add grpc service definitions

This add the grpc protobuf service definitions for the new plugin
protocol, as well as the generated code.

plugin/proto/generate.go

@@ -0,0 +1,3 @@
+//go:generate protoc -I ./ plugin.proto --go_out=plugins=grpc:./
+
+package proto

plugin/proto/plugin.proto

@@ -0,0 +1,302 @@
+syntax = "proto3";
+
+package proto;
+
+// DynamicValue is an opaque encoding of terraform data, with the field name
+// indicating the encoding scheme used.
+message DynamicValue {
+    bytes msgpack = 1;
+    bytes json = 2;
+}
+
+message Diagnostic {
+    enum Severity {
+        INVALID = 0;
+        ERROR = 1;
+        WARNING = 2;
+    }
+    Severity severity = 1;
+    string summary = 2;
+    string detail = 3;
+    AttributePath attribute = 4;
+}
+
+message AttributePath {
+    message Step {
+        oneof selector {
+            // Set "attribute_name" to represent looking up an attribute
+            // in the current object value.
+            string attribute_name = 1;
+            // Set "element_key_*" to represent looking up an element in
+            // an indexable collection type.
+            string element_key_string = 2;
+            int64 element_key_int = 3;
+        }
+    }
+    repeated Step steps = 1;
+}
+
+message Stop {
+    message Request {
+    }
+    message Response {
+		string Error = 1;
+    }
+}
+
+// RawState holds the stored state for a resource to be upgraded by the
+// provider. It can be in one of two formats, the current json encoded format
+// in bytes, or the legacy flatmap format as a map of strings.
+message RawState {
+    bytes json = 1;
+    map<string, string> flatmap = 2;
+}
+
+// Schema is the configuration schema for a Resource, Provider, or Provisioner.
+message Schema {
+    message Block {
+        int64 version = 1;
+        repeated Attribute attributes = 2;
+        repeated NestedBlock block_types = 3;
+    }
+
+    message Attribute {
+        string name = 1;
+        bytes type = 2;
+        string description = 3;
+        bool required = 4;
+        bool optional = 5;
+        bool computed = 6;
+        bool sensitive = 7;
+    }
+
+    message NestedBlock {
+        enum NestingMode {
+            INVALID = 0;
+            SINGLE = 1;
+            LIST = 2;
+            SET = 3;
+            MAP = 4;
+        }
+
+        string type_name = 1;
+        Block block = 2;
+        NestingMode nesting = 3;
+        int64 min_items = 4;
+        int64 max_items = 5;
+    }
+
+    // The version of the schema.
+    // Schemas are versioned, so that providers can upgrade a saved resource
+    // state when the schema is changed. 
+    int64 version = 1;
+
+    // Block is the top level configuration block for this schema.
+    Block block = 2;
+}
+
+service Provider {
+    //////// Information about what a provider supports/expects
+    rpc GetSchema(GetProviderSchema.Request) returns (GetProviderSchema.Response);
+    rpc ValidateProviderConfig(ValidateProviderConfig.Request) returns (ValidateProviderConfig.Response);
+    rpc ValidateResourceTypeConfig(ValidateResourceTypeConfig.Request) returns (ValidateResourceTypeConfig.Response);
+    rpc ValidateDataSourceConfig(ValidateDataSourceConfig.Request) returns (ValidateDataSourceConfig.Response);
+    rpc UpgradeResourceState(UpgradeResourceState.Request) returns (UpgradeResourceState.Response);
+
+    //////// One-time initialization, called before other functions below
+    rpc Configure(Configure.Request) returns (Configure.Response);
+
+    //////// Managed Resource Lifecycle
+    rpc ReadResource(ReadResource.Request) returns (ReadResource.Response);
+    rpc PlanResourceChange(PlanResourceChange.Request) returns (PlanResourceChange.Response);
+    rpc ApplyResourceChange(ApplyResourceChange.Request) returns (ApplyResourceChange.Response);
+    rpc ImportResourceState(ImportResourceState.Request) returns (ImportResourceState.Response);
+
+    rpc ReadDataSource(ReadDataSource.Request) returns (ReadDataSource.Response);
+
+    //////// Graceful Shutdown
+    rpc Stop(Stop.Request) returns (Stop.Response);
+}
+
+message GetProviderSchema {
+    message Request {
+    }
+    message Response {
+        Schema provider = 1;
+        map<string, Schema> resource_schemas = 2;
+        map<string, Schema> data_source_schemas = 3;
+        repeated Diagnostic diagnostics = 4;
+    }
+}
+
+message ValidateProviderConfig {
+    message Request {
+        DynamicValue config = 1;
+    }
