Flexible config via CLI options

README.md

@@ -161,7 +161,35 @@ GTS_DOCKER_TAGS=1.0.1 1.0
 
 As you can see, the resolved version is not the highest in the repository, but as it is the highest within its minor version the Docker tags include `1.0` as well.
 
+## Configuration
+
+TODO
+
+### Configuration overrides
+
+You can override any configuration value from the command line using the `-c/--config-value` option. This is useful for one-off changes without modifying the config file:
+
+```shell
+# Override JSON output indentation
+git-that-semver -o json -c output.json.indent=2
+
+# Configure environment variable prefix
+git-that-semver -c output.env.prefix=CUSTOM_
+
+# Enable/disable strategies
+git-that-semver -c strategies.npm.enabled=true
+
+# Configure default branches (using JSON array syntax)
+git-that-semver -c 'defaults.snapshot.defaultBranches=["main","develop"]'
+
+# Disable change request identifier for snapshots
+git-that-semver -c defaults.snapshot.useChangeRequestIdentifier=false
+
+# Configure snapshot version template
+git-that-semver -c 'defaults.snapshot.versionTpl={{ prefix }}-{{ commitIdentifier }}'
+```
+
 ## TODOs
 
 - dynamic loading of SCM adapters?
-- logging to STDERR colorizes to the output to red by default - this is overridden and works as long as the output is not redirected, but results in red output otherwise - any way to fix this?
+- logging to STDERR colorizes to the output to red by default - this is overridden and works as long as the output is not redir

index.ts

@@ -15,12 +15,18 @@ const program = new Command("git-that-semver")
   .version("0.0.1")
   .addOption(
     new Option(
-      "-c, --config-file <configFile>",
+      "-f, --config-file <config-file>",
       "Config file (git-that-semver.yaml)",
     )
       .env("GTS_CONFIG_FILE")
       .default("git-that-semver.yaml"),
   )
+  .addOption(
+    new Option(
+      "-c, --config-value <config-values...>",
+      "Override config values (e.g. output.json.indent=2)",
+    ).default([]),
+  )
   .addOption(
     new Option("--log-level <level>", "Log level")
       .env("GTS_LOG_LEVEL")
@@ -29,13 +35,13 @@ const program = new Command("git-that-semver")
   )
   .addOption(
     new Option(
-      "-e, --enable-strategies <strategies...>",
+      "-e, --enable-strategy <strategies...>",
       "Enable strategies by name",
     ).default([]),
   )
   .addOption(
     new Option(
-      "-d, --disable-strategies <strategies...>",
+      "-d, --disable-strategy <strategies...>",
       "Disable strategies by name",
     ).default([]),
   )
@@ -58,9 +64,10 @@ logger.setLevel(LogLevel[program.opts().logLevel]);
 try {
   const config = await resolveConfig(
     path.resolve(program.opts().configFile),
-    [...program.opts().enableStrategies],
-    [...program.opts().disableStrategies],
+    [...program.opts().enableStrategy],
+    [...program.opts().disableStrategy],
     program.opts().outputFormat,
+    [...program.opts().configValue],
   );
 
   if (program.opts().dumpConfig) {

package.json

@@ -6,6 +6,7 @@
     "@commander-js/extra-typings": "^13.0.0",
     "@trivago/prettier-plugin-sort-imports": "^5.2.1",
     "@types/bun": "^1.1.18",
+    "@types/lodash-es": "^4.17.12",
     "@types/semver": "^7.5.8",
     "@types/slug": "^5.0.9",
     "husky": "^9.1.7",
@@ -19,6 +20,7 @@
     "chalk": "^5.4.1",
     "commander": "^13.1.0",
     "liquidjs": "^10.20.2",
+    "lodash-es": "^4.17.21",
     "merge-anything": "^6.0.2",
     "semver": "^7.6.3",
     "slug": "^10.0.0",

src/config/index.ts

@@ -3,6 +3,7 @@ import YAML from "yaml";
 
 import { logger } from "../logging";
 import defaultConfigContents from "./git-that-semver.default.yaml" with { type: "text" };
+import { applyConfigOverrides } from "./overrides";
 import { Config } from "./types";
 
 const configLogger = logger.childLogger("config");
@@ -12,6 +13,7 @@ export const resolveConfig = async (
   enabledStrategies: string[],
   disabledStrategies: string[],
   outputFormat: string | undefined,
+  configOverrides: string[] = [],
 ): Promise<Config> => {
   const defaultConfig = YAML.parse(defaultConfigContents);
   configLogger.trace("Default config", defaultConfig);
@@ -49,6 +51,11 @@ export const resolveConfig = async (
     mergedConfig = merge(mergedConfig, { output: { type: outputFormat } });
   }
 
