JSON Impl and schema for BuildResult

doc/manual/package.nix

@@ -41,6 +41,7 @@ mkMesonDerivation (finalAttrs: {
         ../../src/libstore-tests/data/derived-path
         ../../src/libstore-tests/data/path-info
         ../../src/libstore-tests/data/nar-info
+        ../../src/libstore-tests/data/build-result
         # Too many different types of files to filter for now
         ../../doc/manual
         ./.

doc/manual/source/SUMMARY.md.in

@@ -127,6 +127,7 @@
     - [Derivation](protocols/json/derivation.md)
     - [Deriving Path](protocols/json/deriving-path.md)
     - [Build Trace Entry](protocols/json/build-trace-entry.md)
+    - [Build Result](protocols/json/build-result.md)
   - [Serving Tarball Flakes](protocols/tarball-fetcher.md)
   - [Store Path Specification](protocols/store-path.md)
   - [Nix Archive (NAR) Format](protocols/nix-archive/index.md)

doc/manual/source/protocols/json/build-result.md

@@ -0,0 +1,21 @@
+{{#include build-result-v1-fixed.md}}
+
+## Examples
+
+### Successful build
+
+```json
+{{#include schema/build-result-v1/success.json}}
+```
+
+### Failed build (output rejected)
+
+```json
+{{#include schema/build-result-v1/output-rejected.json}}
+```
+
+### Failed build (non-deterministic)
+
+```json
+{{#include schema/build-result-v1/not-deterministic.json}}
+```

doc/manual/source/protocols/json/meson.build

@@ -16,6 +16,7 @@ schemas = [
   'derivation-v3',
   'deriving-path-v1',
   'build-trace-entry-v1',
+  'build-result-v1',
 ]
 
 schema_files = files()

doc/manual/source/protocols/json/schema/build-result-v1

@@ -0,0 +1 @@
+../../../../../../src/libstore-tests/data/build-result

doc/manual/source/protocols/json/schema/build-result-v1.yaml

@@ -0,0 +1,136 @@
+"$schema": "http://json-schema.org/draft-04/schema"
+"$id": "https://nix.dev/manual/nix/latest/protocols/json/schema/build-result-v1.json"
+title: Build Result
+description: |
+  This schema describes the JSON representation of Nix's `BuildResult` type, which represents the result of building a derivation or substituting store paths.
+
+  Build results can represent either successful builds (with built outputs) or various types of failures.
+
+oneOf:
+  - "$ref": "#/$defs/success"
+  - "$ref": "#/$defs/failure"
+type: object
+required:
+  - success
+  - status
+properties:
+  timesBuilt:
+    type: integer
+    minimum: 0
+    title: Times built
+    description: |
+      How many times this build was performed.
+
+  startTime:
+    type: integer
+    minimum: 0
+    title: Start time
+    description: |
+      The start time of the build (or one of the rounds, if it was repeated), as a Unix timestamp.
+
+  stopTime:
+    type: integer
+    minimum: 0
+    title: Stop time
+    description: |
+      The stop time of the build (or one of the rounds, if it was repeated), as a Unix timestamp.
+
+  cpuUser:
+    type: integer
+    minimum: 0
+    title: User CPU time
+    description: |
+      User CPU time the build took, in microseconds.
+
+  cpuSystem:
+    type: integer
+    minimum: 0
+    title: System CPU time
+    description: |
+      System CPU time the build took, in microseconds.
+
+"$defs":
+  success:
+    type: object
+    title: Successful Build Result
+    description: |
+      Represents a successful build with built outputs.
+    required:
+      - success
+      - status
+      - builtOutputs
+    properties:
+      success:
+        const: true
+        title: Success indicator
+        description: |
+          Always true for successful build results.
+
+      status:
+        type: string
+        title: Success status
+        description: |
+          Status string for successful builds.
+        enum:
+          - "Built"
+          - "Substituted"
+          - "AlreadyValid"
+          - "ResolvesToAlreadyValid"
+
+      builtOutputs:
+        type: object
+        title: Built outputs
+        description: |
+          A mapping from output names to their build trace entries.
+        additionalProperties:
+          "$ref": "build-trace-entry-v1.yaml"
+
+  failure:
+    type: object
+    title: Failed Build Result
+    description: |
+      Represents a failed build with error information.
+    required:
+      - success
+      - status
+      - errorMsg
+    properties:
+      success:
+        const: false
+        title: Success indicator
+        description: |
+          Always false for failed build results.
+
+      status:
+        type: string
+        title: Failure status
+        description: |
+          Status string for failed builds.
+        enum:
+          - "PermanentFailure"
+          - "InputRejected"
+          - "OutputRejected"
+          - "TransientFailure"
+          - "CachedFailure"
+          - "TimedOut"
+          - "MiscFailure"
+          - "DependencyFailed"
+          - "LogLimitExceeded"
+          - "NotDeterministic"
+          - "NoSubstituters"
+          - "HashMismatch"
+
+      errorMsg:
+        type: string
+        title: Error message
+        description: |
+          Information about the error if the build failed.
+
+      isNonDeterministic:
+        type: boolean
+        title: Non-deterministic flag
+        description: |
+          If timesBuilt > 1, whether some builds did not produce the same result.
+
+          Note that 'isNonDeterministic = false' does not mean the build is deterministic,
+          just that we don't have evidence of non-determinism.

