libstore/derivation-goal: avoid double-parsing of JSON messages

To avoid that JSON messages are parsed twice in case of
remote builds with `ssh-ng://`, I split up the original
`handleJSONLogMessage` into three parts:

* `parseJSONMessage(const std::string&)` checks if it's a message in the
  form of `@nix {...}` and tries to parse it (and prints an error if the
  parsing fails).
* `handleJSONLogMessage(nlohmann::json&, ...)` reads the fields from the
  message and passes them to the logger.
* `handleJSONLogMessage(const std::string&, ...)` behaves as before, but
  uses the two functions mentioned above as implementation.

In case of `ssh-ng://`-logs the first two methods are invoked manually.
This commit is contained in:
Maximilian Bosch 2022-02-19 22:34:50 +01:00
parent 7a04839ea5
commit cd92ea5885
No known key found for this signature in database
GPG key ID: 091DBF4D1FC46B8E
3 changed files with 64 additions and 42 deletions

View file

@ -1207,14 +1207,16 @@ void DerivationGoal::handleChildOutput(int fd, std::string_view data)
if (hook && fd == hook->fromHook.readSide.get()) {
for (auto c : data)
if (c == '\n') {
auto s = handleJSONLogMessage(currentHookLine, worker.act, hook->activities, true);
auto json = parseJSONMessage(currentHookLine);
if (json) {
auto s = handleJSONLogMessage(*json, worker.act, hook->activities, true);
if (s && !isWrittenToLog && logSink) {
auto json = nlohmann::json::parse(std::string(currentHookLine, 5));
if (json["type"] == resBuildLogLine) {
auto f = json["fields"];
if ((*json)["type"] == resBuildLogLine) {
auto f = (*json)["fields"];
(*logSink)((f.size() > 0 ? f.at(0).get<std::string>() : "") + "\n");
}
}
}
currentHookLine.clear();
} else
currentHookLine += c;

View file

@ -266,14 +266,21 @@ static Logger::Fields getFields(nlohmann::json & json)
return fields;
}
bool handleJSONLogMessage(const std::string & msg,
const Activity & act, std::map<ActivityId, Activity> & activities, bool trusted)
std::optional<nlohmann::json> parseJSONMessage(const std::string & msg)
{
if (!hasPrefix(msg, "@nix ")) return false;
if (!hasPrefix(msg, "@nix ")) return std::nullopt;
try {
auto json = nlohmann::json::parse(std::string(msg, 5));
return nlohmann::json::parse(std::string(msg, 5));
} catch (std::exception & e) {
printError("bad JSON log message from builder: %s", e.what());
}
return std::nullopt;
}
bool handleJSONLogMessage(nlohmann::json & json,
const Activity & act, std::map<ActivityId, Activity> & activities,
bool trusted)
{
std::string action = json["action"];
if (action == "start") {
@ -304,13 +311,18 @@ bool handleJSONLogMessage(const std::string & msg,
logger->log((Verbosity) json["level"], msg);
}
} catch (std::exception & e) {
printError("bad JSON log message from builder: %s", e.what());
}
return true;
}
bool handleJSONLogMessage(const std::string & msg,
const Activity & act, std::map<ActivityId, Activity> & activities, bool trusted)
{
auto json = parseJSONMessage(msg);
if (!json) return false;
return handleJSONLogMessage(*json, act, activities, trusted);
}
Activity::~Activity()
{
try {

View file

@ -4,6 +4,8 @@
#include "error.hh"
#include "config.hh"
#include <nlohmann/json.hpp>
namespace nix {
typedef enum {
@ -166,6 +168,12 @@ Logger * makeSimpleLogger(bool printBuildLogs = true);
Logger * makeJSONLogger(Logger & prevLogger);
std::optional<nlohmann::json> parseJSONMessage(const std::string & msg);
bool handleJSONLogMessage(nlohmann::json & json,
const Activity & act, std::map<ActivityId, Activity> & activities,
bool trusted);
bool handleJSONLogMessage(const std::string & msg,
const Activity & act, std::map<ActivityId, Activity> & activities,
bool trusted);