Changes to allow exchange rates on a specific day to be stored in Currency Exchange and to be pulled by the necessary transactions based on the posting date.
diff --git a/erpnext/public/js/controllers/transaction.js b/erpnext/public/js/controllers/transaction.js
index 34cbbae..6a0d0f8 100644
--- a/erpnext/public/js/controllers/transaction.js
+++ b/erpnext/public/js/controllers/transaction.js
@@ -424,7 +424,7 @@
 		// Added `ignore_pricing_rule` to determine if document is loading after mapping from another doc
 		if(this.frm.doc.currency && this.frm.doc.currency !== company_currency
 				&& !this.frm.doc.ignore_pricing_rule) {
-			this.get_exchange_rate(this.frm.doc.currency, company_currency,
+			this.get_exchange_rate(this.frm.doc.posting_date, this.frm.doc.currency, company_currency,
 				function(exchange_rate) {
 					me.frm.set_value("conversion_rate", exchange_rate);
 				});
@@ -452,10 +452,11 @@
 		}
 	},
 
-	get_exchange_rate: function(from_currency, to_currency, callback) {
+	get_exchange_rate: function(posting_date, from_currency, to_currency, callback) {
 		return frappe.call({
 			method: "erpnext.setup.utils.get_exchange_rate",
 			args: {
+				posting_date: posting_date,
 				from_currency: from_currency,
 				to_currency: to_currency
 			},
diff --git a/erpnext/setup/doctype/currency_exchange/currency_exchange.json b/erpnext/setup/doctype/currency_exchange/currency_exchange.json
index 1209bc1..4c62e9b 100644
--- a/erpnext/setup/doctype/currency_exchange/currency_exchange.json
+++ b/erpnext/setup/doctype/currency_exchange/currency_exchange.json
@@ -15,13 +15,41 @@
    "allow_on_submit": 0, 
    "bold": 0, 
    "collapsible": 0, 
+   "columns": 0, 
+   "fieldname": "date", 
+   "fieldtype": "Date", 
+   "hidden": 0, 
+   "ignore_user_permissions": 0, 
+   "ignore_xss_filter": 0, 
+   "in_filter": 0, 
+   "in_list_view": 1, 
+   "label": "Date", 
+   "length": 0, 
+   "no_copy": 0, 
+   "permlevel": 0, 
+   "precision": "", 
+   "print_hide": 0, 
+   "print_hide_if_no_value": 0, 
+   "read_only": 0, 
+   "report_hide": 0, 
+   "reqd": 1, 
+   "search_index": 0, 
+   "set_only_once": 0, 
+   "unique": 0, 
+   "width": "5"
+  }, 
+  {
+   "allow_on_submit": 0, 
+   "bold": 0, 
+   "collapsible": 0, 
+   "columns": 0, 
    "fieldname": "from_currency", 
    "fieldtype": "Link", 
    "hidden": 0, 
    "ignore_user_permissions": 0, 
    "ignore_xss_filter": 0, 
    "in_filter": 0, 
-   "in_list_view": 1, 
+   "in_list_view": 0, 
    "label": "From Currency", 
    "length": 0, 
    "no_copy": 0, 
@@ -34,19 +62,21 @@
    "reqd": 1, 
    "search_index": 0, 
    "set_only_once": 0, 
-   "unique": 0
+   "unique": 0, 
+   "width": "3"
   }, 
   {
    "allow_on_submit": 0, 
    "bold": 0, 
    "collapsible": 0, 
+   "columns": 0, 
    "fieldname": "to_currency", 
    "fieldtype": "Link", 
    "hidden": 0, 
    "ignore_user_permissions": 0, 
    "ignore_xss_filter": 0, 
    "in_filter": 0, 
-   "in_list_view": 1, 
+   "in_list_view": 0, 
    "label": "To Currency", 
    "length": 0, 
    "no_copy": 0, 
@@ -59,12 +89,14 @@
    "reqd": 1, 
    "search_index": 0, 
    "set_only_once": 0, 
-   "unique": 0
+   "unique": 0, 
+   "width": "3"
   }, 
   {
    "allow_on_submit": 0, 
    "bold": 0, 
    "collapsible": 0, 
+   "columns": 0, 
    "fieldname": "exchange_rate", 
    "fieldtype": "Float", 
    "hidden": 0, 
@@ -84,7 +116,8 @@
    "reqd": 1, 
    "search_index": 0, 
    "set_only_once": 0, 
-   "unique": 0
+   "unique": 0, 
+   "width": "3"
   }
  ], 
  "hide_heading": 0, 
@@ -98,7 +131,7 @@
  "issingle": 0, 
  "istable": 0, 
  "max_attachments": 0, 
- "modified": "2016-07-25 05:24:26.264021", 
+ "modified": "2016-09-05 22:47:38.746711", 
  "modified_by": "Administrator", 
  "module": "Setup", 
  "name": "Currency Exchange", 
@@ -188,5 +221,8 @@
  "quick_entry": 1, 
  "read_only": 0, 
  "read_only_onload": 0, 
+ "sort_field": "name", 
+ "sort_order": "DESC", 
+ "title_field": "", 
  "track_seen": 0
 }
\ No newline at end of file
diff --git a/erpnext/setup/doctype/currency_exchange/currency_exchange.py b/erpnext/setup/doctype/currency_exchange/currency_exchange.py
index 6022812..7f1a43c 100644
--- a/erpnext/setup/doctype/currency_exchange/currency_exchange.py
+++ b/erpnext/setup/doctype/currency_exchange/currency_exchange.py
@@ -7,13 +7,15 @@
 import frappe
 from frappe import _
 from frappe.model.document import Document
+from frappe.utils import get_datetime, get_datetime_str, formatdate
 
