nuts-foundation/nuts-node

/*
 * Copyright (C) 2022 Nuts community
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 *
 */

package didstore

import (
    "encoding/json"
    "errors"
    "fmt"
    "github.com/nuts-foundation/go-did/did"
    "github.com/nuts-foundation/go-stoabs"
    "github.com/nuts-foundation/nuts-node/crypto/hash"
    "github.com/nuts-foundation/nuts-node/vdr/resolver"
)

func readDocument(tx stoabs.ReadTx, documentHash hash.SHA256Hash) (did.Document, error) {
    var document did.Document
    documentReader := tx.GetShelfReader(documentShelf)
    documentBytes, err := documentReader.Get(stoabs.NewHashKey(documentHash))
    if err != nil && !errors.Is(err, stoabs.ErrKeyNotFound) {
        return document, err
    }
    if len(documentBytes) == 0 {
        return document, resolver.ErrNotFound
    }
    if err := json.Unmarshal(documentBytes, &document); err != nil {
        return document, fmt.Errorf("unmarshal error on document: %w", err)
    }

    return document, nil
}

func readDocumentFromEvent(tx stoabs.ReadTx, e event) (did.Document, error) {
    if e.document != nil {
        return *e.document, nil
    }
    return readDocument(tx, e.PayloadHash)
}

func readMetadata(tx stoabs.ReadTx, ref []byte) (documentMetadata, error) {
    var metadata documentMetadata
    metadataReader := tx.GetShelfReader(metadataShelf)
    metadataBytes, err := metadataReader.Get(stoabs.BytesKey(ref))
    if err != nil && !errors.Is(err, stoabs.ErrKeyNotFound) {
        return metadata, err
    }
    if len(metadataBytes) == 0 {
        return metadata, errors.New("documentMetadata not found")
    }
    if err := json.Unmarshal(metadataBytes, &metadata); err != nil {
        return metadata, fmt.Errorf("unmarshal error on documentMetadata: %w", err)
    }

    return metadata, nil
}

func readEventList(tx stoabs.ReadTx, id did.DID) (eventList, error) {
    el := eventList{}
    eventReader := tx.GetShelfReader(eventShelf)
    eventListBytes, err := eventReader.Get(stoabs.BytesKey(id.String()))
    if err != nil && !errors.Is(err, stoabs.ErrKeyNotFound) {
        return el, err
    }
    if len(eventListBytes) == 0 {
        // New DID Document to be created, no existing events to be found.
        return el, nil
    }

    err = json.Unmarshal(eventListBytes, &el)
    if err != nil {
        return el, fmt.Errorf("unmarshal error on eventList: %w", err)
    }
    return el, nil
}