org.opendaylight.restconf.server.spi.ApiPathNormalizer Maven / Gradle / Ivy
/*
* Copyright (c) 2016 Cisco Systems, Inc. and others. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 which accompanies this distribution,
* and is available at http://www.eclipse.org/legal/epl-v10.html
*/
package org.opendaylight.restconf.server.spi;
import static com.google.common.base.Verify.verify;
import static com.google.common.base.Verify.verifyNotNull;
import static java.util.Objects.requireNonNull;
import com.google.common.base.VerifyException;
import com.google.common.collect.ImmutableMap;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.eclipse.jdt.annotation.NonNull;
import org.opendaylight.restconf.api.ApiPath;
import org.opendaylight.restconf.api.ApiPath.ListInstance;
import org.opendaylight.restconf.api.ApiPath.Step;
import org.opendaylight.restconf.server.api.DatabindContext;
import org.opendaylight.restconf.server.api.DatabindPath;
import org.opendaylight.restconf.server.api.DatabindPath.Action;
import org.opendaylight.restconf.server.api.DatabindPath.Data;
import org.opendaylight.restconf.server.api.DatabindPath.InstanceReference;
import org.opendaylight.restconf.server.api.DatabindPath.Rpc;
import org.opendaylight.restconf.server.api.ServerException;
import org.opendaylight.yangtools.yang.common.ErrorTag;
import org.opendaylight.yangtools.yang.common.ErrorType;
import org.opendaylight.yangtools.yang.common.QName;
import org.opendaylight.yangtools.yang.common.QNameModule;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeWithValue;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
import org.opendaylight.yangtools.yang.data.util.DataSchemaContext;
import org.opendaylight.yangtools.yang.data.util.DataSchemaContext.PathMixin;
import org.opendaylight.yangtools.yang.model.api.ActionNodeContainer;
import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
import org.opendaylight.yangtools.yang.model.api.LeafListSchemaNode;
import org.opendaylight.yangtools.yang.model.api.ListSchemaNode;
import org.opendaylight.yangtools.yang.model.api.TypedDataSchemaNode;
import org.opendaylight.yangtools.yang.model.api.stmt.RpcEffectiveStatement;
import org.opendaylight.yangtools.yang.model.api.stmt.SchemaTreeEffectiveStatement;
import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack;
/**
* Utility for normalizing {@link ApiPath}s. An {@link ApiPath} can represent a number of different constructs, as
* denoted to in the {@link DatabindPath} interface hierarchy.
*
*
* This process is governed by
* RFC8040, section 3.5.3. The URI provides the
* equivalent of NETCONF XML filter encoding, with data values being escaped RFC7891 strings.
*/
public final class ApiPathNormalizer implements Insert.PointNormalizer {
private final @NonNull DatabindContext databind;
public ApiPathNormalizer(final DatabindContext databind) {
this.databind = requireNonNull(databind);
}
public DatabindContext databind() {
return databind;
}
public @NonNull DatabindPath normalizePath(final ApiPath apiPath) throws ServerException {
final var it = apiPath.steps().iterator();
if (!it.hasNext()) {
return new Data(databind);
}
// First step is somewhat special:
// - it has to contain a module qualifier
// - it has to consider RPCs, for which we need SchemaContext
//
// We therefore peel that first iteration here and not worry about those details in further iterations
final var firstStep = it.next();
final var firstModule = firstStep.module();
if (firstModule == null) {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.MALFORMED_MESSAGE,
"First member must use namespace-qualified form, '%s' does not", firstStep.identifier());
}
var namespace = resolveNamespace(firstModule);
var step = firstStep;
var qname = step.identifier().bindTo(namespace);
// We go through more modern APIs here to get this special out of the way quickly
final var modelContext = databind.modelContext();
final var optRpc = modelContext.findModuleStatement(namespace).orElseThrow()
.findSchemaTreeNode(RpcEffectiveStatement.class, qname);
if (optRpc.isPresent()) {
final var rpc = optRpc.orElseThrow();
// We have found an RPC match,
if (it.hasNext()) {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.MALFORMED_MESSAGE,
"First step in the path resolves to RPC '%s' and therefore it must be the only step present",
qname);
}
if (step instanceof ListInstance) {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.MALFORMED_MESSAGE,
