Interaction with ScaleTrade Servers

A developer guide to the internal interaction between ScaleTrade trade servers and Linux-based report modules.

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Overview

This section explains how the ScaleTrade trade server communicates with report modules.
The Report API enables servers to detect, load, initialize, and execute report plugins dynamically at runtime.

Environment Notice

Unlike its predecessors, ScaleTrade operates entirely under Linux, and report plugins are implemented as shared libraries (.so), not DLLs.

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Compatibility

Each server can work only with modules matching its architecture bitness.
That means: - A 64-bit ScaleTrade server will load only 64-bit modules. - A 32-bit server will load only 32-bit modules.

Developers should therefore provide both versions when distributing plugins.

Recommended Naming Convention

trade_summary.so        → 32-bit build
trade_summary64.so      → 64-bit build

Report plugins are executed exclusively on trade servers, not access or backup nodes.

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Module Initialization

When the server starts, it automatically scans the /opt/ScaleTrade/reports/ directory, including subdirectories, to detect report modules.

Initialization Process

flowchart TD
    A[ScaleTrade Server Startup] --> B[Scan /opt/ScaleTrade/reports/]
    B --> C[Locate .so files]
    C --> D[Load each shared library]
    D --> E[Call ITReportAbout()]
    E --> F[Retrieve ReportInfo structure]
    F --> G[Verify API version compatibility]
    G --> H{Supported?}
    H -->|Yes| I[Register report module]
    H -->|No| J[Skip and log incompatibility]

1. The server loads each shared object file (.so).
2. It calls the ITReportAbout() function, which returns a ReportInfo structure describing the module (metadata, name, version, capabilities).
3. If the module doesn’t export ITReportAbout(), it’s skipped and logged as a non-report binary.
4. Each plugin can expose up to 1024 reports within a single .so.
5. The server enumerates these reports sequentially until it receives RET_ERR_NOTFOUND or RET_ERROR_NOTIMPLEMENTED.

Version Compatibility

The Report API version declared in ReportInfo must match the version supported by the ScaleTrade server.
Incompatible modules are ignored and logged with a warning.
Rebuild your plugin using the latest ScaleTrade Report API SDK to restore compatibility.

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Configuration Loading

After initialization, the server reads all report configurations stored in the system.
Only those report modules defined in administrator configurations are activated.

Each report module can be instantiated multiple times with different configuration parameters.

Multiple Configurations

For example, a single report module performance_report.so can be run: - once for daily trade summaries, and
- once for monthly PnL analytics.

This is configured through the Administrator Terminal or directly via /etc/ScaleTrade/config/reports.conf.

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Report Request Handling

Reports are generated on demand when requested by a manager terminal or automation script.

When a request arrives, the server: 1. Creates a report context via the ITReportCreate() function.
2. Passes an API interface pointer (IReportAPI* api) to allow data access.
3. Calls the context’s methods defined by the IReportContext interface to generate the output.

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IReportContext Interface

The IReportContext interface defines the lifecycle of a report and includes the following core methods:

Method	Description
Release()	Deletes the created report object. Unlike reference-counted systems, ScaleTrade removes the object immediately without decrementing a counter.
Generate()	Invoked by the server to start report generation. The method receives a pointer to the active IReportAPI interface, which the plugin uses to query data and generate output.

Interface Workflow

sequenceDiagram
    participant Server
    participant Plugin
    participant API

    Server->>Plugin: ITReportCreate()
    Plugin-->>Server: Return IReportContext
    Server->>Plugin: Generate(API*)
    Plugin->>API: Query data (users, trades, accounts)
    API-->>Plugin: Data stream
    Plugin-->>Server: Report ready
    Server->>Plugin: Release()

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Summary

• ScaleTrade servers load report modules dynamically from /opt/ScaleTrade/reports/.
• Plugins must match server architecture and Report API version.
• Modules are configured by admins and executed upon request.
• Reports are generated through the IReportContext interface using the provided IReportAPI.
• All components operate under Linux, ensuring performance and reliability.

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