+  if (configOverrides.length > 0) {
+    configLogger.trace("Config overrides", configOverrides);
+    mergedConfig = applyConfigOverrides(mergedConfig, configOverrides);
+  }
+
   configLogger.trace("Merged config before strategy merge", mergedConfig);
 
   const defaultsWithoutBranchPrefixes = merge({}, mergedConfig.defaults ?? {});

src/config/overrides.ts

@@ -0,0 +1,61 @@
+import { set } from "lodash-es";
+
+import { logger } from "../logging";
+
+const configLogger = logger.childLogger("config");
+
+function parseConfigOverride(override: string): { path: string; value: any } {
+  if (!/^[^=]+=[^=]*$/.test(override)) {
+    throw new Error(
+      `Invalid config value format: ${override}. Expected format: path.to.config=value`,
+    );
+  }
+
+  const [path, value] = override.split("=", 2);
+  return { path, value: parseValue(value) };
+}
+
+function parseValue(value: string | undefined): any {
+  if (value === undefined) {
+    return undefined;
+  }
+
+  // Handle boolean values
+  if (value.toLowerCase() === "true") return true;
+  if (value.toLowerCase() === "false") return false;
+
+  // Handle array values (JSON array syntax)
+  if (value.startsWith("[") && value.endsWith("]")) {
+    try {
+      return JSON.parse(value);
+    } catch (e) {
+      throw new Error(
+        `Invalid array format: ${value}. Expected JSON array format like [value1,value2]`,
+      );
+    }
+  }
+
+  // Handle numeric values
+  const numValue = Number(value);
+  if (!isNaN(numValue) && value.trim() !== "") {
+    return numValue;
+  }
+
+  // Return as string if no other type matches
+  return value;
+}
+
+export function applyConfigOverrides(
+  config: Record<string, any>,
+  overrides: string[],
+): Record<string, any> {
+  const result = { ...config };
+
+  for (const override of overrides) {
+    const { path, value } = parseConfigOverride(override);
+    configLogger.trace("Applying config override", { path, value });
+    set(result, path, value);
+  }
+
+  return result;
+}

src/config/types.ts

@@ -42,6 +42,11 @@ export const OutputConfig = z.object({
   env: z.object({
     prefix: z.string().default(""),
   }),
+  json: z
+    .object({
+      indent: z.number().optional(),
+    })
+    .optional(),
 });
 
 export const Config = z.object({

src/output/json.test.ts

@@ -20,20 +20,57 @@ describe("JsonOutputPrinter", () => {
     consoleSpy.mockRestore();
   });
 
-  const testPrintResult = (description: string, versionResult: any) => {
-    it(`should print ${description} as formatted JSON`, () => {
-      printer.printResult({} as Config, versionResult);
+  const testPrintResult = (
+    description: string,
+    versionResult: any,
+    indent: number = 2,
+  ) => {
+    it(`should print ${description} as formatted JSON with indent ${indent}`, () => {
+      const config = {
+        output: {
+          json: {
+            indent,
+          },
+        },
+      } as Config;
+
+      printer.printResult(config, versionResult);
 
       expect(consoleSpy).toHaveBeenCalledTimes(1);
       expect(consoleSpy).toHaveBeenCalledWith(
-        JSON.stringify(versionResult, null, 2),
+        JSON.stringify(versionResult, null, indent),
       );
 
       const printedJson = JSON.parse(consoleSpy.mock.calls[0][0]);
       expect(printedJson).toEqual(versionResult);
     });
   };
 
-  testPrintResult("release version result", releaseVersionResult);
-  testPrintResult("snapshot version result", snapshotVersionResult);
+  describe("with default indent (2)", () => {
+    testPrintResult("release version result", releaseVersionResult);
+    testPrintResult("snapshot version result", snapshotVersionResult);
+  });
+
+  describe("with custom indent", () => {
+    testPrintResult(
+      "release version result with no indent",
+      releaseVersionResult,
+      0,
+    );
+    testPrintResult(
+      "snapshot version result with no indent",
+      snapshotVersionResult,
+      0,
+    );
+    testPrintResult(
+      "release version result with indent 4",
+      releaseVersionResult,
+      4,
+    );
+    testPrintResult(
+      "snapshot version result with indent 4",
+      snapshotVersionResult,
+      4,
+    );
+  });
 });

src/output/json.ts

@@ -3,7 +3,9 @@ import type { Config } from "../config/types";
 import type { VersionResult } from "../version/versionResolver";
 
 export class JsonOutputPrinter implements OutputPrinter {
-  printResult(_config: Config, versionResult: VersionResult) {
-    console.log(JSON.stringify(versionResult, null, 2));
+  printResult(config: Config, versionResult: VersionResult) {
+    console.log(
+      JSON.stringify(versionResult, null, config.output.json?.indent),
+    );
   }
 }