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-rw-r--r--sca-cpp/trunk/components/sqldb/client-test.cpp26
-rwxr-xr-xsca-cpp/trunk/components/sqldb/pgsql-conf6
-rwxr-xr-xsca-cpp/trunk/components/sqldb/pgsql-standby-conf7
-rw-r--r--sca-cpp/trunk/components/sqldb/pgsql-standby-test.cpp3
-rw-r--r--sca-cpp/trunk/components/sqldb/pgsql-test.cpp2
-rw-r--r--sca-cpp/trunk/components/sqldb/pgsql.hpp207
-rw-r--r--sca-cpp/trunk/components/sqldb/sqldb.cpp61
7 files changed, 277 insertions, 35 deletions
diff --git a/sca-cpp/trunk/components/sqldb/client-test.cpp b/sca-cpp/trunk/components/sqldb/client-test.cpp
index c9fbb7d5bb..fcdb8d3c2a 100644
--- a/sca-cpp/trunk/components/sqldb/client-test.cpp
+++ b/sca-cpp/trunk/components/sqldb/client-test.cpp
@@ -77,6 +77,32 @@ const bool testSqlDb() {
assert(hasContent(val));
assert(content(val) == b);
}
+
+ const list<value> k = nilListValue + "content" + (nilListValue + "item"
+ + (nilListValue + "name" + string("Apple"))
+ + (nilListValue + "price" + string("$3.99")));
+ const list<value> c = nilListValue + (nilListValue + "entry"
+ + (nilListValue + "title" + string("item"))
+ + (nilListValue + "id" + string("cart-53d67a61-aa5e-4e5e-8401-39edeba8b83b"))
+ + k);
+
+ {
+ const list<value> s = nilListValue + "content" +
+ (nilListValue + "patch" + string("(define (patch id e) (tree-subst-assoc '(price) '(price \"$3.99\") e))"));
+ const list<value> ps = nilListValue + (nilListValue + "entry"
+ + (nilListValue + "title" + string("item"))
+ + (nilListValue + "id" + string("cart-53d67a61-aa5e-4e5e-8401-39edeba8b83b"))
+ + s);
+
+ const failable<value> r = http::patch(ps, uri + p, cs);
+ assert(hasContent(r));
+ assert(content(r) == trueValue);
+ }
+ {
+ const failable<value> val = http::get(uri + p, cs);
+ assert(hasContent(val));
+ assert(content(val) == c);
+ }
{
const failable<value> r = http::del(uri + p, cs);
assert(hasContent(r));
diff --git a/sca-cpp/trunk/components/sqldb/pgsql-conf b/sca-cpp/trunk/components/sqldb/pgsql-conf
index 8adbb902c9..020ce129fb 100755
--- a/sca-cpp/trunk/components/sqldb/pgsql-conf
+++ b/sca-cpp/trunk/components/sqldb/pgsql-conf
@@ -96,6 +96,7 @@ archive_command = '$here/pgsql-archive $root $host $bport %p %f'
wal_level = hot_standby
max_wal_senders = 5
wal_keep_segments = 32
+#synchronous_standby_names = '*'
EOF
@@ -166,7 +167,6 @@ cat >$root/sqldb/data/pgbouncer.conf <<EOF
db = host=$host port=$port dbname=db user=bouncer
[pgbouncer]
-pool_mode = session
listen_addr = $listen
listen_port = $bport
unix_socket_dir =
@@ -177,9 +177,9 @@ pidfile = $root/logs/pgbouncer.pid
max_client_conn = 1000
pool_mode = transaction
server_reset_query =
-default_pool_size = 500
+default_pool_size = 50
min_pool_size = 5
-reserve_pool_size = 50
+reserve_pool_size = 5
log_connections = 0
log_disconnections = 0
stats_period = 3600
diff --git a/sca-cpp/trunk/components/sqldb/pgsql-standby-conf b/sca-cpp/trunk/components/sqldb/pgsql-standby-conf
index 5f76b5b332..ae2ed8e909 100755
