vimspector-ref.txt

*vimspector-ref*

===============================================================================
Contents ~

 1. Introduction                                  |vimspector-ref-introduction|
 2. title: Configuration                   |vimspector-ref-title-configuration|
 3. Concepts                                          |vimspector-ref-concepts|
  1. Debug adapter configuration   |vimspector-ref-debug-adapter-configuration|
  2. Debug profile configuration   |vimspector-ref-debug-profile-configuration|
  3. Replacements and variables         |vimspector-ref-replacements-variables|
   1. The splat operator                        |vimspector-ref-splat-operator|
   2. Default values                            |vimspector-ref-default-values|
   3. Coercing Types                            |vimspector-ref-coercing-types|
 4. Configuration Format                  |vimspector-ref-configuration-format|
 5. Files and locations                        |vimspector-ref-files-locations|
 6. Adapter configurations              |vimspector-ref-adapter-configurations|
 7. Debug configurations                  |vimspector-ref-debug-configurations|
  1. Configuration selection           |vimspector-ref-configuration-selection|
   1. Specifying a default configuration |vimspector-ref-specifying-default-configuration|
   2. Preventing automatic selection |vimspector-ref-preventing-automatic-selection|
  2. Exception Breakpoints               |vimspector-ref-exception-breakpoints|
 8. Predefined Variables                  |vimspector-ref-predefined-variables|
 9. Remote Debugging Support          |vimspector-ref-remote-debugging-support|
  1. Python (debugpy) Example                   |vimspector-ref-python-example|
  2. C-family (gdbserver) Example             |vimspector-ref-c-family-example|
  3. Docker Example                             |vimspector-ref-docker-example|
 10. Appendix: Configuration file format |vimspector-ref-appendix-configuration-file-format|
 11. Appendix: Editor configuration |vimspector-ref-appendix-editor-configuration|
 12. References                                     |vimspector-ref-references|

===============================================================================
                                                  *vimspector-ref-introduction*
Introduction ~

===============================================================================
                                           *vimspector-ref-title-configuration*
title: Configuration ~

This document defines the supported format for project and adapter
configuration for Vimspector.

- Concepts

  - Debug adapter configuration
  - Debug profile configuration
  - Replacements and variables
  - The splat operator
  - Default values
  - Coercing Types

- Configuration Format
- Files and locations
- Adapter configurations
- Debug configurations

  - Configuration selection

    - Specifying a default configuration
    - Preventing automatic selection

  - Exception Breakpoints

- Predefined Variables
- Remote Debugging Support

  - Python (debugpy) Example
  - C-family (gdbserver) Example
  - Docker Example

- Appendix: Configuration file format
- Appendix: Editor configuration

===============================================================================
                                                      *vimspector-ref-concepts*
Concepts ~

As Vimspector supports debugging arbitrary projects, you need to tell it a few
details about what you want to debug, and how to go about doing that.

In order to debug things, Vimspector requires a Debug Adapter which bridges
between Vimspector and the actual debugger tool. Vimspector can be used with
any debug adapter that implements the Debug Adapter Protocol [1].

For each debugging session, you provide a _debug configuration_ which includes
things like:

- The debug adapter to use (and possibly how to launch and configure it).
- How to connect to the remote host, if remote debugging.
- How to launch or attach to your process.

Along with optional additional configuration for things like:

- Exception breakpoints

-------------------------------------------------------------------------------
                                   *vimspector-ref-debug-adapter-configuration*
Debug adapter configuration ~

The adapter to use for a particular debug session can be specified inline
within the _debug configuration_, but more usually the debug adapter is defined
separately and just referenced from the _debug configuration_.

The adapter configuration includes things like:

- How to launch or connect to the debug adapter
- How to configure it for PID attachment
- How to set up remote debugging, such as how to launch the process remotely
  (for example, under 'gdbserver', 'ptvsd', etc.)

-------------------------------------------------------------------------------
                                   *vimspector-ref-debug-profile-configuration*
Debug profile configuration ~

Projects can have many different debug profiles. For example you might have all
of the following, for a given source tree:

- Remotely launch c++ the process, and break on 'main'
- Locally Python test and break exception
- Remotely attach to a c++ process
- Locally launch a bash script
- Attach to a JVM listening on a port

Each of these represents a different use case and a different _debug
configuration_. As mentioned above, a _debug configuration_ is essentially:

- The adapter to use

- The type of session (launch or attach), and whether or not to do it
  remotely

- The configuration to pass to the adapter in order to launch or attach to
  the process.

