Nginx OTel module.
This commit is contained in:
Pavel Pautov
Dmitry Plotnikov
parent
0cce01b3c7
commit
9d3e21194c
8 changed files with 963 additions and 0 deletions
452
src/http_module.cpp
Normal file
452
src/http_module.cpp
Normal file
|
|
@ -0,0 +1,452 @@
|
|||
extern "C" {
|
||||
#include <ngx_config.h>
|
||||
#include <ngx_core.h>
|
||||
#include <ngx_http.h>
|
||||
}
|
||||
|
||||
#include "str_view.hpp"
|
||||
#include "trace_context.hpp"
|
||||
#include "batch_exporter.hpp"
|
||||
|
||||
extern ngx_module_t gHttpModule;
|
||||
|
||||
namespace {
|
||||
|
||||
struct MainConf {
|
||||
ngx_str_t endpoint;
|
||||
ngx_msec_t interval;
|
||||
size_t batchSize;
|
||||
size_t batchCount;
|
||||
|
||||
ngx_str_t serviceName;
|
||||
};
|
||||
|
||||
struct LocationConf {
|
||||
ngx_http_complex_value_t* trace;
|
||||
};
|
||||
|
||||
char* setExporter(ngx_conf_t* cf, ngx_command_t* cmd, void* conf);
|
||||
|
||||
ngx_command_t gCommands[] = {
|
||||
|
||||
{ ngx_string("otel_exporter"),
|
||||
NGX_HTTP_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_NOARGS,
|
||||
setExporter,
|
||||
NGX_HTTP_MAIN_CONF_OFFSET },
|
||||
|
||||
{ ngx_string("otel_service_name"),
|
||||
NGX_HTTP_MAIN_CONF|NGX_CONF_TAKE1,
|
||||
ngx_conf_set_str_slot,
|
||||
NGX_HTTP_MAIN_CONF_OFFSET,
|
||||
offsetof(MainConf, serviceName) },
|
||||
|
||||
{ ngx_string("otel_trace"),
|
||||
NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
|
||||
ngx_http_set_complex_value_slot,
|
||||
NGX_HTTP_LOC_CONF_OFFSET,
|
||||
offsetof(LocationConf, trace) },
|
||||
|
||||
ngx_null_command
|
||||
};
|
||||
|
||||
ngx_command_t gExporterCommands[] = {
|
||||
|
||||
{ ngx_string("endpoint"),
|
||||
NGX_CONF_TAKE1,
|
||||
ngx_conf_set_str_slot,
|
||||
0,
|
||||
offsetof(MainConf, endpoint) },
|
||||
|
||||
{ ngx_string("interval"),
|
||||
NGX_CONF_TAKE1,
|
||||
ngx_conf_set_msec_slot,
|
||||
0,
|
||||
offsetof(MainConf, interval) },
|
||||
|
||||
{ ngx_string("batch_size"),
|
||||
NGX_CONF_TAKE1,
|
||||
ngx_conf_set_size_slot,
|
||||
0,
|
||||
offsetof(MainConf, batchSize) },
|
||||
|
||||
{ ngx_string("batch_count"),
|
||||
NGX_CONF_TAKE1,
|
||||
ngx_conf_set_size_slot,
|
||||
0,
|
||||
offsetof(MainConf, batchCount) },
|
||||
|
||||
ngx_null_command
|
||||
};
|
||||
|
||||
std::unique_ptr<BatchExporter> gExporter;
|
||||
|
||||
StrView toStrView(ngx_str_t str)
|
||||
{
|
||||
return StrView((char*)str.data, str.len);
|
||||
}
|
||||
|
||||
ngx_int_t onRequestStart(ngx_http_request_t* r)
|
||||
{
|
||||
// don't let internal redirects to override sampling decision
|
||||
if (r->internal) {
|
||||
return NGX_DECLINED;
|
||||
}
|
||||
|
||||
bool sampled = false;
|
||||
|
||||
auto lcf = (LocationConf*)ngx_http_get_module_loc_conf(r, gHttpModule);
|
||||
if (lcf->trace != NULL) {
|
||||
ngx_str_t trace;
|
||||
if (ngx_http_complex_value(r, lcf->trace, &trace) != NGX_OK) {
|
||||
return NGX_ERROR;
|
||||
}
|
||||
|
||||
sampled = toStrView(trace) == "on";
|
||||
}
|
||||
|
||||
if (sampled) {
|
||||
ngx_http_set_ctx(r, &gHttpModule, gHttpModule);
|
||||
}
|
||||
|
||||
return NGX_DECLINED;
|
||||
}
|
||||
|
||||
StrView getServerName(ngx_http_request_t* r)
|
||||
{
|
||||
auto cscf = (ngx_http_core_srv_conf_t*)
|
||||
ngx_http_get_module_srv_conf(r, ngx_http_core_module);