--- a/sca-cpp/trunk/components/sqldb/pgsql-standby-conf
+++ b/sca-cpp/trunk/components/sqldb/pgsql-standby-conf
@@ -126,7 +126,7 @@ cat >$root/sqldb/data/recovery.conf << EOF
# Start in standby mode
standby_mode = 'on'
-primary_conninfo = 'host=$mhost port=$mport user=standby'
+primary_conninfo = 'host=$mhost port=$mport user=standby application_name=$host:$port'
# Failover
trigger_file = '$root/sqldb/failover'
@@ -165,7 +165,6 @@ cat >$root/sqldb/data/pgbouncer.conf <<EOF
db = host=$host port=$port dbname=db user=bouncer
[pgbouncer]
-pool_mode = session
listen_addr = $listen
listen_port = $bport
unix_socket_dir =
@@ -176,9 +175,9 @@ pidfile = $root/logs/pgbouncer.pid
max_client_conn = 1000
pool_mode = transaction
server_reset_query =
-default_pool_size = 500
+default_pool_size = 50
min_pool_size = 5
-reserve_pool_size = 50
+reserve_pool_size = 5
log_connections = 0
log_disconnections = 0
stats_period = 3600
diff --git a/sca-cpp/trunk/components/sqldb/pgsql-standby-test.cpp b/sca-cpp/trunk/components/sqldb/pgsql-standby-test.cpp
index 5d73b0d877..319194ab41 100644
--- a/sca-cpp/trunk/components/sqldb/pgsql-standby-test.cpp
+++ b/sca-cpp/trunk/components/sqldb/pgsql-standby-test.cpp
@@ -43,6 +43,9 @@ const bool testPGSql() {
assert(hasContent(put(k, string("aaa"), wpg)));
sleep(1);
assert((get(k, rpg)) == value(string("aaa")));
+ assert(hasContent(patch(k, string("bbb"), wpg)));
+ sleep(1);
+ assert((get(k, rpg)) == value(string("bbb")));
assert(hasContent(del(k, wpg)));
sleep(1);
assert(!hasContent(get(k, rpg)));
diff --git a/sca-cpp/trunk/components/sqldb/pgsql-test.cpp b/sca-cpp/trunk/components/sqldb/pgsql-test.cpp
index 5d7bb98cd8..ec5d537b44 100644
--- a/sca-cpp/trunk/components/sqldb/pgsql-test.cpp
+++ b/sca-cpp/trunk/components/sqldb/pgsql-test.cpp
@@ -49,6 +49,8 @@ const bool testPGSql() {
assert(hasContent(put(k, string("aaa"), pg)));
assert(content(get(k, pg)) == value(string("aaa")));
+ assert(hasContent(patch(k, string("bbb"), pg)));
+ assert(content(get(k, pg)) == value(string("bbb")));
assert(hasContent(del(k, pg)));
assert(!hasContent(get(k, pg)));
diff --git a/sca-cpp/trunk/components/sqldb/pgsql.hpp b/sca-cpp/trunk/components/sqldb/pgsql.hpp
index 620aec4105..5e0004c4e6 100644
--- a/sca-cpp/trunk/components/sqldb/pgsql.hpp
+++ b/sca-cpp/trunk/components/sqldb/pgsql.hpp
@@ -75,12 +75,15 @@ public:
string ks = string("select a.attname from pg_attribute a, pg_class c where a.attrelid = c.relfilenode and c.relname = '") + table + string("' and a.attnum in (1, 2) order by a.attnum;");
PGresult* const kr = PQexec(conn, c_str(ks));
if (PQresultStatus(kr) != PGRES_TUPLES_OK) {
- mkfailure<bool>(string("Couldn't execute postgresql column select statement: ") + pgfailure(kr, conn));
+ const string rs = string("Couldn't execute postgresql column select statement: ") + pgfailure(kr, conn);
+ PQclear(kr);
+ mkfailure<bool>(rs);
return;
}
if (PQntuples(kr) != 2) {
