This change performs template expansion both for root stack documents in
addition to the transitive closure of dependencies. There are many ongoing
design and implementation questions about how this should actually work;
please see marapongo/mu#7 for a discussion of them.
This change implements dependency versions, including semantic analysis, per the
checkin 83030685c3.
There's quite a bit in here but at a top-level this parses and validates dependency
references of the form
[[proto://]base.url]namespace/.../name[@version]
and verifies that the components are correct, as well as binding them to symbols.
These references can appear in two places at the moment:
* Service types.
* Cluster dependencies.
As part of this change, a number of supporting changes have been made:
* Parse Workspaces using a full-blown parser, parser analysis, and semantic analysis.
This allows us to share logic around the validation of common AST types. This also
moves some of the logic around loading workspace.yaml files back to the parser, where
it can be unified with the way we load Mu.yaml files.
* New ast.Version and ast.VersionSpec types. The former represents a precise version
-- either a specific semantic version or a short or long Git SHA hash -- and the
latter represents a range -- either a Version, "latest", or a semantic range.
* New ast.Ref and ast.RefParts types. The former is an unparsed string that is
thought to contain a Ref, while the latter is a validated Ref that has been parsed
into its components (Proto, Base, Name, and Version).
* Added some type assertions to ensure certain structs implement certain interfaces,
to speed up finding errors. (And remove the coercions that zero-fill vtbl slots.)
* Be consistent about prefixing error types with Error or Warning.
* Organize the core compiler driver's logic into three methods, FE, sema, and BE.
* A bunch of tests for some of the above ... more to come in an upcoming change.
This change adds support for Workspaces, a convenient way of sharing settings
among many Stacks, like default cluster targets, configuration settings, and the
like, which are not meant to be distributed as part of the Stack itself.
The following things are included in this checkin:
* At workspace initialization time, detect and parse the .mu/workspace.yaml
file. This is pretty rudimentary right now and contains just the default
cluster targets. The results are stored in a new ast.Workspace type.
* Rename "target" to "cluster". This impacts many things, including ast.Target
being changed to ast.Cluster, and all related fields, the command line --target
being changed to --cluster, various internal helper functions, and so on. This
helps to reinforce the desired mental model.
* Eliminate the ast.Metadata type. Instead, the metadata moves directly onto
the Stack. This reflects the decision to make Stacks "the thing" that is
distributed, versioned, and is the granularity of dependency.
* During cluster targeting, add the workspace settings into the probing logic.
We still search in the same order: CLI > Stack > Workspace.
This change lays some groundwork that registers symbols when doing semantic
analysis of the resulting AST. For now, that just entails detecting duplicate
services by way of symbol registration.
Note that we've also split binding into two phases to account for the fact
that intra-stack dependencies are wholly legal.
This change adds a few more compiler tests and rearranges some bits and pieces
that came up while doing so. For example, we now issue warnings for incorrect
casing and/or extensions of the Mufile (and test these conditions). As part of
doing that, it became clear the layering between the mu/compiler and mu/workspace
packages wasn't quite right, so some logic got moved around; additionally, the
separation of concerns between mu/workspace and mu/schema wasn't quite right, so
this has been fixed also (workspace just understands Mufile related things while
schema understands how to unmarshal the specific supported extensions).
This adds a bunch of general scaffolding and the beginning of a `build` command.
The general engineering scaffolding includes:
* Glide for dependency management.
* A Makefile that runs govet and golint during builds.
* Google's Glog library for logging.
* Cobra for command line functionality.
The Mu-specific scaffolding includes some packages:
* mu/pkg/diag: A package for compiler-like diagnostics. It's fairly barebones
at the moment, however we can embellish this over time.
* mu/pkg/errors: A package containing Mu's predefined set of errors.
* mu/pkg/workspace: A package containing workspace-related convenience helpers.
in addition to a main entrypoint that simply wires up and invokes the CLI. From
there, the mu/cmd package takes over, with the Cobra-defined CLI commands.
Finally, the mu/pkg/compiler package actually implements the compiler behavior.
Or, it will. For now, it simply parses a JSON or YAML Mufile into the core
mu/pkg/api types, and prints out the result.
