server: Move all the top level files into cmd folder. (#2490)

This change brings a change which was done for the 'mc'
package to allow for clean repo and have a cleaner
github drop in experience.

cmd/bucket-policy.go

@@ -0,0 +1,180 @@
+/*
+ * Minio Cloud Storage, (C) 2015, 2016 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * 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 cmd
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"path"
+	"sync"
+)
+
+// Variable represents bucket policies in memory.
+var globalBucketPolicies *bucketPolicies
+
+// Global bucket policies list, policies are enforced on each bucket looking
+// through the policies here.
+type bucketPolicies struct {
+	rwMutex *sync.RWMutex
+
+	// Collection of 'bucket' policies.
+	bucketPolicyConfigs map[string]*bucketPolicy
+}
+
+// Fetch bucket policy for a given bucket.
+func (bp bucketPolicies) GetBucketPolicy(bucket string) *bucketPolicy {
+	bp.rwMutex.RLock()
+	defer bp.rwMutex.RUnlock()
+	return bp.bucketPolicyConfigs[bucket]
+}
+
+// Set a new bucket policy for a bucket, this operation will overwrite
+// any previous bucketpolicies for the bucket.
+func (bp *bucketPolicies) SetBucketPolicy(bucket string, policy *bucketPolicy) error {
+	bp.rwMutex.Lock()
+	defer bp.rwMutex.Unlock()
+	if policy == nil {
+		return errors.New("invalid argument")
+	}
+	bp.bucketPolicyConfigs[bucket] = policy
+	return nil
+}
+
+// Remove bucket policy for a bucket, from in-memory map.
+func (bp *bucketPolicies) RemoveBucketPolicy(bucket string) {
+	bp.rwMutex.Lock()
+	defer bp.rwMutex.Unlock()
+	delete(bp.bucketPolicyConfigs, bucket)
+}
+
+// Loads all bucket policies from persistent layer.
+func loadAllBucketPolicies(objAPI ObjectLayer) (policies map[string]*bucketPolicy, err error) {
+	// List buckets to proceed loading all notification configuration.
+	buckets, err := objAPI.ListBuckets()
+	if err != nil {
+		return nil, err
+	}
+	policies = make(map[string]*bucketPolicy)
+	// Loads bucket policy.
+	for _, bucket := range buckets {
+		var policy *bucketPolicy
+		policy, err = readBucketPolicy(bucket.Name, objAPI)
+		if err != nil {
+			switch err.(type) {
+			case BucketPolicyNotFound:
+				continue
+			}
+			return nil, err
+		}
+		policies[bucket.Name] = policy
+	}
+
+	// Success.
+	return policies, nil
+
+}
+
+// Intialize all bucket policies.
+func initBucketPolicies(objAPI ObjectLayer) error {
+	if objAPI == nil {
+		return errInvalidArgument
+	}
+	// Read all bucket policies.
+	policies, err := loadAllBucketPolicies(objAPI)
+	if err != nil {
+		return err
+	}
+
+	globalBucketPolicies = &bucketPolicies{
+		rwMutex:             &sync.RWMutex{},
+		bucketPolicyConfigs: policies,
+	}
+	return nil
+}
+
+// getOldBucketsConfigPath - get old buckets config path. (Only used for migrating old bucket policies)
+func getOldBucketsConfigPath() (string, error) {
+	configPath, err := getConfigPath()
+	if err != nil {
+		return "", err
+	}
+	return path.Join(configPath, "buckets"), nil
+}
+
+// readBucketPolicy - reads bucket policy for an input bucket, returns BucketPolicyNotFound
+// if bucket policy is not found. This function also parses the bucket policy into an object.
+func readBucketPolicy(bucket string, objAPI ObjectLayer) (*bucketPolicy, error) {
+	// Verify bucket is valid.
+	if !IsValidBucketName(bucket) {
+		return nil, BucketNameInvalid{Bucket: bucket}
+	}
+	policyPath := pathJoin(bucketConfigPrefix, bucket, policyJSON)
+	objInfo, err := objAPI.GetObjectInfo(minioMetaBucket, policyPath)
+	if err != nil {
+		if _, ok := err.(ObjectNotFound); ok {
+			return nil, BucketPolicyNotFound{Bucket: bucket}
+		}
+		return nil, err
+	}
+	var buffer bytes.Buffer
+	err = objAPI.GetObject(minioMetaBucket, policyPath, 0, objInfo.Size, &buffer)
+	if err != nil {
+		if _, ok := err.(ObjectNotFound); ok {
+			return nil, BucketPolicyNotFound{Bucket: bucket}
+		}
+		return nil, err
+	}
+	// Parse the saved policy.
+	var policy = &bucketPolicy{}
+	err = parseBucketPolicy(&buffer, policy)
+	if err != nil {
+		return nil, err
+
+	}
+	return policy, nil
+}
+
+// removeBucketPolicy - removes any previously written bucket policy. Returns BucketPolicyNotFound
+// if no policies are found.
+func removeBucketPolicy(bucket string, objAPI ObjectLayer) error {
+	// Verify bucket is valid.
+	if !IsValidBucketName(bucket) {
+		return BucketNameInvalid{Bucket: bucket}
+	}
+
+	policyPath := pathJoin(bucketConfigPrefix, bucket, policyJSON)
+	if err := objAPI.DeleteObject(minioMetaBucket, policyPath); err != nil {
+		if _, ok := err.(ObjectNotFound); ok {
+			return BucketPolicyNotFound{Bucket: bucket}
+		}
+		return err
+	}
+	return nil
+}
+
+// writeBucketPolicy - save all bucket policies.
+func writeBucketPolicy(bucket string, objAPI ObjectLayer, reader io.Reader, size int64) error {
+	// Verify if bucket path legal
+	if !IsValidBucketName(bucket) {
+		return BucketNameInvalid{Bucket: bucket}
+	}
+
+	policyPath := pathJoin(bucketConfigPrefix, bucket, policyJSON)
+	_, err := objAPI.PutObject(minioMetaBucket, policyPath, size, reader, nil)
+	return err
+}