XCLogParser

XCLogParser is a CLI tool that parses the SLF serialization format used by Xcode and xcodebuild to store its Build and Test logs (xcactivitylog files).

You can find more information about the format used in the logs here. You can also check Erick Camacho’s talk at AltConf 2019 about it.

The tool supports creating reports of different kinds to analyze the content of the logs. XCLogParser can give a lot of insights in regards to build times for every module and file in your project, warnings, errors and unit tests results.

This is an example of a report created from the Build Log of the Kickstarter iOS open source app.

How and Why

XCLogParser is written as a SPM executable and it supports three commands:

1. Dump the contents of an xcactivitylog into a JSON document.
2. Parse the contents of an xcactivitylog into different kind of reports (json, flatJson, summaryJson, chromeTracer, issues and html).
3. Dump the Manifest contents of a LogStoreManifest.plist file into a JSON document.

Depending on your needs, there are various use-cases where XCLogParser can help you:

• Understanding and detailed tracking of build times.
• Automatically retrieve unit test results, warnings and errors.
• Build other developer tools for usage outside Xcode.
• Automatically and continuously data delivery for historic analysis.

Installation

You can compile the executable with the command rake build[debug] or rake build[release] or simply use the Swift Package Manager commands directly. You can also run rake install to install the executable in your /usr/local/bin directory.

Homebrew

$ brew install xclogparser

We are currently working on adding more installation options.

Xcode Integration

You can automate the parsing of xcactivitylog files with a post-scheme build action. In this way, the last build log can be parsed as soon as a build finishes. To do that, open the scheme editor in a project and expand the “Build” panel on the left side. You can then add a new “Post-action” run script and invoke the xclogparser executable with the required parameters:

xclogparser parse --project MyApp --reporter html

This script assumes that the xclogparser executable is installed and present in your PATH.

The run script is executed in a temporary directory by Xcode, so you may find it useful to immediately open the generated output with open MyAppLogs at the end of the script.
The Finder will automatically open the output folder after a build completes and you can then view the generated HTML page that contains a nice visualization of your build! ✨

Tips & Tricks

1. Errors thrown in post-action run scripts are silenced, so it could be hard to notice simple mistakes.
2. Since Xcode 11, xcodebuild only generates the .xcactivitylog build logs when the option -resultBundlePath is present. If you’re compiling with that command and not with Xcode, be sure to set that option to a valid path ending in .xcresult.
3. Xcode likes to wait for all subprocesses to exit before completing the build. For this reason, you may notice a delayed “Build Succeeded” message if your post-scheme action is taking too long to execute. You can workaround this by offloading the execution to another script in the background and immediately close the input, output and error streams in order to let Xcode and xcodebuild finish cleanly. Create the following launcher script and invoke it from your post-scheme action as follows launcher command-that-parses-the-log-here:

   #!/bin/sh
   
   # The first argument is the directory of the executable you want to run.
   # The following arguments are directly forwarded to the executable.
   # We execute the command in the background and immediately close the input, output
   # and error streams in order to let Xcode and xcodebuild finish cleanly.
   # This is done to prevent Xcode and xcodebuild being stuck in waiting for all
   # subprocesses to end before exiting.
   executable=$1
   shift;
   $executable "$@" <&- >&- 2>&- &
   

4. The post-scheme action is not executed in case the build fails. An undocumented feature in Xcode allows you to execute it even in this case. Set the attribute runPostActionsOnFailure to YES in your scheme’s BuildAction as follows:

   <BuildAction buildImplicitDependencies='YES' parallelizeBuildables='YES' runPostActionsOnFailure='YES'>
   

Log Types

Build Logs

The xcactivitylog files are created by Xcode/xcodebuild a few seconds after a build completes. The log is placed in the DerivedData/YourProjectName-UUID/Logs/Build directory. It is a binary file in the SLF format compressed with gzip.

In the same directory, you will find a LogStoreManifest.plist file with the list of xcactivitylog files generated for the project. This file can be monitored in order to get notified every time a new log is ready.

Test Logs

The test logs are created inside the DerivedData/YourProjectName-UUID/Logs/Test directory. Xcode and xcodebuild create different logs. You can find a good description about which ones are created in this blog post.

Features

Dump Command

Dumps the whole content of an xcactivitylog file as JSON document. You can use this command if you want to have a raw but easy to parse representation of a log.