The bulk of the configuration is the last of these, which comprises
adapter-specific options, as the Debug Adapter Protocol does not specify any
standard for launch or attach configuration.

-------------------------------------------------------------------------------
                                        *vimspector-ref-replacements-variables*
Replacements and variables ~

Vimspector _debug configuration_ is intended to be as general as possible, and
to be committed to source control so that debugging your applications becomes a
simple, quick and pain-free habit (e.g. answering questions like "what happens
if..." with "just hit F5 and step through!").

Therefore it's important to abstract certain details, like runtime and
build-time paths, and to parameterise the _debug configuration_. Vimspector
provides a simple mechanism to do this with '${replacement}' style
replacements.

The values available within the '${...}' are defined below, but in summary the
following are supported:

- Environment variables, such as '${PATH}'
- Predefined variables, such as '${workspaceRoot}', '${file}' etc.
- Configuration-defined variables, either provided by the adapter
  configuration or debug configuration, or from running a simple shell
  command.
- Anything else you like - the user will be asked to provide a value.

If the latter 2 are confusing, for now, suffice to say that they are how
Vimspector allows parameterisation of debug sessions. The [Vimspector
website][website-getting-started] has a good example of where this sort of
thing is useful: accepting the name of a test to run.

But for now, consider the following example snippet:
>
  {
    "configurations": {
      "example-debug-configuration": {
        // This is a single-line comment  explaining the purpose
        "adapter": "example-adapter-name",
        "variables": {
          "SecretToken": { // Variables should start with upper-case letters
            "shell" : [ "cat", "${HOME}/.secret_token" ]
          }
        },
        "configuration": {
          "request": "launch" /* or it could be "attach" */,
          "program": [
            "${fileBasenameNoExtension}",
            "-c", "configuration_file.cfg",
            "-u", "${USER}",
            "--test-identifier", "${TestIdentifier}",
            "--secret-token", "${SecretToken}"
          ]
        },
        "breakpoints": {
          "exception": {
            "caught": "",
            "uncaught": "Y"
          }
        }
      }
    }
  }
<
In this (fictitious) example the 'program' launch configuration item contains
the following variable substitutions:

- '${fileBasenameNoExtension}' - this is a Predefined Variable, set by
  Vimspector to the base name of the file that's opened in Vim, with its
  extension removed ('/path/to/xyz.cc' -> 'xyz').

- '${USER}' - this refers to the Environment Variable 'USER'.

- '${TestIdentifier}' - this variable is not defined, so the user is asked to
  provide a value interactively when starting debugging. Vimspector remembers
  what they said and provides it as the default should they debug again.

- '${SecretToken}' - this variable is provided by the configuration's
  'variables' block. Its value is taken from the 'strip''d result of running
  the shell command. Note these variables can be supplied by both the debug
  and adapter configurations and can be either static strings or shell
  commands.

-------------------------------------------------------------------------------
                                                *vimspector-ref-splat-operator*
The splat operator ~

Often we want to create a single '.vimspector.json' entry which encompasses
many use cases, as it is tedious to write every use case/start up option in
JSON. This is why we have the replacement variables after all.

Frequently debug adapters request command arguments as a JSON array, for
example:
>
  "args": [ "one", "two three", "four" ],
<
To help with this sort of case, Vimspector supports a 'splat' operator for
replacement variables operating within lists. The syntax is: '"*${var}', which
means roughly "splice the contents of '${var}' into the list at this position".
'${var}' is parsed like a shell command (using python's 'shlex' parser) and
each word is added as a list item.

For example:
>
  "args": [ "*${CommandLineArgs}" ]
<
This would:

- Ask the user to provide the variable 'CommandLineArgs'. Let's say they
  entered 'one "two three" four'
- Split 'CommandLineArgs' like shell arguments: 'one', 'two three' and 'four'
- Set 'args' in the settings dict to: '[ "one", "two three", "four" ]'

You can also combine with static values:
>
  "args": [ "First", "*${CommandLineArgs}", "Last" ]
<
This would yield the intuitive result: '[ "First", "one", "two three", "four",
"Last" ]'

-------------------------------------------------------------------------------
                                                *vimspector-ref-default-values*
Default values ~

You can specify replacements with default values. In this case if the user has
not specified a value, they are prompted but with the default value
pre-populated, allowing them to just press return to accept the default.