|
||||
|
||||
auto name = cscf->server_name;
|
||||
if (name.len == 0) {
|
||||
name = r->headers_in.server;
|
||||
}
|
||||
|
||||
return toStrView(name);
|
||||
}
|
||||
|
||||
void addDefaultAttrs(BatchExporter::Span& span, ngx_http_request_t* r)
|
||||
{
|
||||
// based on trace semantic conventions for HTTP from 1.16.0 OTel spec
|
||||
|
||||
span.add("http.method", toStrView(r->method_name));
|
||||
|
||||
span.add("http.target", toStrView(r->unparsed_uri));
|
||||
|
||||
auto clcf = (ngx_http_core_loc_conf_t*)
|
||||
ngx_http_get_module_loc_conf(r, ngx_http_core_module);
|
||||
if (clcf->name.len) {
|
||||
span.add("http.route", toStrView(clcf->name));
|
||||
}
|
||||
|
||||
span.add("http.scheme", r->connection->ssl ? "https" : "http");
|
||||
|
||||
auto protocol = toStrView(r->http_protocol);
|
||||
if (protocol.size() > 5) { // "HTTP/"
|
||||
span.add("http.flavor", protocol.substr(5));
|
||||
}
|
||||
|
||||
if (r->headers_in.user_agent) {
|
||||
span.add("http.user_agent", toStrView(r->headers_in.user_agent->value));
|
||||
}
|
||||
|
||||
auto received = r->headers_in.content_length_n;
|
||||
span.add("http.request_content_length", received > 0 ? received : 0);
|
||||
|
||||
auto sent = r->connection->sent - (off_t)r->header_size;
|
||||
span.add("http.response_content_length", sent > 0 ? sent : 0);
|
||||
|
||||
auto status = r->err_status ? r->err_status : r->headers_out.status;
|
||||
if (status) {
|
||||
span.add("http.status_code", status);
|
||||
|
||||
if (status >= 500) {
|
||||
span.setError();
|
||||
}
|
||||
}
|
||||
|
||||
span.add("net.host.name", getServerName(r));
|
||||
|
||||
if (ngx_connection_local_sockaddr(r->connection, NULL, 0) == NGX_OK) {
|
||||
auto port = ngx_inet_get_port(r->connection->local_sockaddr);
|
||||
auto defaultPort = r->connection->ssl ? 443 : 80;
|
||||
|
||||
if (port != defaultPort) {
|
||||
span.add("net.host.port", port);
|
||||
}
|
||||
}
|
||||
|
||||
span.add("net.sock.peer.addr", toStrView(r->connection->addr_text));
|
||||
span.add("net.sock.peer.port", ngx_inet_get_port(r->connection->sockaddr));
|
||||
}
|
||||
|
||||
ngx_int_t onRequestEnd(ngx_http_request_t* r)
|
||||
{
|
||||
if (!ngx_http_get_module_ctx(r, gHttpModule)) {
|
||||
return NGX_DECLINED;
|
||||
}
|
||||
|
||||
auto clcf = (ngx_http_core_loc_conf_t*)ngx_http_get_module_loc_conf(
|
||||
r, ngx_http_core_module);
|
||||
|
||||
auto now = ngx_timeofday();
|
||||
|
||||
auto toNanoSec = [](time_t sec, ngx_msec_t msec) -> uint64_t {
|
||||
return (sec * 1000 + msec) * 1000000;
|
||||
};
|
||||
|
||||
try {
|
||||
BatchExporter::SpanInfo info{
|
||||
toStrView(clcf->name), TraceContext::generate(true), {},
|
||||
toNanoSec(r->start_sec, r->start_msec),
|
||||
toNanoSec(now->sec, now->msec)};
|
||||
|
||||
bool ok = gExporter->add(info, [r](BatchExporter::Span& span) {
|
||||
addDefaultAttrs(span, r);
|
||||
});
|
||||
|
||||
if (!ok) {
|
||||
static size_t dropped = 0;
|
||||
static time_t lastLog = 0;
|
||||
++dropped;
|
||||
if (lastLog != ngx_time()) {
|
||||
lastLog = ngx_time();
|
||||
ngx_log_error(NGX_LOG_NOTICE, r->connection->log, 0,
|
||||
"OTel dropped records: %uz", dropped);
|
||||
}
|
||||
}
|
||||
|
||||
} catch (const std::exception& e) {
|
||||
ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
