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#include "web.h"
#include "db.h"
#include <leveldb/comparator.h>
#include <iomanip>
static inline std::string make_key(uint64_t timestamp) {
std::stringstream key;
key << "ts-";
key << std::setfill('0') << std::setw(20) << timestamp;
return key.str();
}
void web_handle_api_value(const boost::cmatch &match, struct mg_connection *conn) {
// const struct mg_request_info *request_info = mg_get_request_info(conn);
std::string sensor(match[1].str());
uint64_t timestamp = std::stoul(match[2].str());
char buf[1024];
int count = mg_read(conn, buf, 1024);
std::string value(buf, count);
leveldb::DB *db = getDB(sensor);
if (db == nullptr) {
std::cout << "failed to get db for " << sensor << std::endl;
mg_printf(conn, "HTTP/1.1 500 Internal Error\r\n\r\n");
return;
}
std::cout << "sensor=" << sensor << " key=" << make_key(timestamp) << std::endl;
db->Put(leveldb::WriteOptions(), make_key(timestamp), value);
mg_printf(conn, "HTTP/1.1 200 Value received\r\n\r\n");
}
void web_handle_api_range(const boost::cmatch &match, struct mg_connection *conn) {
static const leveldb::Comparator *cmp = leveldb::BytewiseComparator();
std::string sensor(match[1].str());
uint64_t start = std::stoul(match[2].str());
uint64_t end = std::stoul(match[3].str());
std::string key_start(std::move(make_key(start)));
std::string key_end(std::move(make_key(end)));
leveldb::DB *db = getDB(sensor);
if (db == nullptr) {
mg_printf(conn, "HTTP/1.1 500 Internal Error\r\n\r\n");
return;
}
mg_printf(conn,
"HTTP/1.1 200 Value received\r\n"
"Content-Type: application/json; encoding=UTF-8\r\n"
"\r\n");
std::cout << "sensor=" << sensor << " start=" << start << " end=" << end << std::endl;
std::ostringstream out;
out << "{'sensor':'" << sensor << "', 'error':null, 'data':[";
mg_write(conn, out.str().c_str(), out.str().size());
leveldb::Iterator* it = db->NewIterator(leveldb::ReadOptions());
bool first = true;
std::ostringstream outbuf;
for (it->Seek(key_start);
it->Valid() && cmp->Compare(it->key(), key_end) < 0;
it->Next()) {
const char *key = it->key().data();
size_t key_size = it->key().size();
if (key_size != 20+3) {
std::cerr << "invalid key" << std::endl;
return;
}
unsigned int offset = 3; // "ts-"
// skip zeros in timestamp
while (offset < key_size-1 and *(key+offset) == '0')
offset++;
if (first)
first = false;
else
outbuf << ',';
outbuf << '[';
outbuf.write(key+offset, key_size-offset);
outbuf << ',';
outbuf.write(it->value().data(), it->value().size());
outbuf << ']';
mg_write(conn, outbuf.str().c_str(), outbuf.tellp());
outbuf.seekp(0);
}
mg_printf(conn, "]}\r\n");
delete it;
}
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