The syntax is '${variableName:default value}'. The default value can contain
any character, but to include a '}' you must escape it with a backslash. To
include a backslash in the JSON you must write '\\', as in:
>
  { "key": "${value:default {\\} stuff}" }
<
The default value can also be a replacement variable. However, this _must_ be a
variable that's already defined, such as one of the predefined variables, or
one specified in a 'variables' block. In order to reference them, you _must_
use '${var}' syntax and you _must_ escape the closing '}'. For example, the is
a common and useful case:
>
  {
    "configuration": {
      "program": "${script:${file\\}}"
    }
  }
<
This will prompt the user to specify 'script', but it will default to the path
to the current file.

-------------------------------------------------------------------------------
                                                *vimspector-ref-coercing-types*
Coercing Types ~

Sometimes, you want to provide an option for a boolean parameter, or want to
allow the user to specify more than just strings. Vimspector allows you to do
this, ensuring that the resulting JSON is valid. This is done by interpreting a
value as a JSON string and substituting the resulting JSON value in its place.

This is easier to explain with an example. Let's say we want to offer the
ability to break on entry, as an option for the user. The launch configuration
requires 'stopOnEntry' to be a bool. This doesn't work:
>
  "stopOnEntry": "${StopOnEntry}"
<
The reason is that if the user types 'true', the resulting object is:
>
  "stopOnEntry": "true"
<
The problem being that is a string, not a boolean. So Vimspector allows you to
re-interpret the string as a JSON value and use that instead. To do this, add
'#json' to the key's name. You can even add a default, like this:
>
  "stopOnEntry#json": "${stopOnEntry:true}"
<
If the user accepts the default, the resulting string '"true"' is coerced to a
JSON value 'true', and the suffix is stripped fom the key, resulting in the
following:
>
  "stopOnEntry": true
<
Which is what we need.

If you happen to have a key that already ends in '#json' (unlikely!), then you
can force Vimspector to treat the value as a string by appending '#s', as in:
>
  "unlikelyKeyName#json#s": "this is a string, not JSON data"
<
**_Advanced usage:_**

The most common usage for this is for number and bool types, but it works for
objects too. If you want to be able to specify a whole object (e.g. a whole
'env' dict), then you can do that too:
>
  "env#json": "${Environment:{\\}}"
<
The default value here is '{}' (note the '}' must be escaped!). The user can
then enter something like '{ "MYVAR": "MyValue", "OTHER": "Other" }' and the
resulting object would be:
>
  "env": {
    "MYVAR": "MyValue",
    "OTHER": "Other"
  }
<
It also works for lists, though the splat operator is usually more convenient
for that.

===============================================================================
                                          *vimspector-ref-configuration-format*
Configuration Format ~

All Vimspector configuration is defined in a JSON object. The complete
specification of this object is available in the JSON Schema [2], but the basic
format for the configuration object is:
>
  {
    "adapters": { <object mapping name to <adapter configuration> },
    "configurations": { <object mapping name to <debug configuration> }
  }
<
The 'adapters' key is actually optional, as '<adapter configuration>' can be
embedded within '<debug configuration>', though this is not recommended usage.

===============================================================================
                                               *vimspector-ref-files-locations*
Files and locations ~

The above configuration object is constructed from a number of configuration
files, by merging objects in a specified order.

In a minimal sense, the only file required is a '.vimspector.json' file in the
root of your project which defines the full configuration object [2], but it is
usually useful to split the 'adapters' configuration into a separate file (or
indeed one file per debug adapter).

The following sections describe the files that are read and use the following
abbreviations:

- '<vimspector home>' means the path to the Vimspector installation (such as
  '$HOME/.vim/pack/vimspector/start/vimspector')

- '<OS>' is either 'macos', 'linux' or 'windows' depending on the host
  operating system.

- '<filetype>' is the Vim filetype. Where multiple filetypes are in effect,
  typically all filetypes are checked.

