12 Commits (deb91f3d3c0e988242272bb0249a5a88d1fcc907)

Author	SHA1	Message	Date
R.B. Boyer	fd1c62ee8b	connect: ensure time.Duration fields retain their human readable forms in the API (#6348) ... This applies for both config entries and the compiled discovery chain. Also omit some other config entries fields when empty.	5 years ago
R.B. Boyer	561b2fe606	connect: generate the full SNI names for discovery targets in the compiler rather than in the xds package (#6340)	5 years ago
R.B. Boyer	ae79cdab1b	connect: introduce ExternalSNI field on service-defaults (#6324) ... Compiling this will set an optional SNI field on each DiscoveryTarget. When set this value should be used for TLS connections to the instances of the target. If not set the default should be used. Setting ExternalSNI will disable mesh gateway use for that target. It also disables several service-resolver features that do not make sense for an external service.	5 years ago
R.B. Boyer	8e22d80e35	connect: fix failover through a mesh gateway to a remote datacenter (#6259) ... Failover is pushed entirely down to the data plane by creating envoy clusters and putting each successive destination in a different load assignment priority band. For example this shows that normally requests go to 1.2.3.4:8080 but when that fails they go to 6.7.8.9:8080: - name: foo load_assignment: cluster_name: foo policy: overprovisioning_factor: 100000 endpoints: - priority: 0 lb_endpoints: - endpoint: address: socket_address: address: 1.2.3.4 port_value: 8080 - priority: 1 lb_endpoints: - endpoint: address: socket_address: address: 6.7.8.9 port_value: 8080 Mesh gateways route requests based solely on the SNI header tacked onto the TLS layer. Envoy currently only lets you configure the outbound SNI header at the cluster layer. If you try to failover through a mesh gateway you ideally would configure the SNI value per endpoint, but that's not possible in envoy today. This PR introduces a simpler way around the problem for now: 1. We identify any target of failover that will use mesh gateway mode local or remote and then further isolate any resolver node in the compiled discovery chain that has a failover destination set to one of those targets. 2. For each of these resolvers we will perform a small measurement of comparative healths of the endpoints that come back from the health API for the set of primary target and serial failover targets. We walk the list of targets in order and if any endpoint is healthy we return that target, otherwise we move on to the next target. 3. The CDS and EDS endpoints both perform the measurements in (2) for the affected resolver nodes. 4. For CDS this measurement selects which TLS SNI field to use for the cluster (note the cluster is always going to be named for the primary target) 5. For EDS this measurement selects which set of endpoints will populate the cluster. Priority tiered failover is ignored. One of the big downsides to this approach to failover is that the failover detection and correction is going to be controlled by consul rather than deferring that entirely to the data plane as with the prior version. This also means that we are bound to only failover using official health signals and cannot make use of data plane signals like outlier detection to affect failover. In this specific scenario the lack of data plane signals is ok because the effectiveness is already muted by the fact that the ultimate destination endpoints will have their data plane signals scrambled when they pass through the mesh gateway wrapper anyway so we're not losing much. Another related fix is that we now use the endpoint health from the underlying service, not the health of the gateway (regardless of failover mode).	5 years ago
R.B. Boyer	c395affc93	connect: expose an API endpoint to compile the discovery chain (#6248) ... In addition to exposing compilation over the API cleaned up the structures that would be exchanged to be cleaner and easier to support and understand. Also removed ability to configure the envoy OverprovisioningFactor.	5 years ago
R.B. Boyer	dcb609af83	connect: detect and prevent circular discovery chain references (#6246)	5 years ago
R.B. Boyer	f02924fafe	connect: simplify the compiled discovery chain data structures (#6242) ... This should make them better for sending over RPC or the API. Instead of a chain implemented explicitly like a linked list (nodes holding pointers to other nodes) instead switch to a flat map of named nodes with nodes linking other other nodes by name. The shipped structure is just a map and a string to indicate which key to start from. Other changes: * inline the compiler option InferDefaults as true * introduce compiled target config to avoid needing to send back additional maps of Resolvers; future target-specific compiled state can go here * move compiled MeshGateway out of the Resolver and into the TargetConfig where it makes more sense.	5 years ago
R.B. Boyer	6393edba53	connect: reconcile how upstream configuration works with discovery chains (#6225) ... * connect: reconcile how upstream configuration works with discovery chains The following upstream config fields for connect sidecars sanely integrate into discovery chain resolution: - Destination Namespace/Datacenter: Compilation occurs locally but using different default values for namespaces and datacenters. The xDS clusters that are created are named as they normally would be. - Mesh Gateway Mode (single upstream): If set this value overrides any value computed for any resolver for the entire discovery chain. The xDS clusters that are created may be named differently (see below). - Mesh Gateway Mode (whole sidecar): If set this value overrides any value computed for any resolver for the entire discovery chain. If this is specifically overridden for a single upstream this value is ignored in that case. The xDS clusters that are created may be named differently (see below). - Protocol (in opaque config): If set this value overrides the value computed when evaluating the entire discovery chain. If the normal chain would be TCP or if this override is set to TCP then the result is that we explicitly disable L7 Routing and Splitting. The xDS clusters that are created may be named differently (see below). - Connect Timeout (in opaque config): If set this value overrides the value for any resolver in the entire discovery chain. The xDS clusters that are created may be named differently (see below). If any of the above overrides affect the actual result of compiling the discovery chain (i.e. "tcp" becomes "grpc" instead of being a no-op override to "tcp") then the relevant parameters are hashed and provided to the xDS layer as a prefix for use in naming the Clusters. This is to ensure that if one Upstream discovery chain has no overrides and tangentially needs a cluster named "api.default.XXX", and another Upstream does have overrides for "api.default.XXX" that they won't cross-pollinate against the operator's wishes. Fixes #6159	5 years ago
R.B. Boyer	e039dfd7f8	connect: rework how the service resolver subset OnlyPassing flag works (#6173) ... The main change is that we no longer filter service instances by health, preferring instead to render all results down into EDS endpoints in envoy and merely label the endpoints as HEALTHY or UNHEALTHY. When OnlyPassing is set to true we will force consul checks in a 'warning' state to render as UNHEALTHY in envoy. Fixes #6171	5 years ago
R.B. Boyer	9138a97054	Fix bug in service-resolver redirects if the destination uses a default resolver. (#6122) ... Also: - add back an internal http endpoint to dump a compiled discovery chain for debugging purposes Before the CompiledDiscoveryChain.IsDefault() method would test: - is this chain just one resolver step? - is that resolver step just the default? But what I forgot to test: - is that resolver step for the same service that the chain represents? This last point is important because if you configured just one config entry: kind = "service-resolver" name = "web" redirect { service = "other" } and requested the chain for "web" you'd get back a **default** resolver for "other". In the xDS code the IsDefault() method is used to determine if this chain is "empty". If it is then we use the pre-discovery-chain logic that just uses data embedded in the Upstream object (and still lets the escape hatches function). In the example above that means certain parts of the xDS code were going to try referencing a cluster named "web..." despite the other parts of the xDS code maintaining clusters named "other...".	5 years ago
R.B. Boyer	4bdb690a25	activate most discovery chain features in xDS for envoy (#6024)	5 years ago
R.B. Boyer	6a52f9f9fb	initial version of L7 config entry compiler (#5994) ... With this you should be able to fetch all of the relevant discovery chain config entries from the state store in one query and then feed them into the compiler outside of a transaction. There are a lot of TODOs scattered through here, but they're mostly around handling fun edge cases and can be deferred until more of the plumbing works completely.	5 years ago