2017-06-01 10:24:20 +03:00

1061 lines
29 KiB
C

/*
* Copyright (c) 2016 MariaDB Corporation Ab
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file and at www.mariadb.com/bsl11.
*
* Change Date: 2020-01-01
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2 or later of the General
* Public License.
*/
/**
* @file avro_client.c - contains code for the AVRO router to client communication
*
* @verbatim
* Revision History
*
* Date Who Description
* 10/03/2016 Massimiliano Pinto Initial implementation
* 11/03/2016 Massimiliano Pinto Addition of JSON output
*
* @endverbatim
*/
#include "avrorouter.h"
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <maxscale/service.h>
#include <maxscale/server.h>
#include <maxscale/router.h>
#include <maxscale/atomic.h>
#include <maxscale/spinlock.h>
#include <maxscale/dcb.h>
#include <maxscale/spinlock.h>
#include <maxscale/log_manager.h>
#include <maxscale/version.h>
#include <maxavro.h>
#include <maxscale/alloc.h>
extern char *blr_extract_column(GWBUF *buf, int col);
extern uint32_t extract_field(uint8_t *src, int bits);
/* AVRO */
static int avro_client_do_registration(AVRO_INSTANCE *, AVRO_CLIENT *, GWBUF *);
int avro_client_callback(DCB *dcb, DCB_REASON reason, void *data);
static void avro_client_process_command(AVRO_INSTANCE *router, AVRO_CLIENT *client, GWBUF *queue);
static bool avro_client_stream_data(AVRO_CLIENT *client);
void avro_notify_client(AVRO_CLIENT *client);
void poll_fake_write_event(DCB *dcb);
GWBUF* read_avro_json_schema(const char *avrofile, const char* dir);
GWBUF* read_avro_binary_schema(const char *avrofile, const char* dir);
const char* get_avrofile_name(const char *file_ptr, int data_len, char *dest);
/**
* Process a request packet from the slave server.
*
* @param router The router instance this defines the master for this replication chain
* @param client The client specific data
* @param queue The incoming request packet
* @return 1 on success, 0 on error or failure
*/
int
avro_client_handle_request(AVRO_INSTANCE *router, AVRO_CLIENT *client, GWBUF *queue)
{
int rval = 1;
switch (client->state)
{
case AVRO_CLIENT_ERRORED:
/* force disconnection */
return 0;
break;
case AVRO_CLIENT_UNREGISTERED:
if (avro_client_do_registration(router, client, queue) == 0)
{
client->state = AVRO_CLIENT_ERRORED;
dcb_printf(client->dcb, "ERR, code 12, msg: Registration failed\n");
/* force disconnection */
dcb_close(client->dcb);
rval = 0;
}
else
{
/* Send OK ack to client */
dcb_printf(client->dcb, "OK\n");
client->state = AVRO_CLIENT_REGISTERED;
MXS_INFO("%s: Client [%s] has completed REGISTRATION action",
client->dcb->service->name,
client->dcb->remote != NULL ? client->dcb->remote : "");
}
break;
case AVRO_CLIENT_REGISTERED:
case AVRO_CLIENT_REQUEST_DATA:
if (client->state == AVRO_CLIENT_REGISTERED)
{
client->state = AVRO_CLIENT_REQUEST_DATA;
}
/* Process command from client */
avro_client_process_command(router, client, queue);
break;
default:
client->state = AVRO_CLIENT_ERRORED;
rval = 0;
break;
}
gwbuf_free(queue);
return rval;
}
/**
* Handle the REGISTRATION command
*
* @param dcb DCB with allocateid protocol
* @param data GWBUF with registration message
* @return 1 for successful registration 0 otherwise
*
*/
static int
avro_client_do_registration(AVRO_INSTANCE *router, AVRO_CLIENT *client, GWBUF *data)
{