src/json-schema-checks/build-result

@@ -0,0 +1 @@
+../../src/libstore-tests/data/build-result

src/json-schema-checks/meson.build

@@ -150,6 +150,15 @@ schemas += [
       'impure.json',
     ],
   },
+  {
+    'stem' : 'build-result',
+    'schema' : schema_dir / 'build-result-v1.yaml',
+    'files' : [
+      'success.json',
+      'output-rejected.json',
+      'not-deterministic.json',
+    ],
+  },
   # Match exact variant
   {
     'stem' : 'store-object-info',

src/json-schema-checks/package.nix

@@ -28,6 +28,7 @@ mkMesonDerivation (finalAttrs: {
     ../../src/libstore-tests/data/derived-path
     ../../src/libstore-tests/data/path-info
     ../../src/libstore-tests/data/nar-info
+    ../../src/libstore-tests/data/build-result
     ./.
   ];
 

src/libstore-tests/build-result.cc

@@ -0,0 +1,108 @@
+#include <gtest/gtest.h>
+
+#include "nix/store/build-result.hh"
+#include "nix/util/tests/json-characterization.hh"
+
+namespace nix {
+
+class BuildResultTest : public virtual CharacterizationTest
+{
+    std::filesystem::path unitTestData = getUnitTestData() / "build-result";
+
+public:
+    std::filesystem::path goldenMaster(std::string_view testStem) const override
+    {
+        return unitTestData / testStem;
+    }
+};
+
+using nlohmann::json;
+
+struct BuildResultJsonTest : BuildResultTest,
+                             JsonCharacterizationTest<BuildResult>,
+                             ::testing::WithParamInterface<std::pair<std::string_view, BuildResult>>
+{};
+
+TEST_P(BuildResultJsonTest, from_json)
+{
+    auto & [name, expected] = GetParam();
+    readJsonTest(name, expected);
+}
+
+TEST_P(BuildResultJsonTest, to_json)
+{
+    auto & [name, value] = GetParam();
+    writeJsonTest(name, value);
+}
+
+using namespace std::literals::chrono_literals;
+
+INSTANTIATE_TEST_SUITE_P(
+    BuildResultJSON,
+    BuildResultJsonTest,
+    ::testing::Values(
+        std::pair{
+            "not-deterministic",
+            BuildResult{
+                .inner{BuildResult::Failure{
+                    .status = BuildResult::Failure::NotDeterministic,
+                    .errorMsg = "no idea why",
+                    .isNonDeterministic = false, // Note: This field is separate from the status
+                }},
+                .timesBuilt = 1,
+            },
+        },
+        std::pair{
+            "output-rejected",
+            BuildResult{
+                .inner{BuildResult::Failure{
+                    .status = BuildResult::Failure::OutputRejected,
+                    .errorMsg = "no idea why",
+                    .isNonDeterministic = false,
+                }},
+                .timesBuilt = 3,
+                .startTime = 30,
+                .stopTime = 50,
+            },
+        },
+        std::pair{
+            "success",
+            BuildResult{
+                .inner{BuildResult::Success{
+                    .status = BuildResult::Success::Built,
+                    .builtOutputs{
+                        {
+                            "foo",
+                            {
+                                {
+                                    .outPath = StorePath{"g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo"},
+                                },
+                                DrvOutput{
+                                    .drvHash = Hash::parseSRI("sha256-b4afnqKCO9oWXgYHb9DeQ2berSwOjS27rSd9TxXDc/U="),
+                                    .outputName = "foo",
+                                },
+                            },
+                        },
+                        {
+                            "bar",
+                            {
+                                {
+                                    .outPath = StorePath{"g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-bar"},
+                                },
+                                DrvOutput{
+                                    .drvHash = Hash::parseSRI("sha256-b4afnqKCO9oWXgYHb9DeQ2berSwOjS27rSd9TxXDc/U="),
+                                    .outputName = "bar",
+                                },
+                            },
+                        },
+                    },
+                }},
+                .timesBuilt = 3,
+                .startTime = 30,
+                .stopTime = 50,
+                .cpuUser = std::chrono::microseconds(500s),
+                .cpuSystem = std::chrono::microseconds(604s),
+            },
+        }));
+
+} // namespace nix