 class CurrencyExchange(Document):
-	def autoname(self):
-		self.name = self.from_currency + "-" + self.to_currency
+    def autoname(self):
+        self.name = formatdate(get_datetime_str(self.date),"yyyy-MM-dd") + "-" + self.from_currency + "-" + self.to_currency
+        #self.name = self.date + "-" + self.from_currency + "-" + self.to_currency
 
-	def validate(self):
-		self.validate_value("exchange_rate", ">", 0)
+    def validate(self):
+        self.validate_value("exchange_rate", ">", 0)
 
-		if self.from_currency == self.to_currency:
-			frappe.throw(_("From Currency and To Currency cannot be same"))
+        if self.from_currency == self.to_currency:
+            frappe.throw(_("From Currency and To Currency cannot be same"))
diff --git a/erpnext/setup/doctype/currency_exchange/test_records.json b/erpnext/setup/doctype/currency_exchange/test_records.json
index 784bf26..4bfcd2e 100644
--- a/erpnext/setup/doctype/currency_exchange/test_records.json
+++ b/erpnext/setup/doctype/currency_exchange/test_records.json
@@ -1,18 +1,21 @@
 [
  {
   "doctype": "Currency Exchange", 
+  "date": "01-01-2016"
   "exchange_rate": 60.0, 
   "from_currency": "USD", 
   "to_currency": "INR"
  }, 
  {
   "doctype": "Currency Exchange", 
+  "date": "01-01-2016"
   "exchange_rate": 0.773, 
   "from_currency": "USD", 
   "to_currency": "EUR"
  }, 
  {
   "doctype": "Currency Exchange", 
+  "date": "01-01-2016"
   "exchange_rate": 0.0167, 
   "from_currency": "INR", 
   "to_currency": "USD"
diff --git a/erpnext/setup/utils.py b/erpnext/setup/utils.py
index eda2042..c340cac 100644
--- a/erpnext/setup/utils.py
+++ b/erpnext/setup/utils.py
@@ -5,95 +5,95 @@
 import frappe
 from frappe import _, throw
 from frappe.utils import flt
+from frappe.utils import get_datetime, get_datetime_str
 
 def get_company_currency(company):
-	currency = frappe.db.get_value("Company", company, "default_currency", cache=True)
-	if not currency:
-		currency = frappe.db.get_default("currency")
-	if not currency:
-		throw(_('Please specify Default Currency in Company Master and Global Defaults'))
+    currency = frappe.db.get_value("Company", company, "default_currency", cache=True)
+    if not currency:
+        currency = frappe.db.get_default("currency")
+    if not currency:
+        throw(_('Please specify Default Currency in Company Master and Global Defaults'))
 
-	return currency
+    return currency
 
 def get_root_of(doctype):
-	"""Get root element of a DocType with a tree structure"""
-	result = frappe.db.sql_list("""select name from `tab%s`
-		where lft=1 and rgt=(select max(rgt) from `tab%s` where docstatus < 2)""" %
-		(doctype, doctype))
-	return result[0] if result else None
+    """Get root element of a DocType with a tree structure"""
+    result = frappe.db.sql_list("""select name from `tab%s`
+        where lft=1 and rgt=(select max(rgt) from `tab%s` where docstatus < 2)""" %
+        (doctype, doctype))
+    return result[0] if result else None
 
 def get_ancestors_of(doctype, name):
-	"""Get ancestor elements of a DocType with a tree structure"""
-	lft, rgt = frappe.db.get_value(doctype, name, ["lft", "rgt"])
-	result = frappe.db.sql_list("""select name from `tab%s`
-		where lft<%s and rgt>%s order by lft desc""" % (doctype, "%s", "%s"), (lft, rgt))
-	return result or []
+    """Get ancestor elements of a DocType with a tree structure"""
+    lft, rgt = frappe.db.get_value(doctype, name, ["lft", "rgt"])
+    result = frappe.db.sql_list("""select name from `tab%s`
+        where lft<%s and rgt>%s order by lft desc""" % (doctype, "%s", "%s"), (lft, rgt))
+    return result or []
 
