Support for policy query (#143)

docs/authorization_spec.md

@@ -16,7 +16,7 @@
 Create a new object policy that describes an access logic that can be attached to a graphql field.
 Some examples:
 
-### Policy that always allows access:
+### Policy that always allows access
 
 ```yaml
 kind: Policy
@@ -28,7 +28,7 @@ Spec:
     code: {'result': 'allow'}
 ```
 
-### Policy that allows access only if the issuer is "abc.com":
+### Policy that allows access only if the issuer is "abc.com"
 
 ```yaml
 kind: Policy
@@ -62,7 +62,7 @@ Spec:
 
 _Note the js-expression type is an example of a possible type and not planned to be implemented at this time._
 
-### Policy that uses a graphql query to fetch additional data and allows based on the results and an argument:
+### Policy that uses a graphql query to fetch additional data and allows based on the results and an argument
 
 ```yaml
 kind: Policy
@@ -74,29 +74,29 @@ Spec:
     code: |
         allow = false
         allow = {
-          input.args.userId == input.queries.familyQuery.family.members[_].id
+          input.args.userId == input.query.user.family.members[_].id
         }
     args:
         userId: ID!
-    queries:
-        - type: graphql
-          name: familyQuery
-          graphql:
-              query: |
-                  {
-                    user({jwt.sub}) {
-                      family {
-                        members {
-                          id
-                        }
-                      }
-                    }
+        sub: ID!
+    query:
+        gql: |
+            query ($sub: String!) {
+              user(sub: $sub) {
+                family {
+                  members {
+                    id
                   }
+                }
+              }
+            }
+        variables:
+            sub: '{args.sub}'
 ```
 
 Queries support the standard Stitch parameter injection syntax, but only support the `jwt` and `args` objects for injection
 
-### Same as the previous policy, but evaluates the query while opa is running:
+### Same as the previous policy, but evaluates the query while opa is running
 
 ```yaml
 kind: Policy
@@ -118,7 +118,7 @@ Spec:
 
 This example will always evaluate the graphql query, but generally this approach should be used when conditional side effect evaluation is needed
 
-### Policy that uses a policy query and allows based on the results:
+### Policy that uses another policy as query and allows based on the results
 
 ```yaml
 kind: Policy
@@ -130,24 +130,26 @@ Spec:
     code: |
         allow = false
         allow = {
-          input.queries.myUserPolicy == true
+          input.query.myUserPolicy == true
         }
     args:
         userId: ID!
-    queries:
-        - type: policy
-          name: myUserPolicy
-          policy:
-              policyName: my-user
-              args:
-                  userId: '{args.userId}'
+    query:
+        gql: |
+          query(userId: ID!) {
+            policy.my_user(userId: $userId) {
+              allow
+            }
+          }
+      variables:
+        userId: '{args.userId}'
 ```
 
 `args` for query policy can use parameter injection from the `jwt` and `args` objects, similarly to the graphql query
 
 ### Attach policy to fields:
 
-```
+```gql
 type User {
   ID: ID!
   Picture: String @policy-some-ns-public
@@ -163,7 +165,7 @@ Adding args support to policies can ease memoization and remove hidden dependenc
 
 Initially, we will support a single `@policy` directive that gets an array of policy names and their args:
 
-```
+```gql
 type User {
   Picture: String @policy(policies: [
     { namespace: "some-ns", name: “my-user”, args: { userId: “{source.UserId}” } },
@@ -179,13 +181,13 @@ Later on, for convenience and type safety, we will add an alternative syntax or
 1. Client requests a graphql query that includes a field that has a `@policy` directive.
 2. Server activates the policy resolver and reads the arguments with parameter injection.
 3. The resolver passes the args to a policy executor.
-   The policy executor invokes the right binding (see policy implementation contract) and manages the queries for the policy.
+   The policy executor invokes the right binding (see policy implementation contract) and manages the query for the policy.
 4. The policy executor should return true/false if the user has access or a string describing the failure.
 5. If the user has access, return the field value. Otherwise, return an error.
 
