dap schema

Download the schema of a table.

This command generates and downloads the schema of a specific table within a specified namespace in JSON format.

Usage

dap [arguments] schema [flags]

Options

--namespace <string> Specifies the data source (namespace). Available options: {canvas, canvas_logs, catalog, new_quizzes}.

--table <string> Specifies the tables whose schemas to fetch. Can be a single table name, a comma separated list of table names or the special all keyword to fetch all tables in the namespace.

--output-directory <string> (default: downloads) Specifies the absolute or relative path to the output directory where the snapshot will be stored.

Global options

--client-id <string> Client ID obtained from the Identity Service. Skip, if DAP_CLIENT_ID environment variable is set.

--client-secret <string> Client Secret obtained from the Identity Service. Skip, if DAP_CLIENT_SECRET environment variable is set.

-h, --help Displays help information for the command.

Output

Schema files are written to the output directory with the naming pattern <table>_schema_version_<N>.json, where N is a table-specific version integer. Nothing is printed to stdout.

downloads/accounts_schema_version_2.json
downloads/enrollment_terms_schema_version_1.json

Each schema file has this top-level structure:

{
    "schema": {
        "$schema": "https://json-schema.org/draft/2020-12/schema",
        "type": "object",
        "properties": {
            "meta": {
                "properties": {
                    "ts": { "type": "string", "format": "date-time" },
                    "action": { "type": "string", "enum": ["U", "D"] }
                },
                "required": ["ts"]
            },
            "key": {
                "properties": { "id": { "type": "integer", "format": "int64" } },
                "required": ["id"]
            },
            "value": {
                "properties": { "...": {} },
                "required": ["created_at", "updated_at", "workflow_state"]
            }
        },
        "required": ["key"]
    },
    "version": 2
}

• meta.action: "U" = upsert (insert or update), "D" = hard delete. Only ts is always required in meta.

• key is always required and contains the primary key field(s).

• value contains the data columns. The required fields vary per table.

• version is an integer that increments when the schema changes.

Error handling

Scenario	Exit code	Error output
Invalid table name	5	ERROR - Operation schema failed. Reason: The table name '<name>' specified in the request is not valid.
Invalid namespace	5	ERROR - The namespace '<name>' specified in the request is not valid.

Examples

Get schema of courses and users tables from the canvas namespace: $ dap schema --namespace canvas --table courses,users

Get schema of all tables from the canvas namespace: $ dap schema --namespace canvas --table all

Get schema to a specific directory: $ dap schema --namespace canvas --table accounts --output-directory ./schemas

Related Resources

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Rate Limits & Policies

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Datasets

Discover the available namespaces and tables.