"First step in the path resolves to RPC '%s' and therefore it must not contain key values", qname);
}
final var stack = SchemaInferenceStack.of(modelContext);
final var stmt = stack.enterSchemaTree(rpc.argument());
verify(rpc.equals(stmt), "Expecting %s, inferred %s", rpc, stmt);
return new Rpc(databind, stack.toInference(), rpc);
}
return normalizeSteps(SchemaInferenceStack.of(modelContext), databind.schemaTree().getRoot(), List.of(),
namespace, firstStep, it);
}
@NonNull DatabindPath normalizeSteps(final SchemaInferenceStack stack, final @NonNull DataSchemaContext rootNode,
final @NonNull List pathPrefix, final @NonNull QNameModule firstNamespace,
final @NonNull Step firstStep, final Iterator<@NonNull Step> it) throws ServerException {
var parentNode = rootNode;
var namespace = firstNamespace;
var step = firstStep;
var qname = step.identifier().bindTo(namespace);
final var path = new ArrayList<>(pathPrefix);
while (true) {
final var parentSchema = parentNode.dataSchemaNode();
if (parentSchema instanceof ActionNodeContainer actionParent) {
final var optAction = actionParent.findAction(qname);
if (optAction.isPresent()) {
final var action = optAction.orElseThrow();
if (it.hasNext()) {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.MALFORMED_MESSAGE,
"Request path resolves to action '%s' and therefore it must not continue past it", qname);
}
if (step instanceof ListInstance) {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.MALFORMED_MESSAGE,
"Request path resolves to action '%s' and therefore it must not contain key values", qname);
}
final var stmt = stack.enterSchemaTree(qname);
final var actionStmt = action.asEffectiveStatement();
verify(actionStmt.equals(stmt), "Expecting %s, inferred %s", actionStmt, stmt);
return new Action(databind, stack.toInference(), YangInstanceIdentifier.of(path), actionStmt);
}
}
// Resolve the child step with respect to data schema tree
final var found = parentNode instanceof DataSchemaContext.Composite composite
? composite.enterChild(stack, qname) : null;
if (found == null) {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.DATA_MISSING, "Schema for '%s' not found",
qname);
}
// Now add all mixins encountered to the path
var childNode = found;
while (childNode instanceof PathMixin currentMixin) {
path.add(currentMixin.mixinPathStep());
childNode = verifyNotNull(currentMixin.enterChild(stack, qname),
"Mixin %s is missing child for %s while resolving %s", childNode, qname, found);
}
final PathArgument pathArg;
if (step instanceof ListInstance listStep) {
final var values = listStep.keyValues();
final var schema = childNode.dataSchemaNode();
if (schema instanceof ListSchemaNode listSchema) {
pathArg = prepareNodeWithPredicates(stack, qname, listSchema, values);
} else if (schema instanceof LeafListSchemaNode leafListSchema) {
if (values.size() != 1) {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.BAD_ATTRIBUTE,
"Entry '%s' requires one value predicate.", qname);
}
pathArg = new NodeWithValue<>(qname, parserJsonValue(stack, leafListSchema, values.get(0)));
} else {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.MISSING_ATTRIBUTE,
"Entry '%s' does not take a key or value predicate.", qname);
}
} else {
if (childNode.dataSchemaNode() instanceof ListSchemaNode list && !list.getKeyDefinition().isEmpty()) {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.MISSING_ATTRIBUTE,
"Entry '%s' requires key or value predicate to be present.", qname);
}
pathArg = childNode.getPathStep();
}
path.add(pathArg);
if (!it.hasNext()) {
return new Data(databind, stack.toInference(), YangInstanceIdentifier.of(path), childNode);
}
parentNode = childNode;
step = it.next();
final var module = step.module();
if (module != null) {
namespace = resolveNamespace(module);
}
qname = step.identifier().bindTo(namespace);
}
}
public @NonNull Data normalizeDataPath(final ApiPath apiPath) throws ServerException {
final var path = normalizePath(apiPath);
if (path instanceof Data dataPath) {
return dataPath;
}
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.DATA_MISSING, "Point '%s' resolves to non-data %s",
apiPath, path);
}
@Override
public PathArgument normalizePoint(final ApiPath value) throws ServerException {
final var path = normalizePath(value);
if (path instanceof Data dataPath) {
final var lastArg = dataPath.instance().getLastPathArgument();
if (lastArg != null) {
return lastArg;
}
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.DATA_MISSING,
