package structs import ( "strconv" "github.com/hashicorp/consul/agent/cache" "github.com/hashicorp/consul/types" "github.com/mitchellh/hashstructure" ) // QueryDatacenterOptions sets options about how we fail over if there are no // healthy nodes in the local datacenter. type QueryDatacenterOptions struct { // NearestN is set to the number of remote datacenters to try, based on // network coordinates. NearestN int // Datacenters is a fixed list of datacenters to try after NearestN. We // never try a datacenter multiple times, so those are subtracted from // this list before proceeding. Datacenters []string } // QueryDNSOptions controls settings when query results are served over DNS. type QueryDNSOptions struct { // TTL is the time to live for the served DNS results. TTL string } // ServiceQuery is used to query for a set of healthy nodes offering a specific // service. type ServiceQuery struct { // Service is the service to query. Service string // Failover controls what we do if there are no healthy nodes in the // local datacenter. Failover QueryDatacenterOptions // If OnlyPassing is true then we will only include nodes with passing // health checks (critical AND warning checks will cause a node to be // discarded) OnlyPassing bool // IgnoreCheckIDs is an optional list of health check IDs to ignore when // considering which nodes are healthy. It is useful as an emergency measure // to temporarily override some health check that is producing false negatives // for example. IgnoreCheckIDs []types.CheckID // Near allows the query to always prefer the node nearest the given // node. If the node does not exist, results are returned in their // normal randomly-shuffled order. Supplying the magic "_agent" value // is supported to sort near the agent which initiated the request. Near string // Tags are a set of required and/or disallowed tags. If a tag is in // this list it must be present. If the tag is preceded with "!" then // it is disallowed. Tags []string // NodeMeta is a map of required node metadata fields. If a key/value // pair is in this map it must be present on the node in order for the // service entry to be returned. NodeMeta map[string]string // Connect if true will filter the prepared query results to only // include Connect-capable services. These include both native services // and proxies for matching services. Note that if a proxy matches, // the constraints in the query above (Near, OnlyPassing, etc.) apply // to the _proxy_ and not the service being proxied. In practice, proxies // should be directly next to their services so this isn't an issue. Connect bool } const ( // QueryTemplateTypeNamePrefixMatch uses the Name field of the query as // a prefix to select the template. QueryTemplateTypeNamePrefixMatch = "name_prefix_match" ) // QueryTemplateOptions controls settings if this query is a template. type QueryTemplateOptions struct { // Type, if non-empty, means that this query is a template. This is // set to one of the QueryTemplateType* constants above. Type string // Regexp is an optional regular expression to use to parse the full // name, once the prefix match has selected a template. This can be // used to extract parts of the name and choose a service name, set // tags, etc. Regexp string // RemoveEmptyTags, if true, removes empty tags from matched tag list RemoveEmptyTags bool } // PreparedQuery defines a complete prepared query, and is the structure we // maintain in the state store. type PreparedQuery struct { // ID is this UUID-based ID for the query, always generated by Consul. ID string // Name is an optional friendly name for the query supplied by the // user. NOTE - if this feature is used then it will reduce the security // of any read ACL associated with this query/service since this name // can be used to locate nodes with supplying any ACL. Name string // Session is an optional session to tie this query's lifetime to. If // this is omitted then the query will not expire. Session string // Token is the ACL token used when the query was created, and it is // used when a query is subsequently executed. This token, or a token // with management privileges, must be used to change the query later. Token string // Template is used to configure this query as a template, which will // respond to queries based on the Name, and then will be rendered // before it is executed. Template QueryTemplateOptions // Service defines a service query (leaving things open for other types // later). Service ServiceQuery // DNS has options that control how the results of this query are // served over DNS. DNS QueryDNSOptions RaftIndex } // GetACLPrefix returns the prefix to look up the prepared_query ACL policy for // this query, and whether the prefix applies to this query. You always need to // check the ok value before using the prefix. func (pq *PreparedQuery) GetACLPrefix() (string, bool) { if pq.Name != "" || pq.Template.Type != "" { return pq.Name, true } return "", false } type PreparedQueries []*PreparedQuery type IndexedPreparedQueries struct { Queries PreparedQueries QueryMeta } type PreparedQueryOp string const ( PreparedQueryCreate