add list of subcommands to README.md

README.md

@@ -13,7 +13,81 @@ For installation instructions, check out our docs on [Configuring Test Coverage]
 
 To sign up for Code Climate, head [here](https://codeclimate.com/quality/pricing/).
 
+---
 
+## Subcommands
+
+Some installations may require the use of the below subcommands (and their supported flags). 
+
+For example, here's an example of using the `--prefix` flag under the `after-build` subcommand:
+
+```cc-test-reporter after-build --prefix /home/rof/src/github.com/user_or_org_name/repo_name```
+
+---
+
+#### `format-coverage` 
+Formats test report from local test suite into generalized format, readable by Code Climate
+
+- `-t` or  `--input-type` *simplecov | lcov | coverage.py | gcov | clover* 
+  - Identifies the input type (format) of the COVERAGE_FILE
+
+- `-o PATH` or  `--output PATH` - Output to PATH. 
+  - If - is given, content will be written to stdout. Defaults to coverage/codeclimate.json.
+
+- `-p PATH` or `--prefix PATH` 
+  - The prefix to remove from absolute paths in coverage payloads, to make them relative to the project root. This is usually the directory in which the tests were run. Defaults to current working directory.
+
+- `COVERAGE_FILE` 
+  - Path to the coverage file to process. Defaults to searching known paths where coverage files could exist and selecting the first one found.
+
+- `-d` or `--debug`
+  - Outputs debug messages during operation.
+
+---
+
+#### `sum-coverage` 
+Combines test reports from multiple sources (i.e. multiple test suites or parallelized CI builds) into one test report which is readable by Code Climate
+
+- `-o PATH` or  `--output PATH` - Output to PATH. If - is given, content will be written to stdout. 
+  - Defaults to coverage/codeclimate.json.
+
+- `-p NUMBER` or `--parts NUMBER` 
+  - Expect NUMBER payloads to sum. If this many arguments are not present, command will error. This ensures you don't accidentally sum incomplete results.
+
+
+---
+
+
+#### `upload-coverage` 
+Uploads formatted, singular test report to Code Climate API
+
+- `-i PATH` or `--input PATH` 
+  - Read payload from PATH. If - is given, the payload will be read from stdin. Defaults to coverage/codeclimate.json.
+
+- `-r ID` or  `--id ID` 
+  - The reporter identifier to use when reporting coverage information. The appropriate value can be found in your Repository Settings page on codeclimate.com. Defaults to the value in the `CC_TEST_REPORTER_ID` environment variable. The uploader will error if a value is not found.
+
+- `-e URL` or `--endpoint URL` 
+  - The endpoint to upload coverage information to. Defaults to the value in the `CC_TEST_REPORTER_COVERAGE_ENDPOINT` environment variable, or a hard-coded default (currently `https://codeclimate.com/test_reports`).
+
+- `-d` or `--debug`
+  - Outputs debug messages during operation.
+
+---
+
+#### `after-build` 
+Combines `format-coverage` and `upload-coverage`
+
+- `--exit-code $EXIT_CODE` - `$EXIT_CODE` should be the exit code of your test suite process. 
+  - Some CI system expose this as an environment variable; for others, you may need to manually capture `$?` to provide it to `after-build` later. Providing this will prevent sending test coverage results for failed tests.
+
+- `-p PATH` or `--prefix PATH` 
+  - The prefix to remove from absolute paths in coverage payloads, to make them relative to the project root. This is usually the directory in which the tests were run. Defaults to current working directory.
+
+- `-d` or `--debug`
+  - Outputs debug messages during operation.
+
+---
 ## Copyright
 
 See the [LICENSE](https://github.com/codeclimate/test-reporter/blob/master/LICENSE).