===============================================================================
                                        *vimspector-ref-adapter-configurations*
Adapter configurations ~

Vimspector reads a series of files to build the 'adapters' object. The
'adapters' objects are merged in such a way that a definition for an adapter
named 'example-adapter' in a later file _completely replaces_ a previous
definition.

- '<vimspector home>/gadgets/<OS>/.gadgets.json' - the file written by
  'install_gadget.py' and not usually edited by users.

- '<vimspector home>/gadgets/<OS>/.gadgets.d/*.json' (sorted alphabetically).
  These files are user-supplied and override the above.

- The first such '.gadgets.json' file found in all parent directories of the
  file open in Vim.

- The '.vimspector.json' and any filetype-specific configurations (see below)

In all cases, the required format is:
>
  {
    "$schema": "https://puremourning.github.io/vimspector/schema/gadgets.schema.json#",
    "adapters": {
      "<adapter name>": {
        <adapter configuration>
      }
    }
  }
<
Each adapters block can define any number of adapters. As mentioned, if the
same adapter name exists in multiple files, the last one read takes precedence
and _completely replaces_ the previous configuration. In particular that means
you can't just override one option, you have to override the whole block.

Adapter configurations are re-read at the start of each debug session.

The specification for the gadget object is defined in the [gadget schema][].

===============================================================================
                                          *vimspector-ref-debug-configurations*
Debug configurations ~

There are two locations for debug configurations for a project:

- '<vimspector home>/configurations/<OS>/<filetype>/*.json'
- '.vimspector.json' in the project source

Typically, the debug configurations are read from '.vimspector.json'. The file
is found (like '.gadgets.json' above) by recursively searching up the directory
hierarchy from the directory of the file open in Vim. The first file found is
read and no further searching is done.

Only a single '.vimspector.json' is read. If one is found, the location of this
file is used for '${workspaceRoot}' and other workspace-relative paths.

In addition, users can create filetype-specific configurations in the
Vimspector installation directory. This can be useful where the parameters for
the debug session for a particular filetype are always known in advance, or can
always be entered by the user. This allows for debugging to "just work" without
any modification to the project source (no need to add a '.vimspector.json').
In this case, the '${workspaceRoot}' and workspace-relative paths are
interpreted relative to the file open in Vim. This isn't ideal, but there is no
other obvious way to default this variable.

As with gadgets, any debug configurations appearing within '.vimspector.json'
override any that appear in the common configuration dir.

Debug configurations are re-read at the start of each debug session, so
modifications are picked up without any restarts of Vim.

The specification for the gadget object is defined in the schema [2], but a
typical example looks like this:
>
  {
    "$schema": "https://puremourning.github.io/vimspector/schema/vimspector.schema.json#",
    "configurations": {
      "<configuation name>": {
        "adapter": "<adapter name>",
        "configuration": {
          "request": "<launch or attach>",
          <debug configutation>
        }
      }
    }
  }
<
-------------------------------------------------------------------------------
                                       *vimspector-ref-configuration-selection*
Configuration selection ~

When starting debugging, you can specify which debug configuration to launch
with "call vimspector#LaunchWithSettings( #{ configuration: 'name here' } )".

Otherwise, if there's only one configuration found, Vimspector will use that
configuration, unless it contains a key '"autoselect": false'.

If multiple debug configurations are found, and no explicit configuration was
selected on Launch, the user is prompted to select a configuration, unless a
single debug configuration is found with a key '"default": true'.

-------------------------------------------------------------------------------
                              *vimspector-ref-specifying-default-configuration*
Specifying a default configuration ~

As noted, you can specify a default configuration with '"default": true':
>
  {
    "configurations": {
      "use this one": {
        "default": true,
        "adapter": " ... ",
        "configuation": {
          // ...
        }
      },
      "don't use this one": {
        // ...
      }
    }
  }
<
If multiple configurations are found with 'default' set to 'true', then the
user is prompted anyway.

-------------------------------------------------------------------------------
                                *vimspector-ref-preventing-automatic-selection*
Preventing automatic selection ~

If you don't want a configuration to be selected automatically, then set
'"autoselect": false'. This particularly useful for configurations in the
central (as opposed to project-local) directory. For example:
>
  "configurations": {
    "Don't use this by default!": {
      "autoselect": false,
      "adapter": " ... ",
      "configuation": {
        // ...
      }
    }
  }
<
Setting 'autoselect' to 'false' overrides setting 'default' to 'true'.

