cp transactions (the proxy part) A typical control-plane transaction will execute, with minor variations, the same 6 (plus/minus) steps as shown below: - notice a certain symmetry between the client and the server sides whetreby the control flow looks as follows: txnClientCtx => (POST to /v1/tx
(msg *apc.ActionMsg, bck *cluster.Bck, remoteHeader ...http.Header)
| 137 | |
| 138 | // create-bucket: { check non-existence -- begin -- create locally -- metasync -- commit } |
| 139 | func (p *proxy) createBucket(msg *apc.ActionMsg, bck *cluster.Bck, remoteHeader ...http.Header) error { |
| 140 | var ( |
| 141 | bucketProps *cmn.BucketProps |
| 142 | nlp = bck.GetNameLockPair() |
| 143 | bmd = p.owner.bmd.get() |
| 144 | ) |
| 145 | if bck.Props != nil { |
| 146 | bucketProps = bck.Props |
| 147 | } |
| 148 | if len(remoteHeader) != 0 && len(remoteHeader[0]) > 0 { |
| 149 | remoteProps := defaultBckProps(bckPropsArgs{bck: bck, hdr: remoteHeader[0]}) |
| 150 | if bucketProps == nil { |
| 151 | bucketProps = remoteProps |
| 152 | } else { |
| 153 | bucketProps.Versioning.Enabled = remoteProps.Versioning.Enabled // always takes precedence |
| 154 | } |
| 155 | } else if backend := bck.Backend(); backend != nil { |
| 156 | if bucketProps == nil { |
| 157 | bucketProps = defaultBckProps(bckPropsArgs{bck: bck}) |
| 158 | } |
| 159 | cloudProps, present := bmd.Get(backend) |
| 160 | debug.Assert(present) |
| 161 | bucketProps.Versioning.Enabled = cloudProps.Versioning.Enabled // always takes precedence |
| 162 | } else if bck.IsHTTP() { |
| 163 | return errors.New("creating bucket for HTTP provider is not supported") |
| 164 | } else if bck.IsCloud() { |
| 165 | return fmt.Errorf("creating bucket for %q (cloud) provider is not supported", bck.Provider) |
| 166 | } else if bucketProps == nil { |
| 167 | bucketProps = defaultBckProps(bckPropsArgs{bck: bck}) |
| 168 | } |
| 169 | |
| 170 | nlp.Lock() |
| 171 | defer nlp.Unlock() |
| 172 | |
| 173 | // 1. try add |
| 174 | if _, present := bmd.Get(bck); present { |
| 175 | return cmn.NewErrBckAlreadyExists(bck.Bucket()) |
| 176 | } |
| 177 | |
| 178 | // 2. begin |
| 179 | var ( |
| 180 | waitmsync = true // commit blocks behind metasync |
| 181 | c = p.prepTxnClient(msg, bck, waitmsync) |
| 182 | ) |
| 183 | if err := c.begin(bck); err != nil { |
| 184 | return err |
| 185 | } |
| 186 | |
| 187 | // 3. update BMD locally & metasync updated BMD |
| 188 | ctx := &bmdModifier{ |
| 189 | pre: _createBMDPre, |
| 190 | final: p._syncBMDFinal, |
| 191 | wait: waitmsync, |
| 192 | msg: &c.msg.ActionMsg, |
| 193 | txnID: c.uuid, |
| 194 | bcks: []*cluster.Bck{bck}, |
| 195 | setProps: bucketProps, |
| 196 | } |
no test coverage detected