const char reg_uuid[] = "REGISTER UUID=";
const int reg_uuid_len = strlen(reg_uuid);
int data_len = GWBUF_LENGTH(data) - reg_uuid_len;
char *request = (char*)GWBUF_DATA(data);
int ret = 0;
if (strstr(request, reg_uuid) != NULL)
{
char *sep_ptr;
int uuid_len = (data_len > CDC_UUID_LEN) ? CDC_UUID_LEN : data_len;
/* 36 +1 */
char uuid[uuid_len + 1];
memcpy(uuid, request + reg_uuid_len, uuid_len);
uuid[uuid_len] = '\0';
if ((sep_ptr = strchr(uuid, ',')) != NULL)
{
*sep_ptr = '\0';
}
if ((sep_ptr = strchr(uuid + strlen(uuid), ' ')) != NULL)
{
*sep_ptr = '\0';
}
if ((sep_ptr = strchr(uuid, ' ')) != NULL)
{
*sep_ptr = '\0';
}
if (strlen(uuid) < uuid_len)
{
data_len -= (uuid_len - strlen(uuid));
}
uuid_len = strlen(uuid);
client->uuid = MXS_STRDUP_A(uuid);
if (data_len > 0)
{
/* Check for CDC request type */
char *tmp_ptr = strstr(request + sizeof(reg_uuid) + uuid_len, "TYPE=");
if (tmp_ptr)
{
if (memcmp(tmp_ptr + 5, "AVRO", 4) == 0)
{
ret = 1;
client->state = AVRO_CLIENT_REGISTERED;
client->format = AVRO_FORMAT_AVRO;
}
else if (memcmp(tmp_ptr + 5, "JSON", 4) == 0)
{
ret = 1;
client->state = AVRO_CLIENT_REGISTERED;
client->format = AVRO_FORMAT_JSON;
}
else
{
fprintf(stderr, "Registration TYPE not supported, only AVRO\n");
}
}
else
{
fprintf(stderr, "TYPE not found in Registration\n");
}
}
else
{
fprintf(stderr, "Registration data_len = 0\n");
}
}
return ret;
}
/**
* Extract the GTID the client requested
* @param gtid
* @param start
* @param end
*/
void extract_gtid_request(gtid_pos_t *gtid, const char *start, int len)
{
const char *ptr = start;
int read = 0;
while (ptr < start + len)
{
if (!isdigit(*ptr))
{
ptr++;
}
else
{
char *end;
switch (read)
{
case 0:
gtid->domain = strtol(ptr, &end, 10);
break;
case 1:
gtid->server_id = strtol(ptr, &end, 10);
break;
case 2:
gtid->seq = strtol(ptr, &end, 10);
break;
}
read++;
ptr = end;
}
}
}
/**
* Callback for GTID retrieval
* @param data User data
* @param ncolumns Number of columns
* @param values Row data
* @param names Field names
* @return 0 on success
*/
int gtid_query_cb(void* data, int ncolumns, char** values, char** names)
{
json_t *arr = (json_t*)data;
if (values[0])
{
json_array_append_new(arr, json_string(values[0]));
}
return 0;
}
/**
* Callback for GTID retrieval
* @param data User data
* @param ncolumns Number of columns
* @param values Row data
* @param names Field names
* @return 0 on success
*/
int gtid_query_cb_plain(void* data, int ncolumns, char** values, char** names)
{
DCB *dcb = (DCB *)data;
if (values[0])
{
dcb_printf(dcb, "%s ", values[0]);
}
return 0;
}
/**
* Add the tables involved in the latest transaction to a JSON object
*
* @param handle SQLite3 handle
* @param obj JSON object to add values to
* @param gtid GTID of the last transaction
*/
void add_used_tables(sqlite3 *handle, json_t* obj, gtid_pos_t* gtid)
{
char sql[AVRO_SQL_BUFFER_SIZE];
snprintf(sql, sizeof(sql), "SELECT table_name FROM "USED_TABLES_TABLE_NAME
" WHERE domain = %lu AND server_id = %lu AND sequence = %lu",
gtid->domain, gtid->server_id, gtid->seq);
char* errmsg;
json_t *arr = json_array();
if (sqlite3_exec(handle, sql, gtid_query_cb, arr,
&errmsg) != SQLITE_OK)
{
json_decref(arr);
MXS_ERROR("Failed to execute query: %s", errmsg);
}
else
{
json_object_set_new(obj, "tables", arr);
}
sqlite3_free(errmsg);
}
/**
* Get the tables involved in the latest transaction.