+ const string rs = "Couldn't find postgresql table key and value column names";
PQclear(kr);
- mkfailure<bool>(string("Couldn't find postgresql table key and value column names"));
+ mkfailure<bool>(rs);
return;
}
kname = c_str(string(PQgetvalue(kr, 0, 0)));
@@ -95,12 +98,10 @@ public:
PGSql& operator=(const PGSql& c) = delete;
~PGSql() {
- debug("pgsql::~pgsql");
if (!owner)
return;
if (conn == NULL)
return;
- debug(conn, "pgsql::~pgsql::conn");
PQfinish(conn);
}
@@ -113,8 +114,12 @@ private:
const char* vname;
friend const failable<bool> setup(const PGSql& pgsql);
+ friend const failable<bool> begin(const PGSql& pgsql);
+ friend const failable<bool> commit(const PGSql& pgsql);
+ friend const failable<bool> rollback(const PGSql& pgsql);
friend const failable<bool> post(const value& key, const value& val, const PGSql& pgsql);
friend const failable<bool> put(const value& key, const value& val, const PGSql& pgsql);
+ friend const failable<bool> patch(const value& key, const value& val, const PGSql& pgsql);
friend const failable<value> get(const value& key, const PGSql& pgsql);
friend const failable<bool> del(const value& key, const PGSql& pgsql);
};
@@ -134,6 +139,69 @@ const failable<bool> setup(const PGSql& pgsql) {
}
/**
+ * Begin a database transaction.
+ */
+const failable<bool> begin(const PGSql& pgsql) {
+ debug("pgsql::begin");
+ debug(pgsql.conninfo, "pgsql::begin::conninfo");
+ debug(pgsql.table, "pgsql::begin::table");
+ setup(pgsql);
+
+ PGresult* const r = PQexec(pgsql.conn, "begin transaction isolation level repeatable read");
+ if (PQresultStatus(r) != PGRES_COMMAND_OK) {
+ const string rs = string("Couldn't execute begin SQL statement: ") + pgfailure(r, pgsql.conn);
+ PQclear(r);
+ return mkfailure<bool>(rs);
+ }
+ PQclear(r);
+
+ debug(true, "pgsql::begin::result");
+ return true;
+}
+
+/**
+ * Commit a database transaction.
+ */
+const failable<bool> commit(const PGSql& pgsql) {
+ debug("pgsql::commit");
+ debug(pgsql.conninfo, "pgsql::commit::conninfo");
+ debug(pgsql.table, "pgsql::commit::table");
+ setup(pgsql);
+
+ PGresult* const r = PQexec(pgsql.conn, "commit");
+ if (PQresultStatus(r) != PGRES_COMMAND_OK) {
+ const string rs = string("Couldn't execute commit SQL statement: ") + pgfailure(r, pgsql.conn);
+ PQclear(r);
+ return mkfailure<bool>(rs);
+ }
+ PQclear(r);
+
+ debug(true, "pgsql::commit::result");
+ return true;
+}
+
+/**
+ * Rollback a database transaction.
+ */
+const failable<bool> rollback(const PGSql& pgsql) {
+ debug("pgsql::rollback");
+ debug(pgsql.conninfo, "pgsql::rollback::conninfo");
+ debug(pgsql.table, "pgsql::rollback::table");
+ setup(pgsql);
+
+ PGresult* const r = PQexec(pgsql.conn, "rollback");
+ if (PQresultStatus(r) != PGRES_COMMAND_OK) {
+ const string rs = string("Couldn't execute rollback SQL statement: ") + pgfailure(r, pgsql.conn);
+ PQclear(r);
+ return mkfailure<bool>(rs);
+ }
+ PQclear(r);
+
+ debug(true, "pgsql::rollback::result");
+ return true;
+}
+
+/**
* Post a new item to the database.