Examples:

xclogparser dump --file path/to/log.xcactivitylog --output activity.json
xclogparser dump --project MyProject --output activity.json --redacted

An example output has been omitted for brevity since it can contain a lot of information regarding a build.

Parse Command

Parses the build information from a xcactivitylog and converts it into different representations such as a JSON file, flat JSON file, summary JSON file, issues JSON file, Chrome Tracer file or a static HTML page.

This command supports parsing additional data if some flags are passed to Xcode/xcodebuild:

1. swiftc reported compilation times. For using that feature, you need to build your project with the options -Xfrontend -debug-time-expression-type-checking and -Xfrontend -debug-time-function-bodies.
2. ld64’s statistics output. The statistics info can be generated by adding -Xlinker -print_statistics to Xcode’s “Other Linker Flags” and it’s useful for tracking linking time regression.
3. Clang’s time trace data. When the -ftime-trace flag is specified, clang will generate a json tracing file for each translation unit and XCLogParser will collect them and add its data to the parser output.

Examples:

xclogparser parse --project MyApp --reporter json --output build.json
xclogparser parse --file /path/to/log.xcactivitylog --reporter chromeTracer
xclogparser parse --workspace /path/to/MyApp.xcworkspace --derived_data /path/to/custom/DerivedData --reporter html --redacted

Example output available in the reporters section.

Manifest Command

Outputs the contents of LogStoreManifest.plist which lists all the xcactivitylog files generated for the project as JSON.

Example:

xclogparser manifest --project MyApp

Example output:

{
  "scheme" : "MyApp",
  "timestampEnd" : 1548337458,
  "fileName" : "D6539DED-8AC8-4508-9841-46606D0C794A.xcactivitylog",
  "title" : "Build MyApp",
  "duration" : 46,
  "timestampStart" : 1548337412,
  "uniqueIdentifier" : "D6539DED-8AC8-4508-9841-46606D0C794A",
  "type" : "xcode"
}

Reporters

The parse command has different types of reporters built-in that can represent and visualize the data of the logs:

• JSON
• Flat JSON
• Summary JSON
• Chrome Tracer
• Issues
• HTML

JSON Reporter

This reporter parses the log and outputs it as JSON. It contains information about the duration of each step in the build, along other metadata and interesting information such as errors and warnings.

Example:

xclogparser parse --project MyApp --reporter json

{
    "detailStepType" : "swiftCompilation",
    "startTimestamp" : 1545143336.649699,
    "endTimestamp" : 1545143336.649699,
    "schema" : "MyApp",
    "domain" : "com.apple.dt.IDE.BuildLogSection",
    "parentIdentifier" : "095709ba230e4eda80ab43be3b68f99c_1545299644.4805899_20",
    "endDate" : "2018-12-18T14:28:56.650000+0000",
    "title" : "Compile \/Users\/<redacted>\/projects\/MyApp\/Libraries\/Utilities\/Sources\/Disposables\/Cancelable.swift",
    "identifier" : "095709ba230e4eda80ab43be3b68f99c_1545299644.4805899_185",
    "signature" : "CompileSwift normal x86_64 \/Users\/<redacted>\/MyApp\/Libraries\/Utilities\/Sources\/Disposables\/Cancelable.swift",
    "type" : "detail",
    "buildStatus" : "succeeded",
    "subSteps" : [

    ],
    "startDate" : "2018-12-18T14:28:56.650000+0000",
    "buildIdentifier" : "095709ba230e4eda80ab43be3b68f99c_1545299644.4805899",
    "machineName" : "095709ba230e4eda80ab43be3b68f99c",
    "duration" : 5.5941859483718872,
    "errors" : "",
    "warnings" : "",
    "errorCount" : 0,
    "warningCount" : 0,
    "errors" : [],
    "warnings" : [],
    "swiftFunctionTimes" : [
      {
        "durationMS" : 0.08,
        "occurrences" : 5,
        "startingColumn" : 36,
        "startingLine" : 48,
        "file" : "file:\/\/\/Users\/<redacted>\/MyApp\/Libraries\/Utilities\/Sources\/Disposables\/Cancelable.swift",
        "signature" : "getter description"
      }
    ],
    "swiftTypeCheckTimes" : [
      {
        "durationMS" : 0.5,
        "occurrences" : 2,
        "startingColumn" : 16,
        "startingLine" : 9,
        "file" : "file:\/\/\/Users\/<redacted>\/MyApp\/Libraries\/Utilities\/Sources\/Disposables\/Cancelable.swift",
      }
    ]
}

For more information regarding each field, check out the JSON format documentation.

