Command line interface (CLI)

• Command line interface (CLI)
  • Overview
  • Installation
  • Usage
    • Inspect
    • Interactive mode
      • (h)ome
      • (p)rint
      • (f)ilter
      • (u)ndo filter
      • (r)eset filters
      • (q)uit
    • Openapi
    • Prune
  • GitHub repository

Overview

The AppMap CLI @appland/appmap provides utility commands for working with AppMaps.

Installation

The AppMap Client CLI is written in Node.JS, so you install and manage this CLI using yarn or npm:

$ yarn add --dev @appland/appmap

Usage

Run @appland/appmap with npx or yarn run:

$ npx @appland/appmap --help

or

$ yarn run appmap --help

Inspect

Search AppMaps for references to a code object (package, function, class, query, route, etc) and print available event info.

$ npx @appland/appmap inspect --help

  appmap inspect <code-object>

  Positionals:

    code-object  identifies the code-object to inspect                  [required]

  Options:
        --version      Show version number                               [boolean]
    -v, --verbose      Run with verbose logging                          [boolean]
        --help         Show help                                         [boolean]
        --appmap-dir   directory to recursively inspect for AppMaps
                                                          [default: "tmp/appmap"]
    -i, --interactive  interact with the output via CLI                  [boolean]

You can use this command to search and display events and associated data from across all the AppMaps in a directory (recursively explored).

The code-object argument is a required argument, composed of a type and identifier. The inspect command will find all events that match this code object across all the AppMaps. Whether an event matches the code-object argument is defined as follows:

Examples of supported search syntax:

• function:my/package/My::Class#instance_method
• function:my/package/My::Class.static_method
• class:my/package/My::Class
• package:my/package
• table:table_name
• database:
• route:REQUEST_METHOD /route/:id (HTTP request method followed by normalized path)
• query:SELECT * FROM tables WHERE some_column = ? (normalized SQL)

Interactive mode

With the --interactive option, the results are presented in table form, and you can refine and drill into the data using the command line.

$ npx @appland/appmap inspect --interactive

Without the --interactive option, all matching results are printed as JSON. This mode is suitable for searching AppMaps and printing results that can be piped into other scripts (e.g. using jq) for further processing.

Interactive mode arguments

(h)ome

The home screen is displayed at the beginning of interactive mode. The (h)ome command will generally return you to the home screen, when you are in other parts of the app.

The home screen presents the following data:

On the home screen, a field is displayed if there are only a small number of distinct values. Otherwise, the number of distinct values is shown, and you can use the (p)rint command to see the full details.

(p)rint

Prints the full details of a numbered field. Unlike the (h)ome view, which will summarize fields with many values, the (p)rint command will always print out all the distinct values of a field (even if there are thousands of them…).

(f)ilter

Applies a filter to the result set. You can use this command to reduce the number of search matches that are displayed, both on the (h)ome screen and in the (p)rint views.

When you choose the (f)ilter command, you’re first prompted to select which field you want to choose the filter value from. For example, you may see a table that includes (2) Return values (3) HTTP server requests (6) Callers. On choosing one of these fields, you are then prompted to select a value. The values will be the same as if you chose to (p)rint the selected field. Each field value is numbered; enter the number of the field value to activate it as a filter.

The result set is then recomputed, matching only events that match BOTH the main code-object argument that you initially provided to the search command, AND the filter.

For example, if you searched for table:users and then filtered by request:GET /user 200, the search would match every query that accesses the users table within an HTTP GET request to /user that returns status code 200.

If you apply another filter, then BOTH filter conditions must match each result.

(u)ndo filter

Un-apply the most recently applied filter.

(r)eset filters

Remove all filters.

(q)uit

Quit the interactive program.

Openapi

$ npx @appland/appmap openapi --help

  appmap openapi

  Generate OpenAPI from AppMaps in a directory

  Options:
        --version           Show version number                          [boolean]
    -v, --verbose           Run with verbose logging                     [boolean]
        --help              Show help                                    [boolean]
        --appmap-dir        directory to recursively inspect for AppMaps
                                                          [default: "tmp/appmap"]
    -o, --output-file       output file name
        --openapi-template  template YAML; generated content will be placed in the
                            paths and components sections
        --openapi-title     info/title field of the OpenAPI document
        --openapi-version   info/version field of the OpenAPI document

Use this command to generate OpenAPI documentation from all AppMaps in a directory (recursively explored).

openapi ships with a default yml template but you can use a custom template if you specify its file with the optional --openapi-template parameter.

The --openapi-title and --openapi-version parameters override the values of the info/title and info/version properties in the generated document.

Prune

$ npx @appland/appmap prune --help

  appmap prune <file> <size>

  Prune an appmap file down to the given size

  Positionals:
    file  AppMap to prune                                               [required]
    size  Prune input file to this size                                 [required]

  Options:
        --version     Show version number                                [boolean]
    -v, --verbose     Run with verbose logging                           [boolean]
        --help        Show help                                          [boolean]
    -o, --output-dir  Specifies the output directory. Pruned files will be written
                      here.                                [string] [default: "."]

Use this command to remove events from an AppMap, to make it easier to understand.

Pruning works by finding the most repetitive calls within a given “chunk” and removing events associated with those calls. A chunk is defined as a group of logic, consisting of one or more full call stacks. Boundaries of these chunks are created around application entrypoints such as inbound HTTP request.

An example list of chunks is provided below:

  HTTP request - GET /user
  Background thread processing
  HTTP request - PUT /user
  Background thread processing
  HTTP request - GET /

For each chunk, aggregate the total number of unique events. Starting from the most repetitive event type, remove instances of that event until the size of the chunk (in byte) is less than:

  requested size / total event array size * starting chunk size

In essence, we’re calculating a unique exclusion list for each chunk. This prevents an excessively noisy or repetitive call stack in one area of execution from affecting the results of unrelated areas of execution.

Non-application events such as HTTP requests and SQL queries will always be retained. This means that the end result can never be smaller than the total size of these events combined.

GitHub repository

https://github.com/getappmap/appmap-js/tree/main/packages/cli