Vấn đề tôi cần giải quyết là lưu trữ các hợp đồng có chứa một vài trường (địa chỉ, sách, num_of_days, vayer_addr, blk_data), blk_data là danh sách giao dịch (số khối và địa chỉ giao dịch). Câu hỏi và câu trả lời này đã giúp tôi. Tôi muốn chia sẻ mã của tôi như dưới đây. Hi vọng điêu nay co ich.
- Định nghĩa lược đồ. Xem blk_data.
var ContractSchema = new Schema(
{
address: {type: String, required: true, max: 100}, //contract address
// book_id: {type: String, required: true, max: 100}, //book id in the book collection
book: { type: Schema.ObjectId, ref: 'clc_books', required: true }, // Reference to the associated book.
num_of_days: {type: Number, required: true, min: 1},
borrower_addr: {type: String, required: true, max: 100},
// status: {type: String, enum: ['available', 'Created', 'Locked', 'Inactive'], default:'Created'},
blk_data: [{
tx_addr: {type: String, max: 100}, // to do: change to a list
block_number: {type: String, max: 100}, // to do: change to a list
}]
}
);
- Tạo bản ghi cho bộ sưu tập trong MongoDB. Xem blk_data.
// Post submit a smart contract proposal to borrowing a specific book.
exports.ctr_contract_propose_post = [
// Validate fields
body('book_id', 'book_id must not be empty.').isLength({ min: 1 }).trim(),
body('req_addr', 'req_addr must not be empty.').isLength({ min: 1 }).trim(),
body('new_contract_addr', 'contract_addr must not be empty.').isLength({ min: 1 }).trim(),
body('tx_addr', 'tx_addr must not be empty.').isLength({ min: 1 }).trim(),
body('block_number', 'block_number must not be empty.').isLength({ min: 1 }).trim(),
body('num_of_days', 'num_of_days must not be empty.').isLength({ min: 1 }).trim(),
// Sanitize fields.
sanitizeBody('*').escape(),
// Process request after validation and sanitization.
(req, res, next) => {
// Extract the validation errors from a request.
const errors = validationResult(req);
if (!errors.isEmpty()) {
// There are errors. Render form again with sanitized values/error messages.
res.status(400).send({ errors: errors.array() });
return;
}
// Create a Book object with escaped/trimmed data and old id.
var book_fields =
{
_id: req.body.book_id, // This is required, or a new ID will be assigned!
cur_contract: req.body.new_contract_addr,
status: 'await_approval'
};
async.parallel({
//call the function get book model
books: function(callback) {
Book.findByIdAndUpdate(req.body.book_id, book_fields, {}).exec(callback);
},
}, function(error, results) {
if (error) {
res.status(400).send({ errors: errors.array() });
return;
}
if (results.books.isNew) {
// res.render('pg_error', {
// title: 'Proposing a smart contract to borrow the book',
// c: errors.array()
// });
res.status(400).send({ errors: errors.array() });
return;
}
var contract = new Contract(
{
address: req.body.new_contract_addr,
book: req.body.book_id,
num_of_days: req.body.num_of_days,
borrower_addr: req.body.req_addr
});
var blk_data = {
tx_addr: req.body.tx_addr,
block_number: req.body.block_number
};
contract.blk_data.push(blk_data);
// Data from form is valid. Save book.
contract.save(function (err) {
if (err) { return next(err); }
// Successful - redirect to new book record.
resObj = {
"res": contract.url
};
res.status(200).send(JSON.stringify(resObj));
// res.redirect();
});
});
},
];
- Cập nhật bản ghi. Xem blk_data.
// Post lender accept borrow proposal.
exports.ctr_contract_propose_accept_post = [
// Validate fields
body('book_id', 'book_id must not be empty.').isLength({ min: 1 }).trim(),
body('contract_id', 'book_id must not be empty.').isLength({ min: 1 }).trim(),
body('tx_addr', 'tx_addr must not be empty.').isLength({ min: 1 }).trim(),
body('block_number', 'block_number must not be empty.').isLength({ min: 1 }).trim(),
// Sanitize fields.
sanitizeBody('*').escape(),
// Process request after validation and sanitization.
(req, res, next) => {
// Extract the validation errors from a request.
const errors = validationResult(req);
if (!errors.isEmpty()) {
// There are errors. Render form again with sanitized values/error messages.
res.status(400).send({ errors: errors.array() });
return;
}
// Create a Book object with escaped/trimmed data
var book_fields =
{
_id: req.body.book_id, // This is required, or a new ID will be assigned!
status: 'on_loan'
};
// Create a contract object with escaped/trimmed data
var contract_fields = {
$push: {
blk_data: {
tx_addr: req.body.tx_addr,
block_number: req.body.block_number
}
}
};
async.parallel({
//call the function get book model
book: function(callback) {
Book.findByIdAndUpdate(req.body.book_id, book_fields, {}).exec(callback);
},
contract: function(callback) {
Contract.findByIdAndUpdate(req.body.contract_id, contract_fields, {}).exec(callback);
},
}, function(error, results) {
if (error) {
res.status(400).send({ errors: errors.array() });
return;
}
if ((results.book.isNew) || (results.contract.isNew)) {
res.status(400).send({ errors: errors.array() });
return;
}
var resObj = {
"res": results.contract.url
};
res.status(200).send(JSON.stringify(resObj));
});
},
];
trk.latvàtrk.lngtrong html sẽ không hoạt động.