gedcom

Go package to parse and produce GEDCOM files.

Purpose

The gedcom package provides tools for working with GEDCOM files in Go. GEDCOM (Genealogical Data Communication) is a standard format used for exchanging genealogical data between software applications. This package includes functionality for both parsing existing GEDCOM files and generating new ones.

The package includes a streaming decoder for reading GEDCOM files and an encoder for creating GEDCOM files from Go structs.

Usage

The package provides a Decoder with a single Decode method that returns a Gedcom struct. Use the NewDecoder method to create a new decoder.

This example shows how to parse a GEDCOM file and list all the individuals. In this example the entire input file is read into memory, but the decoder is streaming so it should be able to deal with very large files: just pass an appropriate Reader.

package main

import (
	"bytes"
	"github.com/iand/gedcom"
	"io/ioutil"
)

func main() {
	data, _ := ioutil.ReadFile("testdata/kennedy.ged")

	d := gedcom.NewDecoder(bytes.NewReader(data))

	g, _ := d.Decode()

	for _, rec := range g.Individual {
		if len(rec.Name) > 0 {
			println(rec.Name[0].Name)
		}			
	}
}

The structures produced by the Decoder are in types.go and correspond roughly 1:1 to the structures in the GEDCOM specification.

Using the Encoder

In addition to decoding GEDCOM files, this package also provides an Encoder for generating GEDCOM files from the structs in types.go. You can create an encoder using the NewEncoder method, which writes to an io.Writer.

By default the encoder produces GEDCOM 5.5 output. Use SetVersion to produce GEDCOM 7.0 output:

enc := gedcom.NewEncoder(w)
enc.SetVersion(gedcom.Gedcom70)

To see a full example of how to use the encoder, refer to encoder_example.go.

Compatibility

GEDCOM 5.5/5.5.1

The decoder supports the core GEDCOM 5.5/5.5.1 record types: HEAD, INDI, FAM, SOUR, REPO, OBJE, SUBM, SUBN, and TRLR. Within these records, the commonly used tags are handled, covering the vast majority of real-world GEDCOM files. Tags that are not recognized by the decoder are preserved as UserDefinedTag values, so no data is silently discarded. The encoder can round-trip all decoded data, with the exception of Submitter references on individual records.

GEDCOM 7.0

The decoder reads GEDCOM 7.0 files transparently, including files with a UTF-8 BOM. The following GEDCOM 7.0 tags are supported in addition to the 5.5/5.5.1 tags:

Tag	Description	Context
SNOTE	Shared note record and references	Top-level record; references in individuals, families, sources, repositories, media, submitters, events, names
SCHMA	Schema for extension tag definitions	Header
TAG	Extension tag-to-URI mapping	Schema
EXID	External identifier	Individuals, families, sources, repositories, media, submitters
UID	Unique identifier	Individuals, families, sources, repositories, media, submitters
CREA	Record creation date	Individuals, families, sources, repositories, media, submitters, shared notes
SDATE	Sort date for ordering events	Events
NO	Non-event (assertion that an event did not occur)	Individuals, families
CROP	Image crop region	Media file
TRAN	Translation of text	Shared notes, notes, names, places
MIME	MIME type of text content	Shared notes, notes
LANG	BCP 47 language tag	Shared notes, notes, places
RESN	Restriction notice	Individuals, families, sources, names
ROLE	Role in an association (with PHRASE sub-tag)	Associations
INIL	Initiatory (LDS)	Individual events
BAPL	Baptism (LDS)	Individual events
CONL	Confirmation (LDS)	Individual events
ENDL	Endowment (LDS)	Individual events
SLGC	Sealing to parents (LDS)	Individual events
SLGS	Sealing to spouse (LDS)	Family events
FACT	Fact	Family events
AGE	Age at event	Events

The encoder can produce GEDCOM 7.0 output via SetVersion(Gedcom70). In this mode it writes a UTF-8 BOM, omits the CHAR and GEDC.FORM tags, sets GEDC.VERS to 7.0, and writes long text lines without CONC splitting.

Ancestry

Ancestry is a major producer of GEDCOM files. The decoder includes workarounds for known issues in Ancestry exports:

• Malformed NOTE values: Ancestry sometimes produces NOTE tags with embedded newlines in the value (i.e. line breaks that are not preceded by a CONT tag). The scanner detects and recovers from this by treating the continuation as part of the NOTE value.
• Non-standard PUBL sub-tags: Ancestry exports may include DATE and PLAC tags nested under the PUBL (publication facts) tag, which is not part of the GEDCOM specification. The decoder incorporates these values into the publication facts string rather than discarding them.

Installation

Simply run

Run the following in the directory containing your project's go.mod file:

go get github.com/iand/gedcom@latest

Documentation is at https://pkg.go.dev/github.com/iand/gedcom

Authors

• Ian Davis

Contributors

Contributing

• Do submit your changes as a pull request
• Do your best to adhere to the existing coding conventions and idioms.
• Do run go fmt on the code before committing
• Do feel free to add yourself to the CREDITS file and the corresponding Contributors list in the README.md. Alphabetical order applies.
• Don't touch the AUTHORS file. An existing author will add you if your contributions are significant enough.
• Do note that in order for any non-trivial changes to be merged (as a rule of thumb, additions larger than about 15 lines of code), an explicit Public Domain Dedication needs to be on record from you. Please include a copy of the statement found in the WAIVER file with your pull request

License

This is free and unencumbered software released into the public domain. For more information, see http://unlicense.org/ or the accompanying UNLICENSE file.