*
* Sqlite3 callback routine calls dcb_printf()
*
* @param router The AVRO router instance
* @param dcb The dcb to write data
*/
void avro_get_used_tables(AVRO_INSTANCE *router, DCB* dcb)
{
sqlite3 *handle = router->sqlite_handle;
char sql[AVRO_SQL_BUFFER_SIZE];
snprintf(sql, sizeof(sql), "SELECT table_name FROM "USED_TABLES_TABLE_NAME
" WHERE domain = %lu AND server_id = %lu AND sequence = %lu",
router->gtid.domain, router->gtid.server_id, router->gtid.seq);
char* errmsg;
/* call dcb_printf via callback */
if (sqlite3_exec(handle, sql, gtid_query_cb_plain, dcb,
&errmsg) != SQLITE_OK)
{
MXS_ERROR("Failed to execute query: %s", errmsg);
}
sqlite3_free(errmsg);
}
/**
* Callback for timestamp retrieval
*
* @param data User data
* @param ncolumns Number of columns
* @param values Row data
* @param names Field names
* @return 0 on success
*/
int timestamp_query_cb(void* data, int ncolumns, char** values, char** names)
{
long *val = (long*)data;
if (values[0])
{
*val = strtol(values[0], NULL, 10);
}
return 0;
}
/**
* Add the GTID timestamp to a JSON object
*
* @param handle
* @param obj
* @param gtid
*/
void add_timestamp(sqlite3 *handle, json_t* obj, gtid_pos_t* gtid)
{
char sql[AVRO_SQL_BUFFER_SIZE];
snprintf(sql, sizeof(sql), "SELECT DISTINCT binlog_timestamp FROM "USED_TABLES_TABLE_NAME
" WHERE domain = %lu AND server_id = %lu AND sequence = %lu",
gtid->domain, gtid->server_id, gtid->seq);
char* errmsg;
long ts = 0;
if (sqlite3_exec(handle, sql, timestamp_query_cb, &ts,
&errmsg) == SQLITE_OK)
{
json_object_set_new(obj, "timestamp", json_integer(ts));
}
else
{
MXS_ERROR("Failed to execute query: %s", errmsg);
}
sqlite3_free(errmsg);
}
/**
* Send information about the current GTID being processed
* @param router Router instance
* @param dcb Client DCB
*/
void send_gtid_info(AVRO_INSTANCE *router, gtid_pos_t *gtid_pos, DCB *dcb)
{
json_t *obj = json_object();
if (obj)
{
char gtid[256];
snprintf(gtid, sizeof(gtid), "%lu-%lu-%lu", gtid_pos->domain,
gtid_pos->server_id, gtid_pos->seq);
json_object_set_new(obj, "GTID", json_string(gtid));
// TODO: Store number of events in the database
json_object_set_new(obj, "events", json_integer(gtid_pos->event_num));
add_timestamp(router->sqlite_handle, obj, gtid_pos);
add_used_tables(router->sqlite_handle, obj, gtid_pos);
char *js = json_dumps(obj, 0);
size_t size = strlen(js);
GWBUF *buffer = gwbuf_alloc_and_load(size, js);
MXS_FREE(js);
dcb->func.write(dcb, buffer);
}
}
/**
* @brief Check if a file exists in a directory
*
* @param dir Directory where the file is searched
* @param file File to search
* @return True if file exists
*/
bool file_in_dir(const char *dir, const char *file)
{
char path[PATH_MAX + 1];
snprintf(path, sizeof(path), "%s/%s", dir, file);
return access(path, F_OK) == 0;
}
/**
* Process command from client
*
* @param router The router instance
* @param client The specific client data
* @param data GWBUF with command
*
*/
static void
avro_client_process_command(AVRO_INSTANCE *router, AVRO_CLIENT *client, GWBUF *queue)
{
const char req_data[] = "REQUEST-DATA";
const char req_last_gtid[] = "QUERY-LAST-TRANSACTION";
const char req_gtid[] = "QUERY-TRANSACTION";
const size_t req_data_len = sizeof(req_data) - 1;
size_t buflen = gwbuf_length(queue);
uint8_t data[buflen + 1];
gwbuf_copy_data(queue, 0, buflen, data);
