docs: reorganize and improve documentation

README.md

@@ -4,50 +4,159 @@
 [![codecov](https://codecov.io/gh/grafana/k6x/graph/badge.svg?token=nQA0QAF85R)](https://codecov.io/gh/grafana/k6x)
 ![GitHub Downloads](https://img.shields.io/github/downloads/grafana/k6x/total)
 
-<h1 name="title">k6x</h1>
-
 > [!Important]
 > The k6x is under refactor. This documentation is about the refactored code. Previous documentation is marked with the [before-grafana](https://github.com/grafana/k6x/tree/before-grafana) git tag. The last release before the refactor is [v0.4.0](https://github.com/grafana/k6x/releases/tag/v0.4.0).
 
-**Run k6 with extensions**
+<!-- #region cli -->
+# k6x
 
-k6x is a [k6](https://k6.io) launcher that automatically provides k6 with the [extensions](https://k6.io/docs/extensions/) used by the test. In order to do this, it analyzes the script arguments of the `run` and `archive` subcommands, detects the extensions to be used and their version constraints.
+Run k6 with extensions
 
-## Install
+## Synopsis
 
-Precompiled binaries can be downloaded and installed from the [Releases](https://github.com/grafana/k6x/releases) page.
+Run k6 with a seamless extension user experience.
 
-If you have a go development environment, the installation can also be done with the following command:
+`k6x` is a [k6] launcher that automatically provides [k6] with the [extensions] used by the test. In order to do this, it analyzes the script arguments of the `run` and `archive` subcommands, detects the extensions to be used and their version constraints.
+
+The launcher acts as a drop-in replacement for the `k6` command. For more convenient use, it is advisable to create an alias or shell script called `k6` for the launcher. The alias can be used in exactly the same way as the `k6` command, with the difference that it generates the real `k6` on the fly based on the extensions you want to use.
+
+The launcher will always run the k6 test script with the appropriate k6 binary, which contains the extensions used by the script. In order to do this, it analyzes the script arguments of the "run" and "archive" subcommands, detects the extensions to be used and their version constraints.
+
+Any k6 command can be used. Use the `help` command to list the available k6 commands.
+
+Any number of `"use k6"` pragmas can be used.
 
+### Pragma
+
+Version constraints can be specified using the JavaScript `"use ..."` pragma syntax for k6 and extensions. Put the following lines at the beginning of the test script:
+
+```js
+"use k6 >= v0.52";
+"use k6 with k6/x/faker > 0.2";
 ```
-go install github.com/grafana/k6x@latest
+
+> **Note**
+> The use of pragmas is completely optional for JavaScript type extensions, it is only necessary if you want to specify version constraints.
+
+The pragma syntax can also be used to specify an extension dependency that is not referenced in an import expression. A typical example of this is the Output type extension such as [xk6-top]:
+
+```js
+"use k6 with top >= 0.1";
 ```
 
-The launcher acts as a drop-in replacement for the k6 command. For more convenient use, it is advisable to create an alias or shell script called k6 for the launcher. The alias can be used in exactly the same way as the k6 command, with the difference that it generates the real k6 on the fly based on the extensions you want to use.
+Read the version constraints syntax in the [Version Constraints](#version-constraints) section
 
-## Usage
+### Environment
 
-<!-- #region cli -->
-## k6x
+The extensions to be used and optionally their version constraints can also be specified in the `K6_DEPENDENCIES` environment variable. The value of the `K6_DEPENDENCIES` environment variable is a comma-separated list of elements. Each element specifies an extension (or k6 itself) and optionally its version constraint.
 
-Lanch k6 with extensions
+```
+k6>=0.52;k6/x/faker>=0.3;k6/x/sql>=0.4
+```
 
-### Synopsis
+### Manifest
 
-Launch k6 with a seamless extension user experience.
+The manifest file is a JSON file, the `dependencies` property of which can specify extension dependencies and version constraints. The value of the `dependencies` property is a JSON object. The property names of this object are the extension names (or k6) and the values ​​are the version constraints.
 