*/
const failable<bool> post(const value& key, const value& val, const PGSql& pgsql) {
@@ -147,8 +215,11 @@ const failable<bool> post(const value& key, const value& val, const PGSql& pgsql
const string vs(write(content(scheme::writeValue(val))));
const char* const params[2] = { c_str(ks), c_str(vs) };
PGresult* const r = PQexecParams(pgsql.conn, c_str(string("insert into ") + pgsql.table + string(" values($1, $2);")), 2, NULL, params, NULL, NULL, 0);
- if (PQresultStatus(r) != PGRES_COMMAND_OK)
- return mkfailure<bool>(string("Couldn't execute insert postgresql SQL statement: ") + pgfailure(r, pgsql.conn));
+ if (PQresultStatus(r) != PGRES_COMMAND_OK) {
+ const string rs = string("Couldn't execute insert postgresql SQL statement: ") + pgfailure(r, pgsql.conn);
+ PQclear(r);
+ return mkfailure<bool>(rs);
+ }
PQclear(r);
debug(true, "pgsql::post::result");
@@ -169,10 +240,13 @@ const failable<bool> put(const value& key, const value& val, const PGSql& pgsql)
const string vs(write(content(scheme::writeValue(val))));
const char* const params[2] = { c_str(ks), c_str(vs) };
PGresult* const r = PQexecParams(pgsql.conn, c_str(string("update ") + pgsql.table + string(" set ") + pgsql.vname + string(" = $2 where ") + pgsql.kname + string(" = $1;")), 2, NULL, params, NULL, NULL, 0);
- if (PQresultStatus(r) != PGRES_COMMAND_OK)
- return mkfailure<bool>(string("Couldn't execute update postgresql SQL statement: ") + pgfailure(r, pgsql.conn));
- const string t = PQcmdTuples(r);
- if (t != "0") {
+ if (PQresultStatus(r) != PGRES_COMMAND_OK) {
+ const string rs = string("Couldn't execute update postgresql SQL statement: ") + pgfailure(r, pgsql.conn);
+ PQclear(r);
+ return mkfailure<bool>(rs);
+ }
+ const char* const t = PQcmdTuples(r);
+ if (t != NULL && strcmp(t, "0")) {
PQclear(r);
debug(true, "pgsql::put::result");
return true;
@@ -180,8 +254,11 @@ const failable<bool> put(const value& key, const value& val, const PGSql& pgsql)
PQclear(r);
PGresult* const pr = PQexecParams(pgsql.conn, c_str(string("insert into ") + pgsql.table + string(" values($1, $2);")), 2, NULL, params, NULL, NULL, 0);
- if (PQresultStatus(pr) != PGRES_COMMAND_OK)
- return mkfailure<bool>(string("Couldn't execute insert postgresql SQL statement: ") + pgfailure(pr, pgsql.conn));
+ if (PQresultStatus(pr) != PGRES_COMMAND_OK) {
+ const string rs = string("Couldn't execute insert postgresql SQL statement: ") + pgfailure(pr, pgsql.conn);
+ PQclear(pr);
+ return mkfailure<bool>(rs);
+ }
PQclear(pr);
debug(true, "pgsql::put::result");
@@ -189,6 +266,57 @@ const failable<bool> put(const value& key, const value& val, const PGSql& pgsql)
}
/**
+ * Patch an item in the database. If the item doesn't exist it is added.
