1 Commits (f-cliconfig-hcl2api)

Author	SHA1	Message	Date
Martin Atkins	7e87b640bc	command/cliconfig/syntax: Just enough HCL 2 API for CLI Config decoding ... For compatibility reasons we can't use the HCL 2 parser to parse the CLI config: our historical format uses an incompatible syntax for environment variable substitutions in certain values. However, the HCL 1 decoding API makes it impossible to deal with certain configuration structures involving sequences of blocks of different types where ordering must be preserved, which we need for a forthcoming feature to specify provider installation locations. To deal with this empasse, here we have an implementation of the relevant parts of the HCL 2 API in terms of the HCL 1 AST, mimicking the important HCL 1 decoder behaviors, so that we can use HCL 2 patterns for decoding while still using HCL 1 syntax and the custom environment variable substitution syntax for backward-compatibility. The main goal here is that it be possible to write a CLI configuration that both the new and old implementations can consume, without creating any significant ambiguities for either implementation. This might have some slight incompatibilities with existing CLI configs as written due to how liberal the HCL 1 decoder tends to be, but it should be broadly compatible with CLI configuration syntax as documented and with reasonable variants.	6 years ago