function* uploadImage({
payload: { file, dataUrl, filename = 'image.txt', progress },
}) {
const _progress = progress;
progress = msg => {
// console.log('Upload image progress', msg)
_progress(msg);
};
const stateUser = yield select(state => state.user);
const username = stateUser.getIn(['current', 'username']);
const d = stateUser.getIn(['current', 'private_keys', 'posting_private']);
if (!username) {
progress({ error: 'Please login first.' });
return;
}
if (!d) {
progress({ error: 'Login with your posting key' });
return;
}
if (!file && !dataUrl) {
console.error('uploadImage required: file or dataUrl');
return;
}
let data, dataBs64;
if (file) {
// drag and drop
const reader = new FileReader();
data = yield new Promise(resolve => {
reader.addEventListener('load', () => {
const result = new Buffer(reader.result, 'binary');
resolve(result);
});
reader.readAsBinaryString(file);
});
} else {
// recover from preview
const commaIdx = dataUrl.indexOf(',');
dataBs64 = dataUrl.substring(commaIdx + 1);
data = new Buffer(dataBs64, 'base64');
}
// The challenge needs to be prefixed with a constant (both on the server and checked on the client) to make sure the server can't easily make the client sign a transaction doing something else.
const prefix = new Buffer('ImageSigningChallenge');
const bufSha = hash.sha256(Buffer.concat([prefix, data]));
const formData = new FormData();
if (file) {
formData.append('file', file);
} else {
// formData.append('file', file, filename) <- Failed to add filename=xxx to Content-Disposition
// Can't easily make this look like a file so this relies on the server supporting: filename and filebinary
formData.append('filename', filename);
formData.append('filebase64', dataBs64);
}
const sig = Signature.signBufferSha256(bufSha, d);
const postUrl = `${$STM_Config.upload_image}/${username}/${sig.toHex()}`;
const xhr = new XMLHttpRequest();
xhr.open('POST', postUrl);
xhr.onload = function() {
console.log(xhr.status, xhr.responseText);
const res = JSON.parse(xhr.responseText);
const { error } = res;
if (error) {
progress({ error: 'Error: ' + error });
return;
}
const { url } = res;
progress({ url });
};
xhr.onerror = function(error) {
console.error(filename, error);
progress({ error: 'Unable to contact the server.' });
};
xhr.upload.onprogress = function(event) {
if (event.lengthComputable) {
const percent = Math.round(event.loaded / event.total * 100);
progress({ message: `Uploading ${percent}%` });
// console.log('Upload', percent)
}
};
xhr.send(formData);
}
const sign = (role, d) => {
if (!d) return;
const sig = Signature.signBufferSha256(bufSha, d);
signatures[role] = sig.toHex();
};