Implement header (and footer) support

index.js

@@ -15,7 +15,7 @@ var Parser = require('jsonparse')
 */
 
 exports.parse = function (path, map) {
-
+  var header, footer
   var parser = new Parser()
   var stream = through(function (chunk) {
     if('string' === typeof chunk)
@@ -25,6 +25,10 @@ exports.parse = function (path, map) {
   function (data) {
     if(data)
       stream.write(data)
+    if (header)
+        stream.emit('header', header)
+    if (footer)
+      stream.emit('footer', footer)
     stream.queue(null)
   })
 
@@ -62,7 +66,10 @@ exports.parse = function (path, map) {
       if (key && !key.recurse) {
         c = (j === this.stack.length) ? this : this.stack[j]
         if (!c) return
-        if (! check(key, c.key)) return
+        if (! check(key, c.key)) {
+          setHeaderFooter(c.key, value)
+          return
+        }
         emitKey = !!key.emitKey;
         i++
       } else {
@@ -77,6 +84,8 @@ exports.parse = function (path, map) {
             if (!Object.isFrozen(this.stack[j]))
               this.stack[j].value = null
             break
+          } else {
+            setHeaderFooter(c.key, value)
           }
           j++
         }
@@ -97,6 +106,12 @@ exports.parse = function (path, map) {
     for(var k in this.stack)
       if (!Object.isFrozen(this.stack[k]))
         this.stack[k].value = null
+
+    // emit header
+    if (header) {
+      stream.emit('header', header);
+      header = false;
+    }
   }
   parser._onToken = parser.onToken;
 
@@ -118,8 +133,21 @@ exports.parse = function (path, map) {
     stream.emit('error', err)
   }
 
-
   return stream
+
+  function setHeaderFooter(key, value) {
+    // header has not been emitted yet
+    if (header !== false) {
+      header = header || {}
+      header[key] = value
+    }
+
+    // footer has not been emitted yet but header has
+    if (footer !== false && header === false) {
+      footer = footer || {}
+      footer[key] = value
+    }
+  }
 }
 
 function check (x, y) {

test/error_contents.js

@@ -0,0 +1,45 @@
+
+
+var fs = require ('fs')
+  , join = require('path').join
+  , file = join(__dirname, 'fixtures','error.json')
+  , JSONStream = require('../')
+  , it = require('it-is')
+
+var expected = JSON.parse(fs.readFileSync(file))
+  , parser = JSONStream.parse(['rows'])
+  , called = 0
+  , headerCalled = 0
+  , footerCalled = 0
+  , ended = false
+  , parsed = []
+
+fs.createReadStream(file).pipe(parser)
+
+parser.on('header', function (data) {
+  headerCalled ++
+  it(data).deepEqual({
+    error: 'error_code',
+    message: 'this is an error message'
+  })
+})
+
+parser.on('footer', function (data) {
+  footerCalled ++
+})
+
+parser.on('data', function (data) {
+  called ++
+  parsed.push(data)
+})
+
+parser.on('end', function () {
+  ended = true
+})
+
+process.on('exit', function () {
+  it(called).equal(0)
+  it(headerCalled).equal(1)
+  it(footerCalled).equal(0)
+  console.error('PASSED')
+})

test/fixtures/error.json

@@ -0,0 +1 @@
+{"error": "error_code", "message": "this is an error message"}

test/fixtures/header_footer.json

@@ -0,0 +1,19 @@
+{"total_rows":129,"offset":0,"rows":[
+  { "id":"change1_0.6995461115147918"
+  , "key":"change1_0.6995461115147918"
+  , "value":{"rev":"1-e240bae28c7bb3667f02760f6398d508"}
+  , "doc":{
+      "_id":  "change1_0.6995461115147918"
+    , "_rev": "1-e240bae28c7bb3667f02760f6398d508","hello":1}
+  },
+  { "id":"change2_0.6995461115147918"
+  , "key":"change2_0.6995461115147918"
+  , "value":{"rev":"1-13677d36b98c0c075145bb8975105153"}
+  , "doc":{
+      "_id":"change2_0.6995461115147918"
+    , "_rev":"1-13677d36b98c0c075145bb8975105153"
+    , "hello":2
+    }
+  }
+],
+"foo": {"bar": "baz"}}

test/header_footer.js

@@ -0,0 +1,54 @@
+
+
+var fs = require ('fs')
+  , join = require('path').join
+  , file = join(__dirname, 'fixtures','header_footer.json')
+  , JSONStream = require('../')
+  , it = require('it-is')
+
+var expected = JSON.parse(fs.readFileSync(file))
+  , parser = JSONStream.parse(['rows', /\d+/ /*, 'value'*/])
+  , called = 0
+  , headerCalled = 0
+  , footerCalled = 0
+  , ended = false
+  , parsed = []
+
+fs.createReadStream(file).pipe(parser)
+
+parser.on('header', function (data) {
+  headerCalled ++
+  it(data).deepEqual({
+    total_rows: 129,
+    offset: 0
+  })
+})
+
+parser.on('footer', function (data) {
+  footerCalled ++
+  it(data).deepEqual({
+    foo: { bar: 'baz' }
+  })
+})
+
+parser.on('data', function (data) {
+  called ++
+  it.has({
+    id: it.typeof('string'),
+    value: {rev: it.typeof('string')},
+    key:it.typeof('string')
+  })
+  parsed.push(data)
+})
+
+parser.on('end', function () {
+  ended = true
+})
+
+process.on('exit', function () {
+  it(called).equal(expected.rows.length)
+  it(headerCalled).equal(1)
+  it(footerCalled).equal(1)
+  it(parsed).deepEqual(expected.rows)
+  console.error('PASSED')
+})