). The result content depends on the Web Adapter `result_mode` [configuration parameter](https://doc.ozforensics.com/oz-knowledge/guides/administrator-guide/web-adapter/configuration-file-settings) and is described [here](https://doc.ozforensics.com/oz-knowledge/guides/developer-guide/sdk/oz-liveness-websdk/web-plugin/launching-the-plugin/description-of-the-on_complete-callback).
  * `on_error` – a callback function (with one argument) that is called in case of any error happened during video capturing and retrieves the error information: an object with the error code, error message, and telemetry ID for logging.
  * `on_close` – a callback function (no arguments) that is called after the plugin window is closed (whether manually by the user or automatically after the check is completed).
  * `style` – [the customization section](https://doc.ozforensics.com/oz-knowledge/guides/developer-guide/sdk/oz-liveness-websdk/web-plugin/look-and-feel-customization/customization-options-for-older-versions-before-1.0.1).
  * `device_id` – (optional) identifier of camera that is being used.
  * `enable_3d_mask` – enables the 3D mask as the default face capture behavior. This parameter works only if `load_3d_mask` in the Web Adapter [configuration parameters](https://doc.ozforensics.com/oz-knowledge/guides/administrator-guide/web-adapter/configuration-file-settings) is set to `true`; the default value is `false`.\ <sub><mark style="background-color:red;">On January 1, 2027, 3D Mask will become unavailable.<mark style="background-color:red;"></sub>
  * `cameraFacingMode` (since 1.4.0) – the parameter that defines which camera to use; possible values: `user` (front camera), `environment` (rear camera). This parameter only works if the `use_for_liveness` option in the [Web Adapter configuration](https://doc.ozforensics.com/oz-knowledge/guides/administrator-guide/web-adapter/configuration-file-settings) file is undefined. If `use_for_liveness` is set (with any value), `cameraFacingMode` gets overridden and ignored.
  * `disable_adaptive_aspect_ratio` (since 1.5.0) – if `True`, disables the video adaptive aspect ratio, so your video doesn’t automatically adjust to the window aspect ratio. The default value is `False`, and by default, the video adjusts to the closest ratio of 4:3, 3:4, 16:9, or 9:16. Please note: smartphones still require the portrait orientation to work.
  * `get_user_media_timeout` (since 1.5.0) – when Web SDK can’t get access to the user camera, after this timeout it displays a hint on how to solve the problem. The default value is 40000 (ms).
  * if the `getUserMedia()` function hangs, you can manage the SDK behavior using the following parameters (since 1.7.15):
    * `get_user_media_promise_timeout_ms`  – set the timeout (in ms) after which SDK will throw an error or display an instruction. This parameter is an object with the following keys: `"platform_browser"`, `"browser"`, `"platform"`, `"default"`(the priority matches the sequence).&#x20;
    * `get_user_media_promise_timeout_throw_error` – defines whether, after the time period defined in the parameter above, SDK should call an error (if `true`) or display a user instruction (if `false`).