Introduce schema for compose's configuration file.

compose/config.py

@@ -1,6 +1,9 @@
+import json
+import jsonschema
 import os
 import yaml
 import six
+import sys
 
 
 DOCKER_CONFIG_KEYS = [
@@ -51,9 +54,25 @@
 }
 
 
+def validate_schema(config_data):
+    config_source_dir = os.path.dirname(os.path.abspath(__file__))
+    schema_file = os.path.join(config_source_dir, "schema.json")
+
+    with open(schema_file) as schema_fh:
+        schema = json.load(schema_fh)
+
+    try:
+        jsonschema.validate(config_data, schema)
+    except jsonschema.exceptions.ValidationError as e:
+        exctype, value = sys.exc_info()[:2]
+        raise Exception("Validation failed, reason: (%s)" % e.message)
+
+
 def load(filename):
     working_dir = os.path.dirname(filename)
-    return from_dictionary(load_yaml(filename), working_dir=working_dir, filename=filename)
+    config_data = load_yaml(filename)
+    validate_schema(config_data)
+    return from_dictionary(config_data, working_dir=working_dir, filename=filename)
 
 
 def from_dictionary(dictionary, working_dir=None, filename=None):

compose/empty_schema.json

@@ -0,0 +1 @@
+{}

compose/schema.json

@@ -0,0 +1,137 @@
+{
+    "$schema": "http://json-schema.org/draft-04/schema#",
+
+    "type": "object",
+
+    "patternProperties": {
+        "^[a-zA-Z0-9]+$": {
+            "$ref": "#/definitions/service"
+        }
+    },    
+
+    "additionalProperties": false,
+
+    "definitions": {
+        "service": {
+            "type": "object",
+            "properties": {
+                "build": { "type": "string" },
+
+                "image": { "type": "string" },
+
+                "command": { "$ref": "#/definitions/string_or_stringlist" },
+
+                "links": {
+                    "$ref": "#/definitions/stringlist"
+                },
+
+                "external_links": {
+                    "$ref": "#/definitions/stringlist"
+                },
+
+                "expose": {
+                    "$ref": "#/definitions/stringlist"
+                },
+
+                "volumes": {
+                    "$ref": "#/definitions/stringlist"
+                },
+
+                "volumes_from": {
+                    "$ref": "#/definitions/stringlist"
+                },
+
+                "net": {
+                    "type": "string"
+                },
+
+                "cap_add": {
+                    "$ref": "#/definitions/stringlist"
+                },
+
+                "drop": {
+                    "$ref": "#/definitions/stringlist"
+                },
+
+                "working_dir": { "type": "string" },
+
+                "entrypoint": { "type": "string" },
+
+                "user": { "type": "string" },
+
+                "hostname": { "type": "string" },
+
+                "domainname": { "type": "string" },
+
+                "mem_limit": { "type": "string" },
+
+                "privileged": { "type": "string" },
+
+                "restart": { "type": "string" },
+
+                "stdin_open": { "type": "string" },
+
+                "tty": { "type": "string" },
+
+                "cpu_shares": { "type": "string" },
+
+                "build": { "type": "string" },
+
+                "image": { "type": "string" },
+
+                "ports": {
+                    "$ref": "#/definitions/stringlist"
+                },
+
+                "environment": {
+                    "$ref": "#/definitions/dict_or_list"
+                },
+
+                "env_file": { "$ref": "#/definitions/string_or_stringlist" },
+
+                "dns": { "$ref": "#/definitions/string_or_stringlist" },
+
+                "dns_search": { "$ref": "#/definitions/string_or_stringlist" },
+
+                "extends": {
+                    "type": "object",
+                    "properties": {
+                        "file": { "type": "string" },
+                        "service": { "type": "string" }
+                    },
+                    "required": [ "file", "service" ]
+                }
+            },
+
+            "additionalProperties": false
+        },
+
+        "string_or_stringlist": {
+            "oneOf": [
+                { "type": "string" },
+                {
+                    "type": "array",
+                    "items": {"type": "string"},
+                    "uniqueItems": true
+                }
+            ]
+        },
+
+        "stringlist": {
+            "type": "array",
+            "items": {"type": "string"},
+            "uniqueItems": true
+        },
+
+        "dict_or_list": {
+            "oneOf": [
+                { "type": "object" },
+                {
+                    "type": "array",
+                    "items": {"type": "string"},
+                    "uniqueItems": true
+                }
+            ]
+        }
+    }
+}

compose/testconfig/issue117_118.yml

@@ -0,0 +1,16 @@
+mongodb:
+  image: dockerfile/mongodb
+  ports:
+    - 27017:27017
+    - 27018:27018
+  volumes: /data/db:/data/db 
+
+web:
+  image: foo:dev
+  links:
+    - mongodb
+  ports:
+    - 3000:3000
+  volumes:
+    - ../../:/home/foo/
+  command: bin/webapp

compose/testconfig/issue127.yml

@@ -0,0 +1,11 @@
+image: stackbrew/ubuntu
+ports:
+  - 3306:3306
+  - 6379:6379
+links:
+   - mysql
+   - redis
+mysql:
+  image: orchardup/mysql
+redis:
+  image: orchardup/redis

compose/testconfig/top_level_not_dict.yml

@@ -0,0 +1,2 @@
+- mysql
+- redis

requirements.txt

@@ -6,3 +6,4 @@ requests==2.2.1
 six==1.7.3
 texttable==0.8.2
 websocket-client==0.11.0
+jsonschema==2.4.0