+ */
+const failable<bool> patch(const value& key, const value& val, const PGSql& pgsql) {
+ debug(key, "pgsql::patch::key");
+ debug(val, "pgsql::patch::value");
+ debug(pgsql.conninfo, "pgsql::patch::conninfo");
+ debug(pgsql.table, "pgsql::patch::table");
+ setup(pgsql);
+
+ const string ks(write(content(scheme::writeValue(key))));
+ const string vs(write(content(scheme::writeValue(val))));
+ const char* const params[2] = { c_str(ks), c_str(vs) };
+ PGresult* const r = PQexecParams(pgsql.conn, c_str(string("update ") + pgsql.table + string(" set ") + pgsql.vname + string(" = $2 where ") + pgsql.kname + string(" = $1;")), 2, NULL, params, NULL, NULL, 0);
+ if (PQresultStatus(r) != PGRES_COMMAND_OK) {
+ const string rs = string("Couldn't execute update postgresql SQL statement: ") + pgfailure(r, pgsql.conn);
+ const char* const st = PQresultErrorField(r, PG_DIAG_SQLSTATE);
+ if (st != NULL && !strncmp(st, "40", 2)) {
+
+ // Report a transaction serialization conflict
+ PQclear(r);
+ return mkfailure<bool>(rs, 409);
+ }
+ PQclear(r);
+ return mkfailure<bool>(rs);
+ }
+ const char* const t = PQcmdTuples(r);
+ if (t != NULL && strcmp(t, "0")) {
+ PQclear(r);
+ debug(true, "pgsql::patch::result");
+ return true;
+ }
+ PQclear(r);
+
+ PGresult* const pr = PQexecParams(pgsql.conn, c_str(string("insert into ") + pgsql.table + string(" values($1, $2);")), 2, NULL, params, NULL, NULL, 0);
+ if (PQresultStatus(pr) != PGRES_COMMAND_OK) {
+ const string rs = string("Couldn't execute insert postgresql SQL statement: ") + pgfailure(pr, pgsql.conn);
+ const char* const st = PQresultErrorField(pr, PG_DIAG_SQLSTATE);
+ if (st != NULL && !strncmp(st, "40", 2)) {
+ PQclear(pr);
+ return mkfailure<bool>(rs, 40);
+ }
+ PQclear(pr);
+ return mkfailure<bool>(rs);
+ }
+ PQclear(pr);
+
+ debug(true, "pgsql::patch::result");
+ return true;
+}
+
+/**
* Convert a key to an item id.
*/
const list<value> keyid(const list<value>& key) {
@@ -200,14 +328,14 @@ const list<value> keyid(const list<value>& key) {
}
/**
- * Convert a key to an param name / value assoc.
+ * Convert a key to a (param name, value) assoc.
*/
-const list<list<value> > keyparams(const list<value>& key) {
+const list<value> keyparams(const list<value>& key) {
if (isNil(key))
return nilListValue;
if (!isList(car(key)))
return keyparams(cdr(key));
- return cons<list<value> >((list<value>)car(key), keyparams(cdr(key)));
+ return cons<value>(car(key), keyparams(cdr(key)));
}
/**
@@ -216,9 +344,8 @@ const list<list<value> > keyparams(const list<value>& key) {
const list<value> getitems(PGresult* const r, const int i, const int n) {
if (i == n)
return nilListValue;
- const value key(content(scheme::readValue(string(PQgetvalue(r, i, 0)))));
const value val(content(scheme::readValue(string(PQgetvalue(r, i, 1)))));
- return cons<value>(mklist<value>(key, val), getitems(r, i + 1, n));
+ return cons<value>(val, getitems(r, i + 1, n));
}
/**
@@ -250,12 +377,13 @@ const failable<value> get(const value& key, const PGSql& pgsql) {
// Get item and id and get parameters from the key
const bool lk = isList(key);
- const list<list<value> > kparams = lk? keyparams(key) : list<list<value> >();
+ const list<value> kparams = lk? keyparams(key) : nilListValue;
const list<value> regex = assoc<value>("regex", kparams);
const list<value> like = assoc<value>("like", kparams);
