Edifact.Core 1.0.0-preview.4

Edifact.Core

The layer below any directory: an ISO 9735 tokenizer and writer, delimiter and character repertoire handling, and the finding, severity and EDI path types every other Edifact.* package reports through.

This is the only package here that needs no directory data at all. It answers questions about characters — where the delimiters are, which of them were released, where one segment ends and the next begins — and it answers them for a file nobody has a directory for. It does not know what INVOIC is and cannot tell you whether a segment belongs where it sits; that is Edifact.Structure and Edifact.Validation.

Install

dotnet add package Edifact.Core --prerelease

net8.0 and net10.0, no external dependencies.

Use it

using Edifact.Core.Diagnostics;
using Edifact.Core.Syntax;

var text = File.ReadAllText("interchange.edi");

// Nothing on this path throws. A truncated transmission, a stray release character, an
// unterminated final segment — all of it comes back as segments plus findings.
var result = EdifactTokenizer.Tokenize(text);

foreach (var segment in result.Segments)
{
    // Value(element, component); both are zero-based, so this is NAD's first qualifier.
    Console.WriteLine($"{segment.Tag}  {segment.Value(0)}  (segment #{segment.Index})");
}

foreach (var finding in result.Findings)
{
    // FATAL SYNTAX.UNTERMINATED at 42:18: The interchange ends inside a segment.
    Console.WriteLine(finding);
}

Console.WriteLine(result.Syntax.Delimiters.ToUna());   // UNA:+.? '
Console.WriteLine(result.Syntax.HadUna);               // whether it was declared or assumed

The property this package exists to hold

Reading an interchange and writing it back gives the same characters — the delimiters it arrived with, the release characters somebody used redundantly, the line ending, the trailing newline, and the fragment of a segment a truncated transmission ended in the middle of:

var reproduced = EdifactWriter.Write(result) == text;   // true

That is the correctness asset the whole library is built on, because it is the only check that fails when something is quietly dropped rather than misunderstood. EdifactWriter.Write also takes any IEnumerable<RawSegment> with an InterchangeSyntax, which is how a composed message — one that was never read from a file — gets written.

Findings

Every diagnostic in the library is a Finding: a Severity, a stable dotted RuleId such as SYNTAX.UNTERMINATED, an EdiPath, a SourceSpan carrying both the text offset and the 1-based segment, element and component positions, a sentence written for a person, and a Provenance saying which authority the broken rule came from. Severity is ordered — Information, Warning, Error, Fatal — so finding.Severity >= Severity.Error filters the way it reads.

An unknown code value is a Warning, not an Error. Published code lists are advisory on their own and interchange agreements extend them routinely, so rejecting on one would reject valid traffic.

Where this sits

Edifact.Core references nothing, which is what lets a file nobody has a directory for still be read and shown to somebody. Everything else is layered over it: Edifact.Schema (what a release says), Edifact.Structure (matching a segment table), Edifact.Validation (the usual entry point), Edifact.Projection, Edifact.Overlays, Edifact.Untdid and Edifact.Acknowledgement. The edifact CLI is the same code as a tool.

Full documentation: https://github.com/WimSuenens/EDIFACT.

Licence

Apache-2.0. See the NOTICE in this package for what the wider project is derived from and under what terms.