appmap-agent-js
is a JavaScript agent for recording
AppMaps of your code. “AppMap” is a data
format which records code structure (modules, classes, and methods), code
execution events (function calls and returns), and code metadata (repo name,
repo URL, commit SHA, labels, etc). It’s more granular than a performance
profile, but it’s less granular than a full debug trace. It’s designed to be
optimal for understanding the design intent and structure of code and key data
flows.
There are several ways to record AppMaps of your JavaScript program using the appmap
agent:
Once you have made a recording, there are two ways to view automatically generated diagrams of the AppMaps.
The first option is to load the diagrams directly in your IDE, using the AppMap for WebStorm or other JetBrains IDE or AppMap for Visual Studio Code.
The second option is to upload them to app.land using the AppMap CLI.
AppMap for JavaScript is currently in Open Beta. Requirements:
Using a framework we don't support yet? Let us know in Slack!
Run this command in your Node.js project folder (where package.json
is located):
npx @appland/appmap install
You will be guided through a series of steps for installing and configuring the agent.
To use remote recording, and view and interact with recorded AppMaps, we recommend installing the AppMap extension for popular code editors:
When you run your program, the agent reads configuration settings from appmap.yml
.
The install
command creates a default appmap.yml
file by scanning the project directories.
We recommend that you review the generated appmap.yml
file and confirm your application name
and a list of directories that will be recorded.
Here’s a sample configuration file for a typical JavaScript project:
# 'name' should generally be the same as the code repo name.
name: MyApp
packages:
- path: src/server/controllers
- path: src/server/data
- path: src/server/models
- path: src/server/routes
- path: src/server/lib
shallow: true
exclude:
- src/server/lib/util
packages
Each entry in the packages
list is a YAML object which has the following keys:
path
specified in the same package entry.true
, only the first function call entry into a package will be recorded. Subsequent function calls within
the same package are not recorded unless code execution leaves the package and re-enters it. Default: false
.When running test cases with the agent attached to the JavaScript engine, a new AppMap file will be created for each unique test case.
appmap-agent-js
with the mocha
command and its parameters following the --
delimiter.
For example:
npx appmap-agent-js -- mocha test/**/*.ts
appmap-agent-js
will run the tests. When the tests are complete, the AppMaps will be stored
in the default output directory tmp/appmap/mocha
.appmap-agent-js
supports the AppMap remote recording API.
This functionality is provided by the AppMap agent. It will hook an existing HTTP engine,
serving HTTP requests to toggle recording on and off.
appmap-agent-js
with the application-starting command and its parameters following the --
delimiter. For example:
npx appmap-agent-js -- node app/main.js --param1 hello --param2=world
appmap-agent-js
will start the app and inject itself in its http stack. It will listen for remote recording requests on all http ports of the application.appmap.yml
appmap-agent-js
parametersThe most frequently used appmap-agent-js
parameters are:
--recorder=[mocha|remote|process]
: process recorder
mocha
if the the command contains mocha
remote
in all other casesmocha
recorder records AppMaps from test cases automaticallyremote
recorder has to be started and stopped manually with http requestsprocess
recorder records entire processes automatically, from start to finish
process
recorder can be excessively large and noisy.--command="_start command_"
: alternate method of specifying the app- or tests-starting command, wrapped in quotes--log-level=[debug|info|warning|error]
: defaults to info
--log-file=_file_
: defaults to stderr
--output-dir=_directory_
: location of recorded AppMap files, default is tmp/appmap
or tmp/appmap/mocha
--help
prints out help message to stdout--version
installed versionnpx appmap-agent-js --recorder=mocha --command="mocha test/**/*.ts" --log-level=error
APPMAP_CONFIGURATION_PATH
Path to the appmap.yml
config file. Default:
appmap.yml
APPMAP_REPOSITORY_DIRECTORY
Path to the project’s local git folder. Default: .Recorded AppMap are saved as .appmap.json
files in the project folders (default location: tmp/appmap
.)
Follow the documentation for your IDE to open the recorded .appmap.json
files:
https://github.com/applandinc/appmap-agent-js