-------------------------------------------------------------------------------
                                         *vimspector-ref-exception-breakpoints*
Exception Breakpoints ~

Debug adapters have arbitrary configuration for exception breakpoints. Normally
this is presented as a series of question to the user on starting the debug
session. The question includes the name of the exception breakpoint option, the
default and the list of valid responses (usually 'Y' or 'N').

You can pre-configure the answers to these questions in the 'breakpoints'
section of the debug configuration. For each question, take the name provided
and configure the response 'exception' mapping in the 'breakpoints' mapping. If
the configured response is empty string, the debug adapter default will be
used.

Referring to the above example, the following tells the debug adapter to use
the default value for 'caught' exceptions and to break on 'uncaught' exception:
>
  {
    "configurations": {
      "example-debug-configuration": {
        "adapter": "example-adapter-name",
        "breakpoints": {
          "exception": {
            "caught": "",
            "uncaught": "Y"
          }
        },
        ...
<
The keys in the 'exception' mapping are what Vimspector includes in the prompt.
For example, when prompted with the following:
>
  cpp_throw: Break on C++: on throw (Y/N/default: Y)?
<
The exception breakpoint "type" is 'cpp_throw' and the default is 'Y'.

Similarly:
>
  cpp_catch: Break on C++: on catch (Y/N/default: N)?
<
The exception breakpoint "type" is 'cpp_catch' and the default is 'N'.

Use the following to set the values in configuration and not get asked:
>
  "configurations": {
    "example-debug-configuration": {
      "adapter": "example-adapter-name",
      "breakpoints": {
        "exception": {
          "cpp_throw": "Y",
          "cpp_catch": "Y"
        }
      },
<
To just accept the defaults for these exception breakpoint types, don't specify
a value, as in :
>
  "configurations": {
    "example-debug-configuration": {
      "adapter": "example-adapter-name",
      "breakpoints": {
        "exception": {
          "cpp_throw": "",
          "cpp_catch": ""
        }
      },
<
===============================================================================
                                          *vimspector-ref-predefined-variables*
Predefined Variables ~

The following variables are provided:

- '${dollar}' - has the value '$', can be used to enter a literal dollar
- '$$' - a literal dollar
- '${workspaceRoot}' - the path of the folder where '.vimspector.json' was
  found
- '${workspaceFolder}' - the path of the folder where '.vimspector.json' was
  found
- '${gadgetDir}' - path to the OS-specific gadget dir ('<vimspector
  home>/gadgets/<OS>')
- '${file}' - the current opened file
- '${relativeFile}' - the current opened file relative to 'workspaceRoot'
- '${fileBasename}' - the current opened file's 'basename'
- '${fileBasenameNoExtension}' - the current opened file's 'basename' with no
  file extension
- '${fileDirname}' - the current opened file's 'dirname'
- '${fileExtname}' - the current opened file's extension
- '${cwd}' - the current working directory of the active window on launch
- '${unusedLocalPort}' - an unused local TCP port

===============================================================================
                                      *vimspector-ref-remote-debugging-support*
Remote Debugging Support ~

Vimspector has in-built support for executing remote debuggers (such as
'gdbserver', 'debugpy', 'llvm-server' etc.). This is useful for environments
where the development is done on one host and the runtime is some other host,
account, container, etc.

In order for it to work, you have to set up paswordless SSH between the local
and remote machines/accounts. Then just tell Vimspector how to remotely launch
and/or attach to the app.

This is presented as examples with commentary, as it's a fairly advanced/niche
case. If you're not already familiar with remote debugging tools (such as
gdbserver) or not familiar with ssh or such, you might need to independently
research that.

Vimspector's tools are intended to automate your existing process for setting
this up rather than to offer batteries-included approach. Ultimately, all
Vimspector is going to do is run your commands over SSH, or docker, and
co-ordinate with the adapter.

-------------------------------------------------------------------------------
                                                *vimspector-ref-python-example*
Python (debugpy) Example ~

Here is some examples using the Vimspector built-in remote support (using SSH)
to remotely launch and attach a python application and connect to it using
debugpy.

