* Drop the iso_checksum_type & iso_checksum_url fields
In favor of simply using iso_checksum that will know what to do.
* fix after master merge
* Update builder_test.go
* Update builder_test.go
* Update builder_test.go
* Update builder_test.go
* Update builder_test.go
* remove checksum lowercasing tests
* Update builder_test.go
* Update builder_test.go
* better docs
* Update builder_test.go
* even better docs
* Update config.go
* Update builder_test.go
* Update step_create_vmx_test.go
* make generate
* better docs
* fix imports
* up tests
* Update _ISOConfig-required.html.md
* Update builder_test.go
* don't use sha1.Sum("none") as a caching path
* Update builder_test.go
* better docs
* Update iso_config_test.go
remove ISOChecksumType/ISOChecksumURL references
* Update step_download_test.go
* add iso_checksum_url and iso_checksum_type fixers + tests
* add concrete examples of checksum values
* add examples of checksumming from local file
* update go-getter dep
* up deps
* use new go-getter version
* up ESX5Driver.VerifyChecksum: use go-getter's checksumming
* ISOConfig.Prepare: get checksum there in case we need it as a string in ESX5Driver.VerifyChecksum
* Update iso_config.go
* get go-getter from v2 branch
* Update driver_esx5.go
add more comments
* Update driver_esx5.go
* show better error message when the checksum is invalid
* Update builder_test.go
put in a valid checksum to fix tests, checksum is md5("packer")
* Update builder_test.go
test invalid and valid checksum
* more test updating
* fix default md5 string to be a valid md5
* TestChecksumFileNameMixedCaseBug: use 'file:' prefix for file checksumming
* Update iso_config_test.go
* Update iso_config_test.go
* Update builder_test.go
* Update builder_test.go
* Update builder_test.go
* Update CHANGELOG.md
* Update CHANGELOG.md
* Update go.mod
* Update go.mod
* Update CHANGELOG.md
This change fixes an issue where using the `disk_additional_size` configuration option would cause builds to fail.
Build results before the change
```
==> Builds finished but no artifacts were created.
Build 'azure-arm' errored: Code="DeploymentFailed" Message="At least one resource deployment operation failed. Please list deployment operations for details. Please see https://aka.ms/DeployOperations for usage details." Details=[{"code":"BadRequest","message":"{\r\n \"error\": {\r\n \"code
\": \"InvalidParameter\",\r\n \"message\": \"The entity name 'dataDisk.name' is invalid according to its validation rule: ^[^_\\\\W][\\\\w-._]{0,79}(?\u003c![-.])$.\",\r\n \"target\": \"dataDisk.name\"\r\n }\r\n}"}]
```
Build results after change
```
Build 'azure-arm' finished.
==> Builds finished. The artifacts of successful builds are:
--> azure-arm: Azure.ResourceManagement.VMImage:
OSType: Linux
ManagedImageResourceGroupName: test-pkr
ManagedImageName: wilkenPacker9249
```
Closes#9249