"Point '%s' resolves to an empty path", value);
}
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.DATA_MISSING, "Point '%s' resolves to non-data %s",
value, path);
}
public @NonNull Rpc normalizeRpcPath(final ApiPath apiPath) throws ServerException {
final var steps = apiPath.steps();
return switch (steps.size()) {
case 0 -> throw new ServerException(ErrorType.PROTOCOL, ErrorTag.DATA_MISSING, "RPC name must be present");
case 1 -> normalizeRpcPath(steps.get(0));
default -> throw new ServerException(ErrorType.PROTOCOL, ErrorTag.DATA_MISSING,
"%s does not refer to an RPC", apiPath);
};
}
public @NonNull Rpc normalizeRpcPath(final ApiPath.Step step) throws ServerException {
final var firstModule = step.module();
if (firstModule == null) {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.MALFORMED_MESSAGE,
"First member must use namespace-qualified form, '%s' does not", step.identifier());
}
final var namespace = resolveNamespace(firstModule);
final var qname = step.identifier().bindTo(namespace);
final var stack = SchemaInferenceStack.of(databind.modelContext());
final SchemaTreeEffectiveStatement stmt;
try {
stmt = stack.enterSchemaTree(qname);
} catch (IllegalArgumentException e) {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.DATA_MISSING, qname + " does not refer to an RPC",
e);
}
if (stmt instanceof RpcEffectiveStatement rpc) {
return new Rpc(databind, stack.toInference(), rpc);
}
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.DATA_MISSING, "%s does not refer to an RPC", qname);
}
public @NonNull InstanceReference normalizeDataOrActionPath(final ApiPath apiPath) throws ServerException {
// FIXME: optimize this
final var path = normalizePath(apiPath);
if (path instanceof Data dataPath) {
return dataPath;
}
if (path instanceof Action actionPath) {
return actionPath;
}
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.DATA_MISSING, "Unexpected path %s", path);
}
private NodeIdentifierWithPredicates prepareNodeWithPredicates(final SchemaInferenceStack stack, final QName qname,
final @NonNull ListSchemaNode schema, final List<@NonNull String> keyValues) throws ServerException {
final var keyDef = schema.getKeyDefinition();
final var keySize = keyDef.size();
final var varSize = keyValues.size();
if (keySize != varSize) {
throw new ServerException(ErrorType.PROTOCOL,
keySize > varSize ? ErrorTag.MISSING_ATTRIBUTE : ErrorTag.UNKNOWN_ATTRIBUTE,
"Schema for %s requires %s key values, %s supplied", qname, keySize, varSize);
}
final var values = ImmutableMap.builderWithExpectedSize(keySize);
final var tmp = stack.copy();
for (int i = 0; i < keySize; ++i) {
final QName keyName = keyDef.get(i);
final var child = schema.getDataChildByName(keyName);
tmp.enterSchemaTree(keyName);
values.put(keyName, prepareValueByType(tmp, child, keyValues.get(i)));
tmp.exit();
}
return NodeIdentifierWithPredicates.of(qname, values.build());
}
private Object prepareValueByType(final SchemaInferenceStack stack, final DataSchemaNode schemaNode,
final @NonNull String value) throws ServerException {
if (schemaNode instanceof TypedDataSchemaNode typedSchema) {
return parserJsonValue(stack, typedSchema, value);
}
throw new VerifyException("Unhandled schema " + schemaNode + " decoding '" + value + "'");
}
private Object parserJsonValue(final SchemaInferenceStack stack, final TypedDataSchemaNode schemaNode,
final String value) throws ServerException {
// As per https://www.rfc-editor.org/rfc/rfc8040#page-29:
// The syntax for
// "api-identifier" and "key-value" MUST conform to the JSON identifier
// encoding rules in Section 4 of [RFC7951]: The RESTCONF root resource
// path is required. Additional sub-resource identifiers are optional.
// The characters in a key value string are constrained, and some
// characters need to be percent-encoded, as described in Section 3.5.3.
try {
return databind.jsonCodecs().codecFor(schemaNode, stack).parseValue(value);
} catch (IllegalArgumentException e) {
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.INVALID_VALUE,
"Invalid value '" + value + "' for " + schemaNode.getQName(), e);
}
}
private @NonNull QNameModule resolveNamespace(final String moduleName) throws ServerException {
final var it = databind.modelContext().findModuleStatements(moduleName).iterator();
if (it.hasNext()) {
return it.next().localQNameModule();
}
throw new ServerException(ErrorType.PROTOCOL, ErrorTag.UNKNOWN_ELEMENT,
"Failed to lookup for module with name '%s'.", moduleName);
}
}