|
||||
"OTel failed to add span: %s", e.what());
|
||||
return NGX_ERROR;
|
||||
}
|
||||
|
||||
return NGX_DECLINED;
|
||||
}
|
||||
|
||||
ngx_int_t initModule(ngx_conf_t* cf)
|
||||
{
|
||||
auto cmcf = (ngx_http_core_main_conf_t*)ngx_http_conf_get_module_main_conf(
|
||||
cf, ngx_http_core_module);
|
||||
|
||||
auto h = (ngx_http_handler_pt*)ngx_array_push(
|
||||
&cmcf->phases[NGX_HTTP_REWRITE_PHASE].handlers);
|
||||
if (h == NULL) {
|
||||
return NGX_ERROR;
|
||||
}
|
||||
|
||||
*h = onRequestStart;
|
||||
|
||||
h = (ngx_http_handler_pt*)ngx_array_push(
|
||||
&cmcf->phases[NGX_HTTP_LOG_PHASE].handlers);
|
||||
if (h == NULL) {
|
||||
return NGX_ERROR;
|
||||
}
|
||||
|
||||
*h = onRequestEnd;
|
||||
|
||||
return NGX_OK;
|
||||
}
|
||||
|
||||
ngx_int_t initWorkerProcess(ngx_cycle_t* cycle)
|
||||
{
|
||||
auto mcf = (MainConf*)ngx_http_cycle_get_module_main_conf(
|
||||
cycle, gHttpModule);
|
||||
|
||||
try {
|
||||
gExporter.reset(new BatchExporter(
|
||||
toStrView(mcf->endpoint),
|
||||
mcf->batchSize,
|
||||
mcf->batchCount,
|
||||
toStrView(mcf->serviceName)));
|
||||
} catch (const std::exception& e) {
|
||||
ngx_log_error(NGX_LOG_CRIT, cycle->log, 0,
|
||||
"OTel worker init error: %s", e.what());
|
||||
return NGX_ERROR;
|
||||
}
|
||||
|
||||
static ngx_connection_t dummy;
|
||||
static ngx_event_t flushEvent;
|
||||
|
||||
flushEvent.data = &dummy;
|
||||
flushEvent.log = cycle->log;
|
||||
flushEvent.cancelable = 1;
|
||||
flushEvent.handler = [](ngx_event_t* ev) {
|
||||
try {
|
||||
gExporter->flush();
|
||||
} catch (const std::exception& e) {
|
||||
ngx_log_error(NGX_LOG_CRIT, ev->log, 0,
|
||||
"OTel flush error: %s", e.what());
|
||||
}
|
||||
|
||||
auto mcf = (MainConf*)ngx_http_cycle_get_module_main_conf(
|
||||
ngx_cycle, gHttpModule);
|
||||
|
||||
ngx_add_timer(ev, mcf->interval);
|
||||
};
|
||||
|
||||
ngx_add_timer(&flushEvent, mcf->interval);
|
||||
|
||||
return NGX_OK;
|
||||
}
|
||||
|
||||
void exitWorkerProcess(ngx_cycle_t* cycle)
|
||||
{
|
||||
try {
|
||||
gExporter->flush();
|
||||
} catch (const std::exception& e) {
|
||||
ngx_log_error(NGX_LOG_CRIT, cycle->log, 0,
|
||||
"OTel flush error: %s", e.what());
|
||||
}
|
||||
|
||||
gExporter.reset();
|
||||
}
|
||||
|
||||
char* setExporter(ngx_conf_t* cf, ngx_command_t* cmd, void* conf)
|
||||
{
|
||||
auto mcf = (MainConf*)conf;
|
||||
|
||||
if (mcf->endpoint.len) {
|
||||
return (char*)"is duplicate";
|
||||
}
|
||||
|
||||
auto cfCopy = *cf;
|
||||
|
||||
cfCopy.handler = [](ngx_conf_t* cf, ngx_command_t*, void*) {
|
||||
auto name = (ngx_str_t*)cf->args->elts;
|
||||
|
||||
for (auto cmd = gExporterCommands; cmd->name.len; cmd++) {
|
||||
|
||||
if (ngx_strcmp(name->data, cmd->name.data) != 0) {
|
||||
continue;
|
||||
}
|
||||
|
||||
if (cf->args->nelts != 2) {
|
||||
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
||||
"invalid number of arguments in \"%V\" "
|
||||
"directive of \"otel_exporter\"", name);
|
||||
return (char*)NGX_CONF_ERROR;
|
||||
}
|
||||
|
||||
auto rv = cmd->set(cf, cmd, cf->handler_conf);
|
||||
|
||||
if (rv == NGX_CONF_OK) {
|
||||
return rv;
|
||||
}
|
||||
|
||||
if (rv != NGX_CONF_ERROR) {
|
||||
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
||||
"\"%V\" directive of \"otel_exporter\" %s", name, rv);