-The launcher acts as a drop-in replacement for the `k6` command. For more convenient use, it is advisable to create an alias or shell script called `k6` for the launcher. The alias can be used in exactly the same way as the `k6` command, with the difference that it generates the real `k6` on the fly based on the extensions you want to use.
+```json
+{
+  "dependencies": {
+    "k6": ">=0.52",
+    "k6/x/faker": ">=0.3",
+    "k6/x/sql": ">=0.4"
+  }
+}
+```
 
-The launcher will always run the k6 test script with the appropriate k6 binary, which contains the extensions used by the script. In order to do this, it analyzes the script arguments of the "run" and "archive" subcommands, detects the extensions to be used and their version constraints.
+The manifest file is a file named `package.json`, which is located closest to the k6 test script or the current directory, depending on whether the given subcommand has a test script argument (e.g. run, archive) or not (e.g. version). The `package.json` file is searched for up to the root of the directory hierarchy.
+
+### Limitations
+
+Version constraints can be specified in several sources ([pragma](#pragma), [environment](#environment), [manifest](#manifest)) but cannot be overwritten. That is, for a given extension, the version constraints from different sources must either be equal, or only one source can contain a version constraint.
+
+### Version Constraints
+
+*This section is based on the [Masterminds/semver] documentation.*
+
+#### Basic Comparisons
+
+There are two elements to the comparisons. First, a comparison string is a list
+of space or comma separated AND comparisons. These are then separated by || (OR)
+comparisons. For example, `">= 1.2 < 3.0.0 || >= 4.2.3"` is looking for a
+comparison that's greater than or equal to 1.2 and less than 3.0.0 or is
+greater than or equal to 4.2.3.
+
+The basic comparisons are:
+
+* `=`: equal (aliased to no operator)
+* `!=`: not equal
+* `>`: greater than
+* `<`: less than
+* `>=`: greater than or equal to
+* `<=`: less than or equal to
+
+#### Hyphen Range Comparisons
+
+There are multiple methods to handle ranges and the first is hyphens ranges.
+These look like:
+
+* `1.2 - 1.4.5` which is equivalent to `>= 1.2 <= 1.4.5`
+* `2.3.4 - 4.5` which is equivalent to `>= 2.3.4 <= 4.5`
+
+#### Wildcards In Comparisons
+
+The `x`, `X`, and `*` characters can be used as a wildcard character. This works
+for all comparison operators. When used on the `=` operator it falls
+back to the patch level comparison (see tilde below). For example,
+
+* `1.2.x` is equivalent to `>= 1.2.0, < 1.3.0`
+* `>= 1.2.x` is equivalent to `>= 1.2.0`
+* `<= 2.x` is equivalent to `< 3`
+* `*` is equivalent to `>= 0.0.0`
+
+#### Tilde Range Comparisons (Patch)
+
+The tilde (`~`) comparison operator is for patch level ranges when a minor
+version is specified and major level changes when the minor number is missing.
+For example,
+
+* `~1.2.3` is equivalent to `>= 1.2.3, < 1.3.0`
+* `~1` is equivalent to `>= 1, < 2`
+* `~2.3` is equivalent to `>= 2.3, < 2.4`
+* `~1.2.x` is equivalent to `>= 1.2.0, < 1.3.0`
+* `~1.x` is equivalent to `>= 1, < 2`
+
+#### Caret Range Comparisons (Major)
+
+The caret (`^`) comparison operator is for major level changes once a stable
+(1.0.0) release has occurred. Prior to a 1.0.0 release the minor versions acts
+as the API stability level. This is useful when comparisons of API versions as a
+major change is API breaking. For example,
+
+* `^1.2.3` is equivalent to `>= 1.2.3, < 2.0.0`
+* `^1.2.x` is equivalent to `>= 1.2.0, < 2.0.0`
+* `^2.3` is equivalent to `>= 2.3, < 3`
+* `^2.x` is equivalent to `>= 2.0.0, < 3`
+* `^0.2.3` is equivalent to `>=0.2.3 <0.3.0`
+* `^0.2` is equivalent to `>=0.2.0 <0.3.0`
+* `^0.0.3` is equivalent to `>=0.0.3 <0.0.4`
+* `^0.0` is equivalent to `>=0.0.0 <0.1.0`
+* `^0` is equivalent to `>=0.0.0 <1.0.0`
 
-Any k6 command can be used. Use the `help` command to list the available k6 commands.
+
+**References**
+
+- [k6]: https://k6.io
+- [extensions]: https://grafana.com/docs/k6/latest/extensions/
+- [Masterminds/semver]: https://github.com/Masterminds/semver
+- [xk6-top]: https://github.com/szkiba/xk6-top
 
