Merge pull request #176 from sapcc/liquid-client

liquidapi: add type Client

liquidapi/client.go

@@ -0,0 +1,130 @@
+/*******************************************************************************
+*
+* Copyright 2024 SAP SE
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You should have received a copy of the License along with this
+* program. If not, you may obtain a copy of the License at
+*
+*     http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*
+*******************************************************************************/
+
+package liquidapi
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+
+	"github.com/gophercloud/gophercloud/v2"
+	"github.com/sapcc/go-api-declarations/liquid"
+)
+
+// Client provides structured access to a LIQUID API.
+type Client struct {
+	gophercloud.ServiceClient
+}
+
+// ClientOpts contains additional options for NewClient().
+type ClientOpts struct {
+	// The service type of the liquid in the Keystone catalog.
+	// Required if EndpointOverride is not given.
+	ServiceType string
+
+	// Skips inspecting the Keystone catalog and assumes that the liquid's API is
+	// located at this base URL. Required if ServiceType is not given.
+	EndpointOverride string
+}
+
+// NewClient creates a Client for interacting with a liquid.
+func NewClient(client *gophercloud.ProviderClient, endpointOpts gophercloud.EndpointOpts, opts ClientOpts) (*Client, error) {
+	if opts.ServiceType == "" || opts.EndpointOverride == "" {
+		return nil, errors.New("either ServiceType or EndpointOverride needs to be given in liquidapi.NewClient()")
+	}
+
+	endpoint := opts.EndpointOverride
+	if endpoint == "" {
+		endpointOpts.ApplyDefaults(opts.ServiceType)
+		var err error
+		endpoint, err = client.EndpointLocator(endpointOpts)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if opts.ServiceType == "" {
+		opts.ServiceType = "liquid"
+	}
+	return &Client{
+		ServiceClient: gophercloud.ServiceClient{
+			ProviderClient: client,
+			Endpoint:       endpoint,
+			Type:           opts.ServiceType,
+		},
+	}, nil
+}
+
+// GetInfo executes GET /v1/info.
+func (c *Client) GetInfo(ctx context.Context) (result liquid.ServiceInfo, err error) {
+	url := c.ServiceURL("v1", "info")
+	opts := gophercloud.RequestOpts{KeepResponseBody: true}
+	resp, err := c.Get(ctx, url, nil, &opts)
+	if err == nil {
+		err = parseLiquidResponse(resp, &result)
+	}
+	return
+}
+
+// GetCapacityReport executes POST /v1/report-capacity.
+func (c *Client) GetCapacityReport(ctx context.Context, req liquid.ServiceCapacityRequest) (result liquid.ServiceCapacityReport, err error) {
+	url := c.ServiceURL("v1", "report-capacity")
+	opts := gophercloud.RequestOpts{KeepResponseBody: true, OkCodes: []int{http.StatusOK}}
+	resp, err := c.Post(ctx, url, req, nil, &opts)
+	if err == nil {
+		err = parseLiquidResponse(resp, &result)
+	}
+	return
+}
+
+// GetUsageReport executes POST /v1/projects/:uuid/report-usage.
+func (c *Client) GetUsageReport(ctx context.Context, projectUUID string, req liquid.ServiceUsageRequest) (result liquid.ServiceUsageReport, err error) {
+	url := c.ServiceURL("v1", "projects", projectUUID, "report-usage")
+	opts := gophercloud.RequestOpts{KeepResponseBody: true, OkCodes: []int{http.StatusOK}}
+	resp, err := c.Post(ctx, url, req, nil, &opts)
+	if err == nil {
+		err = parseLiquidResponse(resp, &result)
+	}
+	return
+}
+
+// PutQuota executes PUT /v1/projects/:uuid/quota.
+func (c *Client) PutQuota(ctx context.Context, projectUUID string, req liquid.ServiceQuotaRequest) (err error) {
+	url := c.ServiceURL("v1", "projects", projectUUID, "quota")
+	opts := gophercloud.RequestOpts{KeepResponseBody: true, OkCodes: []int{http.StatusNoContent}}
+	_, err = c.Put(ctx, url, req, nil, &opts) //nolint:bodyclose // either the response is 204 and does not have a body, or it's an error and Gophercloud does a ReadAll() internally
+	return
+}
+
+// We do not use the standard response body parsing from Gophercloud
+// because we want to be strict and DisallowUnknownFields().
+func parseLiquidResponse(resp *http.Response, result any) error {
+	defer resp.Body.Close()
+	dec := json.NewDecoder(resp.Body)
+	dec.DisallowUnknownFields()
+	err := dec.Decode(&result)
+	if err != nil {
+		return fmt.Errorf("could not parse response body from %s %s: %w",
+			resp.Request.Method, resp.Request.URL.String(), err)
+	}
+	return nil
+}

liquidapi/liquidapi.go

@@ -21,6 +21,11 @@
 // API and nothing else. The application will only have to provide a type that
 // implements the Logic interface. Then it can call Run() on an instance of it
 // to parse configuration, connect to OpenStack and run the HTTP server.
+//
+// Ref: <https://pkg.go.dev/github.com/sapcc/go-api-declarations/liquid>
+//
+// This package also provides a Gophercloud-based Client for talking to the
+// LIQUID API. Realistically, only Limes and limesctl will need this though. :)
 package liquidapi
 
 import (