|
||||
}
|
||||
|
||||
return (char*)NGX_CONF_ERROR;
|
||||
}
|
||||
|
||||
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
||||
"unknown directive \"%V\" in \"otel_exporter\"", name);
|
||||
return (char*)NGX_CONF_ERROR;
|
||||
};
|
||||
|
||||
cfCopy.handler_conf = mcf;
|
||||
|
||||
auto rv = ngx_conf_parse(&cfCopy, NULL);
|
||||
if (rv != NGX_CONF_OK) {
|
||||
return rv;
|
||||
}
|
||||
|
||||
if (mcf->endpoint.len == 0) {
|
||||
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
||||
"\"otel_exporter\" requires \"endpoint\"");
|
||||
return (char*)NGX_CONF_ERROR;
|
||||
}
|
||||
|
||||
return NGX_CONF_OK;
|
||||
}
|
||||
|
||||
void* createMainConf(ngx_conf_t* cf)
|
||||
{
|
||||
auto mcf = (MainConf*)ngx_pcalloc(cf->pool, sizeof(MainConf));
|
||||
if (mcf == NULL) {
|
||||
return NULL;
|
||||
}
|
||||
|
||||
mcf->interval = NGX_CONF_UNSET_MSEC;
|
||||
mcf->batchSize = NGX_CONF_UNSET_SIZE;
|
||||
mcf->batchCount = NGX_CONF_UNSET_SIZE;
|
||||
|
||||
return mcf;
|
||||
}
|
||||
|
||||
char* initMainConf(ngx_conf_t* cf, void* conf)
|
||||
{
|
||||
auto mcf = (MainConf*)conf;
|
||||
|
||||
if (mcf->endpoint.len == 0) {
|
||||
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
||||
"\"otel_exporter\" block is missing");
|
||||
return (char*)NGX_CONF_ERROR;
|
||||
}
|
||||
|
||||
ngx_conf_init_msec_value(mcf->interval, 5000);
|
||||
ngx_conf_init_size_value(mcf->batchSize, 512);
|
||||
ngx_conf_init_size_value(mcf->batchCount, 4);
|
||||
|
||||
if (mcf->serviceName.data == NULL) {
|
||||
mcf->serviceName = ngx_string("unknown_service:nginx");
|
||||
}
|
||||
|
||||
return NGX_CONF_OK;
|
||||
}
|
||||
|
||||
void* createLocationConf(ngx_conf_t* cf)
|
||||
{
|
||||
auto conf = (LocationConf*)ngx_pcalloc(cf->pool, sizeof(LocationConf));
|
||||
if (conf == NULL) {
|
||||
return NULL;
|
||||
}
|
||||
|
||||
conf->trace = (ngx_http_complex_value_t*)NGX_CONF_UNSET_PTR;
|
||||
|
||||
return conf;
|
||||
}
|
||||
|
||||
char* mergeLocationConf(ngx_conf_t* cf, void* parent, void* child)
|
||||
{
|
||||
auto prev = (LocationConf*)parent;
|
||||
auto conf = (LocationConf*)child;
|
||||
|
||||
ngx_conf_merge_ptr_value(conf->trace, prev->trace, NULL);
|
||||
|
||||
return NGX_CONF_OK;
|
||||
}
|
||||
|
||||
ngx_http_module_t gHttpModuleCtx = {
|
||||
NULL, /* preconfiguration */
|
||||
initModule, /* postconfiguration */
|
||||
|
||||
createMainConf, /* create main configuration */
|
||||
initMainConf, /* init main configuration */
|
||||
|
||||
NULL, /* create server configuration */
|
||||
NULL, /* merge server configuration */
|
||||
|
||||
createLocationConf, /* create location configuration */
|
||||
mergeLocationConf /* merge location configuration */
|
||||
};
|
||||
|
||||
}
|
||||
|
||||
ngx_module_t gHttpModule = {
|
||||
NGX_MODULE_V1,
|
||||
&gHttpModuleCtx, /* module context */
|
||||
gCommands, /* module directives */
|
||||
NGX_HTTP_MODULE, /* module type */
|
||||
NULL, /* init master */
|
||||
NULL, /* init module */
|
||||
initWorkerProcess, /* init process */
|
||||
NULL, /* init thread */
|
||||
NULL, /* exit thread */
|
||||
exitWorkerProcess, /* exit process */
|
||||
NULL, /* exit master */
|
||||
NGX_MODULE_V1_PADDING
|
||||
};
|
||||
Loading…
Add table
Add a link
Reference in a new issue