# Introduction

This document outlines how to make hotfix binaries and containers for MinIO?. The main focus in this article is about how to backport patches to a specific branch and finally building binaries/containers.

## Pre-pre requisite

- A working knowledge of MinIO codebase and its various components.
- A working knowledge of AWS S3 API behaviors and corner cases.

## Pre-requisite for backporting any fixes

		return strings.HasSuffix(text, string(s)), nil
	}
	return string(s) == text, nil
}

// matcher - Finds `pat` in `text`, and returns the part remainder of
// `text`, after the match. If leadingPercent is false, `pat` must be
// the prefix of `text`, otherwise it must be a substring.
func matcher(text, pat string, leadingPercent bool) (res string, match bool) {
	if !leadingPercent {
		res = strings.TrimPrefix(text, pat)

                "color": "red",
                "value": 80
              }
            ]
          },
          "unit": "short"
        },
        "overrides": [
          {
            "matcher": {
              "id": "byName",
              "options": "Replication Errors"
            },
            "properties": [
              {
                "id": "color",
                "value": {

			},
			expected: ErrSignatureDoesNotMatch,
		},
		// (6) Should not error signature matches with extra query params.
		{
			queryParams: map[string]string{
				"response-content-disposition": "attachment; filename=\"4K%2d4M.txt\"",
			},
			expected: ErrNone,
		},
		// (7) Should not error signature matches with no special query params.
		{
			queryParams: map[string]string{},
			expected:    ErrNone,

                }
              },
              "type": "special"
            }
          ],
          "unit": "bytes"
        },
        "overrides": [
          {
            "matcher": {
              "id": "byName",
              "options": "Free"
            },
            "properties": [
              {
                "id": "color",
                "value": {

	}
	if len(c.Encoded) == 0 || c.Type.Trailing() {
		return c.Type.Is(ChecksumNone) || c.Type.Trailing()
	}
	raw := c.Raw
	return c.Type.RawByteLen() == len(raw)
}

// Matches returns whether given content matches c.
func (c Checksum) Matches(content []byte) error {
	if len(c.Encoded) == 0 {
		return nil
	}
	hasher := c.Type.Hasher()
	_, err := hasher.Write(content)
	if err != nil {
		return err
	}

By default, MinIO supports path-style requests that are of the format <http://mydomain.com/bucket/object>. `MINIO_DOMAIN` environment variable is used to enable virtual-host-style requests. If the request `Host` header matches with `(.+).mydomain.com` then the matched pattern `$1` is used as bucket and the path is used as object. Read more about path-style and virtual-host-style [here](http://docs.aws.amazon.com/AmazonS3/latest/dev/RESTAPI.html).

Example:

```sh

type ChecksumMismatch struct {
	Want string
	Got  string
}

func (e ChecksumMismatch) Error() string {
	return "Bad checksum: Want " + e.Want + " does not match calculated " + e.Got
}

// IsChecksumMismatch matches if 'err' is hash.ChecksumMismatch
func IsChecksumMismatch(err error) bool {
	var herr ChecksumMismatch
	return errors.As(err, &herr)

	local expected
	expected=$(mc cat "$1" | sha256sum)
	local got
	got=$(mc cat "$2" | sha256sum)

	if [ "${expected}" != "${got}" ]; then
		echo "mismatch - expected ${expected}, got ${got}"
		exit 1
	fi
	echo "matches - ${expected}, got ${got}"
}

add_alias() {
	for i in $(seq 1 4); do
		echo "... attempting to add alias $i"
		until (mc alias set minio http://127.0.0.1:9000 minioadmin minioadmin); do

		ppath := strings.TrimSuffix(path, "/") + "/"
		if strings.HasPrefix(mpath, ppath) {
			// At this point if the mount point has a common prefix two conditions can happen.
			// - mount.Path matches exact with `path` means we can proceed no error here.
			// - mount.Path doesn't match (means cross-device mount), should error out.
			if mount.Path != path {
				crossMounts = append(crossMounts, mount)
			}
		}