const list<value> textsearch = assoc<value>("textsearch", kparams);
const list<value> limit = assoc<value>("limit", kparams);
const list<value> offset = assoc<value>("offset", kparams);
+ const list<value> rank = assoc<value>("rank", kparams);
const list<value> id = lk? keyid(key) : nilListValue;
const list<value> atable = assoc<value>("table", kparams);
const string table = isNil(atable)? pgsql.table : (string)cadr(atable);
@@ -265,14 +393,20 @@ const failable<value> get(const value& key, const PGSql& pgsql) {
const string vname = isNil(avname)? pgsql.vname : (string)cadr(avname);
// Build the SQL query
- const char* sqlparams[5];
+ const char* sqlparams[6];
int p = 0;
int w = 0;
ostringstream sqlos;
- sqlos << "select data.*";
+ sqlos << "select data." << kname << ", data." << vname;
if (!isNil(textsearch)) {
- // Text search, setup result ranking
- sqlos << ", ts_rank_cd(to_tsvector(data." << vname << "), tsquery, 32) as rank";
+ // Text search, setup text result ranking
+ sqlos << ", ts_rank_cd(to_tsvector(data." << vname << "), tsquery, 32) as tsrank";
+ }
+ if (!isNil(rank)) {
+ // Ranking, setup rank expression
+ const string rs = (string)cadr(rank);
+ sqlparams[p++] = c_str(rs);
+ sqlos << ", $" << p << " as rank";
}
sqlos << " from " << table << " data";
if (!isNil(textsearch)) {
@@ -305,9 +439,13 @@ const failable<value> get(const value& key, const PGSql& pgsql) {
if (!isNil(textsearch)) {
// Text search, apply the query
sqlos << (w == 0? " where" : " and");
- sqlos << " tsquery @@ to_tsvector(data." << vname << ") order by rank desc";
+ sqlos << " tsquery @@ to_tsvector(data." << vname << ")";
w++;
}
+ if (!isNil(textsearch) || !isNil(rank)) {
+ // Result ordering
+ sqlos << " order by" << (isNil(rank)? "" : " rank desc") << ((isNil(rank) || isNil(textsearch))? "" : ",") << (isNil(textsearch)? "" : " tsrank desc");
+ }
if (!isNil(offset)) {
// Result pagination offset
sqlos << " offset " << atoi(c_str((string)cadr(offset)));
@@ -320,8 +458,11 @@ const failable<value> get(const value& key, const PGSql& pgsql) {
const string sqls = str(sqlos);
debug(sqls, "pgsql::get::sqls");
PGresult* r = PQexecParams(pgsql.conn, c_str(sqls), p, NULL, sqlparams, NULL, NULL, 0);
- if (PQresultStatus(r) != PGRES_TUPLES_OK)
- return mkfailure<value>(string("Couldn't execute select postgresql SQL statement: ") + pgfailure(r, pgsql.conn));
+ if (PQresultStatus(r) != PGRES_TUPLES_OK) {
+ const string rs = string("Couldn't execute select postgresql SQL statement: ") + pgfailure(r, pgsql.conn);
+ PQclear(r);
+ return mkfailure<value>(rs);
+ }
const int n = PQntuples(r);
if (n < 1) {
PQclear(r);
@@ -330,7 +471,7 @@ const failable<value> get(const value& key, const PGSql& pgsql) {
return mkfailure<value>(str(os), 404, false);
}
- // Return a collection of key / item pairs
+ // Return a collection of items
if (l != 1) {
const list<value> lval = getitems(r, 0, n);
PQclear(r);
@@ -357,8 +498,18 @@ const failable<bool> del(const value& key, const PGSql& pgsql) {
const string ks(write(content(scheme::writeValue(key))));
const char* const params[1] = { c_str(ks) };
PGresult* const r = PQexecParams(pgsql.conn, c_str(string("delete from ") + pgsql.table + string(" where ") + pgsql.kname + string(" = $1;")), 1, NULL, params, NULL, NULL, 0);
- if (PQresultStatus(r) != PGRES_COMMAND_OK)