The usage pattern is to hit '<F5>', enter 'host' (the host where your app
runs), 'account' (the account it runs under), and 'port' (a port that will be
opened on the remote host). Vimspector also supports exec'ing into Docker run
containers with 'container' (the container name or id your app is running in).
Vimspector then orchestrates the various tools to set you up.
>
  {
    "adapters": {
      "python-remote": {
        "port": "${port}",
        "host": "${host}",
        "launch": {
          "remote": {
            "host": "${host}",       // Remote host to ssh to (mandatory if not using container)
            "account": "${account}", // User to connect as (optional)
  
            // Optional.... Manual additional arguments for ssh
            // "ssh": {
            //   "args": [ "-o", "StrictHostKeyChecking=no" ]
            // },
  
            // Command to launch the debugee and attach the debugger; 
            // %CMD% replaced with the remote-cmdLine configured in the launch
            // configuration. (mandatory)
            "runCommand": [
              "python", "-m", "debugpy",
              "--listen", "0.0.0.0:${port}",
              "--wait-for-client",
              "%CMD%"
            ]
  
            // Optional alternative to runCommand (if you need to run multiple
            // commands)
            // "runCommands":  [
            //   [ /* first command */ ],
            //   [ /* second command */ ]
            // ]
  
          }
  
          // optional delay to wait after running runCommand(s). This is often
          // needed because of the way docker handles TCP, or if you're using some
          // wrapper (e.g. to start the JVM)
          // "delay": "1000m" // format as per :help sleep
        },
        "attach": {
          "remote": {
            "host": "${host}", // Remote host to ssh to (mandatory if not using container)
            "account": "${account}", // User to connect as (optional)
            // Command to get the PID of the process to attach  (mandatory)
            "pidCommand": [
              //
              // Remember taht you can use ${var} to ask for input. I use this to
              // call a custom command to returm the PID for a named service, so
              // here's an examle:
              //
              "/path/to/secret/script/GetPIDForService", "${ServiceName}"
            ],
  
            // Command to attach the debugger; %PID% replaced with output of
            // pidCommand above (mandatory)
            "attachCommand": [
              "python", "-m", "debugpy", "--listen", "0.0.0.0:${port}",
              "--pid", "%PID%"
            ]
  
            // Optional alternative to attachCommand (if you need to run multiple
            // commands)
            // "attachCommands":  [
            //   [ /* first command */ ],
            //   [ /* second command */ ]
            // ],
  
            // Optional.... useful with buggy gdbservers to kill -TRAP %PID%
            // "initCompleteCommand": [
            //   /* optional command to run after initialized */
            // ]
  
            // Optional.... Manual additional arguments for ssh
            // "ssh": {
            //   "args": [ "-o", "StrictHostKeyChecking=no" ]
            // },
          }
          // optional delay to wait after running runCommand(s). This is often
          // needed because of the way docker handles TCP, or if you're using some
          // wrapper (e.g. to start the JVM)
          // "delay": "1000m" // format as per :help sleep
        }
      }
    },
    "configurations": {
      "remote-launch": {
        "adapter": "python-remote",
  
        "remote-request": "launch",
        "remote-cmdLine": [
          "${RemoteRoot}/${fileBasename}", "*${args}"
        ],
  
        "configuration": {
          "request": "attach",
          "pathMappings": [
            {
              "localRoot": "${workspaceRoot}",
              "remoteRoot": "${RemoteRoot}"
            }
          ]
        }
      },
      "remote-attach": {
        "variables": {
          // Just an example of how to specify a variable manually rather than
          // vimspector asking for input from the user
          "ServiceName": "${fileBasenameNoExtension}"
        },
  
        "adapter": "python-remote",
        "remote-request": "attach",
  
        "configuration": {
          "request": "attach",
          "pathMappings": [
            {
              "localRoot": "${workspaceRoot}",
              "remoteRoot": "${RemoteRoot}"
            }
          ]
        }
      }
    }
  }
<
-------------------------------------------------------------------------------
                                              *vimspector-ref-c-family-example*
C-family (gdbserver) Example ~

This example uses Vimspector to remotely launch or attach to a binary using
'gdbserver' and then instructs vscode-cpptools to attach to that 'gdbserver'.