src/libstore-tests/data/build-result/not-deterministic.json

@@ -0,0 +1,9 @@
+{
+  "errorMsg": "no idea why",
+  "isNonDeterministic": false,
+  "startTime": 0,
+  "status": "NotDeterministic",
+  "stopTime": 0,
+  "success": false,
+  "timesBuilt": 1
+}

src/libstore-tests/data/build-result/output-rejected.json

@@ -0,0 +1,9 @@
+{
+  "errorMsg": "no idea why",
+  "isNonDeterministic": false,
+  "startTime": 30,
+  "status": "OutputRejected",
+  "stopTime": 50,
+  "success": false,
+  "timesBuilt": 3
+}

src/libstore-tests/data/build-result/success.json

@@ -0,0 +1,23 @@
+{
+  "builtOutputs": {
+    "bar": {
+      "dependentRealisations": {},
+      "id": "sha256:6f869f9ea2823bda165e06076fd0de4366dead2c0e8d2dbbad277d4f15c373f5!bar",
+      "outPath": "g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-bar",
+      "signatures": []
+    },
+    "foo": {
+      "dependentRealisations": {},
+      "id": "sha256:6f869f9ea2823bda165e06076fd0de4366dead2c0e8d2dbbad277d4f15c373f5!foo",
+      "outPath": "g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo",
+      "signatures": []
+    }
+  },
+  "cpuSystem": 604000000,
+  "cpuUser": 500000000,
+  "startTime": 30,
+  "status": "Built",
+  "stopTime": 50,
+  "success": true,
+  "timesBuilt": 3
+}

src/libstore-tests/meson.build

@@ -54,6 +54,7 @@ deps_private += gtest
 subdir('nix-meson-build-support/common')
 
 sources = files(
+  'build-result.cc',
   'common-protocol.cc',
   'content-address.cc',
   'derivation-advanced-attrs.cc',

src/libstore/build-result.cc

@@ -1,4 +1,6 @@
 #include "nix/store/build-result.hh"
+#include "nix/util/json-utils.hh"
+#include <array>
 
 namespace nix {
 
@@ -11,4 +13,144 @@ std::strong_ordering BuildResult::Success::operator<=>(const BuildResult::Succes
 bool BuildResult::Failure::operator==(const BuildResult::Failure &) const noexcept = default;
 std::strong_ordering BuildResult::Failure::operator<=>(const BuildResult::Failure &) const noexcept = default;
 
