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diff --git a/docs/getting_started/debugging_your_code.md b/docs/getting_started/debugging_your_code.md deleted file mode 100644 index 04bd711cd..000000000 --- a/docs/getting_started/debugging_your_code.md +++ /dev/null @@ -1,145 +0,0 @@ -## Debugging your code - -Deno supports the [V8 Inspector Protocol](https://v8.dev/docs/inspector). - -It's possible to debug Deno programs using Chrome Devtools or other clients that -support the protocol (eg. VSCode). - -To activate debugging capabilities run Deno with the `--inspect` or -`--inspect-brk` flags. - -The `--inspect` flag allows attaching the debugger at any point in time, while -`--inspect-brk` will wait for the debugger to attach and will pause execution on -the first line of code. - -### Chrome Devtools - -Let's try debugging a program using Chrome Devtools. For this, we'll use -[file_server.ts](https://deno.land/std@$STD_VERSION/http/file_server.ts) from -`std`, a static file server. - -Use the `--inspect-brk` flag to break execution on the first line: - -```shell -$ deno run --inspect-brk --allow-read --allow-net https://deno.land/std@$STD_VERSION/http/file_server.ts -Debugger listening on ws://127.0.0.1:9229/ws/1e82c406-85a9-44ab-86b6-7341583480b1 -Download https://deno.land/std@$STD_VERSION/http/file_server.ts -Compile https://deno.land/std@$STD_VERSION/http/file_server.ts -... -``` - -Open `chrome://inspect` and click `Inspect` next to target: - - - -It might take a few seconds after opening the Devtools to load all modules. - - - -You might notice that Devtools paused execution on the first line of -`_constants.ts` instead of `file_server.ts`. This is expected behavior and is -caused by the way ES modules are evaluated by V8 (`_constants.ts` is left-most, -bottom-most dependency of `file_server.ts` so it is evaluated first). - -At this point all source code is available in the Devtools, so let's open up -`file_server.ts` and add a breakpoint there; go to "Sources" pane and expand the -tree: - - - -_Looking closely you'll find duplicate entries for each file; one written -regularly and one in italics. The former is compiled source file (so in the case -of `.ts` files it will be emitted JavaScript source), while the latter is a -source map for the file._ - -Next, add a breakpoint in the `listenAndServe` method: - - - -As soon as we've added the breakpoint Devtools automatically opened up the -source map file, which allows us step through the actual source code that -includes types. - -Now that we have our breakpoints set, we can resume the execution of our script -so that we might inspect an incoming request. Hit the Resume script execution -button to do so. You might even need to hit it twice! - -Once our script is running again, let's send a request and inspect it in -Devtools: - -``` -$ curl http://0.0.0.0:4507/ -``` - - - -At this point we can introspect the contents of the request and go step-by-step -to debug the code. - -### VSCode - -Deno can be debugged using VSCode. - -Official support via the plugin is being worked on - -https://github.com/denoland/vscode_deno/issues/12 - -We can still attach the debugger by manually providing a -[`launch.json`](https://code.visualstudio.com/docs/editor/debugging#_launch-configurations) -config: - -```json -{ - "version": "0.2.0", - "configurations": [ - { - "name": "Deno", - "type": "pwa-node", - "request": "launch", - "cwd": "${workspaceFolder}", - "runtimeExecutable": "deno", - "runtimeArgs": ["run", "--inspect-brk", "-A", "${file}"], - "attachSimplePort": 9229 - } - ] -} -``` - -**NOTE**: This uses the file you have open as the entry point; replace `${file}` -with a script name if you want a fixed entry point. - -Let's try out debugging a local source file. Create `server.ts`: - -```ts -import { serve } from "https://deno.land/std@$STD_VERSION/http/server.ts"; -const server = serve({ port: 8000 }); -console.log("http://localhost:8000/"); - -for await (const req of server) { - req.respond({ body: "Hello World\n" }); -} -``` - -Then we can set a breakpoint, and run the created configuration: - - - -### JetBrains IDEs - -You can debug Deno using your JetBrains IDE by right-clicking the file you want -to debug and selecting the `Debug 'Deno: <file name>'` option. This will create -a run/debug configuration with no permission flags set. To configure these flags -edit the run/debug configuration and modify the `Arguments` field with the -required flags. - -### Other - -Any client that implements the Devtools protocol should be able to connect to a -Deno process. - -### Limitations - -Devtools support is still immature. There is some functionality that is known to -be missing or buggy: - -- autocomplete in Devtools' console causes the Deno process to exit. -- profiling and memory dumps might not work correctly. |