The approach is very similar to the above for python, just that we use
gdbserver and have to tell cpptools a few more options.
>
  {
    "adapters": {
      "cpptools-remote": {
        "command": [
          "${gadgetDir}/vscode-cpptools/debugAdapters/OpenDebugAD7"
        ],
        "name": "cppdbg",
        "configuration": {
          "type": "cppdbg"
        },
        "launch": {
          "remote": {
            "host": "${host}",
            "account": "${account}",
            "runCommand": [ 
              "gdbserver",
              "--once",
              "--no-startup-with-shell",
              "--disable-randomisation",
              "0.0.0.0:${port}",
              "%CMD%"
          }
        },
        "attach": {
          "remote": {
            "host": "${host}",
            "account": "${account}",
            "pidCommand": [
              "/path/to/secret/script/GetPIDForService", "${ServiceName}"
            ],
            "attachCommand": [ 
              "gdbserver",
              "--once",
              "--attach",
              "0.0.0.0:${port}",
              "%PID%"
            ],
            //
            // If your application is started by a wrapper script, then you might
            // need the followin. GDB can't pause an application because it only
            // sends the signal to the process group leader. Or something.
            // Basically, if you find that everything just hangs and the
            // application never attaches, try using the following to manually
            // force the trap signal.
            //
            "initCompleteCommand": [
              "kill",
              "-TRAP",
              "%PID%"
            ]
          }
        }
      }
    },
    "configurations": {
      "remote launch": {
        "adapter": "cpptools-remote",
        "remote-cmdLine": [ "/path/to/the/remote/executable", "args..." ],
        "remote-request": "launch",
        "configuration": {
          "request": "attach", // yes, attach!
  
          "program": "/path/to/the/local/executable",
          "MIMode": "gdb",
          "miDebuggerAddress": "${host}:${port}"
        }
      },
      "remote attach": {
        "adapter": "cpptools-remote",
        "remote-request": "attach",
        "configuration": {
          "request": "attach",
  
          "program": "/path/to/the/local/executable",
          "MIMode": "gdb",
          "miDebuggerAddress": "${host}:${port}"
      }
    }
  }
<
-------------------------------------------------------------------------------
                                                *vimspector-ref-docker-example*
Docker Example ~

This example uses Vimspector to remotely launch or attach to a docker container
port.
>
  {
    "adapters": {
      "python-remote": {
        "port": "${port}",
        "launch": {
          "remote": {
            "container": "${container}", // Docker container id or name to exec into to.
  
            // Command to launch the debugee and attach the debugger; 
            // %CMD% replaced with the remote-cmdLine configured in the launch
            // configuration. (mandatory)
            "runCommand": [
              "python", "-m", "debugpy",
              "--listen", "0.0.0.0:${port}",
              "--wait-for-client",
              "%CMD%"
            ]
  
            // Optional alternative to runCommand (if you need to run multiple
            // commands)
            // "runCommands":  [
            //   [ /* first command */ ],
            //   [ /* second command */ ]
            // ]
  
          }
  
          // optional delay to wait after running runCommand(s). This is often
          // needed because of the way docker handles TCP
          "delay": "1000m" // format as per :help sleep
        },
        "attach": {
          "remote": {
            "container": "${container}", // Docker container id or name to exec into.
            // Command to get the PID of the process to attach  (mandatory)
            // This command gets appended to "docker exec ${container}"
            "pidCommand": [
              //
              // Remember taht you can use ${var} to ask for input. I use this to
              // call a custom command to returm the PID for a named service, so
              // here's an examle:
              //
              "sh", "-c", "pgrep", "-f", "${filename}"
            ],
  
            // Command to attach the debugger; %PID% replaced with output of
            // pidCommand above (mandatory)
            "attachCommand": [
              "sh", "-c", "python", "-m", "debugpy", "--listen", "0.0.0.0:${port}",
              "--pid", "%PID%"
            ]
  
            // Optional alternative to attachCommand (if you need to run multiple
            // commands)
            // "attachCommands":  [
            //   [ /* first command */ ],
            //   [ /* second command */ ]
            // ],
  
