Services interaction

There are separate databases specified for each service in the images below. This is done for illustration purposes.

It is not required to launch several similar databases for each service. You can launch a single database instance (e. g., PostgreSQL) and use it to store data for all the LP services. Each service will have its own table in this database.

See "General concepts" for details about the databases used by LP services.

API service provides a RESTful interface for faces and bodies detection, extraction and matching procedures.

Requests are sent to LP via HTTP. A common case is when an external service sends requests to LP, receives results and processes the results according to business needs.

You can find all the information about general requests to the API service in the API reference manual. The name of the section describing the corresponding request is given in brackets.

Services interaction

Some services can be disabled (see "General concepts").

API receives requests, processes them and checks user authorization using a request to the Accounts service (A0). The Accounts service checks if the user's credentials exist in the Accounts database (Acc1). If the user data is not found in the database, then an authorization error is issued. If the data is found, then the corresponding information is sent to the API service, where it passes the original requests to other services:

• The requests for face detection, face parameters estimation and samples creation (Samples > Detect faces) are sent to the Handlers (A1);
• The requests for temporary attributes creation (Attributes > Extract attributes) are sent to the Handlers service (A1);
• The requests for descriptors matching (Matcher > Matching) can be sent to the Python Matcher service (A6).

API sends requests to Faces for new faces creation, as well as lists creation and managing (Faces section) (A2).

The API service receives information about the current license terms from the Licenses service (A3) using middleware.

The API service sends samples received from external services to the Image Store service (Samples > Save sample) (A5).

Handlers processes face/body detection and attributes creation requests. It estimates face attributes and face/body parameters.

Handlers processes detection request from API (A1) and sends resulting samples to the Image Store service (H1).

Handlers processes attributes creation request from API (H1), requests existing samples from the Image Store service (H1) and sends the created temporary attributes to the Faces service that stores them in the Redis database (F1).

The Handlers service creates new handlers (Handlers > Create handler) and stores them in the Handlers database (H3).

The request for a new event creation (Events > Generate events) is received by API, sent to Handlers (H1) and processed according to the Handler, which ID is specified in the request.

Image Store receives samples from the Handlers service and stores them on SSD or in the S3 database and provides access to them (Im1).

Licenses. The Licenses service receives information about the number of created faces with attributes from the Faces database (Li1).

Faces is responsible for interaction with Faces database, which stores: faces, descriptors for faces, and lists (F2). It provides access to the stored data for API, Python Matcher, and Tasks services.

Faces also stores the created temporary attributes in the Redis database (F1).

Events  service stores and provides information about events (the Events section). After an event is created, the Events service receives the created event from the Handlers service (H4) and stores it in the Events database (Ev2).

The Events service usage can be enabled/disabled in the API service configuration file.

Python Matcher can receive matching requests directly from the API service (A6). Python Matcher sends matching requests to the Faces database (M3) or Events database (M1). The databases matches descriptors and sends results back to the API service.

Python Matcher can also receive the temporary attributes required for matching from the Redis database (M2).

It is possible to additionally use the Python Matcher Proxy service, which can redirect requests to Python Matcher or matching plugins. Matching plugins can significantly speed up the matching requests execution (see the "Matching plugins" section). This service is not shown in the diagram, but has the same communication lines as the Python Matcher service.

Admin. A user can manage accounts and perform other actions via the user interface of the Admin service (Adm1). The corresponding requests are sent to the Admin service (Adm2).

You can find all the information about requests in the Admin service reference manual.

All information about user accounts is stored in the Accounts database (Acc1).

The Admin service sends requests to Tasks service (Adm4). These tasks are performed for LP databases in general, not for a single account ID.

The Admin service receives information about the current license terms from the Licenses service (Adm5).

The Admin service checks the current number of created faces with linked attributes in the Faces database (Adm6) and calculates the percentage of the database of fullness.

The Admin service also makes requests to all LP services, receiving system information (see "/luna_sys_info" request). This interaction is not shown in the diagram.

Sender. All generated events are received by the Redis DB from the Handlers service (H6). External third-party party software subscribes to receive events according to the specified filters (Se2). Sender service checks Redis channel, receives the required information and sends it to external software (Se1).

Sender service usage is enabled/disabled in the API service configuration file.

Configurator. LP services receive configuration parameters from the Configurator service (Con1). A user can manage configurations in Configurator by means of the graphical user interface (Con2). The changes are sent to Configurator (Con3). All the changes in configuration files are saved in Configurator DB (Con4).

Configurator is utilized for each Luna service by default.

Tasks. Tasks service receives requests from API service (A8). Then Tasks creates and stores a task in the Tasks database (T1). Then Tasks sends subtasks to its workers (T2), which also have access to the Tasks (T3) database.

Tasks service receives data from Faces service for clustering, linker, and additional extraction tasks (T4).

Tasks service receives data from Events service for clustering and linker tasks (T9, T0).

Tasks service usage is enabled/disabled in the API service configuration file.

The interaction of Tasks workers with other services depends on the task type.

Tasks workers receive data from Faces service for every processed task (T5).

Tasks workers send a request to Python Matcher (T7) for clustering, cross-matching and ROC creation tasks.

Tasks workers store all the reports in the storage of Image Store (T8). Tasks workers also store and receive clusters from Image Store.

Tasks workers send the request for additional extraction task to the Handler service (T6).

Monitoring. Monitoring system receives requests and errors from each service (Mon1). This data stores in the Influx database (Mon2). Then the monitoring data is sent to Grafana to visualize the monitoring data (Mon3). You can find more information about monitoring in the "Monitoring" section.

This diagram does not contain the architecture of the Backport 3 and Backport 4 services. See the detailed architecture of the Backport 3 service in "Backport 3 architecture" section and the Backport 4 service in "Backport 4 architecture" section.