FlatJson Reporter

Parses the log as an array of JSON objects, with no nested steps (the field subSteps is always empty). Useful to dump the data into a database so it’s easier to analyze.

The format of the JSON objects in the array is the same to the one used in the json reporter.

Example:

xclogparser parse --file path/to/log.xcactivitylog --reporter flatJson

[
  {
    "parentIdentifier" : "",
    "title" : "Build MobiusCore",
    "warningCount" : 0,
    "duration" : 0,
    "startTimestamp" : 1558590748,
    "signature" : "Build MobiusCore",
    "endDate" : "2019-05-23T05:52:28.274000Z",
    "errorCount" : 0,
    "domain" : "Xcode.IDEActivityLogDomainType.BuildLog",
    "type" : "main",
    "identifier" : "68a2bbd0048a454d91b3734b5d5dc45e_1558640253_1",
    "buildStatus" : "succeeded",
    "schema" : "MobiusCore",
    "subSteps" : [

    ],
    "endTimestamp" : 1558590748,
    "architecture" : "",
    "machineName" : "68a2bbd0048a454d91b3734b5d5dc45e",
    "buildIdentifier" : "68a2bbd0048a454d91b3734b5d5dc45e_1558640253",
    "startDate" : "2019-05-23T05:52:28.244000Z",
    "documentURL" : "",
    "detailStepType" : "none"
  },
  {
    "parentIdentifier" : "68a2bbd0048a454d91b3734b5d5dc45e_1558640253_1",
    "title" : "Prepare build",
    "warningCount" : 0,
    "duration" : 0,
    "startTimestamp" : 1558590748,
    "signature" : "Prepare build",
    "endDate" : "2019-05-23T05:52:28.261000Z",
    "errorCount" : 0,
    "domain" : "Xcode.IDEActivityLogDomainType.XCBuild.Preparation",
    "type" : "target",
    "identifier" : "68a2bbd0048a454d91b3734b5d5dc45e_1558640253_2",
    "buildStatus" : "succeeded",
    "schema" : "MobiusCore",
    "subSteps" : [

    ],
    "endTimestamp" : 1558590748,
    "architecture" : "",
    "machineName" : "68a2bbd0048a454d91b3734b5d5dc45e",
    "buildIdentifier" : "68a2bbd0048a454d91b3734b5d5dc45e_1558640253",
    "startDate" : "2019-05-23T05:52:28.254000Z",
    "documentURL" : "",
    "detailStepType" : "none"
  },{
    "parentIdentifier" : "68a2bbd0048a454d91b3734b5d5dc45e_1558640253_1",
    "title" : "Build target MobiusCore",
    "warningCount" : 0,
    "duration" : 4,
    "startTimestamp" : 1558590708,
    "signature" : "MobiusCore-fmrwijcuutzbrmbgantlsfqxegcg",
    "endDate" : "2019-05-23T05:51:51.890000Z",
    "errorCount" : 0,
    "domain" : "Xcode.IDEActivityLogDomainType.target.product-type.framework",
    "type" : "target",
    "identifier" : "68a2bbd0048a454d91b3734b5d5dc45e_1558640253_3",
    "buildStatus" : "succeeded",
    "schema" : "MobiusCore",
    "subSteps" : [

    ],
    "endTimestamp" : 1558590712,
    "architecture" : "",
    "machineName" : "68a2bbd0048a454d91b3734b5d5dc45e",
    "buildIdentifier" : "68a2bbd0048a454d91b3734b5d5dc45e_1558640253",
    "startDate" : "2019-05-23T05:51:48.206000Z",
    "documentURL" : "",
    "detailStepType" : "none"
  },
  ...
]

For more information regarding each field, check out the JSON format documentation.

SummaryJson Reporter

Parses the log as a JSON object, with no nested steps (the field subSteps is always empty). Useful to get a high level summary of the build.