data[buflen] = '\0';
char *command_ptr = strstr((char *)data, req_data);
if (command_ptr != NULL)
{
char *file_ptr = command_ptr + req_data_len;
int data_len = GWBUF_LENGTH(queue) - req_data_len;
if (data_len > 1)
{
const char *gtid_ptr = get_avrofile_name(file_ptr, data_len, client->avro_binfile);
if (gtid_ptr)
{
client->requested_gtid = true;
extract_gtid_request(&client->gtid, gtid_ptr, data_len - (gtid_ptr - file_ptr));
memcpy(&client->gtid_start, &client->gtid, sizeof(client->gtid_start));
}
if (file_in_dir(router->avrodir, client->avro_binfile))
{
/* set callback routine for data sending */
dcb_add_callback(client->dcb, DCB_REASON_DRAINED, avro_client_callback, client);
/* Add fake event that will call the avro_client_callback() routine */
poll_fake_write_event(client->dcb);
}
else
{
dcb_printf(client->dcb, "ERR NO-FILE File '%s' not found.", client->avro_binfile);
}
}
else
{
dcb_printf(client->dcb, "ERR REQUEST-DATA with no data");
}
}
/* Return last GTID info */
else if (strstr((char *)data, req_last_gtid))
{
send_gtid_info(router, &router->gtid, client->dcb);
}
/** Return requested GTID */
else if (strstr((char *)data, req_gtid))
{
gtid_pos_t gtid = {0, 0, 0, 0, 0};
extract_gtid_request(&gtid, (char*)data + sizeof(req_gtid),
GWBUF_LENGTH(queue) - sizeof(req_gtid));
send_gtid_info(router, &gtid, client->dcb);
}
else
{
GWBUF *reply = gwbuf_alloc(5);
memcpy(GWBUF_DATA(reply), "ECHO:", 5);
reply = gwbuf_append(reply, gwbuf_clone(queue));
client->dcb->func.write(client->dcb, reply);
}
}
/**
* @brief Form the full Avro file name
*
* @param file_ptr Requested file
* @param data_len Length of string pointed by @p file_ptr
* @param dest Destination where the file name is stored. Must be at least
* @p data_len + 1 bytes.
*/
const char* get_avrofile_name(const char *file_ptr, int data_len, char *dest)
{
while (isspace(*file_ptr))
{
file_ptr++;
data_len--;
}
char avro_file[data_len + 1];
memcpy(avro_file, file_ptr, data_len);
avro_file[data_len] = '\0';
char *cmd_sep = strchr(avro_file, ' ');
const char *rval = NULL;
if (cmd_sep)
{
*cmd_sep++ = '\0';
rval = file_ptr + (cmd_sep - avro_file);
ss_dassert(rval < file_ptr + data_len);
}
/** Exact file version specified */
if ((cmd_sep = strchr(avro_file, '.')) && (cmd_sep = strchr(cmd_sep + 1, '.')) &&
strlen(cmd_sep + 1) > 0)
{
snprintf(dest, AVRO_MAX_FILENAME_LEN, "%s.avro", avro_file);
}
/** No version specified, send all files */
else
{
snprintf(dest, AVRO_MAX_FILENAME_LEN, "%s.000001.avro", avro_file);
}
return rval;
}
static int send_row(DCB *dcb, json_t* row)
{
char *json = json_dumps(row, JSON_PRESERVE_ORDER);
size_t len = strlen(json);
GWBUF *buf = gwbuf_alloc(len + 1);
int rc = 0;
if (json && buf)
{
uint8_t *data = GWBUF_DATA(buf);
memcpy(data, json, len);
data[len] = '\n';
rc = dcb->func.write(dcb, buf);
}
else
{
MXS_ERROR("Failed to dump JSON value.");
rc = 0;
}
MXS_FREE(json);
return rc;
}
static void set_current_gtid(AVRO_CLIENT *client, json_t *row)
{
json_t *obj = json_object_get(row, avro_sequence);
ss_dassert(json_is_integer(obj));
client->gtid.seq = json_integer_value(obj);
obj = json_object_get(row, avro_server_id);
ss_dassert(json_is_integer(obj));
client->gtid.server_id = json_integer_value(obj);
obj = json_object_get(row, avro_domain);
ss_dassert(json_is_integer(obj));
