Crate jlens_schema 

jlens-schema

Structural metadata for JSON documents, and the JSONata language service built on it.

• Inference. Schema::infer derives a Schema from sample documents. It records types, required and optional fields, array items, number ranges, string formats, small enumerations and examples.
• Configuration. Schema::apply_overrides adds descriptions, labels, allowed values and hidden fields. Schemas convert to and from JSON Schema 2020-12 (Schema::to_json_schema, Schema::from_json_schema), so they can be versioned and edited by hand.
• Language service. LanguageService offers completion, diagnostics (including references to fields that the schema does not have), hover and signature help for JSONata expressions. It types each part of an expression against the schema, following the evaluator’s rules for paths, filters and variables.

use jlens_schema::{LanguageService, Schema};
use serde_json::json;

let schema = Schema::infer(&[json!({
    "customer": {"login": "123", "name": "XYZ"},
    "items": [{"code": "1", "type": "apparel", "unitPrice": 10.0, "quantity": 2}]
})]);
let service = LanguageService::new(Some(schema));

// Fields of the items, inside a filter:
let text = "items[ty";
let labels: Vec<_> = service.complete(text, text.len()).items.into_iter()
    .map(|i| i.label).collect();
assert_eq!(labels, ["type", "$type"]); // fields first, then matching functions

// A misspelt field is reported:
let warnings = service.diagnostics("customer.Login");
assert_eq!(warnings[0].code, "W0201");
assert!(warnings[0].message.contains("did you mean `login`"));

Structs

CompletionItem

One completion suggestion.

Completions

Completion results.

Field

A field of an object shape.

FunctionDecl

A function the host application provides (a jlens_core::HostFunction), declared to the language service so that it is completed and documented like a built-in function.

Hover

Hover information.

LanguageService

Completion, diagnostics, hover and signature help for expressions over a schema.

Override

Settings applied to the shape at one path (see Schema::apply_overrides).

Schema

Structural metadata about a family of JSON documents.

Shape

The structure of the values found at one place in the documents.

SignatureHelp

Help for the function call around the cursor.

Enums

CompletionKind

What a completion item inserts.

JsonType

JSON types, as in JSON Schema (integer is a number without a fractional part).