// Copyright (c) The OpenTofu Authors
// SPDX-License-Identifier: MPL-2.0
// Copyright (c) 2023 HashiCorp, Inc.
// SPDX-License-Identifier: MPL-2.0

// Terraform Plugin RPC protocol version 6.4
//
// This file defines version 6.4 of the RPC protocol. To implement a plugin
// against this protocol, copy this definition into your own codebase and
// use protoc to generate stubs for your target language.
//
// This file will not be updated. Any minor versions of protocol 6 to follow
// should copy this file and modify the copy while maintaining backwards
// compatibility. Breaking changes, if any are required, will come
// in a subsequent major version with its own separate proto definition.
//
// Note that only the proto files included in a release tag of Terraform are
// official protocol releases. Proto files taken from other commits may include
// incomplete changes or features that did not make it into a final release.
// In all reasonable cases, plugin developers should take the proto file from
// the tag of the most recent release of Terraform, and not from the main
// branch or any other development branch.
//
syntax = "proto3";
option go_package = "github.com/opentofu/opentofu/internal/tfplugin6";

package tfplugin6;

// 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 StopProvider {
    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;
}

enum StringKind {
    PLAIN = 0;
    MARKDOWN = 1;
}

// Schema is the configuration schema for a Resource or Provider.
message Schema {
    message Block {
        int64 version = 1;
        repeated Attribute attributes = 2;
        repeated NestedBlock block_types = 3;
        string description = 4;
        StringKind description_kind = 5;
        bool deprecated = 6;
    }

    message Attribute {
        string name = 1;
        bytes type = 2;
        Object nested_type = 10;
        string description = 3;
        bool required = 4;
        bool optional = 5;
        bool computed = 6;
        bool sensitive = 7;
        StringKind description_kind = 8;
        bool deprecated = 9;
    }

    message NestedBlock {
        enum NestingMode {
            INVALID = 0;
            SINGLE = 1;
            LIST = 2;
            SET = 3;
            MAP = 4;
            GROUP = 5;
        }

        string type_name = 1;
        Block block = 2;
        NestingMode nesting = 3;
        int64 min_items = 4;
        int64 max_items = 5;
    }

    message Object {
        enum NestingMode {
            INVALID = 0;
            SINGLE = 1;
            LIST = 2;
            SET = 3;
            MAP = 4;
        }

        repeated Attribute attributes = 1;
        NestingMode nesting = 3;

        // MinItems and MaxItems were never used in the protocol, and have no
        // effect on validation.
        int64 min_items = 4 [deprecated = true];
        int64 max_items = 5 [deprecated = true];
    }

    // 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 GetProviderSchema(GetProviderSchema.Request) returns (GetProviderSchema.Response);
    rpc ValidateProviderConfig(ValidateProviderConfig.Request) returns (ValidateProviderConfig.Response);
    rpc ValidateResourceConfig(ValidateResourceConfig.Request) returns (ValidateResourceConfig.Response);
    rpc ValidateDataResourceConfig(ValidateDataResourceConfig.Request) returns (ValidateDataResourceConfig.Response);
    rpc UpgradeResourceState(UpgradeResourceState.Request) returns (UpgradeResourceState.Response);

    //////// One-time initialization, called before other functions below
    rpc ConfigureProvider(ConfigureProvider.Request) returns (ConfigureProvider.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 StopProvider(StopProvider.Request) returns (StopProvider.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;
        Schema provider_meta = 5;
        ServerCapabilities server_capabilities = 6;
    }


    // ServerCapabilities allows providers to communicate extra information
    // regarding supported protocol features. This is used to indicate
    // availability of certain forward-compatible changes which may be optional
    // in a major protocol version, but cannot be tested for directly.
    message ServerCapabilities {
        // The plan_destroy capability signals that a provider expects a call
        // to PlanResourceChange when a resource is going to be destroyed.
        bool plan_destroy = 1;