 ## Policy implementation contract
 
-The naive js contract can be implemented with a generator, that has a result of true/false and can yield queries.
+The naive js contract can be implemented with a generator, that has a result of true/false and can yield query.
 All queries and policy evaluation itself are memoized for a request context for same query/policy arguments.
 
 ```typescript
@@ -280,7 +282,7 @@ Spec:
 
 Usage:
 
-```
+```gql
 type User {
   ID: ID!
   Picture: String @policy-some-ns-has-claims(claims:["issuer", "sub"], values: ["soluto.com", "{source.UserId}"], jwtClaims: "{jwt.claims}")

services/package.json

@@ -15,6 +15,7 @@
     "dependencies": {
         "@apollo/federation": "^0.12.1",
         "@open-policy-agent/opa-wasm": "^1.1.0",
+        "@types/ramda": "^0.27.6",
         "apollo-datasource-rest": "^0.7.0",
         "apollo-link-context": "^1.0.19",
         "apollo-link-http": "^1.5.16",
@@ -36,6 +37,7 @@
         "p-limit": "^2.2.2",
         "pino": "^5.16.0",
         "pino-pretty": "^3.6.1",
+        "ramda": "^0.27.0",
         "rxjs": "^6.5.4",
         "tslib": "^1.11.0"
     },

services/src/modules/baseSchema.ts

@@ -3,6 +3,7 @@ import GraphQLJSON, {GraphQLJSONObject} from 'graphql-type-json';
 import {GraphQLDate, GraphQLDateTime, GraphQLTime} from 'graphql-iso-date';
 import {concatAST} from 'graphql';
 import {sdl as directivesSdl} from './directives';
+import {GraphQLResolverMap} from 'apollo-graphql';
 
 export const baseTypeDef = gql`
     scalar JSON
@@ -11,11 +12,19 @@ export const baseTypeDef = gql`
     scalar Date
     scalar Time
     scalar DateTime
+
+    type PolicyResult {
+        allow: Boolean!
+    }
+
+    type Policy {
+        default: PolicyResult!
+    }
 `;
 
 export const typeDef = concatAST([baseTypeDef, directivesSdl]);
 
-export const resolvers = {
+export const resolvers: GraphQLResolverMap<{}> = {
     JSON: GraphQLJSON,
     JSONObject: GraphQLJSONObject,
     Date: GraphQLDate,

services/src/modules/directives/index.ts

@@ -6,6 +6,7 @@ import {sdl as gqlSdl, GqlDirective} from './gql';
 import {sdl as exportSdl, ExportDirective} from './export';
 import {sdl as selectSdl, SelectDirective} from './select';
 import {sdl as policySdl, PolicyDirective} from './policy/policy';
+import {sdl as policyQuerySdl, PolicyQueryDirective} from './policy/policy-query';
 
 export const directiveMap: {[visitorName: string]: typeof SchemaDirectiveVisitor} = {
     stub: StubDirective,
@@ -14,6 +15,7 @@ export const directiveMap: {[visitorName: string]: typeof SchemaDirectiveVisitor
     export: ExportDirective,
     select: SelectDirective,
     policy: PolicyDirective,
+    policyQuery: PolicyQueryDirective,
 };
 
-export const sdl = concatAST([stubSdl, restSdl, gqlSdl, exportSdl, selectSdl, policySdl]);
+export const sdl = concatAST([stubSdl, restSdl, gqlSdl, exportSdl, selectSdl, policySdl, policyQuerySdl]);

services/src/modules/directives/policy/opa.ts

@@ -1,7 +1,7 @@
 // @ts-ignore opa-wasm already has TS typings merged, but not yet published on npm
 import * as Rego from '@open-policy-agent/opa-wasm';
 import {getCompiledFilename} from '../../opaHelper';
-import {PolicyExecutionContext, PolicyExecutionResult, QueriesResults} from './types';
+import {PolicyExecutionContext, PolicyExecutionResult, QueryResults} from './types';
 import {PolicyArgsObject} from '../../resource-repository';
 
 export async function evaluate(ctx: PolicyExecutionContext): Promise<PolicyExecutionResult> {
@@ -21,16 +21,16 @@ async function getWasmPolicy(ctx: PolicyExecutionContext): Promise<any> {
     return rego.load_policy(wasm);
 }
 
-function getInput(ctx: PolicyExecutionContext): PolicyInput {
-    const input: PolicyInput = {};
+function getInput(ctx: PolicyExecutionContext): PolicyOpaInput {
+    const input: PolicyOpaInput = {};
 
     if (ctx.args) input.args = ctx.args;
-    if (ctx.queries) input.queries = ctx.queries;
+    if (ctx.query) input.query = ctx.query;
 
     return input;
 }
 
-type PolicyInput = {
+type PolicyOpaInput = {
     args?: PolicyArgsObject;
-    queries?: QueriesResults;
+    query?: QueryResults;
 };