client->gtid.domain = json_integer_value(obj);
}
/**
* @brief Stream Avro data in JSON format
*
* @param file File to stream from
* @param dcb DCB to stream to
* @return True if more data is readable, false if all data was sent
*/
static bool stream_json(AVRO_CLIENT *client)
{
int bytes = 0;
MAXAVRO_FILE *file = client->file_handle;
DCB *dcb = client->dcb;
do
{
json_t *row;
int rc = 1;
while (rc > 0 && (row = maxavro_record_read_json(file)))
{
rc = send_row(dcb, row);
set_current_gtid(client, row);
json_decref(row);
}
bytes += file->buffer_size;
}
while (maxavro_next_block(file) && bytes < AVRO_DATA_BURST_SIZE);
return bytes >= AVRO_DATA_BURST_SIZE;
}
/**
* @brief Stream Avro data in native Avro format
*
* @param file File to stream from
* @param dcb DCB to stream to
* @return True if streaming was successful, false if an error occurred
*/
static bool stream_binary(AVRO_CLIENT *client)
{
GWBUF *buffer;
uint64_t bytes = 0;
int rc = 1;
MAXAVRO_FILE *file = client->file_handle;
DCB *dcb = client->dcb;
while (rc > 0 && bytes < AVRO_DATA_BURST_SIZE)
{
bytes += file->buffer_size;
if ((buffer = maxavro_record_read_binary(file)))
{
rc = dcb->func.write(dcb, buffer);
}
else
{
rc = 0;
}
}
return bytes >= AVRO_DATA_BURST_SIZE;
}
static int sqlite_cb(void* data, int rows, char** values, char** names)
{
for (int i = 0; i < rows; i++)
{
if (values[i])
{
*((long*)data) = strtol(values[i], NULL, 10);
return 0;
}
}
return 0;
}
static const char select_template[] = "SELECT max(position) FROM gtid WHERE domain=%lu "
"AND server_id=%lu AND sequence <= %lu AND avrofile=\"%s\";";
static bool seek_to_index_pos(AVRO_CLIENT *client, MAXAVRO_FILE* file)
{
char *name = strrchr(client->file_handle->filename, '/');
ss_dassert(name);
name++;
char sql[sizeof(select_template) + NAME_MAX + 80];
snprintf(sql, sizeof(sql), select_template, client->gtid.domain,
client->gtid.server_id, client->gtid.seq, name);
long offset = -1;
char *errmsg = NULL;
bool rval = false;
if (sqlite3_exec(client->sqlite_handle, sql, sqlite_cb, &offset, &errmsg) == SQLITE_OK)
{
rval = true;
if (offset > 0 && !maxavro_record_set_pos(file, offset))
{
rval = false;
}
}
else
{
MXS_ERROR("Failed to query index position for GTID %lu-%lu-%lu: %s",
client->gtid.domain, client->gtid.server_id, client->gtid.seq, errmsg);
}
sqlite3_free(errmsg);
return rval;
}
/**
*
* @param client
* @param file
*/
static bool seek_to_gtid(AVRO_CLIENT *client, MAXAVRO_FILE* file)
{
bool seeking = true;
do
{
json_t *row;
while ((row = maxavro_record_read_json(file)))
{
json_t *obj = json_object_get(row, avro_sequence);
ss_dassert(json_is_integer(obj));
uint64_t value = json_integer_value(obj);
/** If a larger GTID is found, use that */
if (value >= client->gtid.seq)
{
obj = json_object_get(row, avro_server_id);
ss_dassert(json_is_integer(obj));
value = json_integer_value(obj);
if (value == client->gtid.server_id)
{
obj = json_object_get(row, avro_domain);
ss_dassert(json_is_integer(obj));
value = json_integer_value(obj);
if (value == client->gtid.domain)
{
MXS_INFO("Found GTID %lu-%lu-%lu for %s@%s",
client->gtid.domain, client->gtid.server_id,
client->gtid.seq, client->dcb->user, client->dcb->remote);
seeking = false;
}
}
}
/** We'll send the first found row immediately since we have already
* read the row into memory */
if (!seeking)
{
send_row(client->dcb, row);