+static constexpr std::array<std::pair<BuildResult::Success::Status, std::string_view>, 4> successStatusStrings{{
+#define ENUM_ENTRY(e) {BuildResult::Success::e, #e}
+    ENUM_ENTRY(Built),
+    ENUM_ENTRY(Substituted),
+    ENUM_ENTRY(AlreadyValid),
+    ENUM_ENTRY(ResolvesToAlreadyValid),
+#undef ENUM_ENTRY
+}};
+
+static std::string_view successStatusToString(BuildResult::Success::Status status)
+{
+    for (const auto & [enumVal, str] : successStatusStrings) {
+        if (enumVal == status)
+            return str;
+    }
+    throw Error("unknown success status: %d", static_cast<int>(status));
+}
+
+static BuildResult::Success::Status successStatusFromString(std::string_view str)
+{
+    for (const auto & [enumVal, enumStr] : successStatusStrings) {
+        if (enumStr == str)
+            return enumVal;
+    }
+    throw Error("unknown built result success status '%s'", str);
+}
+
+static constexpr std::array<std::pair<BuildResult::Failure::Status, std::string_view>, 12> failureStatusStrings{{
+#define ENUM_ENTRY(e) {BuildResult::Failure::e, #e}
+    ENUM_ENTRY(PermanentFailure),
+    ENUM_ENTRY(InputRejected),
+    ENUM_ENTRY(OutputRejected),
+    ENUM_ENTRY(TransientFailure),
+    ENUM_ENTRY(CachedFailure),
+    ENUM_ENTRY(TimedOut),
+    ENUM_ENTRY(MiscFailure),
+    ENUM_ENTRY(DependencyFailed),
+    ENUM_ENTRY(LogLimitExceeded),
+    ENUM_ENTRY(NotDeterministic),
+    ENUM_ENTRY(NoSubstituters),
+    ENUM_ENTRY(HashMismatch),
+#undef ENUM_ENTRY
+}};
+
+static std::string_view failureStatusToString(BuildResult::Failure::Status status)
+{
+    for (const auto & [enumVal, str] : failureStatusStrings) {
+        if (enumVal == status)
+            return str;
+    }
+    throw Error("unknown failure status: %d", static_cast<int>(status));
+}
+
+static BuildResult::Failure::Status failureStatusFromString(std::string_view str)
+{
+    for (const auto & [enumVal, enumStr] : failureStatusStrings) {
+        if (enumStr == str)
+            return enumVal;
+    }
+    throw Error("unknown built result failure status '%s'", str);
+}
+
 } // namespace nix
+
+namespace nlohmann {
+
+using namespace nix;
+
+void adl_serializer<BuildResult>::to_json(json & res, const BuildResult & br)
+{
+    res = json::object();
+
+    // Common fields
+    res["timesBuilt"] = br.timesBuilt;
+    res["startTime"] = br.startTime;
+    res["stopTime"] = br.stopTime;
+
+    if (br.cpuUser.has_value()) {
+        res["cpuUser"] = br.cpuUser->count();
+    }
+    if (br.cpuSystem.has_value()) {
+        res["cpuSystem"] = br.cpuSystem->count();
+    }
+
+    // Handle success or failure variant
+    std::visit(
+        overloaded{
+            [&](const BuildResult::Success & success) {
+                res["success"] = true;
+                res["status"] = successStatusToString(success.status);
+                res["builtOutputs"] = success.builtOutputs;
+            },
+            [&](const BuildResult::Failure & failure) {
+                res["success"] = false;
+                res["status"] = failureStatusToString(failure.status);
+                res["errorMsg"] = failure.errorMsg;
+                res["isNonDeterministic"] = failure.isNonDeterministic;
+            },
+        },
+        br.inner);
+}
+
+BuildResult adl_serializer<BuildResult>::from_json(const json & _json)
+{
+    auto & json = getObject(_json);
+
+    BuildResult br;
+
+    // Common fields
+    br.timesBuilt = getUnsigned(valueAt(json, "timesBuilt"));
+    br.startTime = getUnsigned(valueAt(json, "startTime"));
+    br.stopTime = getUnsigned(valueAt(json, "stopTime"));
+
+    if (auto cpuUser = optionalValueAt(json, "cpuUser")) {
+        br.cpuUser = std::chrono::microseconds(getUnsigned(*cpuUser));
+    }
+    if (auto cpuSystem = optionalValueAt(json, "cpuSystem")) {
+        br.cpuSystem = std::chrono::microseconds(getUnsigned(*cpuSystem));
+    }
+
+    // Determine success or failure based on success field
+    bool success = getBoolean(valueAt(json, "success"));
+    std::string statusStr = getString(valueAt(json, "status"));
+
+    if (success) {
+        BuildResult::Success s;
+        s.status = successStatusFromString(statusStr);
+        s.builtOutputs = valueAt(json, "builtOutputs");
+        br.inner = std::move(s);
+    } else {
+        BuildResult::Failure f;
+        f.status = failureStatusFromString(statusStr);
+        f.errorMsg = getString(valueAt(json, "errorMsg"));
+        f.isNonDeterministic = getBoolean(valueAt(json, "isNonDeterministic"));
+        br.inner = std::move(f);
+    }
+
+    return br;
+}
+
+} // namespace nlohmann

src/libstore/include/nix/store/build-result.hh

@@ -7,6 +7,7 @@
 
 #include "nix/store/derived-path.hh"
 #include "nix/store/realisation.hh"
+#include "nix/util/json-impls.hh"
 
 namespace nix {
 
@@ -175,3 +176,5 @@ struct KeyedBuildResult : BuildResult
 };
 
 } // namespace nix
+
+JSON_IMPL(nix::BuildResult)