- return mkfailure<bool>(string("Couldn't execute delete postgresql SQL statement: ") + pgfailure(r, pgsql.conn));
+ if (PQresultStatus(r) != PGRES_COMMAND_OK) {
+ const string rs = string("Couldn't execute delete postgresql SQL statement: ") + pgfailure(r, pgsql.conn);
+ PQclear(r);
+ return mkfailure<bool>(rs);
+ }
+ const char* const t = PQcmdTuples(r);
+ if (t != NULL && !strcmp(t, "0")) {
+ PQclear(r);
+ ostringstream os;
+ os << "Couldn't delete postgresql entry: " << key;
+ return mkfailure<bool>(str(os), 404, false);
+ }
PQclear(r);
debug(true, "pgsql::delete::result");
diff --git a/sca-cpp/trunk/components/sqldb/sqldb.cpp b/sca-cpp/trunk/components/sqldb/sqldb.cpp
index 1288dd553b..75be2c0624 100644
--- a/sca-cpp/trunk/components/sqldb/sqldb.cpp
+++ b/sca-cpp/trunk/components/sqldb/sqldb.cpp
@@ -64,6 +64,65 @@ const failable<value> put(const list<value>& params, const pgsql::PGSql& pg) {
}
/**
+ * Patch an item in the database.
+ */
+const failable<value> patch(const list<value>& params, const pgsql::PGSql& pg) {
+ // Read patch
+ value p = assoc<value>("patch", assoc<value>("content", car<value>(cadr(params))));
+ if (isNil(p))
+ return mkfailure<value>("Couldn't read patch script");
+ const string script = cadr<value>(p);
+ debug(script, "pgsql::patch::script");
+
+ const lambda<const failable<value>(const value&, const pgsql::PGSql&, const string&, const int)> tryPatch = [&tryPatch](const value& key, const pgsql::PGSql& pg, const string& script, const int count) -> const failable<value> {
+
+ // Begin database transaction
+ const failable<bool> brc = pgsql::begin(pg);
+ if (!hasContent(brc))
+ return mkfailure<value>(brc);
+
+ // Get existing value from database
+ const failable<value> ival = pgsql::get(key, pg);
+ if (!hasContent(ival) && rcode(ival) != 404) {
+ pgsql::rollback(pg);
+ return mkfailure<value>(ival);
+ }
+
+ // Apply patch
+ istringstream is(script);
+ scheme::Env env = scheme::setupEnvironment();
+ const value pval = scheme::evalScript(cons<value>("patch", scheme::quotedParameters(mklist<value>(key, hasContent(ival)? content(ival) : (value)list<value>()))), is, env);
+ if (isNil(pval)) {
+ ostringstream os;
+ os << "Couldn't patch postgresql entry: " << key;
+ return mkfailure<value>(str(os), 404, false);
+ }
+
+ // Push patched value to database
+ const failable<bool> val = pgsql::patch(key, pval, pg);
+ if (!hasContent(val)) {
+ pgsql::rollback(pg);
+
+ // Retry on a transaction serialization error
+ if (rcode(val) == 409 && count > 0)
+ return tryPatch(key, pg, script, count - 1);
+ return mkfailure<value>(val);
+ }
+
+ // Commit database transaction
+ const failable<bool> crc = pgsql::commit(pg);
+ if (!hasContent(crc))
+ return mkfailure<value>(crc);
+
+ return value(content(val));
+ };
+
+ // Try patching the entry and automatically retry a few times on transaction
+ // serialization errors
+ return tryPatch(car(params), pg, script, 5);
+}
+
+/**
* Delete an item from the database.
*/
const failable<value> del(const list<value>& params, const pgsql::PGSql& pg) {
@@ -98,6 +157,8 @@ const failable<value> start(const list<value>& params) {
return post(cdr(params), *pg);
if (func == "put")
return put(cdr(params), *pg);
+ if (func == "patch")
+ return patch(cdr(params), *pg);
if (func == "delete")
return del(cdr(params), *pg);
return mkfailure<value>();