}
json_decref(row);
}
}
while (seeking && maxavro_next_block(file));
return !seeking;
}
/**
* Print JSON output from selected AVRO file
*
* @param router The router instance
* @param client The specific client data
* @param avro_file The requested AVRO file
* @return True if more data needs to be read
*/
static bool avro_client_stream_data(AVRO_CLIENT *client)
{
bool read_more = false;
AVRO_INSTANCE *router = client->router;
if (strnlen(client->avro_binfile, 1))
{
char filename[PATH_MAX + 1];
snprintf(filename, PATH_MAX, "%s/%s", router->avrodir, client->avro_binfile);
bool ok = true;
spinlock_acquire(&client->file_lock);
if (client->file_handle == NULL &&
(client->file_handle = maxavro_file_open(filename)) == NULL)
{
ok = false;
}
spinlock_release(&client->file_lock);
if (ok)
{
switch (client->format)
{
case AVRO_FORMAT_JSON:
/** Currently only JSON format supports seeking to a GTID */
if (client->requested_gtid &&
seek_to_index_pos(client, client->file_handle) &&
seek_to_gtid(client, client->file_handle))
{
client->requested_gtid = false;
}
read_more = stream_json(client);
break;
case AVRO_FORMAT_AVRO:
read_more = stream_binary(client);
break;
default:
MXS_ERROR("Unexpected format: %d", client->format);
break;
}
if (maxavro_get_error(client->file_handle) != MAXAVRO_ERR_NONE)
{
MXS_ERROR("Reading Avro file failed with error '%s'.",
maxavro_get_error_string(client->file_handle));
}
/* update client struct */
memcpy(&client->avro_file, client->file_handle, sizeof(client->avro_file));
/* may be just use client->avro_file->records_read and remove this var */
client->last_sent_pos = client->avro_file.records_read;
}
}
else
{
fprintf(stderr, "No file specified\n");
dcb_printf(client->dcb, "ERR avro file not specified");
}
return read_more;
}
GWBUF* read_avro_json_schema(const char *avrofile, const char* dir)
{
GWBUF* rval = NULL;
const char *suffix = strrchr(avrofile, '.');
if (suffix)
{
char buffer[PATH_MAX + 1];
snprintf(buffer, sizeof(buffer), "%s/%.*s.avsc", dir, (int)(suffix - avrofile),
avrofile);
FILE *file = fopen(buffer, "rb");
if (file)
{
int nread;
while ((nread = fread(buffer, 1, sizeof(buffer) - 1, file)) > 0)
{
while (isspace(buffer[nread - 1]))
{
nread--;
}
buffer[nread++] = '\n';
GWBUF * newbuf = gwbuf_alloc_and_load(nread, buffer);
if (newbuf)
{
rval = gwbuf_append(rval, newbuf);
}
}
fclose(file);
}
else
{
MXS_ERROR("Failed to open file '%s': %d, %s", buffer, errno,
mxs_strerror(errno));
}
}
return rval;
}
GWBUF* read_avro_binary_schema(const char *avrofile, const char* dir)
{
GWBUF* rval = NULL;
char buffer[PATH_MAX + 1];
snprintf(buffer, sizeof(buffer), "%s/%s", dir, avrofile);
MAXAVRO_FILE *file = maxavro_file_open(buffer);
if (file)
{
rval = maxavro_file_binary_header(file);
maxavro_file_close(file);
}
else
{
MXS_ERROR("Failed to open file '%s'.", buffer);
}
return rval;
}
/**
* Rotate to a new Avro file
* @param client Avro client session
* @param fullname Absolute path to the file to rotate to
*/
static void rotate_avro_file(AVRO_CLIENT *client, char *fullname)
{
char *filename = strrchr(fullname, '/') + 1;
size_t len = strlen(filename);
if (len > AVRO_MAX_FILENAME_LEN)
{
// TODO: This function is in need of a return value. It would
// TODO: be better to abort if the name is too long and also
// TODO: if the opening of the file fails.