        // The get_provider_schema_optional capability indicates that this
        // provider does not require calling GetProviderSchema to operate
        // normally, and the caller can used a cached copy of the provider's
        // schema.
        bool get_provider_schema_optional = 2;
    }
}

message ValidateProviderConfig {
    message Request {
        DynamicValue config = 1;
    }
    message Response {
        repeated Diagnostic diagnostics = 2;
    }
}

message UpgradeResourceState {
    // Request is the message that is sent to the provider during the
    // UpgradeResourceState RPC.
    //
    // This message intentionally does not include configuration data as any
    // configuration-based or configuration-conditional changes should occur
    // during the PlanResourceChange RPC. Additionally, the configuration is
    // not guaranteed to exist (in the case of resource destruction), be wholly
    // known, nor match the given prior state, which could lead to unexpected
    // provider behaviors for practitioners.
    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 ValidateResourceConfig {
    message Request {
        string type_name = 1;
        DynamicValue config = 2;
    }
    message Response {
        repeated Diagnostic diagnostics = 1;
    }
}

message ValidateDataResourceConfig {
    message Request {
        string type_name = 1;
        DynamicValue config = 2;
    }
    message Response {
        repeated Diagnostic diagnostics = 1;
    }
}

message ConfigureProvider {
    message Request {
        string terraform_version = 1;
        DynamicValue config = 2;
    }
    message Response {
        repeated Diagnostic diagnostics = 1;
    }
}

message ReadResource {
    // Request is the message that is sent to the provider during the
    // ReadResource RPC.
    //
    // This message intentionally does not include configuration data as any
    // configuration-based or configuration-conditional changes should occur
    // during the PlanResourceChange RPC. Additionally, the configuration is
    // not guaranteed to be wholly known nor match the given prior state, which
    // could lead to unexpected provider behaviors for practitioners.
    message Request {
        string type_name = 1;
        DynamicValue current_state = 2;
        bytes private = 3;
        DynamicValue provider_meta = 4;
    }
    message Response {
        DynamicValue new_state = 1;
        repeated Diagnostic diagnostics = 2;
        bytes private = 3;
    }
}

message PlanResourceChange {
    message Request {
        string type_name = 1;
        DynamicValue prior_state = 2;
        DynamicValue proposed_new_state = 3;
        DynamicValue config = 4;
        bytes prior_private = 5;
        DynamicValue provider_meta = 6;
    }

    message Response {
        DynamicValue planned_state = 1;
        repeated AttributePath requires_replace = 2;
        bytes planned_private = 3;
        repeated Diagnostic diagnostics = 4;

        // This may be set only by the helper/schema "SDK" in the main Terraform
        // repository, to request that Terraform Core >=0.12 permit additional
        // inconsistencies that can result from the legacy SDK type system
        // and its imprecise mapping to the >=0.12 type system.
        // The change in behavior implied by this flag makes sense only for the
        // specific details of the legacy SDK type system, and are not a general
        // mechanism to avoid proper type handling in providers.
        //
        //     ====              DO NOT USE THIS              ====
        //     ==== THIS MUST BE LEFT UNSET IN ALL OTHER SDKS ====
        //     ====              DO NOT USE THIS              ====
        bool legacy_type_system = 5;
    }
}

message ApplyResourceChange {
    message Request {
        string type_name = 1;
        DynamicValue prior_state = 2;
        DynamicValue planned_state = 3;
        DynamicValue config = 4;
        bytes planned_private = 5;
        DynamicValue provider_meta = 6;
    }
    message Response {
        DynamicValue new_state = 1;
        bytes private = 2;
        repeated Diagnostic diagnostics = 3;

        // This may be set only by the helper/schema "SDK" in the main Terraform
        // repository, to request that Terraform Core >=0.12 permit additional
        // inconsistencies that can result from the legacy SDK type system
        // and its imprecise mapping to the >=0.12 type system.
        // The change in behavior implied by this flag makes sense only for the
        // specific details of the legacy SDK type system, and are not a general
        // mechanism to avoid proper type handling in providers.
        //
        //     ====              DO NOT USE THIS              ====
        //     ==== THIS MUST BE LEFT UNSET IN ALL OTHER SDKS ====
        //     ====              DO NOT USE THIS              ====
        bool legacy_type_system = 4;
    }
}

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;
        DynamicValue provider_meta = 3;
    }
    message Response {
        DynamicValue state = 1;
        repeated Diagnostic diagnostics = 2;
    }
}