Example:

xclogparser parse --file path/to/log.xcactivitylog --reporter summaryJson

  {
    "parentIdentifier" : "",
    "title" : "Build MobiusCore",
    "warningCount" : 0,
    "duration" : 0,
    "startTimestamp" : 1558590748,
    "signature" : "Build MobiusCore",
    "endDate" : "2019-05-23T05:52:28.274000Z",
    "errorCount" : 0,
    "domain" : "Xcode.IDEActivityLogDomainType.BuildLog",
    "type" : "main",
    "identifier" : "68a2bbd0048a454d91b3734b5d5dc45e_1558640253_1",
    "buildStatus" : "succeeded",
    "schema" : "MobiusCore",
    "subSteps" : [

    ],
    "endTimestamp" : 1558590748,
    "architecture" : "",
    "machineName" : "68a2bbd0048a454d91b3734b5d5dc45e",
    "buildIdentifier" : "68a2bbd0048a454d91b3734b5d5dc45e_1558640253",
    "startDate" : "2019-05-23T05:52:28.244000Z",
    "documentURL" : "",
    "detailStepType" : "none"
  }

For more information regarding each field, check out the JSON format documentation.

ChromeTracer Reporter

Parses the xcactivitylog as an array of JSON objects in the format used by the Chrome tracer. You can use this JSON to visualize the build times in the Chrome tracing tool inside Chrome: chrome://tracing.

Example:

xclogparser parse --file path/to/log.xcactivitylog --reporter chromeTracer

Example Output

Issues Reporter

Outputs the list of Errors and Warnings found in the log as a JSON document. Useful when you only want to check the issues found while building.

Example:

xclogparser parse --file path/to/log.xcactivitylog --reporter issues

```json
{
  "errors" : [
    {
      "characterRangeStart" : 0,
      "startingColumnNumber" : 5,
      "endingColumnNumber" : 30,
      "characterRangeEnd" : 18446744073709551615,
      "title" : "use of undeclared type 'AType'",
      "endingLineNumber" : 10,
      "type" : "swiftError",
      "documentURL" : "file:\/\/\/MyProject\/MyFile.swift",
      "startingLineNumber" : 10,
      "severity" : 1
      "detail": "\/MyProject\/MyFile.swift:10:5: error: use of undeclared type 'AType'\r    func doSomething(completion: @escaping () -> AType) -> void) {\r^~~~\r"
    }
  ],
  "warnings" : [
    {
      "characterRangeStart" : 0,
      "startingColumnNumber" : 5,
      "endingColumnNumber" : 30,
      "characterRangeEnd" : 18446744073709551615,
      "title" : "Warning",
      "endingLineNumber" : 10,
      "type" : "swiftWarning",
      "documentURL" : "file:\/\/\/MyProject\/MyFile.swift",
      "startingLineNumber" : 10,
      "severity" : 1
    }
  ]
}
```

HTML Reporter

Generates an HTML report to visualize build times per module and file, along with warning and error messages.

Example:

xclogparser parse --file path/to/log.xcactivitylog --reporter html --output build/reports

Example Output

Requirements and Compatibility

Status

XCLogParser is currently in alpha status. We are using it internally and tested it on various projects, but we need the help from the community to test and improve it with more iOS and Mac applications.

Development and Contributing

MacOS:

1. Clone the repo with git clone [email protected]:MobileNativeFoundation/XCLogParser.git.
2. Run rake gen_resources to generate a static resource Swift file that is needed to compile the app.
3. Run swift package generate-xcodeproj to generate a Xcode project (or use any text editor).
4. Run tests in Xcode directly (CMD + U) or using rake test.
5. Create issue and discuss a possible solution or improvement.
6. Create a PR.

Linux:

1. A Dockerfile is provided, you can create an image with the tag xlogparser: docker build --tag xclogparser .
2. To compile the app in Linux, just run the shell script: ./run-in-docker.sh

If you find a bug or you would like to propose an improvement, you’re welcome to create an issue.

Release

1. Make sure version set in Version.swift is updated
2. Create new release tag in GitHub with a tag format like vx.x.x. Provide release title and description.
3. Build release artifacts:
   1. for macOS, build an artifact using DEVELOPER_DIR=<path_to_xcode_version> rake archive. Use Xcode version matching with Requirements section.
   2. for Linux, run ./build_release_in_docker.sh
4. Upload release artifacts to the release version summary:
   1. for macOS, upload zip file placed in releases/XCLogParser-x.x.x.zip
   2. for Linux, update current version in the filename and upload releases/linux/XCLogParser-x.x.x-Linux.zip

Code of Conduct

This project adheres to the Open Code of Conduct. By participating, you are expected to honor this code.