Holger Hildebrandt | fa07499 | 2020-03-27 15:42:06 +0000 | [diff] [blame^] | 1 | package api |
| 2 | |
| 3 | import ( |
| 4 | "encoding/json" |
| 5 | "fmt" |
| 6 | "time" |
| 7 | ) |
| 8 | |
| 9 | // DiscoveryChain can be used to query the discovery-chain endpoints |
| 10 | type DiscoveryChain struct { |
| 11 | c *Client |
| 12 | } |
| 13 | |
| 14 | // DiscoveryChain returns a handle to the discovery-chain endpoints |
| 15 | func (c *Client) DiscoveryChain() *DiscoveryChain { |
| 16 | return &DiscoveryChain{c} |
| 17 | } |
| 18 | |
| 19 | func (d *DiscoveryChain) Get(name string, opts *DiscoveryChainOptions, q *QueryOptions) (*DiscoveryChainResponse, *QueryMeta, error) { |
| 20 | if name == "" { |
| 21 | return nil, nil, fmt.Errorf("Name parameter must not be empty") |
| 22 | } |
| 23 | |
| 24 | method := "GET" |
| 25 | if opts != nil && opts.requiresPOST() { |
| 26 | method = "POST" |
| 27 | } |
| 28 | |
| 29 | r := d.c.newRequest(method, fmt.Sprintf("/v1/discovery-chain/%s", name)) |
| 30 | r.setQueryOptions(q) |
| 31 | |
| 32 | if opts != nil { |
| 33 | if opts.EvaluateInDatacenter != "" { |
| 34 | r.params.Set("compile-dc", opts.EvaluateInDatacenter) |
| 35 | } |
| 36 | // TODO(namespaces): handle possible EvaluateInNamespace here |
| 37 | } |
| 38 | |
| 39 | if method == "POST" { |
| 40 | r.obj = opts |
| 41 | } |
| 42 | |
| 43 | rtt, resp, err := requireOK(d.c.doRequest(r)) |
| 44 | if err != nil { |
| 45 | return nil, nil, err |
| 46 | } |
| 47 | defer resp.Body.Close() |
| 48 | |
| 49 | qm := &QueryMeta{} |
| 50 | parseQueryMeta(resp, qm) |
| 51 | qm.RequestTime = rtt |
| 52 | |
| 53 | var out DiscoveryChainResponse |
| 54 | |
| 55 | if err := decodeBody(resp, &out); err != nil { |
| 56 | return nil, nil, err |
| 57 | } |
| 58 | |
| 59 | return &out, qm, nil |
| 60 | } |
| 61 | |
| 62 | type DiscoveryChainOptions struct { |
| 63 | EvaluateInDatacenter string `json:"-"` |
| 64 | |
| 65 | // OverrideMeshGateway allows for the mesh gateway setting to be overridden |
| 66 | // for any resolver in the compiled chain. |
| 67 | OverrideMeshGateway MeshGatewayConfig `json:",omitempty"` |
| 68 | |
| 69 | // OverrideProtocol allows for the final protocol for the chain to be |
| 70 | // altered. |
| 71 | // |
| 72 | // - If the chain ordinarily would be TCP and an L7 protocol is passed here |
| 73 | // the chain will not include Routers or Splitters. |
| 74 | // |
| 75 | // - If the chain ordinarily would be L7 and TCP is passed here the chain |
| 76 | // will not include Routers or Splitters. |
| 77 | OverrideProtocol string `json:",omitempty"` |
| 78 | |
| 79 | // OverrideConnectTimeout allows for the ConnectTimeout setting to be |
| 80 | // overridden for any resolver in the compiled chain. |
| 81 | OverrideConnectTimeout time.Duration `json:",omitempty"` |
| 82 | } |
| 83 | |
| 84 | func (o *DiscoveryChainOptions) requiresPOST() bool { |
| 85 | if o == nil { |
| 86 | return false |
| 87 | } |
| 88 | return o.OverrideMeshGateway.Mode != "" || |
| 89 | o.OverrideProtocol != "" || |
| 90 | o.OverrideConnectTimeout != 0 |
| 91 | } |
| 92 | |
| 93 | type DiscoveryChainResponse struct { |
| 94 | Chain *CompiledDiscoveryChain |
| 95 | } |
| 96 | |
| 97 | type CompiledDiscoveryChain struct { |
| 98 | ServiceName string |
| 99 | Namespace string |
| 100 | Datacenter string |
| 101 | |
| 102 | // CustomizationHash is a unique hash of any data that affects the |
| 103 | // compilation of the discovery chain other than config entries or the |
| 104 | // name/namespace/datacenter evaluation criteria. |
| 105 | // |
| 106 | // If set, this value should be used to prefix/suffix any generated load |
| 107 | // balancer data plane objects to avoid sharing customized and |
| 108 | // non-customized versions. |
| 109 | CustomizationHash string |
| 110 | |
| 111 | // Protocol is the overall protocol shared by everything in the chain. |