            // Optional.... useful with buggy gdbservers to kill -TRAP %PID%
            // "initCompleteCommand": [
            //   /* optional command to run after initialized */
            // ]
  
          }
  
          // optional delay to wait after running runCommand(s). This is often
          // needed because of the way docker handles TCP, or if you're using some
          // wrapper (e.g. to start the JVM)
          "delay": "1000m" // format as per :help sleep
        }
      }
    },
    "configurations": {
      "remote-launch": {
        "adapter": "python-remote",
  
        "remote-request": "launch",
        "remote-cmdLine": [
          "${RemoteRoot}/${fileBasename}", "*${args}"
        ],
  
        "configuration": {
          "request": "attach",
          "pathMappings": [
            {
              "localRoot": "${workspaceRoot}",
              "remoteRoot": "${RemoteRoot}"
            }
          ]
        }
      },
      "remote-attach": {
        "variables": {
          // Just an example of how to specify a variable manually rather than
          // vimspector asking for input from the user
          "FileName": "${fileName}"
        },
  
        "adapter": "python-remote",
        "remote-request": "attach",
  
        "configuration": {
          "request": "attach",
          "pathMappings": [
            {
              "localRoot": "${workspaceRoot}",
              "remoteRoot": "${RemoteRoot}"
            }
          ]
        }
      }
    }
  }
<
===============================================================================
                            *vimspector-ref-appendix-configuration-file-format*
Appendix: Configuration file format ~

The configuration files are text files which must be UTF-8 encoded. They
contain a single JSON object, along with optional comments.

Comments are "c-style", i.e.:

- '// single line comment ...'
- '/* inline comment */'

There is much debate about whether JSON files should contain comments. I have
added them because they are useful in the context of configuration files.
Unforutnately this may mean your editor doesn't like them (they are strictly
invalid JSON) so it's up to you if you use them.

Technically, Vimspector uses JSON minify [3] to strip comments before parsing
the JSON.

===============================================================================
                                 *vimspector-ref-appendix-editor-configuration*
Appendix: Editor configuration ~

If you would like some assistance with writing the JSON files, and your editor
of choice has a way to use a language server, you can use the VSCode JSON
language server [4].

It is recommended to include the '$schema' declaration as in the above
examples, but if that isn't present, the following JSON language server
configuration [5] is recommened to load the schema from the Internet:
>
  {
    "json": {
      "schemas": [
        {
          "fileMatch": [ ".vimspector.json" ],
          "url": "https://puremourning.github.io/vimspector/schema/vimspector.schema.json"
        },
        {
          "fileMatch": [ ".gadgets.json", ".gadgets.d/*.json" ],
          "url": "https://puremourning.github.io/vimspector/schema/gadgets.schema.json"
        }
      ]
    }
  }
<
If your language server client of choice happens to be YouCompleteMe [6], then
the following '.ycm_extra_conf.py' is good enough to get you going, after
following the instructions in the lsp-examples [7] repo to get the server set
up:
>
  VIMSPECTOR_HOME = '/path/to/vimspector' # TODO: Change this
  
  def Settings( **kwargs ):
    if kwargs[ 'language' ] == 'json':
      return {
        'ls': {
          'json': {
            'schemas': [
              {
                'fileMatch': [ '.vimspector.json' ],
                'url': f'file://{VIMSPECTOR_HOME}/docs/schema/vimspector.schema.json'
              },
              {
                'fileMatch': [ '.gadgets.json', '.gadgets.d/*.json' ],
                'url': f'file://{VIMSPECTOR_HOME}/docs/schema/gadgets.schema.json'
              }
            ]
          }
        }
      }
  
    return None # Or your existing Settings definition....
<
This configuration can be adapted to any other LSP-based editor configuration
and is provided just as an example.

===============================================================================
                                                    *vimspector-ref-references*
References ~

[1] https://microsoft.github.io/debug-adapter-protocol/
[2] http://puremourning.github.io/vimspector/schema/vimspector.schema.json
[3] https://github.com/getify/JSON.minify
[4] https://github.com/vscode-langservers/vscode-json-languageserver
[5] https://github.com/vscode-langservers/vscode-json-languageserver#settings
[6] https://github.com/ycm-core/YouCompleteMe
[7] https://github.com/ycm-core/lsp-examples

vim: ft=help