lix/src/libexpr/value-to-json.cc

109 lines
2.9 KiB
C++

#include "value-to-json.hh"
#include "eval-inline.hh"
#include "util.hh"
#include <cstdlib>
#include <iomanip>
#include <nlohmann/json.hpp>
namespace nix {
using json = nlohmann::json;
json printValueAsJSON(EvalState & state, bool strict,
Value & v, const PosIdx pos, PathSet & context, bool copyToStore)
{
checkInterrupt();
if (strict) state.forceValue(v, pos);
json out;
switch (v.type()) {
case nInt:
out = v.integer;
break;
case nBool:
out = v.boolean;
break;
case nString:
copyContext(v, context);
out = v.string.s;
break;
case nPath:
if (copyToStore)
out = state.copyPathToStore(context, v.path);
else
out = v.path;
break;
case nNull:
break;
case nAttrs: {
auto maybeString = state.tryAttrsToString(pos, v, context, false, false);
if (maybeString) {
out = *maybeString;
break;
}
auto i = v.attrs->find(state.sOutPath);
if (i == v.attrs->end()) {
out = json::object();
StringSet names;
for (auto & j : *v.attrs)
names.emplace(state.symbols[j.name]);
for (auto & j : names) {
Attr & a(*v.attrs->find(state.symbols.create(j)));
out[j] = printValueAsJSON(state, strict, *a.value, a.pos, context, copyToStore);
}
} else
return printValueAsJSON(state, strict, *i->value, i->pos, context, copyToStore);
break;
}
case nList: {
out = json::array();
for (auto elem : v.listItems())
out.push_back(printValueAsJSON(state, strict, *elem, pos, context, copyToStore));
break;
}
case nExternal:
return v.external->printValueAsJSON(state, strict, context, copyToStore);
break;
case nFloat:
out = v.fpoint;
break;
case nThunk:
case nFunction:
auto e = TypeError({
.msg = hintfmt("cannot convert %1% to JSON", showType(v)),
.errPos = state.positions[v.determinePos(pos)]
});
e.addTrace(state.positions[pos], hintfmt("message for the trace"));
state.debugThrowLastTrace(e);
throw e;
}
return out;
}
void printValueAsJSON(EvalState & state, bool strict,
Value & v, const PosIdx pos, std::ostream & str, PathSet & context, bool copyToStore)
{
str << printValueAsJSON(state, strict, v, pos, context, copyToStore);
}
json ExternalValueBase::printValueAsJSON(EvalState & state, bool strict,
PathSet & context, bool copyToStore) const
{
state.debugThrowLastTrace(TypeError("cannot convert %1% to JSON", showType()));
}
}