MXS_ERROR("Filename %s of length %lu is longer than maximum allowed "
"length %d. Trailing data will be cut.",
filename, len, AVRO_MAX_FILENAME_LEN);
len = AVRO_MAX_FILENAME_LEN;
}
strncpy(client->avro_binfile, filename, len);
client->avro_binfile[len] = 0;
client->last_sent_pos = 0;
spinlock_acquire(&client->file_lock);
maxavro_file_close(client->file_handle);
if ((client->file_handle = maxavro_file_open(fullname)) == NULL)
{
MXS_ERROR("Failed to open file: %s", filename);
}
else
{
MXS_INFO("Rotated '%s'@'%s' to file: %s", client->dcb->user,
client->dcb->remote, fullname);
}
spinlock_release(&client->file_lock);
}
/**
* Print the name of the next Avro file
* @param file Current filename
* @param dir Directory where the files exist
* @param dest Destination where the full path to the file is printed
* @param len Size of @p dest
*/
static void print_next_filename(const char *file, const char *dir, char *dest, size_t len)
{
char buffer[strlen(file) + 1];
strcpy(buffer, file);
char *ptr = strrchr(buffer, '.');
if (ptr)
{
ptr--;
while (ptr > buffer && *(ptr) != '.')
{
ptr--;
}
int filenum = strtol(ptr + 1, NULL, 10);
*ptr = '\0';
snprintf(dest, len, "%s/%s.%06d.avro",
dir, buffer, filenum + 1);
}
}
/**
* @brief The client callback for sending data
*
* @param dcb Client DCB
* @param reason Why the callback was called
* @param userdata Data provided when the callback was added
* @return Always 0
*/
int avro_client_callback(DCB *dcb, DCB_REASON reason, void *userdata)
{
if (reason == DCB_REASON_DRAINED)
{
AVRO_CLIENT *client = (AVRO_CLIENT*)userdata;
spinlock_acquire(&client->catch_lock);
if (client->cstate & AVRO_CS_BUSY)
{
spinlock_release(&client->catch_lock);
return 0;
}
client->cstate |= AVRO_CS_BUSY;
spinlock_release(&client->catch_lock);
if (client->last_sent_pos == 0)
{
/** Send the schema of the current file */
GWBUF *schema = NULL;
switch (client->format)
{
case AVRO_FORMAT_JSON:
schema = read_avro_json_schema(client->avro_binfile, client->router->avrodir);
break;
case AVRO_FORMAT_AVRO:
schema = read_avro_binary_schema(client->avro_binfile, client->router->avrodir);
break;
default:
MXS_ERROR("Unknown client format: %d", client->format);
}
if (schema)
{
client->dcb->func.write(client->dcb, schema);
}
}
/** Stream the data to the client */
bool read_more = avro_client_stream_data(client);
char filename[PATH_MAX + 1];
print_next_filename(client->avro_binfile, client->router->avrodir,
filename, sizeof(filename));
bool next_file;
/** If the next file is available, send it to the client */
if ((next_file = (access(filename, R_OK) == 0)))
{
rotate_avro_file(client, filename);
}
spinlock_acquire(&client->catch_lock);
client->cstate &= ~AVRO_CS_BUSY;
client->cstate |= AVRO_WAIT_DATA;
if (next_file || read_more)
{
#ifdef SS_DEBUG
if (read_more)
{
MXS_DEBUG("Burst limit hit, need to read more data.");
}
#endif
avro_notify_client(client);
}
spinlock_release(&client->catch_lock);
}
return 0;
}
/**
* @brief Notify a client that new data is available
*
* The client catch_lock must be held when calling this function.
*
* @param client Client to notify
*/
void avro_notify_client(AVRO_CLIENT *client)
{
/* Add fake event that will call the avro_client_callback() routine */
poll_fake_write_event(client->dcb);
client->cstate &= ~AVRO_WAIT_DATA;
}