 
 ```
 k6x [flags] [command]
 ```
 
-### Flags
+## Flags
 
 ```
       --build-service-url string       URL of the k6 build service to be used
@@ -61,9 +170,72 @@ k6x [flags] [command]
 
 <!-- #endregion cli -->
 
+## Example
+
+```bash
+k6x run script.js
+```
+
+That's all!
+
+<details><summary>script.js</summary>
+
+```js file=script.js
+import { Faker } from "k6/x/faker";
+import sql from "k6/x/sql";
+
+const db = sql.open("sqlite3", "./test-users.db");
+
+export function setup() {
+  db.exec(`
+  CREATE TABLE IF NOT EXISTS users (
+    sub varchar PRIMARY KEY,
+    name varchar NOT NULL,
+    email varchar NOT NULL
+  );`);
+
+  const faker = new Faker(11);
+
+  db.exec(`
+    INSERT OR REPLACE INTO users (sub, name, email) VALUES (
+      '${faker.internet.username()}',
+      '${faker.person.firstName()} ${faker.person.lastName()}',
+      '${faker.person.email()}'
+    );`);
+}
+
+export function teardown() {
+  db.close();
+}
+
+export default function () {
+  const results = sql.query(db, "SELECT * FROM users");
+
+  for (const row of results) {
+    const { sub, name, email } = row;
+
+    console.log({ sub, name, email });
+  }
+}
+```
+
+</details>
+
+## Install
+
+Precompiled binaries can be downloaded and installed from the [Releases](https://github.com/grafana/k6x/releases) page.
+
+If you have a go development environment, the installation can also be done with the following command:
+
+```
+go install github.com/grafana/k6x@latest
+```
+
+The launcher acts as a drop-in replacement for the k6 command. For more convenient use, it is advisable to create an alias or shell script called k6 for the launcher. The alias can be used in exactly the same way as the k6 command, with the difference that it generates the real k6 on the fly based on the extensions you want to use.
+
 ## Contributing
 
-If you want to contribute, please read the [CONTRIBUTING.md](.github/CONTRIBUTING.md) file.
+If you want to contribute, please read the [CONTRIBUTING.md](CONTRIBUTING.md) file.
 
 ### Tasks
 
@@ -75,7 +247,7 @@ This section contains a description of the tasks performed during development. C
 
 Update documentation in README.md.
 
-```
+```sh
 go run ./tools/gendoc README.md
 ```
 
@@ -85,7 +257,7 @@ Run the static analyzer.
 
 We make use of the [golangci-lint](https://github.com/golangci/golangci-lint) tool to lint the code in CI. The actual version you can find in our [`.golangci.yml`](https://github.com/grafana/k6x/blob/master/.golangci.yml#L1).
 
-```
+```sh
 golangci-lint run
 ```
 
@@ -95,16 +267,15 @@ Run the tests.
 
 To exercise the entire test suite, please run the following command
 
-
-```
+```sh
 go test -count 1 -race -coverprofile=build/coverage.txt ./...
 ```
 
 #### coverage
 
 View the test coverage report.
 
-```
+```sh
 go tool cover -html=build/coverage.txt
 ```
 
@@ -114,7 +285,7 @@ Build the executable binary.
 
 This is the easiest way to create an executable binary (although the release process uses the goreleaser tool to create release versions).
 
-```
+```sh
 go build -ldflags="-w -s" -o k6x .
 ```
 
@@ -124,7 +295,7 @@ Creating an executable binary with a snapshot version.
 
 The goreleaser command-line tool is used during the release process. During development, it is advisable to create binaries with the same tool from time to time.
 
-```
+```sh
 goreleaser build --snapshot --clean --single-target -o k6x
 ```
 
@@ -134,15 +305,25 @@ Building a Docker image. Before building the image, it is advisable to perform a
 
 Requires: snapshot
 
-```
+```sh
 docker build -t grafana/k6x -f Dockerfile.goreleaser .
 ```
 
+#### examples
+
+Run all scripts in the `examples` directory with a fresh build.
+
+Requires: clean, snapshot
+
+```sh
+find  examples -type f | xargs -n 1 ./k6x run
+```
+
 #### clean
 
 Delete the build directory.
 
-```
+```sh
 rm -rf build
 ```
 

internal/cmd/cmd.go

@@ -16,8 +16,8 @@ func New(levelVar *slog.LevelVar) *cobra.Command {
 	state := newState(levelVar)
 
 	root := &cobra.Command{
-		Use:               "exec [flags] [command]",
-		Short:             "Lanch k6 with extensions",
+		Use:               "k6x [flags] [command]",
+		Short:             "Run k6 with extensions",
 		Long:              help,
 		SilenceUsage:      true,
 		SilenceErrors:     true,