TreeDB Helpers

Utilities for interacting with the Yuneta TreeDB — the schema-driven graph database built on top of timeranger2. See the Timeranger2 API and the TreeDB crash course for the underlying semantics.

Available helpers¶

import {
    treedb_hook_data_size,
    treedb_decoder_fkey,
    treedb_encoder_fkey,
    treedb_decoder_hook,
    treedb_get_field_desc,
    template_get_field_desc,
    create_template_record,
} from "@yuneta/gobj-js";

treedb_hook_data_size(value)¶

Counts the items that a hook field references.

treedb_decoder_fkey(col, fkey)¶

Reads a foreign-key reference, and gives its topic, its identifier and its hook.

treedb_encoder_fkey(col, fkey)¶

Builds the canonical form of a foreign-key reference, "topic^id^hook".

treedb_decoder_hook(col, hook)¶

Reads a hook reference.

treedb_get_field_desc(col)¶

Builds the descriptor of a field from the definition of a column.

template_get_field_desc(key, value)¶

Builds the descriptor of a field from one entry of a template.

create_template_record(template, kw)¶

Builds a new record from the definition of a template.

Fkey format¶

TreeDB references children from parents via hooks (in-memory only) and children point back to parents via fkeys (persisted). An fkey value is a string with three ^-separated fields:

topic^parent_id^hook_name

For example, a user record under the administration department can have:

departments^administration^users

meaning “my parent is in topic departments, with primary key administration, and I belong to its users hook.”

The treedb_encoder_fkey / treedb_decoder_fkey helpers hide this encoding so application code rarely has to look at the raw string.