| 112 | Protocol string |
| 113 | |
| 114 | // StartNode is the first key into the Nodes map that should be followed |
| 115 | // when walking the discovery chain. |
| 116 | StartNode string |
| 117 | |
| 118 | // Nodes contains all nodes available for traversal in the chain keyed by a |
| 119 | // unique name. You can walk this by starting with StartNode. |
| 120 | // |
| 121 | // NOTE: The names should be treated as opaque values and are only |
| 122 | // guaranteed to be consistent within a single compilation. |
| 123 | Nodes map[string]*DiscoveryGraphNode |
| 124 | |
| 125 | // Targets is a list of all targets used in this chain. |
| 126 | // |
| 127 | // NOTE: The names should be treated as opaque values and are only |
| 128 | // guaranteed to be consistent within a single compilation. |
| 129 | Targets map[string]*DiscoveryTarget |
| 130 | } |
| 131 | |
| 132 | const ( |
| 133 | DiscoveryGraphNodeTypeRouter = "router" |
| 134 | DiscoveryGraphNodeTypeSplitter = "splitter" |
| 135 | DiscoveryGraphNodeTypeResolver = "resolver" |
| 136 | ) |
| 137 | |
| 138 | // DiscoveryGraphNode is a single node in the compiled discovery chain. |
| 139 | type DiscoveryGraphNode struct { |
| 140 | Type string |
| 141 | Name string // this is NOT necessarily a service |
| 142 | |
| 143 | // fields for Type==router |
| 144 | Routes []*DiscoveryRoute |
| 145 | |
| 146 | // fields for Type==splitter |
| 147 | Splits []*DiscoverySplit |
| 148 | |
| 149 | // fields for Type==resolver |
| 150 | Resolver *DiscoveryResolver |
| 151 | } |
| 152 | |
| 153 | // compiled form of ServiceRoute |
| 154 | type DiscoveryRoute struct { |
| 155 | Definition *ServiceRoute |
| 156 | NextNode string |
| 157 | } |
| 158 | |
| 159 | // compiled form of ServiceSplit |
| 160 | type DiscoverySplit struct { |
| 161 | Weight float32 |
| 162 | NextNode string |
| 163 | } |
| 164 | |
| 165 | // compiled form of ServiceResolverConfigEntry |
| 166 | type DiscoveryResolver struct { |
| 167 | Default bool |
| 168 | ConnectTimeout time.Duration |
| 169 | Target string |
| 170 | Failover *DiscoveryFailover |
| 171 | } |
| 172 | |
| 173 | func (r *DiscoveryResolver) MarshalJSON() ([]byte, error) { |
| 174 | type Alias DiscoveryResolver |
| 175 | exported := &struct { |
| 176 | ConnectTimeout string `json:",omitempty"` |
| 177 | *Alias |
| 178 | }{ |
| 179 | ConnectTimeout: r.ConnectTimeout.String(), |
| 180 | Alias: (*Alias)(r), |
| 181 | } |
| 182 | if r.ConnectTimeout == 0 { |
| 183 | exported.ConnectTimeout = "" |
| 184 | } |
| 185 | |
| 186 | return json.Marshal(exported) |
| 187 | } |
| 188 | |
| 189 | func (r *DiscoveryResolver) UnmarshalJSON(data []byte) error { |
| 190 | type Alias DiscoveryResolver |
| 191 | aux := &struct { |
| 192 | ConnectTimeout string |
| 193 | *Alias |
| 194 | }{ |
| 195 | Alias: (*Alias)(r), |
| 196 | } |
| 197 | if err := json.Unmarshal(data, &aux); err != nil { |
| 198 | return err |
| 199 | } |
| 200 | var err error |
| 201 | if aux.ConnectTimeout != "" { |
| 202 | if r.ConnectTimeout, err = time.ParseDuration(aux.ConnectTimeout); err != nil { |
| 203 | return err |
| 204 | } |
| 205 | } |
| 206 | return nil |
| 207 | } |
| 208 | |
| 209 | // compiled form of ServiceResolverFailover |
| 210 | type DiscoveryFailover struct { |
| 211 | Targets []string |
| 212 | } |
| 213 | |
| 214 | // DiscoveryTarget represents all of the inputs necessary to use a resolver |
| 215 | // config entry to execute a catalog query to generate a list of service |
| 216 | // instances during discovery. |
| 217 | type DiscoveryTarget struct { |
| 218 | ID string |
| 219 | |
| 220 | Service string |
| 221 | ServiceSubset string |
| 222 | Namespace string |
| 223 | Datacenter string |
| 224 | |
| 225 | MeshGateway MeshGatewayConfig |
| 226 | Subset ServiceResolverSubset |
| 227 | External bool |
| 228 | SNI string |
| 229 | Name string |
| 230 | } |