blob: 2f92c9e1a8fc153bb95bf8744b61978c0ef0e2d3 [file] [log] [blame]
/*
* Copyright (C) Igor Sysoev
* Copyright (C) Nginx, Inc.
*/
#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>
typedef struct {
uint32_t percent;
ngx_http_variable_value_t value;
} ngx_http_split_clients_part_t;
typedef struct {
ngx_http_complex_value_t value;
ngx_array_t parts;
} ngx_http_split_clients_ctx_t;
static char *ngx_conf_split_clients_block(ngx_conf_t *cf, ngx_command_t *cmd,
void *conf);
static char *ngx_http_split_clients(ngx_conf_t *cf, ngx_command_t *dummy,
void *conf);
static ngx_command_t ngx_http_split_clients_commands[] = {
{ ngx_string("split_clients"),
NGX_HTTP_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_TAKE2,
ngx_conf_split_clients_block,
NGX_HTTP_MAIN_CONF_OFFSET,
0,
NULL },
ngx_null_command
};
static ngx_http_module_t ngx_http_split_clients_module_ctx = {
NULL, /* preconfiguration */
NULL, /* postconfiguration */
NULL, /* create main configuration */
NULL, /* init main configuration */
NULL, /* create server configuration */
NULL, /* merge server configuration */
NULL, /* create location configuration */
NULL /* merge location configuration */
};
ngx_module_t ngx_http_split_clients_module = {
NGX_MODULE_V1,
&ngx_http_split_clients_module_ctx, /* module context */
ngx_http_split_clients_commands, /* module directives */
NGX_HTTP_MODULE, /* module type */
NULL, /* init master */
NULL, /* init module */
NULL, /* init process */
NULL, /* init thread */
NULL, /* exit thread */
NULL, /* exit process */
NULL, /* exit master */
NGX_MODULE_V1_PADDING
};
static ngx_int_t
ngx_http_split_clients_variable(ngx_http_request_t *r,
ngx_http_variable_value_t *v, uintptr_t data)
{
ngx_http_split_clients_ctx_t *ctx = (ngx_http_split_clients_ctx_t *) data;
uint32_t hash;
ngx_str_t val;
ngx_uint_t i;
ngx_http_split_clients_part_t *part;
*v = ngx_http_variable_null_value;
if (ngx_http_complex_value(r, &ctx->value, &val) != NGX_OK) {
return NGX_OK;
}
hash = ngx_murmur_hash2(val.data, val.len);
part = ctx->parts.elts;
for (i = 0; i < ctx->parts.nelts; i++) {
ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"http split: %uD %uD", hash, part[i].percent);
if (hash < part[i].percent || part[i].percent == 0) {
*v = part[i].value;
return NGX_OK;
}
}
return NGX_OK;
}
static char *
ngx_conf_split_clients_block(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
char *rv;
uint32_t sum, last;
ngx_str_t *value, name;
ngx_uint_t i;
ngx_conf_t save;
ngx_http_variable_t *var;
ngx_http_split_clients_ctx_t *ctx;
ngx_http_split_clients_part_t *part;
ngx_http_compile_complex_value_t ccv;
ctx = ngx_pcalloc(cf->pool, sizeof(ngx_http_split_clients_ctx_t));
if (ctx == NULL) {
return NGX_CONF_ERROR;
}
value = cf->args->elts;
ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));
ccv.cf = cf;
ccv.value = &value[1];
ccv.complex_value = &ctx->value;
if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
return NGX_CONF_ERROR;
}
name = value[2];
if (name.data[0] != '$') {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"invalid variable name \"%V\"", &name);
return NGX_CONF_ERROR;
}
name.len--;
name.data++;
var = ngx_http_add_variable(cf, &name, NGX_HTTP_VAR_CHANGEABLE);
if (var == NULL) {
return NGX_CONF_ERROR;
}
var->get_handler = ngx_http_split_clients_variable;
var->data = (uintptr_t) ctx;
if (ngx_array_init(&ctx->parts, cf->pool, 2,
sizeof(ngx_http_split_clients_part_t))
!= NGX_OK)
{
return NGX_CONF_ERROR;
}
save = *cf;
cf->ctx = ctx;
cf->handler = ngx_http_split_clients;
cf->handler_conf = conf;
rv = ngx_conf_parse(cf, NULL);
*cf = save;
if (rv != NGX_CONF_OK) {
return rv;
}
sum = 0;
last = 0;
part = ctx->parts.elts;
for (i = 0; i < ctx->parts.nelts; i++) {
sum = part[i].percent ? sum + part[i].percent : 10000;
if (sum > 10000) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"percent total is greater than 100%%");
return NGX_CONF_ERROR;
}
if (part[i].percent) {
last += part[i].percent * (uint64_t) 0xffffffff / 10000;
part[i].percent = last;
}
}
return rv;
}
static char *
ngx_http_split_clients(ngx_conf_t *cf, ngx_command_t *dummy, void *conf)
{
ngx_int_t n;
ngx_str_t *value;
ngx_http_split_clients_ctx_t *ctx;
ngx_http_split_clients_part_t *part;
ctx = cf->ctx;
value = cf->args->elts;
part = ngx_array_push(&ctx->parts);
if (part == NULL) {
return NGX_CONF_ERROR;
}
if (value[0].len == 1 && value[0].data[0] == '*') {
part->percent = 0;
} else {
if (value[0].len == 0 || value[0].data[value[0].len - 1] != '%') {
goto invalid;
}
n = ngx_atofp(value[0].data, value[0].len - 1, 2);
if (n == NGX_ERROR || n == 0) {
goto invalid;
}
part->percent = (uint32_t) n;
}
part->value.len = value[1].len;
part->value.valid = 1;
part->value.no_cacheable = 0;
part->value.not_found = 0;
part->value.data = value[1].data;
return NGX_CONF_OK;
invalid:
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"invalid percent value \"%V\"", &value[0]);
return NGX_CONF_ERROR;
}