+    message Response {
+        repeated Diagnostic diagnostics = 1;
+    }
+}
+
+message UpgradeResourceState {
+    message Request {
+        string type_name = 1;
+
+        // version is the schema_version number recorded in the state file
+        int64 version = 2;
+
+        // raw_state is the raw states as stored for the resource.  Core does
+        // not have access to the schema of prior_version, so it's the
+        // provider's responsibility to interpret this value using the
+        // appropriate older schema. The raw_state will be the json encoded
+        // state, or a legacy flat-mapped format.
+        RawState raw_state = 3;
+    }
+    message Response {
+        // new_state is a msgpack-encoded data structure that, when interpreted with
+        // the _current_ schema for this resource type, is functionally equivalent to
+        // that which was given in prior_state_raw.
+        DynamicValue upgraded_state = 1;
+
+        // diagnostics describes any errors encountered during migration that could not
+        // be safely resolved, and warnings about any possibly-risky assumptions made
+        // in the upgrade process.
+        repeated Diagnostic diagnostics = 2;
+    }
+}
+
+message ValidateResourceTypeConfig {
+    message Request {
+        string type_name = 1;
+        DynamicValue config = 2;
+    }
+    message Response {
+        repeated Diagnostic diagnostics = 1;
+    }
+}
+
+message ValidateDataSourceConfig {
+    message Request {
+        string type_name = 1;
+        DynamicValue config = 2;
+    }
+    message Response {
+        repeated Diagnostic diagnostics = 1;
+    }
+}
+
+message Configure {
+    message Request {
+        string terraform_version = 1;
+        DynamicValue config = 2;
+    }
+    message Response {
+        repeated Diagnostic diagnostics = 1;
+    }
+}
+
+message ReadResource {
+    message Request {
+        string type_name = 1;
+        DynamicValue current_state = 2;
+    }
+    message Response {
+        DynamicValue new_state = 1;
+        repeated Diagnostic diagnostics = 2;
+    }
+}
+
+message PlanResourceChange {
+    message Request {
+        string type_name = 1;
+        DynamicValue prior_state = 2;
+        DynamicValue proposed_new_state = 3;
+        DynamicValue config = 4;
+        bytes prior_private = 5; 
+    }
+
+    message Response {
+        DynamicValue planned_state = 1;
+        repeated AttributePath requires_replace = 2;
+        bytes planned_private = 3; 
+        repeated Diagnostic diagnostics = 4;
+    }
+}
+
+message ApplyResourceChange {
+    message Request {
+        string type_name = 1;
+        DynamicValue prior_state = 2;
+        DynamicValue planned_state = 3;
+        DynamicValue config = 4;
+        bytes planned_private = 5; 
+    }
+    message Response {
+        DynamicValue new_state = 1;
+        bytes private = 2; 
+        repeated Diagnostic diagnostics = 3;
+    }
+}
+
+message ImportResourceState {
+    message Request {
+        string type_name = 1;
+        string id = 2;
+    }
+
+    message ImportedResource {
+        string type_name = 1;
+        DynamicValue state = 2;
+        bytes private = 3;
+    }
+
+    message Response {
+        repeated ImportedResource imported_resources = 1;
+        repeated Diagnostic diagnostics = 2;
+    }
+}
+
+message ReadDataSource {
+    message Request {
+        string type_name = 1;
+        DynamicValue config = 2;
+    }
+    message Response {
+        DynamicValue state = 1;
+        repeated Diagnostic diagnostics = 2;
+    }
+}
+
+service Provisioner {
+    rpc GetSchema(GetProvisionerSchema.Request) returns (GetProvisionerSchema.Response);
+    rpc ValidateProvisionerConfig(ValidateProvisionerConfig.Request) returns (ValidateProvisionerConfig.Response);
+    rpc ProvisionResource(ProvisionResource.Request) returns (stream ProvisionResource.Response);
+    rpc Stop(Stop.Request) returns (Stop.Response);
+}
+
+message GetProvisionerSchema {
+    message Request {
+    }
+    message Response {
+        Schema provisioner = 1;
+        repeated Diagnostic diagnostics = 2;
+    }
+}
+
+message ValidateProvisionerConfig {
+    message Request {
+        DynamicValue config = 1;
+    }
+    message Response {
+        repeated Diagnostic diagnostics = 1;
+    }
+}
+
+message ProvisionResource {
+    message Request {
+        DynamicValue config = 1;
+    }
+    message Response {
+        string output  = 1;
+    }   
+}