PreparedQueryOp = "create" PreparedQueryUpdate PreparedQueryOp = "update" PreparedQueryDelete PreparedQueryOp = "delete" ) // QueryRequest is used to create or change prepared queries. type PreparedQueryRequest struct { // Datacenter is the target this request is intended for. Datacenter string // Op is the operation to apply. Op PreparedQueryOp // Query is the query itself. Query *PreparedQuery // WriteRequest holds the ACL token to go along with this request. WriteRequest } // RequestDatacenter returns the datacenter for a given request. func (q *PreparedQueryRequest) RequestDatacenter() string { return q.Datacenter } // PreparedQuerySpecificRequest is used to get information about a prepared // query. type PreparedQuerySpecificRequest struct { // Datacenter is the target this request is intended for. Datacenter string // QueryID is the ID of a query. QueryID string // QueryOptions (unfortunately named here) controls the consistency // settings for the query lookup itself, as well as the service lookups. QueryOptions } // RequestDatacenter returns the datacenter for a given request. func (q *PreparedQuerySpecificRequest) RequestDatacenter() string { return q.Datacenter } // PreparedQueryExecuteRequest is used to execute a prepared query. type PreparedQueryExecuteRequest struct { // Datacenter is the target this request is intended for. Datacenter string // QueryIDOrName is the ID of a query _or_ the name of one, either can // be provided. QueryIDOrName string // Limit will trim the resulting list down to the given limit. Limit int // Connect will force results to be Connect-enabled nodes for the // matching services. This is equivalent in semantics exactly to // setting "Connect" in the query template itself, but allows callers // to use any prepared query in a Connect setting. Connect bool // Source is used to sort the results relative to a given node using // network coordinates. Source QuerySource // Agent is used to carry around a reference to the agent which initiated // the execute request. Used to distance-sort relative to the local node. Agent QuerySource // QueryOptions (unfortunately named here) controls the consistency // settings for the query lookup itself, as well as the service lookups. QueryOptions } // RequestDatacenter returns the datacenter for a given request. func (q *PreparedQueryExecuteRequest) RequestDatacenter() string { return q.Datacenter } // CacheInfo implements cache.Request allowing requests to be cached on agent. func (q *PreparedQueryExecuteRequest) CacheInfo() cache.RequestInfo { info := cache.RequestInfo{ Token: q.Token, Datacenter: q.Datacenter, MinIndex: q.MinQueryIndex, Timeout: q.MaxQueryTime, MaxAge: q.MaxAge, MustRevalidate: q.MustRevalidate, } // To calculate the cache key we hash over all the fields that affect the // output other than Datacenter and Token which are dealt with in the cache // framework already. Note the order here is important for the outcome - if we // ever care about cache-invalidation on updates e.g. because we persist // cached results, we need to be careful we maintain the same order of fields // here. We could alternatively use `hash:set` struct tag on an anonymous // struct to make it more robust if it becomes significant. v, err := hashstructure.Hash([]interface{}{ q.QueryIDOrName, q.Limit, q.Connect, }, nil) if err == nil { // If there is an error, we don't set the key. A blank key forces // no cache for this request so the request is forwarded directly // to the server. info.Key = strconv.FormatUint(v, 10) } return info } // PreparedQueryExecuteRemoteRequest is used when running a local query in a // remote datacenter. type PreparedQueryExecuteRemoteRequest struct { // Datacenter is the target this request is intended for. Datacenter string // Query is a copy of the query to execute. We have to ship the entire // query over since it won't be present in the remote state store. Query PreparedQuery // Limit will trim the resulting list down to the given limit. Limit int // Connect is the same as ExecuteRequest. Connect bool // QueryOptions (unfortunately named here) controls the consistency // settings for the the service lookups. QueryOptions } // RequestDatacenter returns the datacenter for a given request. func (q *PreparedQueryExecuteRemoteRequest) RequestDatacenter() string { return q.Datacenter } // PreparedQueryExecuteResponse has the results of executing a query. type PreparedQueryExecuteResponse struct { // Service is the service that was queried. Service string // Nodes has the nodes that were output by the query. Nodes CheckServiceNodes // DNS has the options for serving these results over DNS. DNS QueryDNSOptions // Datacenter is the datacenter that these results came from. Datacenter string // Failovers is a count of how many times we had to query a remote // datacenter. Failovers int // QueryMeta has freshness information about the query. QueryMeta } // PreparedQueryExplainResponse has the results when explaining a query/ type PreparedQueryExplainResponse struct { // Query has the fully-rendered query. Query PreparedQuery // QueryMeta has freshness information about the query. QueryMeta }