# Akamai\Open\EdgeGrid\Authentication::canonicalizeHeaders

#### Returns headers in normalized form

## Signature

`protected function canonicalizeHeaders()`

## Returns

string

## Test Coverage

### Information

- Coverage: 21/21 Lines (100%)
- Tests: 45
- Passed: 45 (100%)

### Tests

- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::simple GET with data set #0
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::GET with querystring with data set #1
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::POST inside limit with data set #2
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::POST too large with data set #3
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::POST length equals max_body with data set #4
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::POST empty body with data set #5
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::POST nil body with data set #6
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::Simple header signing with GET with data set #7
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::Header containing spaces with data set #8
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::Header with leading and interior spaces with data set #9
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::Headers out of order with data set #10
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::Extra header with data set #11
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::PUT test with data set #12
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::GET with query args as option with data set #13
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::testDefaultTimestamp
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::testDefaultNonce
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Client\AuthenticationTest::testSignHeadersArray
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #0
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #1
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #2
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #3
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #4
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #5
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #6
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #7
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #8
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #9
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #10
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #11
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #12
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeader with data set #13
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #0
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #1
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #2
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #3
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #4
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #5
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #6
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #7
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #8
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #9
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #10
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #11
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #12
- [ PASSED ] — Akamai\Open\EdgeGrid\Tests\Handler\AuthenticationTest::testMakeAuthHeaderPsr7 with data set #13