 def before_tests():
-	frappe.clear_cache()
-	# complete setup if missing
-	from frappe.desk.page.setup_wizard.setup_wizard import setup_complete
-	if not frappe.get_list("Company"):
-		setup_complete({
-			"currency"			:"USD",
-			"first_name"		:"Test",
-			"last_name"			:"User",
-			"company_name"		:"Wind Power LLC",
-			"timezone"			:"America/New_York",
-			"company_abbr"		:"WP",
-			"industry"			:"Manufacturing",
-			"country"			:"United States",
-			"fy_start_date"		:"2011-01-01",
-			"fy_end_date"		:"2011-12-31",
-			"language"			:"english",
-			"company_tagline"	:"Testing",
-			"email"				:"test@erpnext.com",
-			"password"			:"test",
-			"chart_of_accounts" : "Standard",
-			"domain"			: "Manufacturing",
-			
-		})
+    frappe.clear_cache()
+    # complete setup if missing
+    from frappe.desk.page.setup_wizard.setup_wizard import setup_complete
+    if not frappe.get_list("Company"):
+        setup_complete({
+            "currency"            :"USD",
+            "first_name"        :"Test",
+            "last_name"            :"User",
+            "company_name"        :"Wind Power LLC",
+            "timezone"            :"America/New_York",
+            "company_abbr"        :"WP",
+            "industry"            :"Manufacturing",
+            "country"            :"United States",
+            "fy_start_date"        :"2011-01-01",
+            "fy_end_date"        :"2011-12-31",
+            "language"            :"english",
+            "company_tagline"    :"Testing",
+            "email"                :"test@erpnext.com",
+            "password"            :"test",
+            "chart_of_accounts" : "Standard",
+            "domain"            : "Manufacturing",
+            
+        })
 
-	frappe.db.sql("delete from `tabLeave Allocation`")
-	frappe.db.sql("delete from `tabLeave Application`")
-	frappe.db.sql("delete from `tabSalary Slip`")
-	frappe.db.sql("delete from `tabItem Price`")
+    frappe.db.sql("delete from `tabLeave Allocation`")
+    frappe.db.sql("delete from `tabLeave Application`")
+    frappe.db.sql("delete from `tabSalary Slip`")
+    frappe.db.sql("delete from `tabItem Price`")
 
-	frappe.db.set_value("Stock Settings", None, "auto_insert_price_list_rate_if_missing", 0)
+    frappe.db.set_value("Stock Settings", None, "auto_insert_price_list_rate_if_missing", 0)
 
-	frappe.db.commit()
+    frappe.db.commit()
 
 @frappe.whitelist()
-def get_exchange_rate(from_currency, to_currency):
-	if not (from_currency and to_currency):
-		return
-	
-	if from_currency == to_currency:
-		return 1
-	
-	exchange = "%s-%s" % (from_currency, to_currency)
-	value = flt(frappe.db.get_value("Currency Exchange", exchange, "exchange_rate"))
+def get_exchange_rate(posting_date, from_currency, to_currency):
+    if not (posting_date and from_currency and to_currency):
+        return
+    
+    if from_currency == to_currency:
+        return 1
+    
+    #Get all entries in Currency Exchange with from_currency and to_currency
+    entries = frappe.get_all("Currency Exchange", fields = ["*"], filters=[["date", "<=", get_datetime_str(posting_date)], ["from_currency", "=", from_currency], ["to_currency", "=", to_currency]], order_by="date desc")
+    if entries:
+        return flt(entries[0].exchange_rate)
 
-	if not value:
-		try:
-			cache = frappe.cache()
-			key = "currency_exchange_rate:{0}:{1}".format(from_currency, to_currency)
-			value = cache.get(key)
+    try:
+        cache = frappe.cache()
+        key = "currency_exchange_rate:{0}:{1}".format(from_currency, to_currency)
+        value = cache.get(key)
 
-			if not value:
-				import requests
-				response = requests.get("http://api.fixer.io/latest", params={
-					"base": from_currency,
-					"symbols": to_currency
-				})
-				# expire in 6 hours
-				response.raise_for_status()
-				value = response.json()["rates"][to_currency]
-				cache.setex(key, value, 6 * 60 * 60)
+        if not value:
+            import requests
+            response = requests.get("http://api.fixer.io/latest", params={
+                "base": from_currency,
+                "symbols": to_currency
+            })
+            # expire in 6 hours
+            response.raise_for_status()
+            value = response.json()["rates"][to_currency]
+            cache.setex(key, value, 6 * 60 * 60)
 
-			return flt(value)
-		except:
-			frappe.msgprint(_("Unable to find exchange rate for {0} to {1}").format(from_currency, to_currency))
-			return 0.0
-	else:
-		return value
+        return flt(value)
+    except:
+        frappe.msgprint(_("Unable to find exchange rate for {0} to {1} for key date {2}").format(from_currency, to_currency, posting_date))
+        return 0.0
\ No newline at end of file